diff options
Diffstat (limited to 'arch/arc/kernel')
30 files changed, 7570 insertions, 0 deletions
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile new file mode 100644 index 00000000000..c242ef07ba7 --- /dev/null +++ b/arch/arc/kernel/Makefile @@ -0,0 +1,33 @@ +# +# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 as +# published by the Free Software Foundation. + +# Pass UTS_MACHINE for user_regset definition +CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"' + +obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o entry.o process.o +obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o clk.o +obj-y += devtree.o + +obj-$(CONFIG_MODULES) += arcksyms.o module.o +obj-$(CONFIG_SMP) += smp.o +obj-$(CONFIG_ARC_DW2_UNWIND) += unwind.o +obj-$(CONFIG_KPROBES) += kprobes.o +obj-$(CONFIG_ARC_MISALIGN_ACCESS) += unaligned.o +obj-$(CONFIG_KGDB) += kgdb.o +obj-$(CONFIG_ARC_METAWARE_HLINK) += arc_hostlink.o + +obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o +CFLAGS_fpu.o += -mdpfp + +ifdef CONFIG_ARC_DW2_UNWIND +CFLAGS_ctx_sw.o += -fno-omit-frame-pointer +obj-y += ctx_sw.o +else +obj-y += ctx_sw_asm.o +endif + +extra-y := vmlinux.lds head.o diff --git a/arch/arc/kernel/arc_hostlink.c b/arch/arc/kernel/arc_hostlink.c new file mode 100644 index 00000000000..47b2a17cc52 --- /dev/null +++ b/arch/arc/kernel/arc_hostlink.c @@ -0,0 +1,58 @@ +/* + * arc_hostlink.c: Pseudo-driver for Metaware provided "hostlink" facility + * + * Allows Linux userland access to host in absence of any peripherals. + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/fs.h> /* file_operations */ +#include <linux/miscdevice.h> +#include <linux/mm.h> /* VM_IO */ +#include <linux/module.h> +#include <linux/uaccess.h> + +static unsigned char __HOSTLINK__[4 * PAGE_SIZE] __aligned(PAGE_SIZE); + +static int arc_hl_mmap(struct file *fp, struct vm_area_struct *vma) +{ + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, + vma->vm_end - vma->vm_start, + vma->vm_page_prot)) { + pr_warn("Hostlink buffer mmap ERROR\n"); + return -EAGAIN; + } + return 0; +} + +static long arc_hl_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + /* we only support, returning the physical addr to mmap in user space */ + put_user((unsigned int)__HOSTLINK__, (int __user *)arg); + return 0; +} + +static const struct file_operations arc_hl_fops = { + .unlocked_ioctl = arc_hl_ioctl, + .mmap = arc_hl_mmap, +}; + +static struct miscdevice arc_hl_dev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "hostlink", + .fops = &arc_hl_fops +}; + +static int __init arc_hl_init(void) +{ + pr_info("ARC Hostlink driver mmap at 0x%p\n", __HOSTLINK__); + return misc_register(&arc_hl_dev); +} +module_init(arc_hl_init); diff --git a/arch/arc/kernel/arcksyms.c b/arch/arc/kernel/arcksyms.c new file mode 100644 index 00000000000..4d9e77724be --- /dev/null +++ b/arch/arc/kernel/arcksyms.c @@ -0,0 +1,56 @@ +/* + * arcksyms.c - Exporting symbols not exportable from their own sources + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/module.h> + +/* libgcc functions, not part of kernel sources */ +extern void __ashldi3(void); +extern void __ashrdi3(void); +extern void __divsi3(void); +extern void __divsf3(void); +extern void __lshrdi3(void); +extern void __modsi3(void); +extern void __muldi3(void); +extern void __ucmpdi2(void); +extern void __udivsi3(void); +extern void __umodsi3(void); +extern void __cmpdi2(void); +extern void __fixunsdfsi(void); +extern void __muldf3(void); +extern void __divdf3(void); +extern void __floatunsidf(void); +extern void __floatunsisf(void); + +EXPORT_SYMBOL(__ashldi3); +EXPORT_SYMBOL(__ashrdi3); +EXPORT_SYMBOL(__divsi3); +EXPORT_SYMBOL(__divsf3); +EXPORT_SYMBOL(__lshrdi3); +EXPORT_SYMBOL(__modsi3); +EXPORT_SYMBOL(__muldi3); +EXPORT_SYMBOL(__ucmpdi2); +EXPORT_SYMBOL(__udivsi3); +EXPORT_SYMBOL(__umodsi3); +EXPORT_SYMBOL(__cmpdi2); +EXPORT_SYMBOL(__fixunsdfsi); +EXPORT_SYMBOL(__muldf3); +EXPORT_SYMBOL(__divdf3); +EXPORT_SYMBOL(__floatunsidf); +EXPORT_SYMBOL(__floatunsisf); + +/* ARC optimised assembler routines */ +EXPORT_SYMBOL(memset); +EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(memcmp); +EXPORT_SYMBOL(strchr); +EXPORT_SYMBOL(strcpy); +EXPORT_SYMBOL(strcmp); +EXPORT_SYMBOL(strlen); diff --git a/arch/arc/kernel/asm-offsets.c b/arch/arc/kernel/asm-offsets.c new file mode 100644 index 00000000000..0dc148ebce7 --- /dev/null +++ b/arch/arc/kernel/asm-offsets.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/thread_info.h> +#include <linux/kbuild.h> +#include <asm/hardirq.h> +#include <asm/page.h> +#include <asm/ptrace.h> + +int main(void) +{ + DEFINE(TASK_THREAD, offsetof(struct task_struct, thread)); + DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, stack)); + + BLANK(); + + DEFINE(THREAD_KSP, offsetof(struct thread_struct, ksp)); + DEFINE(THREAD_CALLEE_REG, offsetof(struct thread_struct, callee_reg)); +#ifdef CONFIG_ARC_CURR_IN_REG + DEFINE(THREAD_USER_R25, offsetof(struct thread_struct, user_r25)); +#endif + DEFINE(THREAD_FAULT_ADDR, + offsetof(struct thread_struct, fault_address)); + + BLANK(); + + DEFINE(THREAD_INFO_FLAGS, offsetof(struct thread_info, flags)); + DEFINE(THREAD_INFO_PREEMPT_COUNT, + offsetof(struct thread_info, preempt_count)); + + BLANK(); + + DEFINE(TASK_ACT_MM, offsetof(struct task_struct, active_mm)); + DEFINE(TASK_TGID, offsetof(struct task_struct, tgid)); + + DEFINE(MM_CTXT, offsetof(struct mm_struct, context)); + DEFINE(MM_PGD, offsetof(struct mm_struct, pgd)); + + DEFINE(MM_CTXT_ASID, offsetof(mm_context_t, asid)); + + BLANK(); + + DEFINE(PT_status32, offsetof(struct pt_regs, status32)); + DEFINE(PT_orig_r8, offsetof(struct pt_regs, orig_r8_word)); + DEFINE(PT_sp, offsetof(struct pt_regs, sp)); + DEFINE(PT_r0, offsetof(struct pt_regs, r0)); + DEFINE(PT_r1, offsetof(struct pt_regs, r1)); + DEFINE(PT_r2, offsetof(struct pt_regs, r2)); + DEFINE(PT_r3, offsetof(struct pt_regs, r3)); + DEFINE(PT_r4, offsetof(struct pt_regs, r4)); + DEFINE(PT_r5, offsetof(struct pt_regs, r5)); + DEFINE(PT_r6, offsetof(struct pt_regs, r6)); + DEFINE(PT_r7, offsetof(struct pt_regs, r7)); + + return 0; +} diff --git a/arch/arc/kernel/clk.c b/arch/arc/kernel/clk.c new file mode 100644 index 00000000000..66ce0dc917f --- /dev/null +++ b/arch/arc/kernel/clk.c @@ -0,0 +1,21 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <asm/clk.h> + +unsigned long core_freq = 800000000; + +/* + * As of now we default to device-tree provided clock + * In future we can determine this in early boot + */ +int arc_set_core_freq(unsigned long freq) +{ + core_freq = freq; + return 0; +} diff --git a/arch/arc/kernel/ctx_sw.c b/arch/arc/kernel/ctx_sw.c new file mode 100644 index 00000000000..60844dac613 --- /dev/null +++ b/arch/arc/kernel/ctx_sw.c @@ -0,0 +1,109 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Vineetg: Aug 2009 + * -"C" version of lowest level context switch asm macro called by schedular + * gcc doesn't generate the dward CFI info for hand written asm, hence can't + * backtrace out of it (e.g. tasks sleeping in kernel). + * So we cheat a bit by writing almost similar code in inline-asm. + * -This is a hacky way of doing things, but there is no other simple way. + * I don't want/intend to extend unwinding code to understand raw asm + */ + +#include <asm/asm-offsets.h> +#include <linux/sched.h> + +struct task_struct *__sched +__switch_to(struct task_struct *prev_task, struct task_struct *next_task) +{ + unsigned int tmp; + unsigned int prev = (unsigned int)prev_task; + unsigned int next = (unsigned int)next_task; + int num_words_to_skip = 1; +#ifdef CONFIG_ARC_CURR_IN_REG + num_words_to_skip++; +#endif + + __asm__ __volatile__( + /* FP/BLINK save generated by gcc (standard function prologue */ + "st.a r13, [sp, -4] \n\t" + "st.a r14, [sp, -4] \n\t" + "st.a r15, [sp, -4] \n\t" + "st.a r16, [sp, -4] \n\t" + "st.a r17, [sp, -4] \n\t" + "st.a r18, [sp, -4] \n\t" + "st.a r19, [sp, -4] \n\t" + "st.a r20, [sp, -4] \n\t" + "st.a r21, [sp, -4] \n\t" + "st.a r22, [sp, -4] \n\t" + "st.a r23, [sp, -4] \n\t" + "st.a r24, [sp, -4] \n\t" +#ifndef CONFIG_ARC_CURR_IN_REG + "st.a r25, [sp, -4] \n\t" +#endif + "sub sp, sp, %4 \n\t" /* create gutter at top */ + + /* set ksp of outgoing task in tsk->thread.ksp */ + "st.as sp, [%3, %1] \n\t" + + "sync \n\t" + + /* + * setup _current_task with incoming tsk. + * optionally, set r25 to that as well + * For SMP extra work to get to &_current_task[cpu] + * (open coded SET_CURR_TASK_ON_CPU) + */ +#ifndef CONFIG_SMP + "st %2, [@_current_task] \n\t" +#else + "lr r24, [identity] \n\t" + "lsr r24, r24, 8 \n\t" + "bmsk r24, r24, 7 \n\t" + "add2 r24, @_current_task, r24 \n\t" + "st %2, [r24] \n\t" +#endif +#ifdef CONFIG_ARC_CURR_IN_REG + "mov r25, %2 \n\t" +#endif + + /* get ksp of incoming task from tsk->thread.ksp */ + "ld.as sp, [%2, %1] \n\t" + + /* start loading it's CALLEE reg file */ + + "add sp, sp, %4 \n\t" /* skip gutter at top */ + +#ifndef CONFIG_ARC_CURR_IN_REG + "ld.ab r25, [sp, 4] \n\t" +#endif + "ld.ab r24, [sp, 4] \n\t" + "ld.ab r23, [sp, 4] \n\t" + "ld.ab r22, [sp, 4] \n\t" + "ld.ab r21, [sp, 4] \n\t" + "ld.ab r20, [sp, 4] \n\t" + "ld.ab r19, [sp, 4] \n\t" + "ld.ab r18, [sp, 4] \n\t" + "ld.ab r17, [sp, 4] \n\t" + "ld.ab r16, [sp, 4] \n\t" + "ld.ab r15, [sp, 4] \n\t" + "ld.ab r14, [sp, 4] \n\t" + "ld.ab r13, [sp, 4] \n\t" + + /* last (ret value) = prev : although for ARC it mov r0, r0 */ + "mov %0, %3 \n\t" + + /* FP/BLINK restore generated by gcc (standard func epilogue */ + + : "=r"(tmp) + : "n"((TASK_THREAD + THREAD_KSP) / 4), "r"(next), "r"(prev), + "n"(num_words_to_skip * 4) + : "blink" + ); + + return (struct task_struct *)tmp; +} diff --git a/arch/arc/kernel/ctx_sw_asm.S b/arch/arc/kernel/ctx_sw_asm.S new file mode 100644 index 00000000000..d8972345e4c --- /dev/null +++ b/arch/arc/kernel/ctx_sw_asm.S @@ -0,0 +1,58 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Vineetg: Aug 2009 + * -Moved core context switch macro out of entry.S into this file. + * -This is the more "natural" hand written assembler + */ + +#include <asm/entry.h> /* For the SAVE_* macros */ +#include <asm/asm-offsets.h> +#include <asm/linkage.h> + +;################### Low Level Context Switch ########################## + + .section .sched.text,"ax",@progbits + .align 4 + .global __switch_to + .type __switch_to, @function +__switch_to: + + /* Save regs on kernel mode stack of task */ + st.a blink, [sp, -4] + st.a fp, [sp, -4] + SAVE_CALLEE_SAVED_KERNEL + + /* Save the now KSP in task->thread.ksp */ + st.as sp, [r0, (TASK_THREAD + THREAD_KSP)/4] + + /* + * Return last task in r0 (return reg) + * On ARC, Return reg = First Arg reg = r0. + * Since we already have last task in r0, + * don't need to do anything special to return it + */ + + /* hardware memory barrier */ + sync + + /* + * switch to new task, contained in r1 + * Temp reg r3 is required to get the ptr to store val + */ + SET_CURR_TASK_ON_CPU r1, r3 + + /* reload SP with kernel mode stack pointer in task->thread.ksp */ + ld.as sp, [r1, (TASK_THREAD + THREAD_KSP)/4] + + /* restore the registers */ + RESTORE_CALLEE_SAVED_KERNEL + ld.ab fp, [sp, 4] + ld.ab blink, [sp, 4] + j [blink] + +ARC_EXIT __switch_to diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c new file mode 100644 index 00000000000..bdee3a81205 --- /dev/null +++ b/arch/arc/kernel/devtree.c @@ -0,0 +1,123 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * Based on reduced version of METAG + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + + +#include <linux/init.h> +#include <linux/reboot.h> +#include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <asm/prom.h> +#include <asm/clk.h> +#include <asm/mach_desc.h> + +/* called from unflatten_device_tree() to bootstrap devicetree itself */ +void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) +{ + return __va(memblock_alloc(size, align)); +} + +/** + * setup_machine_fdt - Machine setup when an dtb was passed to the kernel + * @dt: virtual address pointer to dt blob + * + * If a dtb was passed to the kernel, then use it to choose the correct + * machine_desc and to setup the system. + */ +struct machine_desc * __init setup_machine_fdt(void *dt) +{ + struct boot_param_header *devtree = dt; + struct machine_desc *mdesc = NULL, *mdesc_best = NULL; + unsigned int score, mdesc_score = ~1; + unsigned long dt_root; + const char *model, *compat; + void *clk; + char manufacturer[16]; + unsigned long len; + + /* check device tree validity */ + if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) + return NULL; + + initial_boot_params = devtree; + dt_root = of_get_flat_dt_root(); + + /* + * The kernel could be multi-platform enabled, thus could have many + * "baked-in" machine descriptors. Search thru all for the best + * "compatible" string match. + */ + for_each_machine_desc(mdesc) { + score = of_flat_dt_match(dt_root, mdesc->dt_compat); + if (score > 0 && score < mdesc_score) { + mdesc_best = mdesc; + mdesc_score = score; + } + } + if (!mdesc_best) { + const char *prop; + long size; + + pr_err("\n unrecognized device tree list:\n[ "); + + prop = of_get_flat_dt_prop(dt_root, "compatible", &size); + if (prop) { + while (size > 0) { + printk("'%s' ", prop); + size -= strlen(prop) + 1; + prop += strlen(prop) + 1; + } + } + printk("]\n\n"); + + machine_halt(); + } + + /* compat = "<manufacturer>,<model>" */ + compat = mdesc_best->dt_compat[0]; + + model = strchr(compat, ','); + if (model) + model++; + + strlcpy(manufacturer, compat, model ? model - compat : strlen(compat)); + + pr_info("Board \"%s\" from %s (Manufacturer)\n", model, manufacturer); + + /* Retrieve various information from the /chosen node */ + of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); + + /* Initialize {size,address}-cells info */ + of_scan_flat_dt(early_init_dt_scan_root, NULL); + + /* Setup memory, calling early_init_dt_add_memory_arch */ + of_scan_flat_dt(early_init_dt_scan_memory, NULL); + + clk = of_get_flat_dt_prop(dt_root, "clock-frequency", &len); + if (clk) + arc_set_core_freq(of_read_ulong(clk, len/4)); + + return mdesc_best; +} + +/* + * Copy the flattened DT out of .init since unflattening doesn't copy strings + * and the normal DT APIs refs them from orig flat DT + */ +void __init copy_devtree(void) +{ + void *alloc = early_init_dt_alloc_memory_arch( + be32_to_cpu(initial_boot_params->totalsize), 64); + if (alloc) { + memcpy(alloc, initial_boot_params, + be32_to_cpu(initial_boot_params->totalsize)); + initial_boot_params = alloc; + } +} diff --git a/arch/arc/kernel/disasm.c b/arch/arc/kernel/disasm.c new file mode 100644 index 00000000000..2f390289a79 --- /dev/null +++ b/arch/arc/kernel/disasm.c @@ -0,0 +1,538 @@ +/* + * several functions that help interpret ARC instructions + * used for unaligned accesses, kprobes and kgdb + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/types.h> +#include <linux/kprobes.h> +#include <linux/slab.h> +#include <asm/disasm.h> +#include <asm/uaccess.h> + +#if defined(CONFIG_KGDB) || defined(CONFIG_ARC_MISALIGN_ACCESS) || \ + defined(CONFIG_KPROBES) + +/* disasm_instr: Analyses instruction at addr, stores + * findings in *state + */ +void __kprobes disasm_instr(unsigned long addr, struct disasm_state *state, + int userspace, struct pt_regs *regs, struct callee_regs *cregs) +{ + int fieldA = 0; + int fieldC = 0, fieldCisReg = 0; + uint16_t word1 = 0, word0 = 0; + int subopcode, is_linked, op_format; + uint16_t *ins_ptr; + uint16_t ins_buf[4]; + int bytes_not_copied = 0; + + memset(state, 0, sizeof(struct disasm_state)); + + /* This fetches the upper part of the 32 bit instruction + * in both the cases of Little Endian or Big Endian configurations. */ + if (userspace) { + bytes_not_copied = copy_from_user(ins_buf, + (const void __user *) addr, 8); + if (bytes_not_copied > 6) + goto fault; + ins_ptr = ins_buf; + } else { + ins_ptr = (uint16_t *) addr; + } + + word1 = *((uint16_t *)addr); + + state->major_opcode = (word1 >> 11) & 0x1F; + + /* Check if the instruction is 32 bit or 16 bit instruction */ + if (state->major_opcode < 0x0B) { + if (bytes_not_copied > 4) + goto fault; + state->instr_len = 4; + word0 = *((uint16_t *)(addr+2)); + state->words[0] = (word1 << 16) | word0; + } else { + state->instr_len = 2; + state->words[0] = word1; + } + + /* Read the second word in case of limm */ + word1 = *((uint16_t *)(addr + state->instr_len)); + word0 = *((uint16_t *)(addr + state->instr_len + 2)); + state->words[1] = (word1 << 16) | word0; + + switch (state->major_opcode) { + case op_Bcc: + state->is_branch = 1; + + /* unconditional branch s25, conditional branch s21 */ + fieldA = (IS_BIT(state->words[0], 16)) ? + FIELD_s25(state->words[0]) : + FIELD_s21(state->words[0]); + + state->delay_slot = IS_BIT(state->words[0], 5); + state->target = fieldA + (addr & ~0x3); + state->flow = direct_jump; + break; + + case op_BLcc: + if (IS_BIT(state->words[0], 16)) { + /* Branch and Link*/ + /* unconditional branch s25, conditional branch s21 */ + fieldA = (IS_BIT(state->words[0], 17)) ? + (FIELD_s25(state->words[0]) & ~0x3) : + FIELD_s21(state->words[0]); + + state->flow = direct_call; + } else { + /*Branch On Compare */ + fieldA = FIELD_s9(state->words[0]) & ~0x3; + state->flow = direct_jump; + } + + state->delay_slot = IS_BIT(state->words[0], 5); + state->target = fieldA + (addr & ~0x3); + state->is_branch = 1; + break; + + case op_LD: /* LD<zz> a,[b,s9] */ + state->write = 0; + state->di = BITS(state->words[0], 11, 11); + if (state->di) + break; + state->x = BITS(state->words[0], 6, 6); + state->zz = BITS(state->words[0], 7, 8); + state->aa = BITS(state->words[0], 9, 10); + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->instr_len += 4; + state->aa = 0; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->wb_reg, regs, cregs); + } + state->src2 = FIELD_s9(state->words[0]); + state->dest = FIELD_A(state->words[0]); + state->pref = (state->dest == REG_LIMM); + break; + + case op_ST: + state->write = 1; + state->di = BITS(state->words[0], 5, 5); + if (state->di) + break; + state->aa = BITS(state->words[0], 3, 4); + state->zz = BITS(state->words[0], 1, 2); + state->src1 = FIELD_C(state->words[0]); + if (state->src1 == REG_LIMM) { + state->instr_len += 4; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->src1, regs, cregs); + } + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->aa = 0; + state->instr_len += 4; + state->src2 = state->words[1]; + } else { + state->src2 = get_reg(state->wb_reg, regs, cregs); + } + state->src3 = FIELD_s9(state->words[0]); + break; + + case op_MAJOR_4: + subopcode = MINOR_OPCODE(state->words[0]); + switch (subopcode) { + case 32: /* Jcc */ + case 33: /* Jcc.D */ + case 34: /* JLcc */ + case 35: /* JLcc.D */ + is_linked = 0; + + if (subopcode == 33 || subopcode == 35) + state->delay_slot = 1; + + if (subopcode == 34 || subopcode == 35) + is_linked = 1; + + fieldCisReg = 0; + op_format = BITS(state->words[0], 22, 23); + if (op_format == 0 || ((op_format == 3) && + (!IS_BIT(state->words[0], 5)))) { + fieldC = FIELD_C(state->words[0]); + + if (fieldC == REG_LIMM) { + fieldC = state->words[1]; + state->instr_len += 4; + } else { + fieldCisReg = 1; + } + } else if (op_format == 1 || ((op_format == 3) + && (IS_BIT(state->words[0], 5)))) { + fieldC = FIELD_C(state->words[0]); + } else { + /* op_format == 2 */ + fieldC = FIELD_s12(state->words[0]); + } + + if (!fieldCisReg) { + state->target = fieldC; + state->flow = is_linked ? + direct_call : direct_jump; + } else { + state->target = get_reg(fieldC, regs, cregs); + state->flow = is_linked ? + indirect_call : indirect_jump; + } + state->is_branch = 1; + break; + + case 40: /* LPcc */ + if (BITS(state->words[0], 22, 23) == 3) { + /* Conditional LPcc u7 */ + fieldC = FIELD_C(state->words[0]); + + fieldC = fieldC << 1; + fieldC += (addr & ~0x03); + state->is_branch = 1; + state->flow = direct_jump; + state->target = fieldC; + } + /* For Unconditional lp, next pc is the fall through + * which is updated */ + break; + + case 48 ... 55: /* LD a,[b,c] */ + state->di = BITS(state->words[0], 15, 15); + if (state->di) + break; + state->x = BITS(state->words[0], 16, 16); + state->zz = BITS(state->words[0], 17, 18); + state->aa = BITS(state->words[0], 22, 23); + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->instr_len += 4; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->wb_reg, regs, + cregs); + } + state->src2 = FIELD_C(state->words[0]); + if (state->src2 == REG_LIMM) { + state->instr_len += 4; + state->src2 = state->words[1]; + } else { + state->src2 = get_reg(state->src2, regs, + cregs); + } + state->dest = FIELD_A(state->words[0]); + if (state->dest == REG_LIMM) + state->pref = 1; + break; + + case 10: /* MOV */ + /* still need to check for limm to extract instr len */ + /* MOV is special case because it only takes 2 args */ + switch (BITS(state->words[0], 22, 23)) { + case 0: /* OP a,b,c */ + if (FIELD_C(state->words[0]) == REG_LIMM) + state->instr_len += 4; + break; + case 1: /* OP a,b,u6 */ + break; + case 2: /* OP b,b,s12 */ + break; + case 3: /* OP.cc b,b,c/u6 */ + if ((!IS_BIT(state->words[0], 5)) && + (FIELD_C(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + } + break; + + + default: + /* Not a Load, Jump or Loop instruction */ + /* still need to check for limm to extract instr len */ + switch (BITS(state->words[0], 22, 23)) { + case 0: /* OP a,b,c */ + if ((FIELD_B(state->words[0]) == REG_LIMM) || + (FIELD_C(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + case 1: /* OP a,b,u6 */ + break; + case 2: /* OP b,b,s12 */ + break; + case 3: /* OP.cc b,b,c/u6 */ + if ((!IS_BIT(state->words[0], 5)) && + ((FIELD_B(state->words[0]) == REG_LIMM) || + (FIELD_C(state->words[0]) == REG_LIMM))) + state->instr_len += 4; + break; + } + break; + } + break; + + /* 16 Bit Instructions */ + case op_LD_ADD: /* LD_S|LDB_S|LDW_S a,[b,c] */ + state->zz = BITS(state->words[0], 3, 4); + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->dest = FIELD_S_A(state->words[0]); + break; + + case op_ADD_MOV_CMP: + /* check for limm, ignore mov_s h,b (== mov_s 0,b) */ + if ((BITS(state->words[0], 3, 4) < 3) && + (FIELD_S_H(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + + case op_S: + subopcode = BITS(state->words[0], 5, 7); + switch (subopcode) { + case 0: /* j_s */ + case 1: /* j_s.d */ + case 2: /* jl_s */ + case 3: /* jl_s.d */ + state->target = get_reg(FIELD_S_B(state->words[0]), + regs, cregs); + state->delay_slot = subopcode & 1; + state->flow = (subopcode >= 2) ? + direct_call : indirect_jump; + break; + case 7: + switch (BITS(state->words[0], 8, 10)) { + case 4: /* jeq_s [blink] */ + case 5: /* jne_s [blink] */ + case 6: /* j_s [blink] */ + case 7: /* j_s.d [blink] */ + state->delay_slot = (subopcode == 7); + state->flow = indirect_jump; + state->target = get_reg(31, regs, cregs); + default: + break; + } + default: + break; + } + break; + + case op_LD_S: /* LD_S c, [b, u7] */ + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = FIELD_S_u7(state->words[0]); + state->dest = FIELD_S_C(state->words[0]); + break; + + case op_LDB_S: + case op_STB_S: + /* no further handling required as byte accesses should not + * cause an unaligned access exception */ + state->zz = 1; + break; + + case op_LDWX_S: /* LDWX_S c, [b, u6] */ + state->x = 1; + /* intentional fall-through */ + + case op_LDW_S: /* LDW_S c, [b, u6] */ + state->zz = 2; + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = FIELD_S_u6(state->words[0]); + state->dest = FIELD_S_C(state->words[0]); + break; + + case op_ST_S: /* ST_S c, [b, u7] */ + state->write = 1; + state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src3 = FIELD_S_u7(state->words[0]); + break; + + case op_STW_S: /* STW_S c,[b,u6] */ + state->write = 1; + state->zz = 2; + state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src3 = FIELD_S_u6(state->words[0]); + break; + + case op_SP: /* LD_S|LDB_S b,[sp,u7], ST_S|STB_S b,[sp,u7] */ + /* note: we are ignoring possibility of: + * ADD_S, SUB_S, PUSH_S, POP_S as these should not + * cause unaliged exception anyway */ + state->write = BITS(state->words[0], 6, 6); + state->zz = BITS(state->words[0], 5, 5); + if (state->zz) + break; /* byte accesses should not come here */ + if (!state->write) { + state->src1 = get_reg(28, regs, cregs); + state->src2 = FIELD_S_u7(state->words[0]); + state->dest = FIELD_S_B(state->words[0]); + } else { + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, + cregs); + state->src2 = get_reg(28, regs, cregs); + state->src3 = FIELD_S_u7(state->words[0]); + } + break; + + case op_GP: /* LD_S|LDB_S|LDW_S r0,[gp,s11/s9/s10] */ + /* note: ADD_S r0, gp, s11 is ignored */ + state->zz = BITS(state->words[0], 9, 10); + state->src1 = get_reg(26, regs, cregs); + state->src2 = state->zz ? FIELD_S_s10(state->words[0]) : + FIELD_S_s11(state->words[0]); + state->dest = 0; + break; + + case op_Pcl: /* LD_S b,[pcl,u10] */ + state->src1 = regs->ret & ~3; + state->src2 = FIELD_S_u10(state->words[0]); + state->dest = FIELD_S_B(state->words[0]); + break; + + case op_BR_S: + state->target = FIELD_S_s8(state->words[0]) + (addr & ~0x03); + state->flow = direct_jump; + state->is_branch = 1; + break; + + case op_B_S: + fieldA = (BITS(state->words[0], 9, 10) == 3) ? + FIELD_S_s7(state->words[0]) : + FIELD_S_s10(state->words[0]); + state->target = fieldA + (addr & ~0x03); + state->flow = direct_jump; + state->is_branch = 1; + break; + + case op_BL_S: + state->target = FIELD_S_s13(state->words[0]) + (addr & ~0x03); + state->flow = direct_call; + state->is_branch = 1; + break; + + default: + break; + } + + if (bytes_not_copied <= (8 - state->instr_len)) + return; + +fault: state->fault = 1; +} + +long __kprobes get_reg(int reg, struct pt_regs *regs, + struct callee_regs *cregs) +{ + long *p; + + if (reg <= 12) { + p = ®s->r0; + return p[-reg]; + } + + if (cregs && (reg <= 25)) { + p = &cregs->r13; + return p[13-reg]; + } + + if (reg == 26) + return regs->r26; + if (reg == 27) + return regs->fp; + if (reg == 28) + return regs->sp; + if (reg == 31) + return regs->blink; + + return 0; +} + +void __kprobes set_reg(int reg, long val, struct pt_regs *regs, + struct callee_regs *cregs) +{ + long *p; + + switch (reg) { + case 0 ... 12: + p = ®s->r0; + p[-reg] = val; + break; + case 13 ... 25: + if (cregs) { + p = &cregs->r13; + p[13-reg] = val; + } + break; + case 26: + regs->r26 = val; + break; + case 27: + regs->fp = val; + break; + case 28: + regs->sp = val; + break; + case 31: + regs->blink = val; + break; + default: + break; + } +} + +/* + * Disassembles the insn at @pc and sets @next_pc to next PC (which could be + * @pc +2/4/6 (ARCompact ISA allows free intermixing of 16/32 bit insns). + * + * If @pc is a branch + * -@tgt_if_br is set to branch target. + * -If branch has delay slot, @next_pc updated with actual next PC. + */ +int __kprobes disasm_next_pc(unsigned long pc, struct pt_regs *regs, + struct callee_regs *cregs, + unsigned long *next_pc, unsigned long *tgt_if_br) +{ + struct disasm_state instr; + + memset(&instr, 0, sizeof(struct disasm_state)); + disasm_instr(pc, &instr, 0, regs, cregs); + + *next_pc = pc + instr.instr_len; + + /* Instruction with possible two targets branch, jump and loop */ + if (instr.is_branch) + *tgt_if_br = instr.target; + + /* For the instructions with delay slots, the fall through is the + * instruction following the instruction in delay slot. + */ + if (instr.delay_slot) { + struct disasm_state instr_d; + + disasm_instr(*next_pc, &instr_d, 0, regs, cregs); + + *next_pc += instr_d.instr_len; + } + + /* Zero Overhead Loop - end of the loop */ + if (!(regs->status32 & STATUS32_L) && (*next_pc == regs->lp_end) + && (regs->lp_count > 1)) { + *next_pc = regs->lp_start; + } + + return instr.is_branch; +} + +#endif /* CONFIG_KGDB || CONFIG_MISALIGN_ACCESS || CONFIG_KPROBES */ diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S new file mode 100644 index 00000000000..ef6800ba2f0 --- /dev/null +++ b/arch/arc/kernel/entry.S @@ -0,0 +1,839 @@ +/* + * Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: May 2011 + * -Userspace unaligned access emulation + * + * vineetg: Feb 2011 (ptrace low level code fixes) + * -traced syscall return code (r0) was not saved into pt_regs for restoring + * into user reg-file when traded task rets to user space. + * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs) + * were not invoking post-syscall trace hook (jumping directly into + * ret_from_system_call) + * + * vineetg: Nov 2010: + * -Vector table jumps (@8 bytes) converted into branches (@4 bytes) + * -To maintain the slot size of 8 bytes/vector, added nop, which is + * not executed at runtime. + * + * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) + * -do_signal()invoked upon TIF_RESTORE_SIGMASK as well + * -Wrappers for sys_{,rt_}sigsuspend() nolonger needed as they don't + * need ptregs anymore + * + * Vineetg: Oct 2009 + * -In a rare scenario, Process gets a Priv-V exception and gets scheduled + * out. Since we don't do FAKE RTIE for Priv-V, CPU excpetion state remains + * active (AE bit enabled). This causes a double fault for a subseq valid + * exception. Thus FAKE RTIE needed in low level Priv-Violation handler. + * Instr Error could also cause similar scenario, so same there as well. + * + * Vineetg: March 2009 (Supporting 2 levels of Interrupts) + * + * Vineetg: Aug 28th 2008: Bug #94984 + * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap + * Normally CPU does this automatically, however when doing FAKE rtie, + * we need to explicitly do this. The problem in macros + * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit + * was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit, + * setting it and not clearing it clears ZOL context + * + * Vineetg: May 16th, 2008 + * - r25 now contains the Current Task when in kernel + * + * Vineetg: Dec 22, 2007 + * Minor Surgery of Low Level ISR to make it SMP safe + * - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR + * - _current_task is made an array of NR_CPUS + * - Access of _current_task wrapped inside a macro so that if hardware + * team agrees for a dedicated reg, no other code is touched + * + * Amit Bhor, Rahul Trivedi, Kanika Nema, Sameer Dhavale : Codito Tech 2004 + */ + +/*------------------------------------------------------------------ + * Function ABI + *------------------------------------------------------------------ + * + * Arguments r0 - r7 + * Caller Saved Registers r0 - r12 + * Callee Saved Registers r13- r25 + * Global Pointer (gp) r26 + * Frame Pointer (fp) r27 + * Stack Pointer (sp) r28 + * Interrupt link register (ilink1) r29 + * Interrupt link register (ilink2) r30 + * Branch link register (blink) r31 + *------------------------------------------------------------------ + */ + + .cpu A7 + +;############################ Vector Table ################################# + +.macro VECTOR lbl +#if 1 /* Just in case, build breaks */ + j \lbl +#else + b \lbl + nop +#endif +.endm + + .section .vector, "ax",@progbits + .align 4 + +/* Each entry in the vector table must occupy 2 words. Since it is a jump + * across sections (.vector to .text) we are gauranteed that 'j somewhere' + * will use the 'j limm' form of the intrsuction as long as somewhere is in + * a section other than .vector. + */ + +; ********* Critical System Events ********************** +VECTOR res_service ; 0x0, Restart Vector (0x0) +VECTOR mem_service ; 0x8, Mem exception (0x1) +VECTOR instr_service ; 0x10, Instrn Error (0x2) + +; ******************** Device ISRs ********************** +#ifdef CONFIG_ARC_IRQ3_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +VECTOR handle_interrupt_level1 + +#ifdef CONFIG_ARC_IRQ5_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +#ifdef CONFIG_ARC_IRQ6_LV2 +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +.rept 25 +VECTOR handle_interrupt_level1 ; Other devices +.endr + +/* FOR ARC600: timer = 0x3, uart = 0x8, emac = 0x10 */ + +; ******************** Exceptions ********************** +VECTOR EV_MachineCheck ; 0x100, Fatal Machine check (0x20) +VECTOR EV_TLBMissI ; 0x108, Intruction TLB miss (0x21) +VECTOR EV_TLBMissD ; 0x110, Data TLB miss (0x22) +VECTOR EV_TLBProtV ; 0x118, Protection Violation (0x23) + ; or Misaligned Access +VECTOR EV_PrivilegeV ; 0x120, Privilege Violation (0x24) +VECTOR EV_Trap ; 0x128, Trap exception (0x25) +VECTOR EV_Extension ; 0x130, Extn Intruction Excp (0x26) + +.rept 24 +VECTOR reserved ; Reserved Exceptions +.endr + +#include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */ +#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,TRAP...} */ +#include <asm/errno.h> +#include <asm/arcregs.h> +#include <asm/irqflags.h> + +;##################### Scratch Mem for IRQ stack switching ############# + +ARCFP_DATA int1_saved_reg + .align 32 + .type int1_saved_reg, @object + .size int1_saved_reg, 4 +int1_saved_reg: + .zero 4 + +/* Each Interrupt level needs it's own scratch */ +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + +ARCFP_DATA int2_saved_reg + .type int2_saved_reg, @object + .size int2_saved_reg, 4 +int2_saved_reg: + .zero 4 + +#endif + +; --------------------------------------------- + .section .text, "ax",@progbits + +res_service: ; processor restart + flag 0x1 ; not implemented + nop + nop + +reserved: ; processor restart + rtie ; jump to processor initializations + +;##################### Interrupt Handling ############################## + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS +; --------------------------------------------- +; Level 2 ISR: Can interrupt a Level 1 ISR +; --------------------------------------------- +ARC_ENTRY handle_interrupt_level2 + + ; TODO-vineetg for SMP this wont work + ; free up r9 as scratchpad + st r9, [@int2_saved_reg] + + ;Which mode (user/kernel) was the system in when intr occured + lr r9, [status32_l2] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_INT2 + + ;------------------------------------------------------ + ; if L2 IRQ interrupted a L1 ISR, disable preemption + ;------------------------------------------------------ + + ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) + bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal + + ; A1 is set in status32_l2 + ; bump thread_info->preempt_count (Disable preemption) + GET_CURR_THR_INFO_FROM_SP r10 + ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] + add r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +1: + ;------------------------------------------------------ + ; setup params for Linux common ISR and invoke it + ;------------------------------------------------------ + lr r0, [icause2] + and r0, r0, 0x1f + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x2 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception + +ARC_EXIT handle_interrupt_level2 + +#endif + +; --------------------------------------------- +; Level 1 ISR +; --------------------------------------------- +ARC_ENTRY handle_interrupt_level1 + + /* free up r9 as scratchpad */ +#ifdef CONFIG_SMP + sr r9, [ARC_REG_SCRATCH_DATA0] +#else + st r9, [@int1_saved_reg] +#endif + + ;Which mode (user/kernel) was the system in when intr occured + lr r9, [status32_l1] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_INT1 + + lr r0, [icause1] + and r0, r0, 0x1f + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x1 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception +ARC_EXIT handle_interrupt_level1 + +;################### Non TLB Exception Handling ############################# + +; --------------------------------------------- +; Instruction Error Exception Handler +; --------------------------------------------- + +ARC_ENTRY instr_service + + EXCPN_PROLOG_FREEUP_REG r9 + + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + lr r0, [ecr] + lr r1, [efa] + + mov r2, sp + + FAKE_RET_FROM_EXCPN r9 + + bl do_insterror_or_kprobe + b ret_from_exception +ARC_EXIT instr_service + +; --------------------------------------------- +; Memory Error Exception Handler +; --------------------------------------------- + +ARC_ENTRY mem_service + + EXCPN_PROLOG_FREEUP_REG r9 + + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + lr r0, [ecr] + lr r1, [efa] + mov r2, sp + bl do_memory_error + b ret_from_exception +ARC_EXIT mem_service + +; --------------------------------------------- +; Machine Check Exception Handler +; --------------------------------------------- + +ARC_ENTRY EV_MachineCheck + + EXCPN_PROLOG_FREEUP_REG r9 + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + lr r0, [ecr] + lr r1, [efa] + mov r2, sp + + brne r0, 0x200100, 1f + bl do_tlb_overlap_fault + b ret_from_exception + +1: + ; DEAD END: can't do much, display Regs and HALT + SAVE_CALLEE_SAVED_USER + + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + j do_machine_check_fault + +ARC_EXIT EV_MachineCheck + +; --------------------------------------------- +; Protection Violation Exception Handler +; --------------------------------------------- + +ARC_ENTRY EV_TLBProtV + + EXCPN_PROLOG_FREEUP_REG r9 + + ;Which mode (user/kernel) was the system in when Exception occured + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + ;---------(3) Save some more regs----------------- + ; vineetg: Mar 6th: Random Seg Fault issue #1 + ; ecr and efa were not saved in case an Intr sneaks in + ; after fake rtie + ; + lr r3, [ecr] + lr r4, [efa] + + ; --------(4) Return from CPU Exception Mode --------- + ; Fake a rtie, but rtie to next label + ; That way, subsequently, do_page_fault ( ) executes in pure kernel + ; mode with further Exceptions enabled + + FAKE_RET_FROM_EXCPN r9 + + ;------ (5) Type of Protection Violation? ---------- + ; + ; ProtV Hardware Exception is triggered for Access Faults of 2 types + ; -Access Violaton (WRITE to READ ONLY Page) - for linux COW + ; -Unaligned Access (READ/WRITE on odd boundary) + ; + cmp r3, 0x230400 ; Misaligned data access ? + beq 4f + + ;========= (6a) Access Violation Processing ======== + cmp r3, 0x230100 + mov r1, 0x0 ; if LD exception ? write = 0 + mov.ne r1, 0x1 ; else write = 1 + + mov r2, r4 ; faulting address + mov r0, sp ; pt_regs + bl do_page_fault + b ret_from_exception + + ;========== (6b) Non aligned access ============ +4: + mov r0, r3 ; cause code + mov r1, r4 ; faulting address + mov r2, sp ; pt_regs + +#ifdef CONFIG_ARC_MISALIGN_ACCESS + SAVE_CALLEE_SAVED_USER + mov r3, sp ; callee_regs +#endif + + bl do_misaligned_access + +#ifdef CONFIG_ARC_MISALIGN_ACCESS + DISCARD_CALLEE_SAVED_USER +#endif + + b ret_from_exception + +ARC_EXIT EV_TLBProtV + +; --------------------------------------------- +; Privilege Violation Exception Handler +; --------------------------------------------- +ARC_ENTRY EV_PrivilegeV + + EXCPN_PROLOG_FREEUP_REG r9 + + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + lr r0, [ecr] + lr r1, [efa] + mov r2, sp + + FAKE_RET_FROM_EXCPN r9 + + bl do_privilege_fault + b ret_from_exception +ARC_EXIT EV_PrivilegeV + +; --------------------------------------------- +; Extension Instruction Exception Handler +; --------------------------------------------- +ARC_ENTRY EV_Extension + + EXCPN_PROLOG_FREEUP_REG r9 + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_SYS + + lr r0, [ecr] + lr r1, [efa] + mov r2, sp + bl do_extension_fault + b ret_from_exception +ARC_EXIT EV_Extension + +;######################### System Call Tracing ######################### + +tracesys: + ; save EFA in case tracer wants the PC of traced task + ; using ERET won't work since next-PC has already committed + lr r12, [efa] + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11 + st r12, [r11, THREAD_FAULT_ADDR] + + ; PRE Sys Call Ptrace hook + mov r0, sp ; pt_regs needed + bl @syscall_trace_entry + + ; Tracing code now returns the syscall num (orig or modif) + mov r8, r0 + + ; Do the Sys Call as we normally would. + ; Validate the Sys Call number + cmp r8, NR_syscalls + mov.hi r0, -ENOSYS + bhi tracesys_exit + + ; Restore the sys-call args. Mere invocation of the hook abv could have + ; clobbered them (since they are in scratch regs). The tracer could also + ; have deliberately changed the syscall args: r0-r7 + ld r0, [sp, PT_r0] + ld r1, [sp, PT_r1] + ld r2, [sp, PT_r2] + ld r3, [sp, PT_r3] + ld r4, [sp, PT_r4] + ld r5, [sp, PT_r5] + ld r6, [sp, PT_r6] + ld r7, [sp, PT_r7] + ld.as r9, [sys_call_table, r8] + jl [r9] ; Entry into Sys Call Handler + +tracesys_exit: + st r0, [sp, PT_r0] ; sys call return value in pt_regs + + ;POST Sys Call Ptrace Hook + bl @syscall_trace_exit + b ret_from_exception ; NOT ret_from_system_call at is saves r0 which + ; we'd done before calling post hook above + +;################### Break Point TRAP ########################## + + ; ======= (5b) Trap is due to Break-Point ========= + +trap_with_param: + + ; stop_pc info by gdb needs this info + stw orig_r8_IS_BRKPT, [sp, PT_orig_r8] + + mov r0, r12 + lr r1, [efa] + mov r2, sp + + ; Now that we have read EFA, its safe to do "fake" rtie + ; and get out of CPU exception mode + FAKE_RET_FROM_EXCPN r11 + + ; Save callee regs in case gdb wants to have a look + ; SP will grow up by size of CALLEE Reg-File + ; NOTE: clobbers r12 + SAVE_CALLEE_SAVED_USER + + ; save location of saved Callee Regs @ thread_struct->pc + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + ; Call the trap handler + bl do_non_swi_trap + + ; unwind stack to discard Callee saved Regs + DISCARD_CALLEE_SAVED_USER + + b ret_from_exception + +;##################### Trap Handling ############################## +; +; EV_Trap caused by TRAP_S and TRAP0 instructions. +;------------------------------------------------------------------ +; (1) System Calls +; :parameters in r0-r7. +; :r8 has the system call number +; (2) Break Points +;------------------------------------------------------------------ + +ARC_ENTRY EV_Trap + + ; Need at least 1 reg to code the early exception prolog + EXCPN_PROLOG_FREEUP_REG r9 + + ;Which mode (user/kernel) was the system in when intr occured + lr r9, [erstatus] + + SWITCH_TO_KERNEL_STK + SAVE_ALL_TRAP + + ;------- (4) What caused the Trap -------------- + lr r12, [ecr] + and.f 0, r12, ECR_PARAM_MASK + bnz trap_with_param + + ; ======= (5a) Trap is due to System Call ======== + + ; Before doing anything, return from CPU Exception Mode + FAKE_RET_FROM_EXCPN r11 + + ; If syscall tracing ongoing, invoke pre-pos-hooks + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys ; this never comes back + + ;============ This is normal System Call case ========== + ; Sys-call num shd not exceed the total system calls avail + cmp r8, NR_syscalls + mov.hi r0, -ENOSYS + bhi ret_from_system_call + + ; Offset into the syscall_table and call handler + ld.as r9,[sys_call_table, r8] + jl [r9] ; Entry into Sys Call Handler + + ; fall through to ret_from_system_call +ARC_EXIT EV_Trap + +ARC_ENTRY ret_from_system_call + + st r0, [sp, PT_r0] ; sys call return value in pt_regs + + ; fall through yet again to ret_from_exception + +;############# Return from Intr/Excp/Trap (Linux Specifics) ############## +; +; If ret to user mode do we need to handle signals, schedule() et al. + +ARC_ENTRY ret_from_exception + + ; Pre-{IRQ,Trap,Exception} K/U mode from pt_regs->status32 + ld r8, [sp, PT_status32] ; returning to User/Kernel Mode + +#ifdef CONFIG_PREEMPT + bbit0 r8, STATUS_U_BIT, resume_kernel_mode +#else + bbit0 r8, STATUS_U_BIT, restore_regs +#endif + + ; Before returning to User mode check-for-and-complete any pending work + ; such as rescheduling/signal-delivery etc. +resume_user_mode_begin: + + ; Disable IRQs to ensures that chk for pending work itself is atomic + ; (and we don't end up missing a NEED_RESCHED/SIGPENDING due to an + ; interim IRQ). + IRQ_DISABLE r10 + + ; Fast Path return to user mode if no pending work + GET_CURR_THR_INFO_FLAGS r9 + and.f 0, r9, _TIF_WORK_MASK + bz restore_regs + + ; --- (Slow Path #1) task preemption --- + bbit0 r9, TIF_NEED_RESCHED, .Lchk_pend_signals + mov blink, resume_user_mode_begin ; tail-call to U mode ret chks + b @schedule ; BTST+Bnz causes relo error in link + +.Lchk_pend_signals: + IRQ_ENABLE r10 + + ; --- (Slow Path #2) pending signal --- + mov r0, sp ; pt_regs for arg to do_signal()/do_notify_resume() + + bbit0 r9, TIF_SIGPENDING, .Lchk_notify_resume + + ; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs + ; in pt_reg since the "C" ABI (kernel code) will automatically + ; save/restore callee-saved regs. + ; + ; However, here we need to explicitly save callee regs because + ; (i) If this signal causes coredump - full regfile needed + ; (ii) If signal is SIGTRAP/SIGSTOP, task is being traced thus + ; tracer might call PEEKUSR(CALLEE reg) + ; + ; NOTE: SP will grow up by size of CALLEE Reg-File + SAVE_CALLEE_SAVED_USER ; clobbers r12 + + ; save location of saved Callee Regs @ thread_struct->callee + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + bl @do_signal + + ; Ideally we want to discard the Callee reg above, however if this was + ; a tracing signal, tracer could have done a POKEUSR(CALLEE reg) + RESTORE_CALLEE_SAVED_USER + + b resume_user_mode_begin ; loop back to start of U mode ret + + ; --- (Slow Path #3) notify_resume --- +.Lchk_notify_resume: + btst r9, TIF_NOTIFY_RESUME + blnz @do_notify_resume + b resume_user_mode_begin ; unconditionally back to U mode ret chks + ; for single exit point from this block + +#ifdef CONFIG_PREEMPT + +resume_kernel_mode: + + ; Can't preempt if preemption disabled + GET_CURR_THR_INFO_FROM_SP r10 + ld r8, [r10, THREAD_INFO_PREEMPT_COUNT] + brne r8, 0, restore_regs + + ; check if this task's NEED_RESCHED flag set + ld r9, [r10, THREAD_INFO_FLAGS] + bbit0 r9, TIF_NEED_RESCHED, restore_regs + + IRQ_DISABLE r9 + + ; Invoke PREEMPTION + bl preempt_schedule_irq + + ; preempt_schedule_irq() always returns with IRQ disabled +#endif + + ; fall through + +;############# Return from Intr/Excp/Trap (ARC Specifics) ############## +; +; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) +; IRQ shd definitely not happen between now and rtie + +restore_regs : + + ; Disable Interrupts while restoring reg-file back + ; XXX can this be optimised out + IRQ_DISABLE_SAVE r9, r10 ;@r10 has prisitine (pre-disable) copy + +#ifdef CONFIG_ARC_CURR_IN_REG + ; Restore User R25 + ; Earlier this used to be only for returning to user mode + ; However with 2 levels of IRQ this can also happen even if + ; in kernel mode + ld r9, [sp, PT_sp] + brhs r9, VMALLOC_START, 8f + RESTORE_USER_R25 +8: +#endif + + ; Restore REG File. In case multiple Events outstanding, + ; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None + ; Note that we use realtime STATUS32 (not pt_regs->status32) to + ; decide that. + + ; if Returning from Exception + bbit0 r10, STATUS_AE_BIT, not_exception + RESTORE_ALL_SYS + rtie + + ; Not Exception so maybe Interrupts (Level 1 or 2) + +not_exception: + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + + bbit0 r10, STATUS_A2_BIT, not_level2_interrupt + + ;------------------------------------------------------------------ + ; if L2 IRQ interrupted a L1 ISR, we'd disbaled preemption earlier + ; so that sched doesnt move to new task, causing L1 to be delayed + ; undeterministically. Now that we've achieved that, lets reset + ; things to what they were, before returning from L2 context + ;---------------------------------------------------------------- + + ldw r9, [sp, PT_orig_r8] ; get orig_r8 to make sure it is + brne r9, orig_r8_IS_IRQ2, 149f ; infact a L2 ISR ret path + + ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) + bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal + + ; A1 is set in status32_l2 + ; decrement thread_info->preempt_count (re-enable preemption) + GET_CURR_THR_INFO_FROM_SP r10 + ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] + + ; paranoid check, given A1 was active when A2 happened, preempt count + ; must not be 0 beccause we would have incremented it. + ; If this does happen we simply HALT as it means a BUG !!! + cmp r9, 0 + bnz 2f + flag 1 + +2: + sub r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +149: + ;return from level 2 + RESTORE_ALL_INT2 +debug_marker_l2: + rtie + +not_level2_interrupt: + +#endif + + bbit0 r10, STATUS_A1_BIT, not_level1_interrupt + + ;return from level 1 + + RESTORE_ALL_INT1 +debug_marker_l1: + rtie + +not_level1_interrupt: + + ;this case is for syscalls or Exceptions (with fake rtie) + + RESTORE_ALL_SYS +debug_marker_syscall: + rtie + +ARC_EXIT ret_from_exception + +ARC_ENTRY ret_from_fork + ; when the forked child comes here from the __switch_to function + ; r0 has the last task pointer. + ; put last task in scheduler queue + bl @schedule_tail + + ; If kernel thread, jump to it's entry-point + ld r9, [sp, PT_status32] + brne r9, 0, 1f + + jl.d [r14] + mov r0, r13 ; arg to payload + +1: + ; special case of kernel_thread entry point returning back due to + ; kernel_execve() - pretend return from syscall to ret to userland + b ret_from_exception +ARC_EXIT ret_from_fork + +;################### Special Sys Call Wrappers ########################## + +; TBD: call do_fork directly from here +ARC_ENTRY sys_fork_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_fork + DISCARD_CALLEE_SAVED_USER + + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys_exit + + b ret_from_system_call +ARC_EXIT sys_fork_wrapper + +ARC_ENTRY sys_vfork_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_vfork + DISCARD_CALLEE_SAVED_USER + + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys_exit + + b ret_from_system_call +ARC_EXIT sys_vfork_wrapper + +ARC_ENTRY sys_clone_wrapper + SAVE_CALLEE_SAVED_USER + bl @sys_clone + DISCARD_CALLEE_SAVED_USER + + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys_exit + + b ret_from_system_call +ARC_EXIT sys_clone_wrapper + +#ifdef CONFIG_ARC_DW2_UNWIND +; Workaround for bug 94179 (STAR ): +; Despite -fasynchronous-unwind-tables, linker is not making dwarf2 unwinder +; section (.debug_frame) as loadable. So we force it here. +; This also fixes STAR 9000487933 where the prev-workaround (objcopy --setflag) +; would not work after a clean build due to kernel build system dependencies. +.section .debug_frame, "wa",@progbits +#endif diff --git a/arch/arc/kernel/fpu.c b/arch/arc/kernel/fpu.c new file mode 100644 index 00000000000..f352e512cbd --- /dev/null +++ b/arch/arc/kernel/fpu.c @@ -0,0 +1,55 @@ +/* + * fpu.c - save/restore of Floating Point Unit Registers on task switch + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/sched.h> +#include <asm/switch_to.h> + +/* + * To save/restore FPU regs, simplest scheme would use LR/SR insns. + * However since SR serializes the pipeline, an alternate "hack" can be used + * which uses the FPU Exchange insn (DEXCL) to r/w FPU regs. + * + * Store to 64bit dpfp1 reg from a pair of core regs: + * dexcl1 0, r1, r0 ; where r1:r0 is the 64 bit val + * + * Read from dpfp1 into pair of core regs (w/o clobbering dpfp1) + * mov_s r3, 0 + * daddh11 r1, r3, r3 ; get "hi" into r1 (dpfp1 unchanged) + * dexcl1 r0, r1, r3 ; get "low" into r0 (dpfp1 low clobbered) + * dexcl1 0, r1, r0 ; restore dpfp1 to orig value + * + * However we can tweak the read, so that read-out of outgoing task's FPU regs + * and write of incoming task's regs happen in one shot. So all the work is + * done before context switch + */ + +void fpu_save_restore(struct task_struct *prev, struct task_struct *next) +{ + unsigned int *saveto = &prev->thread.fpu.aux_dpfp[0].l; + unsigned int *readfrom = &next->thread.fpu.aux_dpfp[0].l; + + const unsigned int zero = 0; + + __asm__ __volatile__( + "daddh11 %0, %2, %2\n" + "dexcl1 %1, %3, %4\n" + : "=&r" (*(saveto + 1)), /* early clobber must here */ + "=&r" (*(saveto)) + : "r" (zero), "r" (*(readfrom + 1)), "r" (*(readfrom)) + ); + + __asm__ __volatile__( + "daddh22 %0, %2, %2\n" + "dexcl2 %1, %3, %4\n" + : "=&r"(*(saveto + 3)), /* early clobber must here */ + "=&r"(*(saveto + 2)) + : "r" (zero), "r" (*(readfrom + 3)), "r" (*(readfrom + 2)) + ); +} diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S new file mode 100644 index 00000000000..006dec3fc35 --- /dev/null +++ b/arch/arc/kernel/head.S @@ -0,0 +1,111 @@ +/* + * ARC CPU startup Code + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Vineetg: Dec 2007 + * -Check if we are running on Simulator or on real hardware + * to skip certain things during boot on simulator + */ + +#include <asm/asm-offsets.h> +#include <asm/entry.h> +#include <linux/linkage.h> +#include <asm/arcregs.h> + + .cpu A7 + + .section .init.text, "ax",@progbits + .type stext, @function + .globl stext +stext: + ;------------------------------------------------------------------- + ; Don't clobber r0-r4 yet. It might have bootloader provided info + ;------------------------------------------------------------------- + +#ifdef CONFIG_SMP + ; Only Boot (Master) proceeds. Others wait in platform dependent way + ; IDENTITY Reg [ 3 2 1 0 ] + ; (cpu-id) ^^^ => Zero for UP ARC700 + ; => #Core-ID if SMP (Master 0) + GET_CPU_ID r5 + cmp r5, 0 + jnz arc_platform_smp_wait_to_boot +#endif + ; Clear BSS before updating any globals + ; XXX: use ZOL here + mov r5, __bss_start + mov r6, __bss_stop +1: + st.ab 0, [r5,4] + brlt r5, r6, 1b + +#ifdef CONFIG_CMDLINE_UBOOT + ; support for bootloader provided cmdline + ; If cmdline passed by u-boot, then + ; r0 = 1 (because ATAGS parsing, now retired, used to use 0) + ; r1 = magic number (board identity) + ; r2 = addr of cmdline string (somewhere in memory/flash) + + brne r0, 1, .Lother_bootup_chores ; u-boot didn't pass cmdline + breq r2, 0, .Lother_bootup_chores ; or cmdline is NULL + + mov r5, @command_line +1: + ldb.ab r6, [r2, 1] + breq r6, 0, .Lother_bootup_chores + b.d 1b + stb.ab r6, [r5, 1] +#endif + +.Lother_bootup_chores: + + ; Identify if running on ISS vs Silicon + ; IDENTITY Reg [ 3 2 1 0 ] + ; (chip-id) ^^^^^ ==> 0xffff for ISS + lr r0, [identity] + lsr r3, r0, 16 + cmp r3, 0xffff + mov.z r4, 0 + mov.nz r4, 1 + st r4, [@running_on_hw] + + ; setup "current" tsk and optionally cache it in dedicated r25 + mov r9, @init_task + SET_CURR_TASK_ON_CPU r9, r0 ; r9 = tsk, r0 = scratch + + ; setup stack (fp, sp) + mov fp, 0 + + ; tsk->thread_info is really a PAGE, whose bottom hoists stack + GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output) + + j start_kernel ; "C" entry point + +#ifdef CONFIG_SMP +;---------------------------------------------------------------- +; First lines of code run by secondary before jumping to 'C' +;---------------------------------------------------------------- + .section .init.text, "ax",@progbits + .type first_lines_of_secondary, @function + .globl first_lines_of_secondary + +first_lines_of_secondary: + + ; setup per-cpu idle task as "current" on this CPU + ld r0, [@secondary_idle_tsk] + SET_CURR_TASK_ON_CPU r0, r1 + + ; setup stack (fp, sp) + mov fp, 0 + + ; set it's stack base to tsk->thread_info bottom + GET_TSK_STACK_BASE r0, sp + + j start_kernel_secondary + +#endif diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c new file mode 100644 index 00000000000..551c10dff48 --- /dev/null +++ b/arch/arc/kernel/irq.c @@ -0,0 +1,273 @@ +/* + * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/irqdomain.h> +#include <asm/sections.h> +#include <asm/irq.h> +#include <asm/mach_desc.h> + +/* + * Early Hardware specific Interrupt setup + * -Called very early (start_kernel -> setup_arch -> setup_processor) + * -Platform Independent (must for any ARC700) + * -Needed for each CPU (hence not foldable into init_IRQ) + * + * what it does ? + * -setup Vector Table Base Reg - in case Linux not linked at 0x8000_0000 + * -Disable all IRQs (on CPU side) + * -Optionally, setup the High priority Interrupts as Level 2 IRQs + */ +void __init arc_init_IRQ(void) +{ + int level_mask = 0; + + write_aux_reg(AUX_INTR_VEC_BASE, _int_vec_base_lds); + + /* Disable all IRQs: enable them as devices request */ + write_aux_reg(AUX_IENABLE, 0); + + /* setup any high priority Interrupts (Level2 in ARCompact jargon) */ +#ifdef CONFIG_ARC_IRQ3_LV2 + level_mask |= (1 << 3); +#endif +#ifdef CONFIG_ARC_IRQ5_LV2 + level_mask |= (1 << 5); +#endif +#ifdef CONFIG_ARC_IRQ6_LV2 + level_mask |= (1 << 6); +#endif + + if (level_mask) { + pr_info("Level-2 interrupts bitset %x\n", level_mask); + write_aux_reg(AUX_IRQ_LEV, level_mask); + } +} + +/* + * ARC700 core includes a simple on-chip intc supporting + * -per IRQ enable/disable + * -2 levels of interrupts (high/low) + * -all interrupts being level triggered + * + * To reduce platform code, we assume all IRQs directly hooked-up into intc. + * Platforms with external intc, hence cascaded IRQs, are free to over-ride + * below, per IRQ. + */ + +static void arc_mask_irq(struct irq_data *data) +{ + arch_mask_irq(data->irq); +} + +static void arc_unmask_irq(struct irq_data *data) +{ + arch_unmask_irq(data->irq); +} + +static struct irq_chip onchip_intc = { + .name = "ARC In-core Intc", + .irq_mask = arc_mask_irq, + .irq_unmask = arc_unmask_irq, +}; + +static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + if (irq == TIMER0_IRQ) + irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq); + else + irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq); + + return 0; +} + +static const struct irq_domain_ops arc_intc_domain_ops = { + .xlate = irq_domain_xlate_onecell, + .map = arc_intc_domain_map, +}; + +static struct irq_domain *root_domain; + +void __init init_onchip_IRQ(void) +{ + struct device_node *intc = NULL; + + intc = of_find_compatible_node(NULL, NULL, "snps,arc700-intc"); + if(!intc) + panic("DeviceTree Missing incore intc\n"); + + root_domain = irq_domain_add_legacy(intc, NR_IRQS, 0, 0, + &arc_intc_domain_ops, NULL); + + if (!root_domain) + panic("root irq domain not avail\n"); + + /* with this we don't need to export root_domain */ + irq_set_default_host(root_domain); +} + +/* + * Late Interrupt system init called from start_kernel for Boot CPU only + * + * Since slab must already be initialized, platforms can start doing any + * needed request_irq( )s + */ +void __init init_IRQ(void) +{ + init_onchip_IRQ(); + + /* Any external intc can be setup here */ + if (machine_desc->init_irq) + machine_desc->init_irq(); + +#ifdef CONFIG_SMP + /* Master CPU can initialize it's side of IPI */ + if (machine_desc->init_smp) + machine_desc->init_smp(smp_processor_id()); +#endif +} + +/* + * "C" Entry point for any ARC ISR, called from low level vector handler + * @irq is the vector number read from ICAUSE reg of on-chip intc + */ +void arch_do_IRQ(unsigned int irq, struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + + irq_enter(); + generic_handle_irq(irq); + irq_exit(); + set_irq_regs(old_regs); +} + +int __init get_hw_config_num_irq(void) +{ + uint32_t val = read_aux_reg(ARC_REG_VECBASE_BCR); + + switch (val & 0x03) { + case 0: + return 16; + case 1: + return 32; + case 2: + return 8; + default: + return 0; + } + + return 0; +} + +/* + * arch_local_irq_enable - Enable interrupts. + * + * 1. Explicitly called to re-enable interrupts + * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc + * which maybe in hard ISR itself + * + * Semantics of this function change depending on where it is called from: + * + * -If called from hard-ISR, it must not invert interrupt priorities + * e.g. suppose TIMER is high priority (Level 2) IRQ + * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times. + * Here local_irq_enable( ) shd not re-enable lower priority interrupts + * -If called from soft-ISR, it must re-enable all interrupts + * soft ISR are low prioity jobs which can be very slow, thus all IRQs + * must be enabled while they run. + * Now hardware context wise we may still be in L2 ISR (not done rtie) + * still we must re-enable both L1 and L2 IRQs + * Another twist is prev scenario with flow being + * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR + * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get + * over-written (this is deficiency in ARC700 Interrupt mechanism) + */ + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */ + +void arch_local_irq_enable(void) +{ + + unsigned long flags; + flags = arch_local_save_flags(); + + /* Allow both L1 and L2 at the onset */ + flags |= (STATUS_E1_MASK | STATUS_E2_MASK); + + /* Called from hard ISR (between irq_enter and irq_exit) */ + if (in_irq()) { + + /* If in L2 ISR, don't re-enable any further IRQs as this can + * cause IRQ priorities to get upside down. e.g. it could allow + * L1 be taken while in L2 hard ISR which is wrong not only in + * theory, it can also cause the dreaded L1-L2-L1 scenario + */ + if (flags & STATUS_A2_MASK) + flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK); + + /* Even if in L1 ISR, allowe Higher prio L2 IRQs */ + else if (flags & STATUS_A1_MASK) + flags &= ~(STATUS_E1_MASK); + } + + /* called from soft IRQ, ideally we want to re-enable all levels */ + + else if (in_softirq()) { + + /* However if this is case of L1 interrupted by L2, + * re-enabling both may cause whaco L1-L2-L1 scenario + * because ARC700 allows level 1 to interrupt an active L2 ISR + * Thus we disable both + * However some code, executing in soft ISR wants some IRQs + * to be enabled so we re-enable L2 only + * + * How do we determine L1 intr by L2 + * -A2 is set (means in L2 ISR) + * -E1 is set in this ISR's pt_regs->status32 which is + * saved copy of status32_l2 when l2 ISR happened + */ + struct pt_regs *pt = get_irq_regs(); + if ((flags & STATUS_A2_MASK) && pt && + (pt->status32 & STATUS_A1_MASK)) { + /*flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK); */ + flags &= ~(STATUS_E1_MASK); + } + } + + arch_local_irq_restore(flags); +} + +#else /* ! CONFIG_ARC_COMPACT_IRQ_LEVELS */ + +/* + * Simpler version for only 1 level of interrupt + * Here we only Worry about Level 1 Bits + */ +void arch_local_irq_enable(void) +{ + unsigned long flags; + + /* + * ARC IDE Drivers tries to re-enable interrupts from hard-isr + * context which is simply wrong + */ + if (in_irq()) { + WARN_ONCE(1, "IRQ enabled from hard-isr"); + return; + } + + flags = arch_local_save_flags(); + flags |= (STATUS_E1_MASK | STATUS_E2_MASK); + arch_local_irq_restore(flags); +} +#endif +EXPORT_SYMBOL(arch_local_irq_enable); diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c new file mode 100644 index 00000000000..2888ba5be47 --- /dev/null +++ b/arch/arc/kernel/kgdb.c @@ -0,0 +1,205 @@ +/* + * kgdb support for ARC + * + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kgdb.h> +#include <asm/disasm.h> +#include <asm/cacheflush.h> + +static void to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs, + struct callee_regs *cregs) +{ + int regno; + + for (regno = 0; regno <= 26; regno++) + gdb_regs[_R0 + regno] = get_reg(regno, kernel_regs, cregs); + + for (regno = 27; regno < GDB_MAX_REGS; regno++) + gdb_regs[regno] = 0; + + gdb_regs[_FP] = kernel_regs->fp; + gdb_regs[__SP] = kernel_regs->sp; + gdb_regs[_BLINK] = kernel_regs->blink; + gdb_regs[_RET] = kernel_regs->ret; + gdb_regs[_STATUS32] = kernel_regs->status32; + gdb_regs[_LP_COUNT] = kernel_regs->lp_count; + gdb_regs[_LP_END] = kernel_regs->lp_end; + gdb_regs[_LP_START] = kernel_regs->lp_start; + gdb_regs[_BTA] = kernel_regs->bta; + gdb_regs[_STOP_PC] = kernel_regs->ret; +} + +static void from_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs, + struct callee_regs *cregs) +{ + int regno; + + for (regno = 0; regno <= 26; regno++) + set_reg(regno, gdb_regs[regno + _R0], kernel_regs, cregs); + + kernel_regs->fp = gdb_regs[_FP]; + kernel_regs->sp = gdb_regs[__SP]; + kernel_regs->blink = gdb_regs[_BLINK]; + kernel_regs->ret = gdb_regs[_RET]; + kernel_regs->status32 = gdb_regs[_STATUS32]; + kernel_regs->lp_count = gdb_regs[_LP_COUNT]; + kernel_regs->lp_end = gdb_regs[_LP_END]; + kernel_regs->lp_start = gdb_regs[_LP_START]; + kernel_regs->bta = gdb_regs[_BTA]; +} + + +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs) +{ + to_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *) + current->thread.callee_reg); +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs) +{ + from_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *) + current->thread.callee_reg); +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, + struct task_struct *task) +{ + if (task) + to_gdb_regs(gdb_regs, task_pt_regs(task), + (struct callee_regs *) task->thread.callee_reg); +} + +struct single_step_data_t { + uint16_t opcode[2]; + unsigned long address[2]; + int is_branch; + int armed; +} single_step_data; + +static void undo_single_step(struct pt_regs *regs) +{ + if (single_step_data.armed) { + int i; + + for (i = 0; i < (single_step_data.is_branch ? 2 : 1); i++) { + memcpy((void *) single_step_data.address[i], + &single_step_data.opcode[i], + BREAK_INSTR_SIZE); + + flush_icache_range(single_step_data.address[i], + single_step_data.address[i] + + BREAK_INSTR_SIZE); + } + single_step_data.armed = 0; + } +} + +static void place_trap(unsigned long address, void *save) +{ + memcpy(save, (void *) address, BREAK_INSTR_SIZE); + memcpy((void *) address, &arch_kgdb_ops.gdb_bpt_instr, + BREAK_INSTR_SIZE); + flush_icache_range(address, address + BREAK_INSTR_SIZE); +} + +static void do_single_step(struct pt_regs *regs) +{ + single_step_data.is_branch = disasm_next_pc((unsigned long) + regs->ret, regs, (struct callee_regs *) + current->thread.callee_reg, + &single_step_data.address[0], + &single_step_data.address[1]); + + place_trap(single_step_data.address[0], &single_step_data.opcode[0]); + + if (single_step_data.is_branch) { + place_trap(single_step_data.address[1], + &single_step_data.opcode[1]); + } + + single_step_data.armed++; +} + +int kgdb_arch_handle_exception(int e_vector, int signo, int err_code, + char *remcomInBuffer, char *remcomOutBuffer, + struct pt_regs *regs) +{ + unsigned long addr; + char *ptr; + + undo_single_step(regs); + + switch (remcomInBuffer[0]) { + case 's': + case 'c': + ptr = &remcomInBuffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->ret = addr; + + case 'D': + case 'k': + atomic_set(&kgdb_cpu_doing_single_step, -1); + + if (remcomInBuffer[0] == 's') { + do_single_step(regs); + atomic_set(&kgdb_cpu_doing_single_step, + smp_processor_id()); + } + + return 0; + } + return -1; +} + +unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs) +{ + return instruction_pointer(regs); +} + +int kgdb_arch_init(void) +{ + single_step_data.armed = 0; + return 0; +} + +void kgdb_trap(struct pt_regs *regs, int param) +{ + /* trap_s 3 is used for breakpoints that overwrite existing + * instructions, while trap_s 4 is used for compiled breakpoints. + * + * with trap_s 3 breakpoints the original instruction needs to be + * restored and continuation needs to start at the location of the + * breakpoint. + * + * with trap_s 4 (compiled) breakpoints, continuation needs to + * start after the breakpoint. + */ + if (param == 3) + instruction_pointer(regs) -= BREAK_INSTR_SIZE; + + kgdb_handle_exception(1, SIGTRAP, 0, regs); +} + +void kgdb_arch_exit(void) +{ +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) +{ + instruction_pointer(regs) = ip; +} + +struct kgdb_arch arch_kgdb_ops = { + /* breakpoint instruction: TRAP_S 0x3 */ +#ifdef CONFIG_CPU_BIG_ENDIAN + .gdb_bpt_instr = {0x78, 0x7e}, +#else + .gdb_bpt_instr = {0x7e, 0x78}, +#endif +}; diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c new file mode 100644 index 00000000000..3bfeacb674d --- /dev/null +++ b/arch/arc/kernel/kprobes.c @@ -0,0 +1,525 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/types.h> +#include <linux/kprobes.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/kprobes.h> +#include <linux/kdebug.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <asm/cacheflush.h> +#include <asm/current.h> +#include <asm/disasm.h> + +#define MIN_STACK_SIZE(addr) min((unsigned long)MAX_STACK_SIZE, \ + (unsigned long)current_thread_info() + THREAD_SIZE - (addr)) + +DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL; +DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); + +int __kprobes arch_prepare_kprobe(struct kprobe *p) +{ + /* Attempt to probe at unaligned address */ + if ((unsigned long)p->addr & 0x01) + return -EINVAL; + + /* Address should not be in exception handling code */ + + p->ainsn.is_short = is_short_instr((unsigned long)p->addr); + p->opcode = *p->addr; + + return 0; +} + +void __kprobes arch_arm_kprobe(struct kprobe *p) +{ + *p->addr = UNIMP_S_INSTRUCTION; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); +} + +void __kprobes arch_disarm_kprobe(struct kprobe *p) +{ + *p->addr = p->opcode; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); +} + +void __kprobes arch_remove_kprobe(struct kprobe *p) +{ + arch_disarm_kprobe(p); + + /* Can we remove the kprobe in the middle of kprobe handling? */ + if (p->ainsn.t1_addr) { + *(p->ainsn.t1_addr) = p->ainsn.t1_opcode; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t1_addr = NULL; + } + + if (p->ainsn.t2_addr) { + *(p->ainsn.t2_addr) = p->ainsn.t2_opcode; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t2_addr = NULL; + } +} + +static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb) +{ + kcb->prev_kprobe.kp = kprobe_running(); + kcb->prev_kprobe.status = kcb->kprobe_status; +} + +static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb) +{ + __get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp; + kcb->kprobe_status = kcb->prev_kprobe.status; +} + +static inline void __kprobes set_current_kprobe(struct kprobe *p) +{ + __get_cpu_var(current_kprobe) = p; +} + +static void __kprobes resume_execution(struct kprobe *p, unsigned long addr, + struct pt_regs *regs) +{ + /* Remove the trap instructions inserted for single step and + * restore the original instructions + */ + if (p->ainsn.t1_addr) { + *(p->ainsn.t1_addr) = p->ainsn.t1_opcode; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t1_addr = NULL; + } + + if (p->ainsn.t2_addr) { + *(p->ainsn.t2_addr) = p->ainsn.t2_opcode; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t2_addr = NULL; + } + + return; +} + +static void __kprobes setup_singlestep(struct kprobe *p, struct pt_regs *regs) +{ + unsigned long next_pc; + unsigned long tgt_if_br = 0; + int is_branch; + unsigned long bta; + + /* Copy the opcode back to the kprobe location and execute the + * instruction. Because of this we will not be able to get into the + * same kprobe until this kprobe is done + */ + *(p->addr) = p->opcode; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); + + /* Now we insert the trap at the next location after this instruction to + * single step. If it is a branch we insert the trap at possible branch + * targets + */ + + bta = regs->bta; + + if (regs->status32 & 0x40) { + /* We are in a delay slot with the branch taken */ + + next_pc = bta & ~0x01; + + if (!p->ainsn.is_short) { + if (bta & 0x01) + regs->blink += 2; + else { + /* Branch not taken */ + next_pc += 2; + + /* next pc is taken from bta after executing the + * delay slot instruction + */ + regs->bta += 2; + } + } + + is_branch = 0; + } else + is_branch = + disasm_next_pc((unsigned long)p->addr, regs, + (struct callee_regs *) current->thread.callee_reg, + &next_pc, &tgt_if_br); + + p->ainsn.t1_addr = (kprobe_opcode_t *) next_pc; + p->ainsn.t1_opcode = *(p->ainsn.t1_addr); + *(p->ainsn.t1_addr) = TRAP_S_2_INSTRUCTION; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + if (is_branch) { + p->ainsn.t2_addr = (kprobe_opcode_t *) tgt_if_br; + p->ainsn.t2_opcode = *(p->ainsn.t2_addr); + *(p->ainsn.t2_addr) = TRAP_S_2_INSTRUCTION; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + } +} + +int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs) +{ + struct kprobe *p; + struct kprobe_ctlblk *kcb; + + preempt_disable(); + + kcb = get_kprobe_ctlblk(); + p = get_kprobe((unsigned long *)addr); + + if (p) { + /* + * We have reentered the kprobe_handler, since another kprobe + * was hit while within the handler, we save the original + * kprobes and single step on the instruction of the new probe + * without calling any user handlers to avoid recursive + * kprobes. + */ + if (kprobe_running()) { + save_previous_kprobe(kcb); + set_current_kprobe(p); + kprobes_inc_nmissed_count(p); + setup_singlestep(p, regs); + kcb->kprobe_status = KPROBE_REENTER; + return 1; + } + + set_current_kprobe(p); + kcb->kprobe_status = KPROBE_HIT_ACTIVE; + + /* If we have no pre-handler or it returned 0, we continue with + * normal processing. If we have a pre-handler and it returned + * non-zero - which is expected from setjmp_pre_handler for + * jprobe, we return without single stepping and leave that to + * the break-handler which is invoked by a kprobe from + * jprobe_return + */ + if (!p->pre_handler || !p->pre_handler(p, regs)) { + setup_singlestep(p, regs); + kcb->kprobe_status = KPROBE_HIT_SS; + } + + return 1; + } else if (kprobe_running()) { + p = __get_cpu_var(current_kprobe); + if (p->break_handler && p->break_handler(p, regs)) { + setup_singlestep(p, regs); + kcb->kprobe_status = KPROBE_HIT_SS; + return 1; + } + } + + /* no_kprobe: */ + preempt_enable_no_resched(); + return 0; +} + +static int __kprobes arc_post_kprobe_handler(unsigned long addr, + struct pt_regs *regs) +{ + struct kprobe *cur = kprobe_running(); + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + + if (!cur) + return 0; + + resume_execution(cur, addr, regs); + + /* Rearm the kprobe */ + arch_arm_kprobe(cur); + + /* + * When we return from trap instruction we go to the next instruction + * We restored the actual instruction in resume_exectuiont and we to + * return to the same address and execute it + */ + regs->ret = addr; + + if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) { + kcb->kprobe_status = KPROBE_HIT_SSDONE; + cur->post_handler(cur, regs, 0); + } + + if (kcb->kprobe_status == KPROBE_REENTER) { + restore_previous_kprobe(kcb); + goto out; + } + + reset_current_kprobe(); + +out: + preempt_enable_no_resched(); + return 1; +} + +/* + * Fault can be for the instruction being single stepped or for the + * pre/post handlers in the module. + * This is applicable for applications like user probes, where we have the + * probe in user space and the handlers in the kernel + */ + +int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned long trapnr) +{ + struct kprobe *cur = kprobe_running(); + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + + switch (kcb->kprobe_status) { + case KPROBE_HIT_SS: + case KPROBE_REENTER: + /* + * We are here because the instruction being single stepped + * caused the fault. We reset the current kprobe and allow the + * exception handler as if it is regular exception. In our + * case it doesn't matter because the system will be halted + */ + resume_execution(cur, (unsigned long)cur->addr, regs); + + if (kcb->kprobe_status == KPROBE_REENTER) + restore_previous_kprobe(kcb); + else + reset_current_kprobe(); + + preempt_enable_no_resched(); + break; + + case KPROBE_HIT_ACTIVE: + case KPROBE_HIT_SSDONE: + /* + * We are here because the instructions in the pre/post handler + * caused the fault. + */ + + /* We increment the nmissed count for accounting, + * we can also use npre/npostfault count for accouting + * these specific fault cases. + */ + kprobes_inc_nmissed_count(cur); + + /* + * We come here because instructions in the pre/post + * handler caused the page_fault, this could happen + * if handler tries to access user space by + * copy_from_user(), get_user() etc. Let the + * user-specified handler try to fix it first. + */ + if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr)) + return 1; + + /* + * In case the user-specified fault handler returned zero, + * try to fix up. + */ + if (fixup_exception(regs)) + return 1; + + /* + * fixup_exception() could not handle it, + * Let do_page_fault() fix it. + */ + break; + + default: + break; + } + return 0; +} + +int __kprobes kprobe_exceptions_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + struct die_args *args = data; + unsigned long addr = args->err; + int ret = NOTIFY_DONE; + + switch (val) { + case DIE_IERR: + if (arc_kprobe_handler(addr, args->regs)) + return NOTIFY_STOP; + break; + + case DIE_TRAP: + if (arc_post_kprobe_handler(addr, args->regs)) + return NOTIFY_STOP; + break; + + default: + break; + } + + return ret; +} + +int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) +{ + struct jprobe *jp = container_of(p, struct jprobe, kp); + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + unsigned long sp_addr = regs->sp; + + kcb->jprobe_saved_regs = *regs; + memcpy(kcb->jprobes_stack, (void *)sp_addr, MIN_STACK_SIZE(sp_addr)); + regs->ret = (unsigned long)(jp->entry); + + return 1; +} + +void __kprobes jprobe_return(void) +{ + __asm__ __volatile__("unimp_s"); + return; +} + +int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) +{ + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + unsigned long sp_addr; + + *regs = kcb->jprobe_saved_regs; + sp_addr = regs->sp; + memcpy((void *)sp_addr, kcb->jprobes_stack, MIN_STACK_SIZE(sp_addr)); + preempt_enable_no_resched(); + + return 1; +} + +static void __used kretprobe_trampoline_holder(void) +{ + __asm__ __volatile__(".global kretprobe_trampoline\n" + "kretprobe_trampoline:\n" "nop\n"); +} + +void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, + struct pt_regs *regs) +{ + + ri->ret_addr = (kprobe_opcode_t *) regs->blink; + + /* Replace the return addr with trampoline addr */ + regs->blink = (unsigned long)&kretprobe_trampoline; +} + +static int __kprobes trampoline_probe_handler(struct kprobe *p, + struct pt_regs *regs) +{ + struct kretprobe_instance *ri = NULL; + struct hlist_head *head, empty_rp; + struct hlist_node *tmp; + unsigned long flags, orig_ret_address = 0; + unsigned long trampoline_address = (unsigned long)&kretprobe_trampoline; + + INIT_HLIST_HEAD(&empty_rp); + kretprobe_hash_lock(current, &head, &flags); + + /* + * It is possible to have multiple instances associated with a given + * task either because an multiple functions in the call path + * have a return probe installed on them, and/or more than one return + * return probe was registered for a target function. + * + * We can handle this because: + * - instances are always inserted at the head of the list + * - when multiple return probes are registered for the same + * function, the first instance's ret_addr will point to the + * real return address, and all the rest will point to + * kretprobe_trampoline + */ + hlist_for_each_entry_safe(ri, tmp, head, hlist) { + if (ri->task != current) + /* another task is sharing our hash bucket */ + continue; + + if (ri->rp && ri->rp->handler) + ri->rp->handler(ri, regs); + + orig_ret_address = (unsigned long)ri->ret_addr; + recycle_rp_inst(ri, &empty_rp); + + if (orig_ret_address != trampoline_address) { + /* + * This is the real return address. Any other + * instances associated with this task are for + * other calls deeper on the call stack + */ + break; + } + } + + kretprobe_assert(ri, orig_ret_address, trampoline_address); + regs->ret = orig_ret_address; + + reset_current_kprobe(); + kretprobe_hash_unlock(current, &flags); + preempt_enable_no_resched(); + + hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) { + hlist_del(&ri->hlist); + kfree(ri); + } + + /* By returning a non zero value, we are telling the kprobe handler + * that we don't want the post_handler to run + */ + return 1; +} + +static struct kprobe trampoline_p = { + .addr = (kprobe_opcode_t *) &kretprobe_trampoline, + .pre_handler = trampoline_probe_handler +}; + +int __init arch_init_kprobes(void) +{ + /* Registering the trampoline code for the kret probe */ + return register_kprobe(&trampoline_p); +} + +int __kprobes arch_trampoline_kprobe(struct kprobe *p) +{ + if (p->addr == (kprobe_opcode_t *) &kretprobe_trampoline) + return 1; + + return 0; +} + +void trap_is_kprobe(unsigned long cause, unsigned long address, + struct pt_regs *regs) +{ + notify_die(DIE_TRAP, "kprobe_trap", regs, address, cause, SIGTRAP); +} diff --git a/arch/arc/kernel/module.c b/arch/arc/kernel/module.c new file mode 100644 index 00000000000..cdd359352c0 --- /dev/null +++ b/arch/arc/kernel/module.c @@ -0,0 +1,145 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/moduleloader.h> +#include <linux/kernel.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <asm/unwind.h> + +static inline void arc_write_me(unsigned short *addr, unsigned long value) +{ + *addr = (value & 0xffff0000) >> 16; + *(addr + 1) = (value & 0xffff); +} + +/* ARC specific section quirks - before relocation loop in generic loader + * + * For dwarf unwinding out of modules, this needs to + * 1. Ensure the .debug_frame is allocatable (ARC Linker bug: despite + * -fasynchronous-unwind-tables it doesn't). + * 2. Since we are iterating thru sec hdr tbl anyways, make a note of + * the exact section index, for later use. + */ +int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + char *secstr, struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + int i; + + mod->arch.unw_sec_idx = 0; + mod->arch.unw_info = NULL; + + for (i = 1; i < hdr->e_shnum; i++) { + if (strcmp(secstr+sechdrs[i].sh_name, ".debug_frame") == 0) { + sechdrs[i].sh_flags |= SHF_ALLOC; + mod->arch.unw_sec_idx = i; + break; + } + } +#endif + return 0; +} + +void module_arch_cleanup(struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + if (mod->arch.unw_info) + unwind_remove_table(mod->arch.unw_info, 0); +#endif +} + +int apply_relocate_add(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, /* sec index for sym tbl */ + unsigned int relsec, /* sec index for relo sec */ + struct module *module) +{ + int i, n; + Elf32_Rela *rel_entry = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym_entry, *sym_sec; + Elf32_Addr relocation; + Elf32_Addr location; + Elf32_Addr sec_to_patch; + int relo_type; + + sec_to_patch = sechdrs[sechdrs[relsec].sh_info].sh_addr; + sym_sec = (Elf32_Sym *) sechdrs[symindex].sh_addr; + n = sechdrs[relsec].sh_size / sizeof(*rel_entry); + + pr_debug("\n========== Module Sym reloc ===========================\n"); + pr_debug("Section to fixup %x\n", sec_to_patch); + pr_debug("=========================================================\n"); + pr_debug("rela->r_off | rela->addend | sym->st_value | ADDR | VALUE\n"); + pr_debug("=========================================================\n"); + + /* Loop thru entries in relocation section */ + for (i = 0; i < n; i++) { + + /* This is where to make the change */ + location = sec_to_patch + rel_entry[i].r_offset; + + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + sym_entry = sym_sec + ELF32_R_SYM(rel_entry[i].r_info); + + relocation = sym_entry->st_value + rel_entry[i].r_addend; + + pr_debug("\t%x\t\t%x\t\t%x %x %x [%s]\n", + rel_entry[i].r_offset, rel_entry[i].r_addend, + sym_entry->st_value, location, relocation, + strtab + sym_entry->st_name); + + /* This assumes modules are built with -mlong-calls + * so any branches/jumps are absolute 32 bit jmps + * global data access again is abs 32 bit. + * Both of these are handled by same relocation type + */ + relo_type = ELF32_R_TYPE(rel_entry[i].r_info); + + if (likely(R_ARC_32_ME == relo_type)) + arc_write_me((unsigned short *)location, relocation); + else if (R_ARC_32 == relo_type) + *((Elf32_Addr *) location) = relocation; + else + goto relo_err; + + } + return 0; + +relo_err: + pr_err("%s: unknown relocation: %u\n", + module->name, ELF32_R_TYPE(rel_entry[i].r_info)); + return -ENOEXEC; + +} + +/* Just before lift off: After sections have been relocated, we add the + * dwarf section to unwinder table pool + * This couldn't be done in module_frob_arch_sections() because + * relocations had not been applied by then + */ +int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + void *unw; + int unwsec = mod->arch.unw_sec_idx; + + if (unwsec) { + unw = unwind_add_table(mod, (void *)sechdrs[unwsec].sh_addr, + sechdrs[unwsec].sh_size); + mod->arch.unw_info = unw; + } +#endif + return 0; +} diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c new file mode 100644 index 00000000000..0a7531d9929 --- /dev/null +++ b/arch/arc/kernel/process.c @@ -0,0 +1,235 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Amit Bhor, Kanika Nema: Codito Technologies 2004 + */ + +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/fs.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/elf.h> +#include <linux/tick.h> + +SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr) +{ + task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr; + return 0; +} + +/* + * We return the user space TLS data ptr as sys-call return code + * Ideally it should be copy to user. + * However we can cheat by the fact that some sys-calls do return + * absurdly high values + * Since the tls dat aptr is not going to be in range of 0xFFFF_xxxx + * it won't be considered a sys-call error + * and it will be loads better than copy-to-user, which is a definite + * D-TLB Miss + */ +SYSCALL_DEFINE0(arc_gettls) +{ + return task_thread_info(current)->thr_ptr; +} + +static inline void arch_idle(void) +{ + /* sleep, but enable all interrupts before committing */ + __asm__("sleep 0x3"); +} + +void cpu_idle(void) +{ + /* Since we SLEEP in idle loop, TIF_POLLING_NRFLAG can't be set */ + + /* endless idle loop with no priority at all */ + while (1) { + tick_nohz_idle_enter(); + rcu_idle_enter(); + +doze: + local_irq_disable(); + if (!need_resched()) { + arch_idle(); + goto doze; + } else { + local_irq_enable(); + } + + rcu_idle_exit(); + tick_nohz_idle_exit(); + + schedule_preempt_disabled(); + } +} + +asmlinkage void ret_from_fork(void); + +/* Layout of Child kernel mode stack as setup at the end of this function is + * + * | ... | + * | ... | + * | unused | + * | | + * ------------------ <==== top of Stack (thread.ksp) + * | UNUSED 1 word| + * ------------------ + * | r25 | + * ~ ~ + * | --to-- | (CALLEE Regs of user mode) + * | r13 | + * ------------------ + * | fp | + * | blink | @ret_from_fork + * ------------------ + * | | + * ~ ~ + * ~ ~ + * | | + * ------------------ + * | r12 | + * ~ ~ + * | --to-- | (scratch Regs of user mode) + * | r0 | + * ------------------ + * | UNUSED 1 word| + * ------------------ <===== END of PAGE + */ +int copy_thread(unsigned long clone_flags, + unsigned long usp, unsigned long arg, + struct task_struct *p) +{ + struct pt_regs *c_regs; /* child's pt_regs */ + unsigned long *childksp; /* to unwind out of __switch_to() */ + struct callee_regs *c_callee; /* child's callee regs */ + struct callee_regs *parent_callee; /* paren't callee */ + struct pt_regs *regs = current_pt_regs(); + + /* Mark the specific anchors to begin with (see pic above) */ + c_regs = task_pt_regs(p); + childksp = (unsigned long *)c_regs - 2; /* 2 words for FP/BLINK */ + c_callee = ((struct callee_regs *)childksp) - 1; + + /* + * __switch_to() uses thread.ksp to start unwinding stack + * For kernel threads we don't need to create callee regs, the + * stack layout nevertheless needs to remain the same. + * Also, since __switch_to anyways unwinds callee regs, we use + * this to populate kernel thread entry-pt/args into callee regs, + * so that ret_from_kernel_thread() becomes simpler. + */ + p->thread.ksp = (unsigned long)c_callee; /* THREAD_KSP */ + + /* __switch_to expects FP(0), BLINK(return addr) at top */ + childksp[0] = 0; /* fp */ + childksp[1] = (unsigned long)ret_from_fork; /* blink */ + + if (unlikely(p->flags & PF_KTHREAD)) { + memset(c_regs, 0, sizeof(struct pt_regs)); + + c_callee->r13 = arg; /* argument to kernel thread */ + c_callee->r14 = usp; /* function */ + + return 0; + } + + /*--------- User Task Only --------------*/ + + /* __switch_to expects FP(0), BLINK(return addr) at top of stack */ + childksp[0] = 0; /* for POP fp */ + childksp[1] = (unsigned long)ret_from_fork; /* for POP blink */ + + /* Copy parents pt regs on child's kernel mode stack */ + *c_regs = *regs; + + if (usp) + c_regs->sp = usp; + + c_regs->r0 = 0; /* fork returns 0 in child */ + + parent_callee = ((struct callee_regs *)regs) - 1; + *c_callee = *parent_callee; + + if (unlikely(clone_flags & CLONE_SETTLS)) { + /* + * set task's userland tls data ptr from 4th arg + * clone C-lib call is difft from clone sys-call + */ + task_thread_info(p)->thr_ptr = regs->r3; + } else { + /* Normal fork case: set parent's TLS ptr in child */ + task_thread_info(p)->thr_ptr = + task_thread_info(current)->thr_ptr; + } + + return 0; +} + +/* + * Some archs flush debug and FPU info here + */ +void flush_thread(void) +{ +} + +/* + * Free any architecture-specific thread data structures, etc. + */ +void exit_thread(void) +{ +} + +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) +{ + return 0; +} + +/* + * API: expected by schedular Code: If thread is sleeping where is that. + * What is this good for? it will be always the scheduler or ret_from_fork. + * So we hard code that anyways. + */ +unsigned long thread_saved_pc(struct task_struct *t) +{ + struct pt_regs *regs = task_pt_regs(t); + unsigned long blink = 0; + + /* + * If the thread being queried for in not itself calling this, then it + * implies it is not executing, which in turn implies it is sleeping, + * which in turn implies it got switched OUT by the schedular. + * In that case, it's kernel mode blink can reliably retrieved as per + * the picture above (right above pt_regs). + */ + if (t != current && t->state != TASK_RUNNING) + blink = *((unsigned int *)regs - 1); + + return blink; +} + +int elf_check_arch(const struct elf32_hdr *x) +{ + unsigned int eflags; + + if (x->e_machine != EM_ARCOMPACT) + return 0; + + eflags = x->e_flags; + if ((eflags & EF_ARC_OSABI_MSK) < EF_ARC_OSABI_CURRENT) { + pr_err("ABI mismatch - you need newer toolchain\n"); + force_sigsegv(SIGSEGV, current); + return 0; + } + + return 1; +} +EXPORT_SYMBOL(elf_check_arch); diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c new file mode 100644 index 00000000000..c6a81c58d0f --- /dev/null +++ b/arch/arc/kernel/ptrace.c @@ -0,0 +1,158 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/ptrace.h> +#include <linux/tracehook.h> +#include <linux/regset.h> +#include <linux/unistd.h> +#include <linux/elf.h> + +static struct callee_regs *task_callee_regs(struct task_struct *tsk) +{ + struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg; + return tmp; +} + +static int genregs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + const struct pt_regs *ptregs = task_pt_regs(target); + const struct callee_regs *cregs = task_callee_regs(target); + int ret = 0; + unsigned int stop_pc_val; + +#define REG_O_CHUNK(START, END, PTR) \ + if (!ret) \ + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \ + offsetof(struct user_regs_struct, START), \ + offsetof(struct user_regs_struct, END)); + +#define REG_O_ONE(LOC, PTR) \ + if (!ret) \ + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \ + offsetof(struct user_regs_struct, LOC), \ + offsetof(struct user_regs_struct, LOC) + 4); + + REG_O_CHUNK(scratch, callee, ptregs); + REG_O_CHUNK(callee, efa, cregs); + REG_O_CHUNK(efa, stop_pc, &target->thread.fault_address); + + if (!ret) { + if (in_brkpt_trap(ptregs)) { + stop_pc_val = target->thread.fault_address; + pr_debug("\t\tstop_pc (brk-pt)\n"); + } else { + stop_pc_val = ptregs->ret; + pr_debug("\t\tstop_pc (others)\n"); + } + + REG_O_ONE(stop_pc, &stop_pc_val); + } + + return ret; +} + +static int genregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + const struct pt_regs *ptregs = task_pt_regs(target); + const struct callee_regs *cregs = task_callee_regs(target); + int ret = 0; + +#define REG_IN_CHUNK(FIRST, NEXT, PTR) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), \ + offsetof(struct user_regs_struct, FIRST), \ + offsetof(struct user_regs_struct, NEXT)); + +#define REG_IN_ONE(LOC, PTR) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), \ + offsetof(struct user_regs_struct, LOC), \ + offsetof(struct user_regs_struct, LOC) + 4); + +#define REG_IGNORE_ONE(LOC) \ + if (!ret) \ + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \ + offsetof(struct user_regs_struct, LOC), \ + offsetof(struct user_regs_struct, LOC) + 4); + + /* TBD: disallow updates to STATUS32, orig_r8 etc*/ + REG_IN_CHUNK(scratch, callee, ptregs); /* pt_regs[bta..orig_r8] */ + REG_IN_CHUNK(callee, efa, cregs); /* callee_regs[r25..r13] */ + REG_IGNORE_ONE(efa); /* efa update invalid */ + REG_IN_ONE(stop_pc, &ptregs->ret); /* stop_pc: PC update */ + + return ret; +} + +enum arc_getset { + REGSET_GENERAL, +}; + +static const struct user_regset arc_regsets[] = { + [REGSET_GENERAL] = { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(unsigned long), + .align = sizeof(unsigned long), + .get = genregs_get, + .set = genregs_set, + } +}; + +static const struct user_regset_view user_arc_view = { + .name = UTS_MACHINE, + .e_machine = EM_ARCOMPACT, + .regsets = arc_regsets, + .n = ARRAY_SIZE(arc_regsets) +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_arc_view; +} + +void ptrace_disable(struct task_struct *child) +{ +} + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int ret = -EIO; + + pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data); + + switch (request) { + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +} + +asmlinkage int syscall_trace_entry(struct pt_regs *regs) +{ + if (tracehook_report_syscall_entry(regs)) + return ULONG_MAX; + + return regs->r8; +} + +asmlinkage void syscall_trace_exit(struct pt_regs *regs) +{ + tracehook_report_syscall_exit(regs, 0); +} diff --git a/arch/arc/kernel/reset.c b/arch/arc/kernel/reset.c new file mode 100644 index 00000000000..e227a2b1c94 --- /dev/null +++ b/arch/arc/kernel/reset.c @@ -0,0 +1,33 @@ +/* + * Copyright (C) 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/printk.h> +#include <linux/reboot.h> +#include <linux/pm.h> + +void machine_halt(void) +{ + /* Halt the processor */ + __asm__ __volatile__("flag 1\n"); +} + +void machine_restart(char *__unused) +{ + /* Soft reset : jump to reset vector */ + pr_info("Put your restart handler here\n"); + machine_halt(); +} + +void machine_power_off(void) +{ + /* FIXME :: power off ??? */ + machine_halt(); +} + +void (*pm_power_off) (void) = NULL; diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c new file mode 100644 index 00000000000..dc0f968dae0 --- /dev/null +++ b/arch/arc/kernel/setup.c @@ -0,0 +1,473 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/seq_file.h> +#include <linux/fs.h> +#include <linux/delay.h> +#include <linux/root_dev.h> +#include <linux/console.h> +#include <linux/module.h> +#include <linux/cpu.h> +#include <linux/of_fdt.h> +#include <asm/sections.h> +#include <asm/arcregs.h> +#include <asm/tlb.h> +#include <asm/cache.h> +#include <asm/setup.h> +#include <asm/page.h> +#include <asm/irq.h> +#include <asm/arcregs.h> +#include <asm/prom.h> +#include <asm/unwind.h> +#include <asm/clk.h> +#include <asm/mach_desc.h> + +#define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x)) + +int running_on_hw = 1; /* vs. on ISS */ + +char __initdata command_line[COMMAND_LINE_SIZE]; +struct machine_desc *machine_desc __initdata; + +struct task_struct *_current_task[NR_CPUS]; /* For stack switching */ + +struct cpuinfo_arc cpuinfo_arc700[NR_CPUS]; + + +void __init read_arc_build_cfg_regs(void) +{ + struct bcr_perip uncached_space; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + FIX_PTR(cpu); + + READ_BCR(AUX_IDENTITY, cpu->core); + + cpu->timers = read_aux_reg(ARC_REG_TIMERS_BCR); + + cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE); + if (cpu->vec_base == 0) + cpu->vec_base = (unsigned int)_int_vec_base_lds; + + READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space); + cpu->uncached_base = uncached_space.start << 24; + + cpu->extn.mul = read_aux_reg(ARC_REG_MUL_BCR); + cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR); + cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR); + cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR); + cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR); + READ_BCR(ARC_REG_MAC_BCR, cpu->extn_mac_mul); + + cpu->extn.ext_arith = read_aux_reg(ARC_REG_EXTARITH_BCR); + cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR); + + /* Note that we read the CCM BCRs independent of kernel config + * This is to catch the cases where user doesn't know that + * CCMs are present in hardware build + */ + { + struct bcr_iccm iccm; + struct bcr_dccm dccm; + struct bcr_dccm_base dccm_base; + unsigned int bcr_32bit_val; + + bcr_32bit_val = read_aux_reg(ARC_REG_ICCM_BCR); + if (bcr_32bit_val) { + iccm = *((struct bcr_iccm *)&bcr_32bit_val); + cpu->iccm.base_addr = iccm.base << 16; + cpu->iccm.sz = 0x2000 << (iccm.sz - 1); + } + + bcr_32bit_val = read_aux_reg(ARC_REG_DCCM_BCR); + if (bcr_32bit_val) { + dccm = *((struct bcr_dccm *)&bcr_32bit_val); + cpu->dccm.sz = 0x800 << (dccm.sz); + + READ_BCR(ARC_REG_DCCMBASE_BCR, dccm_base); + cpu->dccm.base_addr = dccm_base.addr << 8; + } + } + + READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem); + + read_decode_mmu_bcr(); + read_decode_cache_bcr(); + + READ_BCR(ARC_REG_FP_BCR, cpu->fp); + READ_BCR(ARC_REG_DPFP_BCR, cpu->dpfp); +} + +static const struct cpuinfo_data arc_cpu_tbl[] = { + { {0x10, "ARCTangent A5"}, 0x1F}, + { {0x20, "ARC 600" }, 0x2F}, + { {0x30, "ARC 700" }, 0x33}, + { {0x34, "ARC 700 R4.10"}, 0x34}, + { {0x00, NULL } } +}; + +char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len) +{ + int n = 0; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + struct bcr_identity *core = &cpu->core; + const struct cpuinfo_data *tbl; + int be = 0; +#ifdef CONFIG_CPU_BIG_ENDIAN + be = 1; +#endif + FIX_PTR(cpu); + + n += scnprintf(buf + n, len - n, + "\nARC IDENTITY\t: Family [%#02x]" + " Cpu-id [%#02x] Chip-id [%#4x]\n", + core->family, core->cpu_id, + core->chip_id); + + for (tbl = &arc_cpu_tbl[0]; tbl->info.id != 0; tbl++) { + if ((core->family >= tbl->info.id) && + (core->family <= tbl->up_range)) { + n += scnprintf(buf + n, len - n, + "processor\t: %s %s\n", + tbl->info.str, + be ? "[Big Endian]" : ""); + break; + } + } + + if (tbl->info.id == 0) + n += scnprintf(buf + n, len - n, "UNKNOWN ARC Processor\n"); + + n += scnprintf(buf + n, len - n, "CPU speed\t: %u.%02u Mhz\n", + (unsigned int)(arc_get_core_freq() / 1000000), + (unsigned int)(arc_get_core_freq() / 10000) % 100); + + n += scnprintf(buf + n, len - n, "Timers\t\t: %s %s\n", + (cpu->timers & 0x200) ? "TIMER1" : "", + (cpu->timers & 0x100) ? "TIMER0" : ""); + + n += scnprintf(buf + n, len - n, "Vect Tbl Base\t: %#x\n", + cpu->vec_base); + + n += scnprintf(buf + n, len - n, "UNCACHED Base\t: %#x\n", + cpu->uncached_base); + + return buf; +} + +static const struct id_to_str mul_type_nm[] = { + { 0x0, "N/A"}, + { 0x1, "32x32 (spl Result Reg)" }, + { 0x2, "32x32 (ANY Result Reg)" } +}; + +static const struct id_to_str mac_mul_nm[] = { + {0x0, "N/A"}, + {0x1, "N/A"}, + {0x2, "Dual 16 x 16"}, + {0x3, "N/A"}, + {0x4, "32x16"}, + {0x5, "N/A"}, + {0x6, "Dual 16x16 and 32x16"} +}; + +char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len) +{ + int n = 0; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + + FIX_PTR(cpu); +#define IS_AVAIL1(var, str) ((var) ? str : "") +#define IS_AVAIL2(var, str) ((var == 0x2) ? str : "") +#define IS_USED(var) ((var) ? "(in-use)" : "(not used)") + + n += scnprintf(buf + n, len - n, + "Extn [700-Base]\t: %s %s %s %s %s %s\n", + IS_AVAIL2(cpu->extn.norm, "norm,"), + IS_AVAIL2(cpu->extn.barrel, "barrel-shift,"), + IS_AVAIL1(cpu->extn.swap, "swap,"), + IS_AVAIL2(cpu->extn.minmax, "minmax,"), + IS_AVAIL1(cpu->extn.crc, "crc,"), + IS_AVAIL2(cpu->extn.ext_arith, "ext-arith")); + + n += scnprintf(buf + n, len - n, "Extn [700-MPY]\t: %s", + mul_type_nm[cpu->extn.mul].str); + + n += scnprintf(buf + n, len - n, " MAC MPY: %s\n", + mac_mul_nm[cpu->extn_mac_mul.type].str); + + if (cpu->core.family == 0x34) { + n += scnprintf(buf + n, len - n, + "Extn [700-4.10]\t: LLOCK/SCOND %s, SWAPE %s, RTSC %s\n", + IS_USED(__CONFIG_ARC_HAS_LLSC_VAL), + IS_USED(__CONFIG_ARC_HAS_SWAPE_VAL), + IS_USED(__CONFIG_ARC_HAS_RTSC_VAL)); + } + + n += scnprintf(buf + n, len - n, "Extn [CCM]\t: %s", + !(cpu->dccm.sz || cpu->iccm.sz) ? "N/A" : ""); + + if (cpu->dccm.sz) + n += scnprintf(buf + n, len - n, "DCCM: @ %x, %d KB ", + cpu->dccm.base_addr, TO_KB(cpu->dccm.sz)); + + if (cpu->iccm.sz) + n += scnprintf(buf + n, len - n, "ICCM: @ %x, %d KB", + cpu->iccm.base_addr, TO_KB(cpu->iccm.sz)); + + n += scnprintf(buf + n, len - n, "\nExtn [FPU]\t: %s", + !(cpu->fp.ver || cpu->dpfp.ver) ? "N/A" : ""); + + if (cpu->fp.ver) + n += scnprintf(buf + n, len - n, "SP [v%d] %s", + cpu->fp.ver, cpu->fp.fast ? "(fast)" : ""); + + if (cpu->dpfp.ver) + n += scnprintf(buf + n, len - n, "DP [v%d] %s", + cpu->dpfp.ver, cpu->dpfp.fast ? "(fast)" : ""); + + n += scnprintf(buf + n, len - n, "\n"); + +#ifdef _ASM_GENERIC_UNISTD_H + n += scnprintf(buf + n, len - n, + "OS ABI [v2]\t: asm-generic/{unistd,stat,fcntl}\n"); +#endif + + return buf; +} + +void __init arc_chk_ccms(void) +{ +#if defined(CONFIG_ARC_HAS_DCCM) || defined(CONFIG_ARC_HAS_ICCM) + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + +#ifdef CONFIG_ARC_HAS_DCCM + /* + * DCCM can be arbit placed in hardware. + * Make sure it's placement/sz matches what Linux is built with + */ + if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr) + panic("Linux built with incorrect DCCM Base address\n"); + + if (CONFIG_ARC_DCCM_SZ != cpu->dccm.sz) + panic("Linux built with incorrect DCCM Size\n"); +#endif + +#ifdef CONFIG_ARC_HAS_ICCM + if (CONFIG_ARC_ICCM_SZ != cpu->iccm.sz) + panic("Linux built with incorrect ICCM Size\n"); +#endif +#endif +} + +/* + * Ensure that FP hardware and kernel config match + * -If hardware contains DPFP, kernel needs to save/restore FPU state + * across context switches + * -If hardware lacks DPFP, but kernel configured to save FPU state then + * kernel trying to access non-existant DPFP regs will crash + * + * We only check for Dbl precision Floating Point, because only DPFP + * hardware has dedicated regs which need to be saved/restored on ctx-sw + * (Single Precision uses core regs), thus kernel is kind of oblivious to it + */ +void __init arc_chk_fpu(void) +{ + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + + if (cpu->dpfp.ver) { +#ifndef CONFIG_ARC_FPU_SAVE_RESTORE + pr_warn("DPFP support broken in this kernel...\n"); +#endif + } else { +#ifdef CONFIG_ARC_FPU_SAVE_RESTORE + panic("H/w lacks DPFP support, apps won't work\n"); +#endif + } +} + +/* + * Initialize and setup the processor core + * This is called by all the CPUs thus should not do special case stuff + * such as only for boot CPU etc + */ + +void __init setup_processor(void) +{ + char str[512]; + int cpu_id = smp_processor_id(); + + read_arc_build_cfg_regs(); + arc_init_IRQ(); + + printk(arc_cpu_mumbojumbo(cpu_id, str, sizeof(str))); + + arc_mmu_init(); + arc_cache_init(); + arc_chk_ccms(); + + printk(arc_extn_mumbojumbo(cpu_id, str, sizeof(str))); + +#ifdef CONFIG_SMP + printk(arc_platform_smp_cpuinfo()); +#endif + + arc_chk_fpu(); +} + +void __init setup_arch(char **cmdline_p) +{ +#ifdef CONFIG_CMDLINE_UBOOT + /* Make sure that a whitespace is inserted before */ + strlcat(command_line, " ", sizeof(command_line)); +#endif + /* + * Append .config cmdline to base command line, which might already + * contain u-boot "bootargs" (handled by head.S, if so configured) + */ + strlcat(command_line, CONFIG_CMDLINE, sizeof(command_line)); + + /* Save unparsed command line copy for /proc/cmdline */ + strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); + *cmdline_p = command_line; + + machine_desc = setup_machine_fdt(__dtb_start); + if (!machine_desc) + panic("Embedded DT invalid\n"); + + /* To force early parsing of things like mem=xxx */ + parse_early_param(); + + /* Platform/board specific: e.g. early console registration */ + if (machine_desc->init_early) + machine_desc->init_early(); + + setup_processor(); + +#ifdef CONFIG_SMP + smp_init_cpus(); +#endif + + setup_arch_memory(); + + /* copy flat DT out of .init and then unflatten it */ + copy_devtree(); + unflatten_device_tree(); + + /* Can be issue if someone passes cmd line arg "ro" + * But that is unlikely so keeping it as it is + */ + root_mountflags &= ~MS_RDONLY; + + console_verbose(); + +#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE) + conswitchp = &dummy_con; +#endif + + arc_unwind_init(); + arc_unwind_setup(); +} + +static int __init customize_machine(void) +{ + /* Add platform devices */ + if (machine_desc->init_machine) + machine_desc->init_machine(); + + return 0; +} +arch_initcall(customize_machine); + +static int __init init_late_machine(void) +{ + if (machine_desc->init_late) + machine_desc->init_late(); + + return 0; +} +late_initcall(init_late_machine); +/* + * Get CPU information for use by the procfs. + */ + +#define cpu_to_ptr(c) ((void *)(0xFFFF0000 | (unsigned int)(c))) +#define ptr_to_cpu(p) (~0xFFFF0000UL & (unsigned int)(p)) + +static int show_cpuinfo(struct seq_file *m, void *v) +{ + char *str; + int cpu_id = ptr_to_cpu(v); + + str = (char *)__get_free_page(GFP_TEMPORARY); + if (!str) + goto done; + + seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + + seq_printf(m, "Bogo MIPS : \t%lu.%02lu\n", + loops_per_jiffy / (500000 / HZ), + (loops_per_jiffy / (5000 / HZ)) % 100); + + seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + + seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE)); + + seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE)); + +#ifdef CONFIG_SMP + seq_printf(m, arc_platform_smp_cpuinfo()); +#endif + + free_page((unsigned long)str); +done: + seq_printf(m, "\n\n"); + + return 0; +} + +static void *c_start(struct seq_file *m, loff_t *pos) +{ + /* + * Callback returns cpu-id to iterator for show routine, NULL to stop. + * However since NULL is also a valid cpu-id (0), we use a round-about + * way to pass it w/o having to kmalloc/free a 2 byte string. + * Encode cpu-id as 0xFFcccc, which is decoded by show routine. + */ + return *pos < num_possible_cpus() ? cpu_to_ptr(*pos) : NULL; +} + +static void *c_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return c_start(m, pos); +} + +static void c_stop(struct seq_file *m, void *v) +{ +} + +const struct seq_operations cpuinfo_op = { + .start = c_start, + .next = c_next, + .stop = c_stop, + .show = show_cpuinfo +}; + +static DEFINE_PER_CPU(struct cpu, cpu_topology); + +static int __init topology_init(void) +{ + int cpu; + + for_each_present_cpu(cpu) + register_cpu(&per_cpu(cpu_topology, cpu), cpu); + + return 0; +} + +subsys_initcall(topology_init); diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c new file mode 100644 index 00000000000..ee6ef2f60a2 --- /dev/null +++ b/arch/arc/kernel/signal.c @@ -0,0 +1,360 @@ +/* + * Signal Handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: Jan 2010 (Restarting of timer related syscalls) + * + * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) + * -do_signal() supports TIF_RESTORE_SIGMASK + * -do_signal() no loner needs oldset, required by OLD sys_sigsuspend + * -sys_rt_sigsuspend() now comes from generic code, so discard arch implemen + * -sys_sigsuspend() no longer needs to fudge ptregs, hence that arg removed + * -sys_sigsuspend() no longer loops for do_signal(), sets TIF_xxx and leaves + * the job to do_signal() + * + * vineetg: July 2009 + * -Modified Code to support the uClibc provided userland sigreturn stub + * to avoid kernel synthesing it on user stack at runtime, costing TLB + * probes and Cache line flushes. + * + * vineetg: July 2009 + * -In stash_usr_regs( ) and restore_usr_regs( ), save/restore of user regs + * in done in block copy rather than one word at a time. + * This saves around 2K of code and improves LMBench lat_sig <catch> + * + * rajeshwarr: Feb 2009 + * - Support for Realtime Signals + * + * vineetg: Aug 11th 2008: Bug #94183 + * -ViXS were still seeing crashes when using insmod to load drivers. + * It turned out that the code to change Execute permssions for TLB entries + * of user was not guarded for interrupts (mod_tlb_permission) + * This was cauing TLB entries to be overwritten on unrelated indexes + * + * Vineetg: July 15th 2008: Bug #94183 + * -Exception happens in Delay slot of a JMP, and before user space resumes, + * Signal is delivered (Ctrl + C) = >SIGINT. + * setup_frame( ) sets up PC,SP,BLINK to enable user space signal handler + * to run, but doesn't clear the Delay slot bit from status32. As a result, + * on resuming user mode, signal handler branches off to BTA of orig JMP + * -FIX: clear the DE bit from status32 in setup_frame( ) + * + * Rahul Trivedi, Kanika Nema: Codito Technologies 2004 + */ + +#include <linux/signal.h> +#include <linux/ptrace.h> +#include <linux/personality.h> +#include <linux/uaccess.h> +#include <linux/syscalls.h> +#include <linux/tracehook.h> +#include <asm/ucontext.h> + +struct rt_sigframe { + struct siginfo info; + struct ucontext uc; +#define MAGIC_SIGALTSTK 0x07302004 + unsigned int sigret_magic; +}; + +static int +stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs, + sigset_t *set) +{ + int err; + err = __copy_to_user(&(sf->uc.uc_mcontext.regs), regs, + sizeof(sf->uc.uc_mcontext.regs.scratch)); + err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t)); + + return err; +} + +static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf) +{ + sigset_t set; + int err; + + err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); + if (!err) + set_current_blocked(&set); + + err |= __copy_from_user(regs, &(sf->uc.uc_mcontext.regs), + sizeof(sf->uc.uc_mcontext.regs.scratch)); + + return err; +} + +static inline int is_do_ss_needed(unsigned int magic) +{ + if (MAGIC_SIGALTSTK == magic) + return 1; + else + return 0; +} + +SYSCALL_DEFINE0(rt_sigreturn) +{ + struct rt_sigframe __user *sf; + unsigned int magic; + int err; + struct pt_regs *regs = current_pt_regs(); + + /* Always make any pending restarted system calls return -EINTR */ + current_thread_info()->restart_block.fn = do_no_restart_syscall; + + /* Since we stacked the signal on a word boundary, + * then 'sp' should be word aligned here. If it's + * not, then the user is trying to mess with us. + */ + if (regs->sp & 3) + goto badframe; + + sf = (struct rt_sigframe __force __user *)(regs->sp); + + if (!access_ok(VERIFY_READ, sf, sizeof(*sf))) + goto badframe; + + err = restore_usr_regs(regs, sf); + err |= __get_user(magic, &sf->sigret_magic); + if (err) + goto badframe; + + if (unlikely(is_do_ss_needed(magic))) + if (restore_altstack(&sf->uc.uc_stack)) + goto badframe; + + /* Don't restart from sigreturn */ + syscall_wont_restart(regs); + + return regs->r0; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +/* + * Determine which stack to use.. + */ +static inline void __user *get_sigframe(struct k_sigaction *ka, + struct pt_regs *regs, + unsigned long framesize) +{ + unsigned long sp = regs->sp; + void __user *frame; + + /* This is the X/Open sanctioned signal stack switching */ + if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp)) + sp = current->sas_ss_sp + current->sas_ss_size; + + /* No matter what happens, 'sp' must be word + * aligned otherwise nasty things could happen + */ + + /* ATPCS B01 mandates 8-byte alignment */ + frame = (void __user *)((sp - framesize) & ~7); + + /* Check that we can actually write to the signal frame */ + if (!access_ok(VERIFY_WRITE, frame, framesize)) + frame = NULL; + + return frame; +} + +/* + * translate the signal + */ +static inline int map_sig(int sig) +{ + struct thread_info *thread = current_thread_info(); + if (thread->exec_domain && thread->exec_domain->signal_invmap + && sig < 32) + sig = thread->exec_domain->signal_invmap[sig]; + return sig; +} + +static int +setup_rt_frame(int signo, struct k_sigaction *ka, siginfo_t *info, + sigset_t *set, struct pt_regs *regs) +{ + struct rt_sigframe __user *sf; + unsigned int magic = 0; + int err = 0; + + sf = get_sigframe(ka, regs, sizeof(struct rt_sigframe)); + if (!sf) + return 1; + + /* + * SA_SIGINFO requires 3 args to signal handler: + * #1: sig-no (common to any handler) + * #2: struct siginfo + * #3: struct ucontext (completely populated) + */ + if (unlikely(ka->sa.sa_flags & SA_SIGINFO)) { + err |= copy_siginfo_to_user(&sf->info, info); + err |= __put_user(0, &sf->uc.uc_flags); + err |= __put_user(NULL, &sf->uc.uc_link); + err |= __save_altstack(&sf->uc.uc_stack, regs->sp); + + /* setup args 2 and 3 for user mode handler */ + regs->r1 = (unsigned long)&sf->info; + regs->r2 = (unsigned long)&sf->uc; + + /* + * small optim to avoid unconditonally calling do_sigaltstack + * in sigreturn path, now that we only have rt_sigreturn + */ + magic = MAGIC_SIGALTSTK; + } + + /* + * w/o SA_SIGINFO, struct ucontext is partially populated (only + * uc_mcontext/uc_sigmask) for kernel's normal user state preservation + * during signal handler execution. This works for SA_SIGINFO as well + * although the semantics are now overloaded (the same reg state can be + * inspected by userland: but are they allowed to fiddle with it ? + */ + err |= stash_usr_regs(sf, regs, set); + err |= __put_user(magic, &sf->sigret_magic); + if (err) + return err; + + /* #1 arg to the user Signal handler */ + regs->r0 = map_sig(signo); + + /* setup PC of user space signal handler */ + regs->ret = (unsigned long)ka->sa.sa_handler; + + /* + * handler returns using sigreturn stub provided already by userpsace + */ + BUG_ON(!(ka->sa.sa_flags & SA_RESTORER)); + regs->blink = (unsigned long)ka->sa.sa_restorer; + + /* User Stack for signal handler will be above the frame just carved */ + regs->sp = (unsigned long)sf; + + /* + * Bug 94183, Clear the DE bit, so that when signal handler + * starts to run, it doesn't use BTA + */ + regs->status32 &= ~STATUS_DE_MASK; + regs->status32 |= STATUS_L_MASK; + + return err; +} + +static void arc_restart_syscall(struct k_sigaction *ka, struct pt_regs *regs) +{ + switch (regs->r0) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + /* + * ERESTARTNOHAND means that the syscall should + * only be restarted if there was no handler for + * the signal, and since we only get here if there + * is a handler, we don't restart + */ + regs->r0 = -EINTR; /* ERESTART_xxx is internal */ + break; + + case -ERESTARTSYS: + /* + * ERESTARTSYS means to restart the syscall if + * there is no handler or the handler was + * registered with SA_RESTART + */ + if (!(ka->sa.sa_flags & SA_RESTART)) { + regs->r0 = -EINTR; + break; + } + /* fallthrough */ + + case -ERESTARTNOINTR: + /* + * ERESTARTNOINTR means that the syscall should + * be called again after the signal handler returns. + * Setup reg state just as it was before doing the trap + * r0 has been clobbered with sys call ret code thus it + * needs to be reloaded with orig first arg to syscall + * in orig_r0. Rest of relevant reg-file: + * r8 (syscall num) and (r1 - r7) will be reset to + * their orig user space value when we ret from kernel + */ + regs->r0 = regs->orig_r0; + regs->ret -= 4; + break; + } +} + +/* + * OK, we're invoking a handler + */ +static void +handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, + struct pt_regs *regs) +{ + sigset_t *oldset = sigmask_to_save(); + int ret; + + /* Set up the stack frame */ + ret = setup_rt_frame(sig, ka, info, oldset, regs); + + if (ret) + force_sigsegv(sig, current); + else + signal_delivered(sig, info, ka, regs, 0); +} + +void do_signal(struct pt_regs *regs) +{ + struct k_sigaction ka; + siginfo_t info; + int signr; + int restart_scall; + + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + + restart_scall = in_syscall(regs) && syscall_restartable(regs); + + if (signr > 0) { + if (restart_scall) { + arc_restart_syscall(&ka, regs); + syscall_wont_restart(regs); /* No more restarts */ + } + handle_signal(signr, &ka, &info, regs); + return; + } + + if (restart_scall) { + /* No handler for syscall: restart it */ + if (regs->r0 == -ERESTARTNOHAND || + regs->r0 == -ERESTARTSYS || regs->r0 == -ERESTARTNOINTR) { + regs->r0 = regs->orig_r0; + regs->ret -= 4; + } else if (regs->r0 == -ERESTART_RESTARTBLOCK) { + regs->r8 = __NR_restart_syscall; + regs->ret -= 4; + } + syscall_wont_restart(regs); /* No more restarts */ + } + + /* If there's no signal to deliver, restore the saved sigmask back */ + restore_saved_sigmask(); +} + +void do_notify_resume(struct pt_regs *regs) +{ + /* + * ASM glue gaurantees that this is only called when returning to + * user mode + */ + if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) + tracehook_notify_resume(regs); +} diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c new file mode 100644 index 00000000000..3af3e06dcf0 --- /dev/null +++ b/arch/arc/kernel/smp.c @@ -0,0 +1,332 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * RajeshwarR: Dec 11, 2007 + * -- Added support for Inter Processor Interrupts + * + * Vineetg: Nov 1st, 2007 + * -- Initial Write (Borrowed heavily from ARM) + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/profile.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/mm.h> +#include <linux/cpu.h> +#include <linux/smp.h> +#include <linux/irq.h> +#include <linux/delay.h> +#include <linux/atomic.h> +#include <linux/percpu.h> +#include <linux/cpumask.h> +#include <linux/spinlock_types.h> +#include <linux/reboot.h> +#include <asm/processor.h> +#include <asm/setup.h> +#include <asm/mach_desc.h> + +arch_spinlock_t smp_atomic_ops_lock = __ARCH_SPIN_LOCK_UNLOCKED; +arch_spinlock_t smp_bitops_lock = __ARCH_SPIN_LOCK_UNLOCKED; + +struct plat_smp_ops plat_smp_ops; + +/* XXX: per cpu ? Only needed once in early seconday boot */ +struct task_struct *secondary_idle_tsk; + +/* Called from start_kernel */ +void __init smp_prepare_boot_cpu(void) +{ +} + +/* + * Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + */ +void __init smp_init_cpus(void) +{ + unsigned int i; + + for (i = 0; i < NR_CPUS; i++) + set_cpu_possible(i, true); +} + +/* called from init ( ) => process 1 */ +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + int i; + + /* + * Initialise the present map, which describes the set of CPUs + * actually populated at the present time. + */ + for (i = 0; i < max_cpus; i++) + set_cpu_present(i, true); +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ + +} + +/* + * After power-up, a non Master CPU needs to wait for Master to kick start it + * + * The default implementation halts + * + * This relies on platform specific support allowing Master to directly set + * this CPU's PC (to be @first_lines_of_secondary() and kick start it. + * + * In lack of such h/w assist, platforms can override this function + * - make this function busy-spin on a token, eventually set by Master + * (from arc_platform_smp_wakeup_cpu()) + * - Once token is available, jump to @first_lines_of_secondary + * (using inline asm). + * + * Alert: can NOT use stack here as it has not been determined/setup for CPU. + * If it turns out to be elaborate, it's better to code it in assembly + * + */ +void __attribute__((weak)) arc_platform_smp_wait_to_boot(int cpu) +{ + /* + * As a hack for debugging - since debugger will single-step over the + * FLAG insn - wrap the halt itself it in a self loop + */ + __asm__ __volatile__( + "1: \n" + " flag 1 \n" + " b 1b \n"); +} + +const char *arc_platform_smp_cpuinfo(void) +{ + return plat_smp_ops.info; +} + +/* + * The very first "C" code executed by secondary + * Called from asm stub in head.S + * "current"/R25 already setup by low level boot code + */ +void __cpuinit start_kernel_secondary(void) +{ + struct mm_struct *mm = &init_mm; + unsigned int cpu = smp_processor_id(); + + /* MMU, Caches, Vector Table, Interrupts etc */ + setup_processor(); + + atomic_inc(&mm->mm_users); + atomic_inc(&mm->mm_count); + current->active_mm = mm; + + notify_cpu_starting(cpu); + set_cpu_online(cpu, true); + + pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu); + + if (machine_desc->init_smp) + machine_desc->init_smp(smp_processor_id()); + + arc_local_timer_setup(cpu); + + local_irq_enable(); + preempt_disable(); + cpu_idle(); +} + +/* + * Called from kernel_init( ) -> smp_init( ) - for each CPU + * + * At this point, Secondary Processor is "HALT"ed: + * -It booted, but was halted in head.S + * -It was configured to halt-on-reset + * So need to wake it up. + * + * Essential requirements being where to run from (PC) and stack (SP) +*/ +int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) +{ + unsigned long wait_till; + + secondary_idle_tsk = idle; + + pr_info("Idle Task [%d] %p", cpu, idle); + pr_info("Trying to bring up CPU%u ...\n", cpu); + + if (plat_smp_ops.cpu_kick) + plat_smp_ops.cpu_kick(cpu, + (unsigned long)first_lines_of_secondary); + + /* wait for 1 sec after kicking the secondary */ + wait_till = jiffies + HZ; + while (time_before(jiffies, wait_till)) { + if (cpu_online(cpu)) + break; + } + + if (!cpu_online(cpu)) { + pr_info("Timeout: CPU%u FAILED to comeup !!!\n", cpu); + return -1; + } + + secondary_idle_tsk = NULL; + + return 0; +} + +/* + * not supported here + */ +int __init setup_profiling_timer(unsigned int multiplier) +{ + return -EINVAL; +} + +/*****************************************************************************/ +/* Inter Processor Interrupt Handling */ +/*****************************************************************************/ + +/* + * structures for inter-processor calls + * A Collection of single bit ipi messages + * + */ + +/* + * TODO_rajesh investigate tlb message types. + * IPI Timer not needed because each ARC has an individual Interrupting Timer + */ +enum ipi_msg_type { + IPI_NOP = 0, + IPI_RESCHEDULE = 1, + IPI_CALL_FUNC, + IPI_CALL_FUNC_SINGLE, + IPI_CPU_STOP +}; + +struct ipi_data { + unsigned long bits; +}; + +static DEFINE_PER_CPU(struct ipi_data, ipi_data); + +static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg) +{ + unsigned long flags; + unsigned int cpu; + + local_irq_save(flags); + + for_each_cpu(cpu, callmap) { + struct ipi_data *ipi = &per_cpu(ipi_data, cpu); + set_bit(msg, &ipi->bits); + } + + /* Call the platform specific cross-CPU call function */ + if (plat_smp_ops.ipi_send) + plat_smp_ops.ipi_send((void *)callmap); + + local_irq_restore(flags); +} + +void smp_send_reschedule(int cpu) +{ + ipi_send_msg(cpumask_of(cpu), IPI_RESCHEDULE); +} + +void smp_send_stop(void) +{ + struct cpumask targets; + cpumask_copy(&targets, cpu_online_mask); + cpumask_clear_cpu(smp_processor_id(), &targets); + ipi_send_msg(&targets, IPI_CPU_STOP); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + ipi_send_msg(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); +} + +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + ipi_send_msg(mask, IPI_CALL_FUNC); +} + +/* + * ipi_cpu_stop - handle IPI from smp_send_stop() + */ +static void ipi_cpu_stop(unsigned int cpu) +{ + machine_halt(); +} + +static inline void __do_IPI(unsigned long *ops, struct ipi_data *ipi, int cpu) +{ + unsigned long msg = 0; + + do { + msg = find_next_bit(ops, BITS_PER_LONG, msg+1); + + switch (msg) { + case IPI_RESCHEDULE: + scheduler_ipi(); + break; + + case IPI_CALL_FUNC: + generic_smp_call_function_interrupt(); + break; + + case IPI_CALL_FUNC_SINGLE: + generic_smp_call_function_single_interrupt(); + break; + + case IPI_CPU_STOP: + ipi_cpu_stop(cpu); + break; + } + } while (msg < BITS_PER_LONG); + +} + +/* + * arch-common ISR to handle for inter-processor interrupts + * Has hooks for platform specific IPI + */ +irqreturn_t do_IPI(int irq, void *dev_id) +{ + int cpu = smp_processor_id(); + struct ipi_data *ipi = &per_cpu(ipi_data, cpu); + unsigned long ops; + + if (plat_smp_ops.ipi_clear) + plat_smp_ops.ipi_clear(cpu, irq); + + /* + * XXX: is this loop really needed + * And do we need to move ipi_clean inside + */ + while ((ops = xchg(&ipi->bits, 0)) != 0) + __do_IPI(&ops, ipi, cpu); + + return IRQ_HANDLED; +} + +/* + * API called by platform code to hookup arch-common ISR to their IPI IRQ + */ +static DEFINE_PER_CPU(int, ipi_dev); +int smp_ipi_irq_setup(int cpu, int irq) +{ + int *dev_id = &per_cpu(ipi_dev, smp_processor_id()); + return request_percpu_irq(irq, do_IPI, "IPI Interrupt", dev_id); +} diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c new file mode 100644 index 00000000000..a63ff842564 --- /dev/null +++ b/arch/arc/kernel/stacktrace.c @@ -0,0 +1,254 @@ +/* + * stacktrace.c : stacktracing APIs needed by rest of kernel + * (wrappers over ARC dwarf based unwinder) + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: aug 2009 + * -Implemented CONFIG_STACKTRACE APIs, primarily save_stack_trace_tsk( ) + * for displaying task's kernel mode call stack in /proc/<pid>/stack + * -Iterator based approach to have single copy of unwinding core and APIs + * needing unwinding, implement the logic in iterator regarding: + * = which frame onwards to start capture + * = which frame to stop capturing (wchan) + * = specifics of data structs where trace is saved(CONFIG_STACKTRACE etc) + * + * vineetg: March 2009 + * -Implemented correct versions of thread_saved_pc() and get_wchan() + * + * rajeshwarr: 2008 + * -Initial implementation + */ + +#include <linux/ptrace.h> +#include <linux/export.h> +#include <linux/stacktrace.h> +#include <linux/kallsyms.h> +#include <asm/arcregs.h> +#include <asm/unwind.h> +#include <asm/switch_to.h> + +/*------------------------------------------------------------------------- + * Unwinder Iterator + *------------------------------------------------------------------------- + */ + +#ifdef CONFIG_ARC_DW2_UNWIND + +static void seed_unwind_frame_info(struct task_struct *tsk, + struct pt_regs *regs, + struct unwind_frame_info *frame_info) +{ + if (tsk == NULL && regs == NULL) { + unsigned long fp, sp, blink, ret; + frame_info->task = current; + + __asm__ __volatile__( + "mov %0,r27\n\t" + "mov %1,r28\n\t" + "mov %2,r31\n\t" + "mov %3,r63\n\t" + : "=r"(fp), "=r"(sp), "=r"(blink), "=r"(ret) + ); + + frame_info->regs.r27 = fp; + frame_info->regs.r28 = sp; + frame_info->regs.r31 = blink; + frame_info->regs.r63 = ret; + frame_info->call_frame = 0; + } else if (regs == NULL) { + + frame_info->task = tsk; + + frame_info->regs.r27 = KSTK_FP(tsk); + frame_info->regs.r28 = KSTK_ESP(tsk); + frame_info->regs.r31 = KSTK_BLINK(tsk); + frame_info->regs.r63 = (unsigned int)__switch_to; + + /* In the prologue of __switch_to, first FP is saved on stack + * and then SP is copied to FP. Dwarf assumes cfa as FP based + * but we didn't save FP. The value retrieved above is FP's + * state in previous frame. + * As a work around for this, we unwind from __switch_to start + * and adjust SP accordingly. The other limitation is that + * __switch_to macro is dwarf rules are not generated for inline + * assembly code + */ + frame_info->regs.r27 = 0; + frame_info->regs.r28 += 64; + frame_info->call_frame = 0; + + } else { + frame_info->task = tsk; + + frame_info->regs.r27 = regs->fp; + frame_info->regs.r28 = regs->sp; + frame_info->regs.r31 = regs->blink; + frame_info->regs.r63 = regs->ret; + frame_info->call_frame = 0; + } +} + +#endif + +static noinline unsigned int +arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs, + int (*consumer_fn) (unsigned int, void *), void *arg) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + int ret = 0; + unsigned int address; + struct unwind_frame_info frame_info; + + seed_unwind_frame_info(tsk, regs, &frame_info); + + while (1) { + address = UNW_PC(&frame_info); + + if (address && __kernel_text_address(address)) { + if (consumer_fn(address, arg) == -1) + break; + } + + ret = arc_unwind(&frame_info); + + if (ret == 0) { + frame_info.regs.r63 = frame_info.regs.r31; + continue; + } else { + break; + } + } + + return address; /* return the last address it saw */ +#else + /* On ARC, only Dward based unwinder works. fp based backtracing is + * not possible (-fno-omit-frame-pointer) because of the way function + * prelogue is setup (callee regs saved and then fp set and not other + * way around + */ + pr_warn("CONFIG_ARC_DW2_UNWIND needs to be enabled\n"); + return 0; + +#endif +} + +/*------------------------------------------------------------------------- + * callbacks called by unwinder iterator to implement kernel APIs + * + * The callback can return -1 to force the iterator to stop, which by default + * keeps going till the bottom-most frame. + *------------------------------------------------------------------------- + */ + +/* Call-back which plugs into unwinding core to dump the stack in + * case of panic/OOPs/BUG etc + */ +static int __print_sym(unsigned int address, void *unused) +{ + __print_symbol(" %s\n", address); + return 0; +} + +#ifdef CONFIG_STACKTRACE + +/* Call-back which plugs into unwinding core to capture the + * traces needed by kernel on /proc/<pid>/stack + */ +static int __collect_all(unsigned int address, void *arg) +{ + struct stack_trace *trace = arg; + + if (trace->skip > 0) + trace->skip--; + else + trace->entries[trace->nr_entries++] = address; + + if (trace->nr_entries >= trace->max_entries) + return -1; + + return 0; +} + +static int __collect_all_but_sched(unsigned int address, void *arg) +{ + struct stack_trace *trace = arg; + + if (in_sched_functions(address)) + return 0; + + if (trace->skip > 0) + trace->skip--; + else + trace->entries[trace->nr_entries++] = address; + + if (trace->nr_entries >= trace->max_entries) + return -1; + + return 0; +} + +#endif + +static int __get_first_nonsched(unsigned int address, void *unused) +{ + if (in_sched_functions(address)) + return 0; + + return -1; +} + +/*------------------------------------------------------------------------- + * APIs expected by various kernel sub-systems + *------------------------------------------------------------------------- + */ + +noinline void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs) +{ + pr_info("\nStack Trace:\n"); + arc_unwind_core(tsk, regs, __print_sym, NULL); +} +EXPORT_SYMBOL(show_stacktrace); + +/* Expected by sched Code */ +void show_stack(struct task_struct *tsk, unsigned long *sp) +{ + show_stacktrace(tsk, NULL); +} + +/* Expected by Rest of kernel code */ +void dump_stack(void) +{ + show_stacktrace(NULL, NULL); +} +EXPORT_SYMBOL(dump_stack); + +/* Another API expected by schedular, shows up in "ps" as Wait Channel + * Ofcourse just returning schedule( ) would be pointless so unwind until + * the function is not in schedular code + */ +unsigned int get_wchan(struct task_struct *tsk) +{ + return arc_unwind_core(tsk, NULL, __get_first_nonsched, NULL); +} + +#ifdef CONFIG_STACKTRACE + +/* + * API required by CONFIG_STACKTRACE, CONFIG_LATENCYTOP. + * A typical use is when /proc/<pid>/stack is queried by userland + */ +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +{ + arc_unwind_core(tsk, NULL, __collect_all_but_sched, trace); +} + +void save_stack_trace(struct stack_trace *trace) +{ + arc_unwind_core(current, NULL, __collect_all, trace); +} +#endif diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c new file mode 100644 index 00000000000..f6bdd07583f --- /dev/null +++ b/arch/arc/kernel/sys.c @@ -0,0 +1,18 @@ + +#include <linux/syscalls.h> +#include <linux/signal.h> +#include <linux/unistd.h> + +#include <asm/syscalls.h> + +#define sys_clone sys_clone_wrapper +#define sys_fork sys_fork_wrapper +#define sys_vfork sys_vfork_wrapper + +#undef __SYSCALL +#define __SYSCALL(nr, call) [nr] = (call), + +void *sys_call_table[NR_syscalls] = { + [0 ... NR_syscalls-1] = sys_ni_syscall, +#include <asm/unistd.h> +}; diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c new file mode 100644 index 00000000000..f13f72807aa --- /dev/null +++ b/arch/arc/kernel/time.c @@ -0,0 +1,265 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: Jan 1011 + * -sched_clock( ) no longer jiffies based. Uses the same clocksource + * as gtod + * + * Rajeshwarr/Vineetg: Mar 2008 + * -Implemented CONFIG_GENERIC_TIME (rather deleted arch specific code) + * for arch independent gettimeofday() + * -Implemented CONFIG_GENERIC_CLOCKEVENTS as base for hrtimers + * + * Vineetg: Mar 2008: Forked off from time.c which now is time-jiff.c + */ + +/* ARC700 has two 32bit independent prog Timers: TIMER0 and TIMER1 + * Each can programmed to go from @count to @limit and optionally + * interrupt when that happens. + * A write to Control Register clears the Interrupt + * + * We've designated TIMER0 for events (clockevents) + * while TIMER1 for free running (clocksource) + * + * Newer ARC700 cores have 64bit clk fetching RTSC insn, preferred over TIMER1 + */ + +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/time.h> +#include <linux/init.h> +#include <linux/timex.h> +#include <linux/profile.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <asm/irq.h> +#include <asm/arcregs.h> +#include <asm/clk.h> +#include <asm/mach_desc.h> + +#define ARC_TIMER_MAX 0xFFFFFFFF + +/********** Clock Source Device *********/ + +#ifdef CONFIG_ARC_HAS_RTSC + +int __cpuinit arc_counter_setup(void) +{ + /* RTSC insn taps into cpu clk, needs no setup */ + + /* For SMP, only allowed if cross-core-sync, hence usable as cs */ + return 1; +} + +static cycle_t arc_counter_read(struct clocksource *cs) +{ + unsigned long flags; + union { +#ifdef CONFIG_CPU_BIG_ENDIAN + struct { u32 high, low; }; +#else + struct { u32 low, high; }; +#endif + cycle_t full; + } stamp; + + flags = arch_local_irq_save(); + + __asm__ __volatile( + " .extCoreRegister tsch, 58, r, cannot_shortcut \n" + " rtsc %0, 0 \n" + " mov %1, 0 \n" + : "=r" (stamp.low), "=r" (stamp.high)); + + arch_local_irq_restore(flags); + + return stamp.full; +} + +static struct clocksource arc_counter = { + .name = "ARC RTSC", + .rating = 300, + .read = arc_counter_read, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +#else /* !CONFIG_ARC_HAS_RTSC */ + +static bool is_usable_as_clocksource(void) +{ +#ifdef CONFIG_SMP + return 0; +#else + return 1; +#endif +} + +/* + * set 32bit TIMER1 to keep counting monotonically and wraparound + */ +int __cpuinit arc_counter_setup(void) +{ + write_aux_reg(ARC_REG_TIMER1_LIMIT, ARC_TIMER_MAX); + write_aux_reg(ARC_REG_TIMER1_CNT, 0); + write_aux_reg(ARC_REG_TIMER1_CTRL, TIMER_CTRL_NH); + + return is_usable_as_clocksource(); +} + +static cycle_t arc_counter_read(struct clocksource *cs) +{ + return (cycle_t) read_aux_reg(ARC_REG_TIMER1_CNT); +} + +static struct clocksource arc_counter = { + .name = "ARC Timer1", + .rating = 300, + .read = arc_counter_read, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +#endif + +/********** Clock Event Device *********/ + +/* + * Arm the timer to interrupt after @limit cycles + * The distinction for oneshot/periodic is done in arc_event_timer_ack() below + */ +static void arc_timer_event_setup(unsigned int limit) +{ + write_aux_reg(ARC_REG_TIMER0_LIMIT, limit); + write_aux_reg(ARC_REG_TIMER0_CNT, 0); /* start from 0 */ + + write_aux_reg(ARC_REG_TIMER0_CTRL, TIMER_CTRL_IE | TIMER_CTRL_NH); +} + +/* + * Acknowledge the interrupt (oneshot) and optionally re-arm it (periodic) + * -Any write to CTRL Reg will ack the intr (NH bit: Count when not halted) + * -Rearming is done by setting the IE bit + * + * Small optimisation: Normal code would have been + * if (irq_reenable) + * CTRL_REG = (IE | NH); + * else + * CTRL_REG = NH; + * However since IE is BIT0 we can fold the branch + */ +static void arc_timer_event_ack(unsigned int irq_reenable) +{ + write_aux_reg(ARC_REG_TIMER0_CTRL, irq_reenable | TIMER_CTRL_NH); +} + +static int arc_clkevent_set_next_event(unsigned long delta, + struct clock_event_device *dev) +{ + arc_timer_event_setup(delta); + return 0; +} + +static void arc_clkevent_set_mode(enum clock_event_mode mode, + struct clock_event_device *dev) +{ + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + arc_timer_event_setup(arc_get_core_freq() / HZ); + break; + case CLOCK_EVT_MODE_ONESHOT: + break; + default: + break; + } + + return; +} + +static DEFINE_PER_CPU(struct clock_event_device, arc_clockevent_device) = { + .name = "ARC Timer0", + .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, + .mode = CLOCK_EVT_MODE_UNUSED, + .rating = 300, + .irq = TIMER0_IRQ, /* hardwired, no need for resources */ + .set_next_event = arc_clkevent_set_next_event, + .set_mode = arc_clkevent_set_mode, +}; + +static irqreturn_t timer_irq_handler(int irq, void *dev_id) +{ + struct clock_event_device *clk = &__get_cpu_var(arc_clockevent_device); + + arc_timer_event_ack(clk->mode == CLOCK_EVT_MODE_PERIODIC); + clk->event_handler(clk); + return IRQ_HANDLED; +} + +static struct irqaction arc_timer_irq = { + .name = "Timer0 (clock-evt-dev)", + .flags = IRQF_TIMER | IRQF_PERCPU, + .handler = timer_irq_handler, +}; + +/* + * Setup the local event timer for @cpu + * N.B. weak so that some exotic ARC SoCs can completely override it + */ +void __attribute__((weak)) __cpuinit arc_local_timer_setup(unsigned int cpu) +{ + struct clock_event_device *clk = &per_cpu(arc_clockevent_device, cpu); + + clockevents_calc_mult_shift(clk, arc_get_core_freq(), 5); + + clk->max_delta_ns = clockevent_delta2ns(ARC_TIMER_MAX, clk); + clk->cpumask = cpumask_of(cpu); + + clockevents_register_device(clk); + + /* + * setup the per-cpu timer IRQ handler - for all cpus + * For non boot CPU explicitly unmask at intc + * setup_irq() -> .. -> irq_startup() already does this on boot-cpu + */ + if (!cpu) + setup_irq(TIMER0_IRQ, &arc_timer_irq); + else + arch_unmask_irq(TIMER0_IRQ); +} + +/* + * Called from start_kernel() - boot CPU only + * + * -Sets up h/w timers as applicable on boot cpu + * -Also sets up any global state needed for timer subsystem: + * - for "counting" timer, registers a clocksource, usable across CPUs + * (provided that underlying counter h/w is synchronized across cores) + * - for "event" timer, sets up TIMER0 IRQ (as that is platform agnostic) + */ +void __init time_init(void) +{ + /* + * sets up the timekeeping free-flowing counter which also returns + * whether the counter is usable as clocksource + */ + if (arc_counter_setup()) + /* + * CLK upto 4.29 GHz can be safely represented in 32 bits + * because Max 32 bit number is 4,294,967,295 + */ + clocksource_register_hz(&arc_counter, arc_get_core_freq()); + + /* sets up the periodic event timer */ + arc_local_timer_setup(smp_processor_id()); + + if (machine_desc->init_time) + machine_desc->init_time(); +} diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c new file mode 100644 index 00000000000..7496995371e --- /dev/null +++ b/arch/arc/kernel/traps.c @@ -0,0 +1,170 @@ +/* + * Traps/Non-MMU Exception handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: May 2011 + * -user-space unaligned access emulation + * + * Rahul Trivedi: Codito Technologies 2004 + */ + +#include <linux/sched.h> +#include <linux/kdebug.h> +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/setup.h> +#include <asm/kprobes.h> +#include <asm/unaligned.h> +#include <asm/kgdb.h> + +void __init trap_init(void) +{ + return; +} + +void die(const char *str, struct pt_regs *regs, unsigned long address, + unsigned long cause_reg) +{ + show_kernel_fault_diag(str, regs, address, cause_reg); + + /* DEAD END */ + __asm__("flag 1"); +} + +/* + * Helper called for bulk of exceptions NOT needing specific handling + * -for user faults enqueues requested signal + * -for kernel, chk if due to copy_(to|from)_user, otherwise die() + */ +static noinline int handle_exception(unsigned long cause, char *str, + struct pt_regs *regs, siginfo_t *info) +{ + if (user_mode(regs)) { + struct task_struct *tsk = current; + + tsk->thread.fault_address = (__force unsigned int)info->si_addr; + tsk->thread.cause_code = cause; + + force_sig_info(info->si_signo, info, tsk); + + } else { + /* If not due to copy_(to|from)_user, we are doomed */ + if (fixup_exception(regs)) + return 0; + + die(str, regs, (unsigned long)info->si_addr, cause); + } + + return 1; +} + +#define DO_ERROR_INFO(signr, str, name, sicode) \ +int name(unsigned long cause, unsigned long address, struct pt_regs *regs) \ +{ \ + siginfo_t info = { \ + .si_signo = signr, \ + .si_errno = 0, \ + .si_code = sicode, \ + .si_addr = (void __user *)address, \ + }; \ + return handle_exception(cause, str, regs, &info);\ +} + +/* + * Entry points for exceptions NOT needing specific handling + */ +DO_ERROR_INFO(SIGILL, "Priv Op/Disabled Extn", do_privilege_fault, ILL_PRVOPC) +DO_ERROR_INFO(SIGILL, "Invalid Extn Insn", do_extension_fault, ILL_ILLOPC) +DO_ERROR_INFO(SIGILL, "Illegal Insn (or Seq)", insterror_is_error, ILL_ILLOPC) +DO_ERROR_INFO(SIGBUS, "Invalid Mem Access", do_memory_error, BUS_ADRERR) +DO_ERROR_INFO(SIGTRAP, "Breakpoint Set", trap_is_brkpt, TRAP_BRKPT) + +#ifdef CONFIG_ARC_MISALIGN_ACCESS +/* + * Entry Point for Misaligned Data access Exception, for emulating in software + */ +int do_misaligned_access(unsigned long cause, unsigned long address, + struct pt_regs *regs, struct callee_regs *cregs) +{ + if (misaligned_fixup(address, regs, cause, cregs) != 0) { + siginfo_t info; + + info.si_signo = SIGBUS; + info.si_errno = 0; + info.si_code = BUS_ADRALN; + info.si_addr = (void __user *)address; + return handle_exception(cause, "Misaligned Access", regs, + &info); + } + return 0; +} + +#else +DO_ERROR_INFO(SIGSEGV, "Misaligned Access", do_misaligned_access, SEGV_ACCERR) +#endif + +/* + * Entry point for miscll errors such as Nested Exceptions + * -Duplicate TLB entry is handled seperately though + */ +void do_machine_check_fault(unsigned long cause, unsigned long address, + struct pt_regs *regs) +{ + die("Machine Check Exception", regs, address, cause); +} + + +/* + * Entry point for traps induced by ARCompact TRAP_S <n> insn + * This is same family as TRAP0/SWI insn (use the same vector). + * The only difference being SWI insn take no operand, while TRAP_S does + * which reflects in ECR Reg as 8 bit param. + * Thus TRAP_S <n> can be used for specific purpose + * -1 used for software breakpointing (gdb) + * -2 used by kprobes + */ +void do_non_swi_trap(unsigned long cause, unsigned long address, + struct pt_regs *regs) +{ + unsigned int param = cause & 0xff; + + switch (param) { + case 1: + trap_is_brkpt(cause, address, regs); + break; + + case 2: + trap_is_kprobe(param, address, regs); + break; + + case 3: + case 4: + kgdb_trap(regs, param); + break; + + default: + break; + } +} + +/* + * Entry point for Instruction Error Exception + * -For a corner case, ARC kprobes implementation resorts to using + * this exception, hence the check + */ +void do_insterror_or_kprobe(unsigned long cause, + unsigned long address, + struct pt_regs *regs) +{ + /* Check if this exception is caused by kprobes */ + if (notify_die(DIE_IERR, "kprobe_ierr", regs, address, + cause, SIGILL) == NOTIFY_STOP) + return; + + insterror_is_error(cause, address, regs); +} diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c new file mode 100644 index 00000000000..7c10873c311 --- /dev/null +++ b/arch/arc/kernel/troubleshoot.c @@ -0,0 +1,322 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + */ + +#include <linux/ptrace.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/fs.h> +#include <linux/kdev_t.h> +#include <linux/fs_struct.h> +#include <linux/proc_fs.h> +#include <linux/file.h> +#include <asm/arcregs.h> + +/* + * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25) + * -Prints 3 regs per line and a CR. + * -To continue, callee regs right after scratch, special handling of CR + */ +static noinline void print_reg_file(long *reg_rev, int start_num) +{ + unsigned int i; + char buf[512]; + int n = 0, len = sizeof(buf); + + /* weird loop because pt_regs regs rev r12..r0, r25..r13 */ + for (i = start_num; i < start_num + 13; i++) { + n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t", + i, (unsigned long)*reg_rev); + + if (((i + 1) % 3) == 0) + n += scnprintf(buf + n, len - n, "\n"); + + reg_rev--; + } + + if (start_num != 0) + n += scnprintf(buf + n, len - n, "\n\n"); + + pr_info("%s", buf); +} + +static void show_callee_regs(struct callee_regs *cregs) +{ + print_reg_file(&(cregs->r13), 13); +} + +void print_task_path_n_nm(struct task_struct *tsk, char *buf) +{ + struct path path; + char *path_nm = NULL; + struct mm_struct *mm; + struct file *exe_file; + + mm = get_task_mm(tsk); + if (!mm) + goto done; + + exe_file = get_mm_exe_file(mm); + mmput(mm); + + if (exe_file) { + path = exe_file->f_path; + path_get(&exe_file->f_path); + fput(exe_file); + path_nm = d_path(&path, buf, 255); + path_put(&path); + } + +done: + pr_info("%s, TGID %u\n", path_nm, tsk->tgid); +} +EXPORT_SYMBOL(print_task_path_n_nm); + +static void show_faulting_vma(unsigned long address, char *buf) +{ + struct vm_area_struct *vma; + struct inode *inode; + unsigned long ino = 0; + dev_t dev = 0; + char *nm = buf; + + vma = find_vma(current->active_mm, address); + + /* check against the find_vma( ) behaviour which returns the next VMA + * if the container VMA is not found + */ + if (vma && (vma->vm_start <= address)) { + struct file *file = vma->vm_file; + if (file) { + struct path *path = &file->f_path; + nm = d_path(path, buf, PAGE_SIZE - 1); + inode = vma->vm_file->f_path.dentry->d_inode; + dev = inode->i_sb->s_dev; + ino = inode->i_ino; + } + pr_info(" @off 0x%lx in [%s]\n" + " VMA: 0x%08lx to 0x%08lx\n\n", + address - vma->vm_start, nm, vma->vm_start, vma->vm_end); + } else + pr_info(" @No matching VMA found\n"); +} + +static void show_ecr_verbose(struct pt_regs *regs) +{ + unsigned int vec, cause_code, cause_reg; + unsigned long address; + + cause_reg = current->thread.cause_code; + pr_info("\n[ECR]: 0x%08x => ", cause_reg); + + /* For Data fault, this is data address not instruction addr */ + address = current->thread.fault_address; + + vec = cause_reg >> 16; + cause_code = (cause_reg >> 8) & 0xFF; + + /* For DTLB Miss or ProtV, display the memory involved too */ + if (vec == ECR_V_DTLB_MISS) { + pr_cont("Invalid (%s) @ 0x%08lx by insn @ 0x%08lx\n", + (cause_code == 0x01) ? "Read From" : + ((cause_code == 0x02) ? "Write to" : "EX"), + address, regs->ret); + } else if (vec == ECR_V_ITLB_MISS) { + pr_cont("Insn could not be fetched\n"); + } else if (vec == ECR_V_MACH_CHK) { + pr_cont("%s\n", (cause_code == 0x0) ? + "Double Fault" : "Other Fatal Err"); + + } else if (vec == ECR_V_PROTV) { + if (cause_code == ECR_C_PROTV_INST_FETCH) + pr_cont("Execute from Non-exec Page\n"); + else if (cause_code == ECR_C_PROTV_LOAD) + pr_cont("Read from Non-readable Page\n"); + else if (cause_code == ECR_C_PROTV_STORE) + pr_cont("Write to Non-writable Page\n"); + else if (cause_code == ECR_C_PROTV_XCHG) + pr_cont("Data exchange protection violation\n"); + else if (cause_code == ECR_C_PROTV_MISALIG_DATA) + pr_cont("Misaligned r/w from 0x%08lx\n", address); + } else if (vec == ECR_V_INSN_ERR) { + pr_cont("Illegal Insn\n"); + } else { + pr_cont("Check Programmer's Manual\n"); + } +} + +/************************************************************************ + * API called by rest of kernel + ***********************************************************************/ + +void show_regs(struct pt_regs *regs) +{ + struct task_struct *tsk = current; + struct callee_regs *cregs; + char *buf; + + buf = (char *)__get_free_page(GFP_TEMPORARY); + if (!buf) + return; + + print_task_path_n_nm(tsk, buf); + + if (current->thread.cause_code) + show_ecr_verbose(regs); + + pr_info("[EFA]: 0x%08lx\n", current->thread.fault_address); + pr_info("[ERET]: 0x%08lx (PC of Faulting Instr)\n", regs->ret); + + show_faulting_vma(regs->ret, buf); /* faulting code, not data */ + + /* can't use print_vma_addr() yet as it doesn't check for + * non-inclusive vma + */ + + /* print special regs */ + pr_info("status32: 0x%08lx\n", regs->status32); + pr_info(" SP: 0x%08lx\tFP: 0x%08lx\n", regs->sp, regs->fp); + pr_info("BTA: 0x%08lx\tBLINK: 0x%08lx\n", + regs->bta, regs->blink); + pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n", + regs->lp_start, regs->lp_end, regs->lp_count); + + /* print regs->r0 thru regs->r12 + * Sequential printing was generating horrible code + */ + print_reg_file(&(regs->r0), 0); + + /* If Callee regs were saved, display them too */ + cregs = (struct callee_regs *)current->thread.callee_reg; + if (cregs) + show_callee_regs(cregs); + + free_page((unsigned long)buf); +} + +void show_kernel_fault_diag(const char *str, struct pt_regs *regs, + unsigned long address, unsigned long cause_reg) +{ + current->thread.fault_address = address; + current->thread.cause_code = cause_reg; + + /* Caller and Callee regs */ + show_regs(regs); + + /* Show stack trace if this Fatality happened in kernel mode */ + if (!user_mode(regs)) + show_stacktrace(current, regs); +} + +#ifdef CONFIG_DEBUG_FS + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/mount.h> +#include <linux/pagemap.h> +#include <linux/init.h> +#include <linux/namei.h> +#include <linux/debugfs.h> + +static struct dentry *test_dentry; +static struct dentry *test_dir; +static struct dentry *test_u32_dentry; + +static u32 clr_on_read = 1; + +#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT +u32 numitlb, numdtlb, num_pte_not_present; + +static int fill_display_data(char *kbuf) +{ + size_t num = 0; + num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb); + num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb); + num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present); + + if (clr_on_read) + numitlb = numdtlb = num_pte_not_present = 0; + + return num; +} + +static int tlb_stats_open(struct inode *inode, struct file *file) +{ + file->private_data = (void *)__get_free_page(GFP_KERNEL); + return 0; +} + +/* called on user read(): display the couters */ +static ssize_t tlb_stats_output(struct file *file, /* file descriptor */ + char __user *user_buf, /* user buffer */ + size_t len, /* length of buffer */ + loff_t *offset) /* offset in the file */ +{ + size_t num; + char *kbuf = (char *)file->private_data; + + /* All of the data can he shoved in one iteration */ + if (*offset != 0) + return 0; + + num = fill_display_data(kbuf); + + /* simple_read_from_buffer() is helper for copy to user space + It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset + @3 (offset) into the user space address starting at @1 (user_buf). + @5 (len) is max size of user buffer + */ + return simple_read_from_buffer(user_buf, num, offset, kbuf, len); +} + +/* called on user write : clears the counters */ +static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf, + size_t length, loff_t *offset) +{ + numitlb = numdtlb = num_pte_not_present = 0; + return length; +} + +static int tlb_stats_close(struct inode *inode, struct file *file) +{ + free_page((unsigned long)(file->private_data)); + return 0; +} + +static const struct file_operations tlb_stats_file_ops = { + .read = tlb_stats_output, + .write = tlb_stats_clear, + .open = tlb_stats_open, + .release = tlb_stats_close +}; +#endif + +static int __init arc_debugfs_init(void) +{ + test_dir = debugfs_create_dir("arc", NULL); + +#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT + test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL, + &tlb_stats_file_ops); +#endif + + test_u32_dentry = + debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read); + + return 0; +} + +module_init(arc_debugfs_init); + +static void __exit arc_debugfs_exit(void) +{ + debugfs_remove(test_u32_dentry); + debugfs_remove(test_dentry); + debugfs_remove(test_dir); +} +module_exit(arc_debugfs_exit); + +#endif diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c new file mode 100644 index 00000000000..4cd81633feb --- /dev/null +++ b/arch/arc/kernel/unaligned.c @@ -0,0 +1,245 @@ +/* + * Copyright (C) 2011-2012 Synopsys (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg : May 2011 + * -Adapted (from .26 to .35) + * -original contribution by Tim.yao@amlogic.com + * + */ + +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/uaccess.h> +#include <asm/disasm.h> + +#define __get8_unaligned_check(val, addr, err) \ + __asm__( \ + "1: ldb.ab %1, [%2, 1]\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "3: mov %0, 1\n" \ + " b 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 3b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (val), "=r" (addr) \ + : "0" (err), "2" (addr)) + +#define get16_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v, a = addr; \ + __get8_unaligned_check(v, a, err); \ + val = v ; \ + __get8_unaligned_check(v, a, err); \ + val |= v << 8; \ + if (err) \ + goto fault; \ + } while (0) + +#define get32_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v, a = addr; \ + __get8_unaligned_check(v, a, err); \ + val = v << 0; \ + __get8_unaligned_check(v, a, err); \ + val |= v << 8; \ + __get8_unaligned_check(v, a, err); \ + val |= v << 16; \ + __get8_unaligned_check(v, a, err); \ + val |= v << 24; \ + if (err) \ + goto fault; \ + } while (0) + +#define put16_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v = val, a = addr;\ + \ + __asm__( \ + "1: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "2: stb %1, [%2]\n" \ + "3:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "4: mov %0, 1\n" \ + " b 3b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 4b\n" \ + " .long 2b, 4b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (v), "=&r" (a) \ + : "0" (err), "1" (v), "2" (a)); \ + \ + if (err) \ + goto fault; \ + } while (0) + +#define put32_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v = val, a = addr;\ + __asm__( \ + \ + "1: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "2: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "3: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "4: stb %1, [%2]\n" \ + "5:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "6: mov %0, 1\n" \ + " b 5b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 6b\n" \ + " .long 2b, 6b\n" \ + " .long 3b, 6b\n" \ + " .long 4b, 6b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (v), "=&r" (a) \ + : "0" (err), "1" (v), "2" (a)); \ + \ + if (err) \ + goto fault; \ + } while (0) + +/* sysctl hooks */ +int unaligned_enabled __read_mostly = 1; /* Enabled by default */ +int no_unaligned_warning __read_mostly = 1; /* Only 1 warning by default */ + +static void fixup_load(struct disasm_state *state, struct pt_regs *regs, + struct callee_regs *cregs) +{ + int val; + + /* register write back */ + if ((state->aa == 1) || (state->aa == 2)) { + set_reg(state->wb_reg, state->src1 + state->src2, regs, cregs); + + if (state->aa == 2) + state->src2 = 0; + } + + if (state->zz == 0) { + get32_unaligned_check(val, state->src1 + state->src2); + } else { + get16_unaligned_check(val, state->src1 + state->src2); + + if (state->x) + val = (val << 16) >> 16; + } + + if (state->pref == 0) + set_reg(state->dest, val, regs, cregs); + + return; + +fault: state->fault = 1; +} + +static void fixup_store(struct disasm_state *state, struct pt_regs *regs, + struct callee_regs *cregs) +{ + /* register write back */ + if ((state->aa == 1) || (state->aa == 2)) { + set_reg(state->wb_reg, state->src2 + state->src3, regs, cregs); + + if (state->aa == 3) + state->src3 = 0; + } else if (state->aa == 3) { + if (state->zz == 2) { + set_reg(state->wb_reg, state->src2 + (state->src3 << 1), + regs, cregs); + } else if (!state->zz) { + set_reg(state->wb_reg, state->src2 + (state->src3 << 2), + regs, cregs); + } else { + goto fault; + } + } + + /* write fix-up */ + if (!state->zz) + put32_unaligned_check(state->src1, state->src2 + state->src3); + else + put16_unaligned_check(state->src1, state->src2 + state->src3); + + return; + +fault: state->fault = 1; +} + +/* + * Handle an unaligned access + * Returns 0 if successfully handled, 1 if some error happened + */ +int misaligned_fixup(unsigned long address, struct pt_regs *regs, + unsigned long cause, struct callee_regs *cregs) +{ + struct disasm_state state; + char buf[TASK_COMM_LEN]; + + /* handle user mode only and only if enabled by sysadmin */ + if (!user_mode(regs) || !unaligned_enabled) + return 1; + + if (no_unaligned_warning) { + pr_warn_once("%s(%d) made unaligned access which was emulated" + " by kernel assist\n. This can degrade application" + " performance significantly\n. To enable further" + " logging of such instances, please \n" + " echo 0 > /proc/sys/kernel/ignore-unaligned-usertrap\n", + get_task_comm(buf, current), task_pid_nr(current)); + } else { + /* Add rate limiting if it gets down to it */ + pr_warn("%s(%d): unaligned access to/from 0x%lx by PC: 0x%lx\n", + get_task_comm(buf, current), task_pid_nr(current), + address, regs->ret); + + } + + disasm_instr(regs->ret, &state, 1, regs, cregs); + + if (state.fault) + goto fault; + + /* ldb/stb should not have unaligned exception */ + if ((state.zz == 1) || (state.di)) + goto fault; + + if (!state.write) + fixup_load(&state, regs, cregs); + else + fixup_store(&state, regs, cregs); + + if (state.fault) + goto fault; + + if (delay_mode(regs)) { + regs->ret = regs->bta; + regs->status32 &= ~STATUS_DE_MASK; + } else { + regs->ret += state.instr_len; + } + + return 0; + +fault: + pr_err("Alignment trap: fault in fix-up %08lx at [<%08lx>]\n", + state.words[0], address); + + return 1; +} diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c new file mode 100644 index 00000000000..a8d02223da4 --- /dev/null +++ b/arch/arc/kernel/unwind.c @@ -0,0 +1,1329 @@ +/* + * Copyright (C) 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2002-2006 Novell, Inc. + * Jan Beulich <jbeulich@novell.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * A simple API for unwinding kernel stacks. This is used for + * debugging and error reporting purposes. The kernel doesn't need + * full-blown stack unwinding with all the bells and whistles, so there + * is not much point in implementing the full Dwarf2 unwind API. + */ + +#include <linux/sched.h> +#include <linux/module.h> +#include <linux/bootmem.h> +#include <linux/sort.h> +#include <linux/slab.h> +#include <linux/stop_machine.h> +#include <linux/uaccess.h> +#include <linux/ptrace.h> +#include <asm/sections.h> +#include <asm/unaligned.h> +#include <asm/unwind.h> + +extern char __start_unwind[], __end_unwind[]; +/* extern const u8 __start_unwind_hdr[], __end_unwind_hdr[];*/ + +/* #define UNWIND_DEBUG */ + +#ifdef UNWIND_DEBUG +int dbg_unw; +#define unw_debug(fmt, ...) \ +do { \ + if (dbg_unw) \ + pr_info(fmt, ##__VA_ARGS__); \ +} while (0); +#else +#define unw_debug(fmt, ...) +#endif + +#define MAX_STACK_DEPTH 8 + +#define EXTRA_INFO(f) { \ + BUILD_BUG_ON_ZERO(offsetof(struct unwind_frame_info, f) \ + % FIELD_SIZEOF(struct unwind_frame_info, f)) \ + + offsetof(struct unwind_frame_info, f) \ + / FIELD_SIZEOF(struct unwind_frame_info, f), \ + FIELD_SIZEOF(struct unwind_frame_info, f) \ + } +#define PTREGS_INFO(f) EXTRA_INFO(regs.f) + +static const struct { + unsigned offs:BITS_PER_LONG / 2; + unsigned width:BITS_PER_LONG / 2; +} reg_info[] = { +UNW_REGISTER_INFO}; + +#undef PTREGS_INFO +#undef EXTRA_INFO + +#ifndef REG_INVALID +#define REG_INVALID(r) (reg_info[r].width == 0) +#endif + +#define DW_CFA_nop 0x00 +#define DW_CFA_set_loc 0x01 +#define DW_CFA_advance_loc1 0x02 +#define DW_CFA_advance_loc2 0x03 +#define DW_CFA_advance_loc4 0x04 +#define DW_CFA_offset_extended 0x05 +#define DW_CFA_restore_extended 0x06 +#define DW_CFA_undefined 0x07 +#define DW_CFA_same_value 0x08 +#define DW_CFA_register 0x09 +#define DW_CFA_remember_state 0x0a +#define DW_CFA_restore_state 0x0b +#define DW_CFA_def_cfa 0x0c +#define DW_CFA_def_cfa_register 0x0d +#define DW_CFA_def_cfa_offset 0x0e +#define DW_CFA_def_cfa_expression 0x0f +#define DW_CFA_expression 0x10 +#define DW_CFA_offset_extended_sf 0x11 +#define DW_CFA_def_cfa_sf 0x12 +#define DW_CFA_def_cfa_offset_sf 0x13 +#define DW_CFA_val_offset 0x14 +#define DW_CFA_val_offset_sf 0x15 +#define DW_CFA_val_expression 0x16 +#define DW_CFA_lo_user 0x1c +#define DW_CFA_GNU_window_save 0x2d +#define DW_CFA_GNU_args_size 0x2e +#define DW_CFA_GNU_negative_offset_extended 0x2f +#define DW_CFA_hi_user 0x3f + +#define DW_EH_PE_FORM 0x07 +#define DW_EH_PE_native 0x00 +#define DW_EH_PE_leb128 0x01 +#define DW_EH_PE_data2 0x02 +#define DW_EH_PE_data4 0x03 +#define DW_EH_PE_data8 0x04 +#define DW_EH_PE_signed 0x08 +#define DW_EH_PE_ADJUST 0x70 +#define DW_EH_PE_abs 0x00 +#define DW_EH_PE_pcrel 0x10 +#define DW_EH_PE_textrel 0x20 +#define DW_EH_PE_datarel 0x30 +#define DW_EH_PE_funcrel 0x40 +#define DW_EH_PE_aligned 0x50 +#define DW_EH_PE_indirect 0x80 +#define DW_EH_PE_omit 0xff + +typedef unsigned long uleb128_t; +typedef signed long sleb128_t; + +static struct unwind_table { + struct { + unsigned long pc; + unsigned long range; + } core, init; + const void *address; + unsigned long size; + const unsigned char *header; + unsigned long hdrsz; + struct unwind_table *link; + const char *name; +} root_table; + +struct unwind_item { + enum item_location { + Nowhere, + Memory, + Register, + Value + } where; + uleb128_t value; +}; + +struct unwind_state { + uleb128_t loc, org; + const u8 *cieStart, *cieEnd; + uleb128_t codeAlign; + sleb128_t dataAlign; + struct cfa { + uleb128_t reg, offs; + } cfa; + struct unwind_item regs[ARRAY_SIZE(reg_info)]; + unsigned stackDepth:8; + unsigned version:8; + const u8 *label; + const u8 *stack[MAX_STACK_DEPTH]; +}; + +static const struct cfa badCFA = { ARRAY_SIZE(reg_info), 1 }; + +static struct unwind_table *find_table(unsigned long pc) +{ + struct unwind_table *table; + + for (table = &root_table; table; table = table->link) + if ((pc >= table->core.pc + && pc < table->core.pc + table->core.range) + || (pc >= table->init.pc + && pc < table->init.pc + table->init.range)) + break; + + return table; +} + +static unsigned long read_pointer(const u8 **pLoc, + const void *end, signed ptrType); + +static void init_unwind_table(struct unwind_table *table, const char *name, + const void *core_start, unsigned long core_size, + const void *init_start, unsigned long init_size, + const void *table_start, unsigned long table_size, + const u8 *header_start, unsigned long header_size) +{ + const u8 *ptr = header_start + 4; + const u8 *end = header_start + header_size; + + table->core.pc = (unsigned long)core_start; + table->core.range = core_size; + table->init.pc = (unsigned long)init_start; + table->init.range = init_size; + table->address = table_start; + table->size = table_size; + + /* See if the linker provided table looks valid. */ + if (header_size <= 4 + || header_start[0] != 1 + || (void *)read_pointer(&ptr, end, header_start[1]) != table_start + || header_start[2] == DW_EH_PE_omit + || read_pointer(&ptr, end, header_start[2]) <= 0 + || header_start[3] == DW_EH_PE_omit) + header_start = NULL; + + table->hdrsz = header_size; + smp_wmb(); + table->header = header_start; + table->link = NULL; + table->name = name; +} + +void __init arc_unwind_init(void) +{ + init_unwind_table(&root_table, "kernel", _text, _end - _text, NULL, 0, + __start_unwind, __end_unwind - __start_unwind, + NULL, 0); + /*__start_unwind_hdr, __end_unwind_hdr - __start_unwind_hdr);*/ +} + +static const u32 bad_cie, not_fde; +static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *); +static signed fde_pointer_type(const u32 *cie); + +struct eh_frame_hdr_table_entry { + unsigned long start, fde; +}; + +static int cmp_eh_frame_hdr_table_entries(const void *p1, const void *p2) +{ + const struct eh_frame_hdr_table_entry *e1 = p1; + const struct eh_frame_hdr_table_entry *e2 = p2; + + return (e1->start > e2->start) - (e1->start < e2->start); +} + +static void swap_eh_frame_hdr_table_entries(void *p1, void *p2, int size) +{ + struct eh_frame_hdr_table_entry *e1 = p1; + struct eh_frame_hdr_table_entry *e2 = p2; + unsigned long v; + + v = e1->start; + e1->start = e2->start; + e2->start = v; + v = e1->fde; + e1->fde = e2->fde; + e2->fde = v; +} + +static void __init setup_unwind_table(struct unwind_table *table, + void *(*alloc) (unsigned long)) +{ + const u8 *ptr; + unsigned long tableSize = table->size, hdrSize; + unsigned n; + const u32 *fde; + struct { + u8 version; + u8 eh_frame_ptr_enc; + u8 fde_count_enc; + u8 table_enc; + unsigned long eh_frame_ptr; + unsigned int fde_count; + struct eh_frame_hdr_table_entry table[]; + } __attribute__ ((__packed__)) *header; + + if (table->header) + return; + + if (table->hdrsz) + pr_warn(".eh_frame_hdr for '%s' present but unusable\n", + table->name); + + if (tableSize & (sizeof(*fde) - 1)) + return; + + for (fde = table->address, n = 0; + tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde; + tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { + const u32 *cie = cie_for_fde(fde, table); + signed ptrType; + + if (cie == ¬_fde) + continue; + if (cie == NULL || cie == &bad_cie) + return; + ptrType = fde_pointer_type(cie); + if (ptrType < 0) + return; + + ptr = (const u8 *)(fde + 2); + if (!read_pointer(&ptr, (const u8 *)(fde + 1) + *fde, + ptrType)) { + /* FIXME_Rajesh We have 4 instances of null addresses + * instead of the initial loc addr + * return; + */ + } + ++n; + } + + if (tableSize || !n) + return; + + hdrSize = 4 + sizeof(unsigned long) + sizeof(unsigned int) + + 2 * n * sizeof(unsigned long); + header = alloc(hdrSize); + if (!header) + return; + header->version = 1; + header->eh_frame_ptr_enc = DW_EH_PE_abs | DW_EH_PE_native; + header->fde_count_enc = DW_EH_PE_abs | DW_EH_PE_data4; + header->table_enc = DW_EH_PE_abs | DW_EH_PE_native; + put_unaligned((unsigned long)table->address, &header->eh_frame_ptr); + BUILD_BUG_ON(offsetof(typeof(*header), fde_count) + % __alignof(typeof(header->fde_count))); + header->fde_count = n; + + BUILD_BUG_ON(offsetof(typeof(*header), table) + % __alignof(typeof(*header->table))); + for (fde = table->address, tableSize = table->size, n = 0; + tableSize; + tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { + /* const u32 *cie = fde + 1 - fde[1] / sizeof(*fde); */ + const u32 *cie = (const u32 *)(fde[1]); + + if (fde[1] == 0xffffffff) + continue; /* this is a CIE */ + ptr = (const u8 *)(fde + 2); + header->table[n].start = read_pointer(&ptr, + (const u8 *)(fde + 1) + + *fde, + fde_pointer_type(cie)); + header->table[n].fde = (unsigned long)fde; + ++n; + } + WARN_ON(n != header->fde_count); + + sort(header->table, + n, + sizeof(*header->table), + cmp_eh_frame_hdr_table_entries, swap_eh_frame_hdr_table_entries); + + table->hdrsz = hdrSize; + smp_wmb(); + table->header = (const void *)header; +} + +static void *__init balloc(unsigned long sz) +{ + return __alloc_bootmem_nopanic(sz, + sizeof(unsigned int), + __pa(MAX_DMA_ADDRESS)); +} + +void __init arc_unwind_setup(void) +{ + setup_unwind_table(&root_table, balloc); +} + +#ifdef CONFIG_MODULES + +static struct unwind_table *last_table; + +/* Must be called with module_mutex held. */ +void *unwind_add_table(struct module *module, const void *table_start, + unsigned long table_size) +{ + struct unwind_table *table; + + if (table_size <= 0) + return NULL; + + table = kmalloc(sizeof(*table), GFP_KERNEL); + if (!table) + return NULL; + + init_unwind_table(table, module->name, + module->module_core, module->core_size, + module->module_init, module->init_size, + table_start, table_size, + NULL, 0); + +#ifdef UNWIND_DEBUG + unw_debug("Table added for [%s] %lx %lx\n", + module->name, table->core.pc, table->core.range); +#endif + if (last_table) + last_table->link = table; + else + root_table.link = table; + last_table = table; + + return table; +} + +struct unlink_table_info { + struct unwind_table *table; + int init_only; +}; + +static int unlink_table(void *arg) +{ + struct unlink_table_info *info = arg; + struct unwind_table *table = info->table, *prev; + + for (prev = &root_table; prev->link && prev->link != table; + prev = prev->link) + ; + + if (prev->link) { + if (info->init_only) { + table->init.pc = 0; + table->init.range = 0; + info->table = NULL; + } else { + prev->link = table->link; + if (!prev->link) + last_table = prev; + } + } else + info->table = NULL; + + return 0; +} + +/* Must be called with module_mutex held. */ +void unwind_remove_table(void *handle, int init_only) +{ + struct unwind_table *table = handle; + struct unlink_table_info info; + + if (!table || table == &root_table) + return; + + if (init_only && table == last_table) { + table->init.pc = 0; + table->init.range = 0; + return; + } + + info.table = table; + info.init_only = init_only; + + unlink_table(&info); /* XXX: SMP */ + kfree(table); +} + +#endif /* CONFIG_MODULES */ + +static uleb128_t get_uleb128(const u8 **pcur, const u8 *end) +{ + const u8 *cur = *pcur; + uleb128_t value; + unsigned shift; + + for (shift = 0, value = 0; cur < end; shift += 7) { + if (shift + 7 > 8 * sizeof(value) + && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { + cur = end + 1; + break; + } + value |= (uleb128_t) (*cur & 0x7f) << shift; + if (!(*cur++ & 0x80)) + break; + } + *pcur = cur; + + return value; +} + +static sleb128_t get_sleb128(const u8 **pcur, const u8 *end) +{ + const u8 *cur = *pcur; + sleb128_t value; + unsigned shift; + + for (shift = 0, value = 0; cur < end; shift += 7) { + if (shift + 7 > 8 * sizeof(value) + && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { + cur = end + 1; + break; + } + value |= (sleb128_t) (*cur & 0x7f) << shift; + if (!(*cur & 0x80)) { + value |= -(*cur++ & 0x40) << shift; + break; + } + } + *pcur = cur; + + return value; +} + +static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table) +{ + const u32 *cie; + + if (!*fde || (*fde & (sizeof(*fde) - 1))) + return &bad_cie; + + if (fde[1] == 0xffffffff) + return ¬_fde; /* this is a CIE */ + + if ((fde[1] & (sizeof(*fde) - 1))) +/* || fde[1] > (unsigned long)(fde + 1) - (unsigned long)table->address) */ + return NULL; /* this is not a valid FDE */ + + /* cie = fde + 1 - fde[1] / sizeof(*fde); */ + cie = (u32 *) fde[1]; + + if (*cie <= sizeof(*cie) + 4 || *cie >= fde[1] - sizeof(*fde) + || (*cie & (sizeof(*cie) - 1)) + || (cie[1] != 0xffffffff)) + return NULL; /* this is not a (valid) CIE */ + return cie; +} + +static unsigned long read_pointer(const u8 **pLoc, const void *end, + signed ptrType) +{ + unsigned long value = 0; + union { + const u8 *p8; + const u16 *p16u; + const s16 *p16s; + const u32 *p32u; + const s32 *p32s; + const unsigned long *pul; + } ptr; + + if (ptrType < 0 || ptrType == DW_EH_PE_omit) + return 0; + ptr.p8 = *pLoc; + switch (ptrType & DW_EH_PE_FORM) { + case DW_EH_PE_data2: + if (end < (const void *)(ptr.p16u + 1)) + return 0; + if (ptrType & DW_EH_PE_signed) + value = get_unaligned((u16 *) ptr.p16s++); + else + value = get_unaligned((u16 *) ptr.p16u++); + break; + case DW_EH_PE_data4: +#ifdef CONFIG_64BIT + if (end < (const void *)(ptr.p32u + 1)) + return 0; + if (ptrType & DW_EH_PE_signed) + value = get_unaligned(ptr.p32s++); + else + value = get_unaligned(ptr.p32u++); + break; + case DW_EH_PE_data8: + BUILD_BUG_ON(sizeof(u64) != sizeof(value)); +#else + BUILD_BUG_ON(sizeof(u32) != sizeof(value)); +#endif + case DW_EH_PE_native: + if (end < (const void *)(ptr.pul + 1)) + return 0; + value = get_unaligned((unsigned long *)ptr.pul++); + break; + case DW_EH_PE_leb128: + BUILD_BUG_ON(sizeof(uleb128_t) > sizeof(value)); + value = ptrType & DW_EH_PE_signed ? get_sleb128(&ptr.p8, end) + : get_uleb128(&ptr.p8, end); + if ((const void *)ptr.p8 > end) + return 0; + break; + default: + return 0; + } + switch (ptrType & DW_EH_PE_ADJUST) { + case DW_EH_PE_abs: + break; + case DW_EH_PE_pcrel: + value += (unsigned long)*pLoc; + break; + default: + return 0; + } + if ((ptrType & DW_EH_PE_indirect) + && __get_user(value, (unsigned long __user *)value)) + return 0; + *pLoc = ptr.p8; + + return value; +} + +static signed fde_pointer_type(const u32 *cie) +{ + const u8 *ptr = (const u8 *)(cie + 2); + unsigned version = *ptr; + + if (version != 1) + return -1; /* unsupported */ + + if (*++ptr) { + const char *aug; + const u8 *end = (const u8 *)(cie + 1) + *cie; + uleb128_t len; + + /* check if augmentation size is first (and thus present) */ + if (*ptr != 'z') + return -1; + + /* check if augmentation string is nul-terminated */ + aug = (const void *)ptr; + ptr = memchr(aug, 0, end - ptr); + if (ptr == NULL) + return -1; + + ++ptr; /* skip terminator */ + get_uleb128(&ptr, end); /* skip code alignment */ + get_sleb128(&ptr, end); /* skip data alignment */ + /* skip return address column */ + version <= 1 ? (void) ++ptr : (void)get_uleb128(&ptr, end); + len = get_uleb128(&ptr, end); /* augmentation length */ + + if (ptr + len < ptr || ptr + len > end) + return -1; + + end = ptr + len; + while (*++aug) { + if (ptr >= end) + return -1; + switch (*aug) { + case 'L': + ++ptr; + break; + case 'P':{ + signed ptrType = *ptr++; + + if (!read_pointer(&ptr, end, ptrType) + || ptr > end) + return -1; + } + break; + case 'R': + return *ptr; + default: + return -1; + } + } + } + return DW_EH_PE_native | DW_EH_PE_abs; +} + +static int advance_loc(unsigned long delta, struct unwind_state *state) +{ + state->loc += delta * state->codeAlign; + + /* FIXME_Rajesh: Probably we are defining for the initial range as well; + return delta > 0; + */ + unw_debug("delta %3lu => loc 0x%lx: ", delta, state->loc); + return 1; +} + +static void set_rule(uleb128_t reg, enum item_location where, uleb128_t value, + struct unwind_state *state) +{ + if (reg < ARRAY_SIZE(state->regs)) { + state->regs[reg].where = where; + state->regs[reg].value = value; + +#ifdef UNWIND_DEBUG + unw_debug("r%lu: ", reg); + switch (where) { + case Nowhere: + unw_debug("s "); + break; + case Memory: + unw_debug("c(%lu) ", value); + break; + case Register: + unw_debug("r(%lu) ", value); + break; + case Value: + unw_debug("v(%lu) ", value); + break; + default: + break; + } +#endif + } +} + +static int processCFI(const u8 *start, const u8 *end, unsigned long targetLoc, + signed ptrType, struct unwind_state *state) +{ + union { + const u8 *p8; + const u16 *p16; + const u32 *p32; + } ptr; + int result = 1; + u8 opcode; + + if (start != state->cieStart) { + state->loc = state->org; + result = + processCFI(state->cieStart, state->cieEnd, 0, ptrType, + state); + if (targetLoc == 0 && state->label == NULL) + return result; + } + for (ptr.p8 = start; result && ptr.p8 < end;) { + switch (*ptr.p8 >> 6) { + uleb128_t value; + + case 0: + opcode = *ptr.p8++; + + switch (opcode) { + case DW_CFA_nop: + unw_debug("cfa nop "); + break; + case DW_CFA_set_loc: + state->loc = read_pointer(&ptr.p8, end, + ptrType); + if (state->loc == 0) + result = 0; + unw_debug("cfa_set_loc: 0x%lx ", state->loc); + break; + case DW_CFA_advance_loc1: + unw_debug("\ncfa advance loc1:"); + result = ptr.p8 < end + && advance_loc(*ptr.p8++, state); + break; + case DW_CFA_advance_loc2: + value = *ptr.p8++; + value += *ptr.p8++ << 8; + unw_debug("\ncfa advance loc2:"); + result = ptr.p8 <= end + 2 + /* && advance_loc(*ptr.p16++, state); */ + && advance_loc(value, state); + break; + case DW_CFA_advance_loc4: + unw_debug("\ncfa advance loc4:"); + result = ptr.p8 <= end + 4 + && advance_loc(*ptr.p32++, state); + break; + case DW_CFA_offset_extended: + value = get_uleb128(&ptr.p8, end); + unw_debug("cfa_offset_extended: "); + set_rule(value, Memory, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_val_offset: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Value, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_offset_extended_sf: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Memory, + get_sleb128(&ptr.p8, end), state); + break; + case DW_CFA_val_offset_sf: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Value, + get_sleb128(&ptr.p8, end), state); + break; + case DW_CFA_restore_extended: + unw_debug("cfa_restore_extended: "); + case DW_CFA_undefined: + unw_debug("cfa_undefined: "); + case DW_CFA_same_value: + unw_debug("cfa_same_value: "); + set_rule(get_uleb128(&ptr.p8, end), Nowhere, 0, + state); + break; + case DW_CFA_register: + unw_debug("cfa_register: "); + value = get_uleb128(&ptr.p8, end); + set_rule(value, + Register, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_remember_state: + unw_debug("cfa_remember_state: "); + if (ptr.p8 == state->label) { + state->label = NULL; + return 1; + } + if (state->stackDepth >= MAX_STACK_DEPTH) + return 0; + state->stack[state->stackDepth++] = ptr.p8; + break; + case DW_CFA_restore_state: + unw_debug("cfa_restore_state: "); + if (state->stackDepth) { + const uleb128_t loc = state->loc; + const u8 *label = state->label; + + state->label = + state->stack[state->stackDepth - 1]; + memcpy(&state->cfa, &badCFA, + sizeof(state->cfa)); + memset(state->regs, 0, + sizeof(state->regs)); + state->stackDepth = 0; + result = + processCFI(start, end, 0, ptrType, + state); + state->loc = loc; + state->label = label; + } else + return 0; + break; + case DW_CFA_def_cfa: + state->cfa.reg = get_uleb128(&ptr.p8, end); + unw_debug("cfa_def_cfa: r%lu ", state->cfa.reg); + /*nobreak*/ + case DW_CFA_def_cfa_offset: + state->cfa.offs = get_uleb128(&ptr.p8, end); + unw_debug("cfa_def_cfa_offset: 0x%lx ", + state->cfa.offs); + break; + case DW_CFA_def_cfa_sf: + state->cfa.reg = get_uleb128(&ptr.p8, end); + /*nobreak */ + case DW_CFA_def_cfa_offset_sf: + state->cfa.offs = get_sleb128(&ptr.p8, end) + * state->dataAlign; + break; + case DW_CFA_def_cfa_register: + unw_debug("cfa_def_cfa_regsiter: "); + state->cfa.reg = get_uleb128(&ptr.p8, end); + break; + /*todo case DW_CFA_def_cfa_expression: */ + /*todo case DW_CFA_expression: */ + /*todo case DW_CFA_val_expression: */ + case DW_CFA_GNU_args_size: + get_uleb128(&ptr.p8, end); + break; + case DW_CFA_GNU_negative_offset_extended: + value = get_uleb128(&ptr.p8, end); + set_rule(value, + Memory, + (uleb128_t) 0 - get_uleb128(&ptr.p8, + end), + state); + break; + case DW_CFA_GNU_window_save: + default: + unw_debug("UNKNOW OPCODE 0x%x\n", opcode); + result = 0; + break; + } + break; + case 1: + unw_debug("\ncfa_adv_loc: "); + result = advance_loc(*ptr.p8++ & 0x3f, state); + break; + case 2: + unw_debug("cfa_offset: "); + value = *ptr.p8++ & 0x3f; + set_rule(value, Memory, get_uleb128(&ptr.p8, end), + state); + break; + case 3: + unw_debug("cfa_restore: "); + set_rule(*ptr.p8++ & 0x3f, Nowhere, 0, state); + break; + } + + if (ptr.p8 > end) + result = 0; + if (result && targetLoc != 0 && targetLoc < state->loc) + return 1; + } + + return result && ptr.p8 == end && (targetLoc == 0 || ( + /*todo While in theory this should apply, gcc in practice omits + everything past the function prolog, and hence the location + never reaches the end of the function. + targetLoc < state->loc && */ state->label == NULL)); +} + +/* Unwind to previous to frame. Returns 0 if successful, negative + * number in case of an error. */ +int arc_unwind(struct unwind_frame_info *frame) +{ +#define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs]) + const u32 *fde = NULL, *cie = NULL; + const u8 *ptr = NULL, *end = NULL; + unsigned long pc = UNW_PC(frame) - frame->call_frame; + unsigned long startLoc = 0, endLoc = 0, cfa; + unsigned i; + signed ptrType = -1; + uleb128_t retAddrReg = 0; + const struct unwind_table *table; + struct unwind_state state; + unsigned long *fptr; + unsigned long addr; + + unw_debug("\n\nUNWIND FRAME:\n"); + unw_debug("PC: 0x%lx BLINK: 0x%lx, SP: 0x%lx, FP: 0x%x\n", + UNW_PC(frame), UNW_BLINK(frame), UNW_SP(frame), + UNW_FP(frame)); + + if (UNW_PC(frame) == 0) + return -EINVAL; + +#ifdef UNWIND_DEBUG + { + unsigned long *sptr = (unsigned long *)UNW_SP(frame); + unw_debug("\nStack Dump:\n"); + for (i = 0; i < 20; i++, sptr++) + unw_debug("0x%p: 0x%lx\n", sptr, *sptr); + unw_debug("\n"); + } +#endif + + table = find_table(pc); + if (table != NULL + && !(table->size & (sizeof(*fde) - 1))) { + const u8 *hdr = table->header; + unsigned long tableSize; + + smp_rmb(); + if (hdr && hdr[0] == 1) { + switch (hdr[3] & DW_EH_PE_FORM) { + case DW_EH_PE_native: + tableSize = sizeof(unsigned long); + break; + case DW_EH_PE_data2: + tableSize = 2; + break; + case DW_EH_PE_data4: + tableSize = 4; + break; + case DW_EH_PE_data8: + tableSize = 8; + break; + default: + tableSize = 0; + break; + } + ptr = hdr + 4; + end = hdr + table->hdrsz; + if (tableSize && read_pointer(&ptr, end, hdr[1]) + == (unsigned long)table->address + && (i = read_pointer(&ptr, end, hdr[2])) > 0 + && i == (end - ptr) / (2 * tableSize) + && !((end - ptr) % (2 * tableSize))) { + do { + const u8 *cur = + ptr + (i / 2) * (2 * tableSize); + + startLoc = read_pointer(&cur, + cur + tableSize, + hdr[3]); + if (pc < startLoc) + i /= 2; + else { + ptr = cur - tableSize; + i = (i + 1) / 2; + } + } while (startLoc && i > 1); + if (i == 1 + && (startLoc = read_pointer(&ptr, + ptr + tableSize, + hdr[3])) != 0 + && pc >= startLoc) + fde = (void *)read_pointer(&ptr, + ptr + + tableSize, + hdr[3]); + } + } + + if (fde != NULL) { + cie = cie_for_fde(fde, table); + ptr = (const u8 *)(fde + 2); + if (cie != NULL + && cie != &bad_cie + && cie != ¬_fde + && (ptrType = fde_pointer_type(cie)) >= 0 + && read_pointer(&ptr, + (const u8 *)(fde + 1) + *fde, + ptrType) == startLoc) { + if (!(ptrType & DW_EH_PE_indirect)) + ptrType &= + DW_EH_PE_FORM | DW_EH_PE_signed; + endLoc = + startLoc + read_pointer(&ptr, + (const u8 *)(fde + + 1) + + *fde, ptrType); + if (pc >= endLoc) + fde = NULL; + } else + fde = NULL; + } + if (fde == NULL) { + for (fde = table->address, tableSize = table->size; + cie = NULL, tableSize > sizeof(*fde) + && tableSize - sizeof(*fde) >= *fde; + tableSize -= sizeof(*fde) + *fde, + fde += 1 + *fde / sizeof(*fde)) { + cie = cie_for_fde(fde, table); + if (cie == &bad_cie) { + cie = NULL; + break; + } + if (cie == NULL + || cie == ¬_fde + || (ptrType = fde_pointer_type(cie)) < 0) + continue; + ptr = (const u8 *)(fde + 2); + startLoc = read_pointer(&ptr, + (const u8 *)(fde + 1) + + *fde, ptrType); + if (!startLoc) + continue; + if (!(ptrType & DW_EH_PE_indirect)) + ptrType &= + DW_EH_PE_FORM | DW_EH_PE_signed; + endLoc = + startLoc + read_pointer(&ptr, + (const u8 *)(fde + + 1) + + *fde, ptrType); + if (pc >= startLoc && pc < endLoc) + break; + } + } + } + if (cie != NULL) { + memset(&state, 0, sizeof(state)); + state.cieEnd = ptr; /* keep here temporarily */ + ptr = (const u8 *)(cie + 2); + end = (const u8 *)(cie + 1) + *cie; + frame->call_frame = 1; + if ((state.version = *ptr) != 1) + cie = NULL; /* unsupported version */ + else if (*++ptr) { + /* check if augmentation size is first (thus present) */ + if (*ptr == 'z') { + while (++ptr < end && *ptr) { + switch (*ptr) { + /* chk for ignorable or already handled + * nul-terminated augmentation string */ + case 'L': + case 'P': + case 'R': + continue; + case 'S': + frame->call_frame = 0; + continue; + default: + break; + } + break; + } + } + if (ptr >= end || *ptr) + cie = NULL; + } + ++ptr; + } + if (cie != NULL) { + /* get code aligment factor */ + state.codeAlign = get_uleb128(&ptr, end); + /* get data aligment factor */ + state.dataAlign = get_sleb128(&ptr, end); + if (state.codeAlign == 0 || state.dataAlign == 0 || ptr >= end) + cie = NULL; + else { + retAddrReg = + state.version <= 1 ? *ptr++ : get_uleb128(&ptr, + end); + unw_debug("CIE Frame Info:\n"); + unw_debug("return Address register 0x%lx\n", + retAddrReg); + unw_debug("data Align: %ld\n", state.dataAlign); + unw_debug("code Align: %lu\n", state.codeAlign); + /* skip augmentation */ + if (((const char *)(cie + 2))[1] == 'z') { + uleb128_t augSize = get_uleb128(&ptr, end); + + ptr += augSize; + } + if (ptr > end || retAddrReg >= ARRAY_SIZE(reg_info) + || REG_INVALID(retAddrReg) + || reg_info[retAddrReg].width != + sizeof(unsigned long)) + cie = NULL; + } + } + if (cie != NULL) { + state.cieStart = ptr; + ptr = state.cieEnd; + state.cieEnd = end; + end = (const u8 *)(fde + 1) + *fde; + /* skip augmentation */ + if (((const char *)(cie + 2))[1] == 'z') { + uleb128_t augSize = get_uleb128(&ptr, end); + + if ((ptr += augSize) > end) + fde = NULL; + } + } + if (cie == NULL || fde == NULL) { +#ifdef CONFIG_FRAME_POINTER + unsigned long top, bottom; + + top = STACK_TOP_UNW(frame->task); + bottom = STACK_BOTTOM_UNW(frame->task); +#if FRAME_RETADDR_OFFSET < 0 + if (UNW_SP(frame) < top && UNW_FP(frame) <= UNW_SP(frame) + && bottom < UNW_FP(frame) +#else + if (UNW_SP(frame) > top && UNW_FP(frame) >= UNW_SP(frame) + && bottom > UNW_FP(frame) +#endif + && !((UNW_SP(frame) | UNW_FP(frame)) + & (sizeof(unsigned long) - 1))) { + unsigned long link; + + if (!__get_user(link, (unsigned long *) + (UNW_FP(frame) + FRAME_LINK_OFFSET)) +#if FRAME_RETADDR_OFFSET < 0 + && link > bottom && link < UNW_FP(frame) +#else + && link > UNW_FP(frame) && link < bottom +#endif + && !(link & (sizeof(link) - 1)) + && !__get_user(UNW_PC(frame), + (unsigned long *)(UNW_FP(frame) + + FRAME_RETADDR_OFFSET))) + { + UNW_SP(frame) = + UNW_FP(frame) + FRAME_RETADDR_OFFSET +#if FRAME_RETADDR_OFFSET < 0 + - +#else + + +#endif + sizeof(UNW_PC(frame)); + UNW_FP(frame) = link; + return 0; + } + } +#endif + return -ENXIO; + } + state.org = startLoc; + memcpy(&state.cfa, &badCFA, sizeof(state.cfa)); + + unw_debug("\nProcess instructions\n"); + + /* process instructions + * For ARC, we optimize by having blink(retAddrReg) with + * the sameValue in the leaf function, so we should not check + * state.regs[retAddrReg].where == Nowhere + */ + if (!processCFI(ptr, end, pc, ptrType, &state) + || state.loc > endLoc +/* || state.regs[retAddrReg].where == Nowhere */ + || state.cfa.reg >= ARRAY_SIZE(reg_info) + || reg_info[state.cfa.reg].width != sizeof(unsigned long) + || state.cfa.offs % sizeof(unsigned long)) + return -EIO; + +#ifdef UNWIND_DEBUG + unw_debug("\n"); + + unw_debug("\nRegister State Based on the rules parsed from FDE:\n"); + for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { + + if (REG_INVALID(i)) + continue; + + switch (state.regs[i].where) { + case Nowhere: + break; + case Memory: + unw_debug(" r%d: c(%lu),", i, state.regs[i].value); + break; + case Register: + unw_debug(" r%d: r(%lu),", i, state.regs[i].value); + break; + case Value: + unw_debug(" r%d: v(%lu),", i, state.regs[i].value); + break; + } + } + + unw_debug("\n"); +#endif + + /* update frame */ +#ifndef CONFIG_AS_CFI_SIGNAL_FRAME + if (frame->call_frame + && !UNW_DEFAULT_RA(state.regs[retAddrReg], state.dataAlign)) + frame->call_frame = 0; +#endif + cfa = FRAME_REG(state.cfa.reg, unsigned long) + state.cfa.offs; + startLoc = min_t(unsigned long, UNW_SP(frame), cfa); + endLoc = max_t(unsigned long, UNW_SP(frame), cfa); + if (STACK_LIMIT(startLoc) != STACK_LIMIT(endLoc)) { + startLoc = min(STACK_LIMIT(cfa), cfa); + endLoc = max(STACK_LIMIT(cfa), cfa); + } + + unw_debug("\nCFA reg: 0x%lx, offset: 0x%lx => 0x%lx\n", + state.cfa.reg, state.cfa.offs, cfa); + + for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { + if (REG_INVALID(i)) { + if (state.regs[i].where == Nowhere) + continue; + return -EIO; + } + switch (state.regs[i].where) { + default: + break; + case Register: + if (state.regs[i].value >= ARRAY_SIZE(reg_info) + || REG_INVALID(state.regs[i].value) + || reg_info[i].width > + reg_info[state.regs[i].value].width) + return -EIO; + switch (reg_info[state.regs[i].value].width) { + case sizeof(u8): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u8); + break; + case sizeof(u16): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u16); + break; + case sizeof(u32): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u32); + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u64); + break; +#endif + default: + return -EIO; + } + break; + } + } + + unw_debug("\nRegister state after evaluation with realtime Stack:\n"); + fptr = (unsigned long *)(&frame->regs); + for (i = 0; i < ARRAY_SIZE(state.regs); ++i, fptr++) { + + if (REG_INVALID(i)) + continue; + switch (state.regs[i].where) { + case Nowhere: + if (reg_info[i].width != sizeof(UNW_SP(frame)) + || &FRAME_REG(i, __typeof__(UNW_SP(frame))) + != &UNW_SP(frame)) + continue; + UNW_SP(frame) = cfa; + break; + case Register: + switch (reg_info[i].width) { + case sizeof(u8): + FRAME_REG(i, u8) = state.regs[i].value; + break; + case sizeof(u16): + FRAME_REG(i, u16) = state.regs[i].value; + break; + case sizeof(u32): + FRAME_REG(i, u32) = state.regs[i].value; + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + FRAME_REG(i, u64) = state.regs[i].value; + break; +#endif + default: + return -EIO; + } + break; + case Value: + if (reg_info[i].width != sizeof(unsigned long)) + return -EIO; + FRAME_REG(i, unsigned long) = cfa + state.regs[i].value + * state.dataAlign; + break; + case Memory: + addr = cfa + state.regs[i].value * state.dataAlign; + + if ((state.regs[i].value * state.dataAlign) + % sizeof(unsigned long) + || addr < startLoc + || addr + sizeof(unsigned long) < addr + || addr + sizeof(unsigned long) > endLoc) + return -EIO; + + switch (reg_info[i].width) { + case sizeof(u8): + __get_user(FRAME_REG(i, u8), + (u8 __user *)addr); + break; + case sizeof(u16): + __get_user(FRAME_REG(i, u16), + (u16 __user *)addr); + break; + case sizeof(u32): + __get_user(FRAME_REG(i, u32), + (u32 __user *)addr); + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + __get_user(FRAME_REG(i, u64), + (u64 __user *)addr); + break; +#endif + default: + return -EIO; + } + + break; + } + unw_debug("r%d: 0x%lx ", i, *fptr); + } + + return 0; +#undef FRAME_REG +} +EXPORT_SYMBOL(arc_unwind); diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S new file mode 100644 index 00000000000..d3c92f52d44 --- /dev/null +++ b/arch/arc/kernel/vmlinux.lds.S @@ -0,0 +1,163 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <asm-generic/vmlinux.lds.h> +#include <asm/cache.h> +#include <asm/page.h> +#include <asm/thread_info.h> + +OUTPUT_ARCH(arc) +ENTRY(_stext) + +#ifdef CONFIG_CPU_BIG_ENDIAN +jiffies = jiffies_64 + 4; +#else +jiffies = jiffies_64; +#endif + +SECTIONS +{ + /* + * ICCM starts at 0x8000_0000. So if kernel is relocated to some other + * address, make sure peripheral at 0x8z doesn't clash with ICCM + * Essentially vector is also in ICCM. + */ + + . = CONFIG_LINUX_LINK_BASE; + + _int_vec_base_lds = .; + .vector : { + *(.vector) + . = ALIGN(PAGE_SIZE); + } + +#ifdef CONFIG_ARC_HAS_ICCM + .text.arcfp : { + *(.text.arcfp) + . = ALIGN(CONFIG_ARC_ICCM_SZ * 1024); + } +#endif + + /* + * The reason for having a seperate subsection .init.ramfs is to + * prevent objump from including it in kernel dumps + * + * Reason for having .init.ramfs above .init is to make sure that the + * binary blob is tucked away to one side, reducing the displacement + * between .init.text and .text, avoiding any possible relocation + * errors because of calls from .init.text to .text + * Yes such calls do exist. e.g. + * decompress_inflate.c:gunzip( ) -> zlib_inflate_workspace( ) + */ + + __init_begin = .; + + .init.ramfs : { INIT_RAM_FS } + + . = ALIGN(PAGE_SIZE); + _stext = .; + + HEAD_TEXT_SECTION + INIT_TEXT_SECTION(L1_CACHE_BYTES) + + /* INIT_DATA_SECTION open-coded: special INIT_RAM_FS handling */ + .init.data : { + INIT_DATA + INIT_SETUP(L1_CACHE_BYTES) + INIT_CALLS + CON_INITCALL + SECURITY_INITCALL + } + + .init.arch.info : { + __arch_info_begin = .; + *(.arch.info.init) + __arch_info_end = .; + } + + PERCPU_SECTION(L1_CACHE_BYTES) + + /* + * .exit.text is discard at runtime, not link time, to deal with + * references from .debug_frame + * It will be init freed, being inside [__init_start : __init_end] + */ + .exit.text : { EXIT_TEXT } + .exit.data : { EXIT_DATA } + + . = ALIGN(PAGE_SIZE); + __init_end = .; + + .text : { + _text = .; + TEXT_TEXT + SCHED_TEXT + LOCK_TEXT + KPROBES_TEXT + *(.fixup) + *(.gnu.warning) + } + EXCEPTION_TABLE(L1_CACHE_BYTES) + _etext = .; + + _sdata = .; + RO_DATA_SECTION(PAGE_SIZE) + + /* + * 1. this is .data essentially + * 2. THREAD_SIZE for init.task, must be kernel-stk sz aligned + */ + RW_DATA_SECTION(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE) + + _edata = .; + + BSS_SECTION(0, 0, 0) + +#ifdef CONFIG_ARC_DW2_UNWIND + . = ALIGN(PAGE_SIZE); + .debug_frame : { + __start_unwind = .; + *(.debug_frame) + __end_unwind = .; + } +#else + /DISCARD/ : { *(.debug_frame) } +#endif + + NOTES + + . = ALIGN(PAGE_SIZE); + _end = . ; + + STABS_DEBUG + DISCARDS + + .arcextmap 0 : { + *(.gnu.linkonce.arcextmap.*) + *(.arcextmap.*) + } + + /* open-coded because we need .debug_frame seperately for unwinding */ + .debug_aranges 0 : { *(.debug_aranges) } + .debug_pubnames 0 : { *(.debug_pubnames) } + .debug_info 0 : { *(.debug_info) } + .debug_abbrev 0 : { *(.debug_abbrev) } + .debug_line 0 : { *(.debug_line) } + .debug_str 0 : { *(.debug_str) } + .debug_loc 0 : { *(.debug_loc) } + .debug_macinfo 0 : { *(.debug_macinfo) } + +#ifdef CONFIG_ARC_HAS_DCCM + . = CONFIG_ARC_DCCM_BASE; + __arc_dccm_base = .; + .data.arcfp : { + *(.data.arcfp) + } + . = ALIGN(CONFIG_ARC_DCCM_SZ * 1024); +#endif +} |