/* * Copyright IBM Corp. 2004,2011 * Author(s): Martin Schwidefsky , * Holger Smolinski , * Thomas Spatzier , * * This file contains interrupt related functions. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "entry.h" struct irq_class { char *name; char *desc; }; static const struct irq_class intrclass_names[] = { {.name = "EXT" }, {.name = "I/O" }, {.name = "CLK", .desc = "[EXT] Clock Comparator" }, {.name = "EXC", .desc = "[EXT] External Call" }, {.name = "EMS", .desc = "[EXT] Emergency Signal" }, {.name = "TMR", .desc = "[EXT] CPU Timer" }, {.name = "TAL", .desc = "[EXT] Timing Alert" }, {.name = "PFL", .desc = "[EXT] Pseudo Page Fault" }, {.name = "DSD", .desc = "[EXT] DASD Diag" }, {.name = "VRT", .desc = "[EXT] Virtio" }, {.name = "SCP", .desc = "[EXT] Service Call" }, {.name = "IUC", .desc = "[EXT] IUCV" }, {.name = "CPM", .desc = "[EXT] CPU Measurement" }, {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt" }, {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt" }, {.name = "DAS", .desc = "[I/O] DASD" }, {.name = "C15", .desc = "[I/O] 3215" }, {.name = "C70", .desc = "[I/O] 3270" }, {.name = "TAP", .desc = "[I/O] Tape" }, {.name = "VMR", .desc = "[I/O] Unit Record Devices" }, {.name = "LCS", .desc = "[I/O] LCS" }, {.name = "CLW", .desc = "[I/O] CLAW" }, {.name = "CTC", .desc = "[I/O] CTC" }, {.name = "APB", .desc = "[I/O] AP Bus" }, {.name = "CSC", .desc = "[I/O] CHSC Subchannel" }, {.name = "NMI", .desc = "[NMI] Machine Check" }, }; /* * show_interrupts is needed by /proc/interrupts. */ int show_interrupts(struct seq_file *p, void *v) { int i = *(loff_t *) v, j; get_online_cpus(); if (i == 0) { seq_puts(p, " "); for_each_online_cpu(j) seq_printf(p, "CPU%d ",j); seq_putc(p, '\n'); } if (i < NR_IRQS) { seq_printf(p, "%s: ", intrclass_names[i].name); #ifndef CONFIG_SMP seq_printf(p, "%10u ", kstat_irqs(i)); #else for_each_online_cpu(j) seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); #endif if (intrclass_names[i].desc) seq_printf(p, " %s", intrclass_names[i].desc); seq_putc(p, '\n'); } put_online_cpus(); return 0; } /* * Switch to the asynchronous interrupt stack for softirq execution. */ asmlinkage void do_softirq(void) { unsigned long flags, old, new; if (in_interrupt()) return; local_irq_save(flags); if (local_softirq_pending()) { /* Get current stack pointer. */ asm volatile("la %0,0(15)" : "=a" (old)); /* Check against async. stack address range. */ new = S390_lowcore.async_stack; if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) { /* Need to switch to the async. stack. */ new -= STACK_FRAME_OVERHEAD; ((struct stack_frame *) new)->back_chain = old; asm volatile(" la 15,0(%0)\n" " basr 14,%2\n" " la 15,0(%1)\n" : : "a" (new), "a" (old), "a" (__do_softirq) : "0", "1", "2", "3", "4", "5", "14", "cc", "memory" ); } else /* We are already on the async stack. */ __do_softirq(); } local_irq_restore(flags); } #ifdef CONFIG_PROC_FS void init_irq_proc(void) { struct proc_dir_entry *root_irq_dir; root_irq_dir = proc_mkdir("irq", NULL); create_prof_cpu_mask(root_irq_dir); } #endif /* * ext_int_hash[index] is the list head for all external interrupts that hash * to this index. */ static struct list_head ext_int_hash[256]; struct ext_int_info { ext_int_handler_t handler; u16 code; struct list_head entry; struct rcu_head rcu; }; /* ext_int_hash_lock protects the handler lists for external interrupts */ DEFINE_SPINLOCK(ext_int_hash_lock); static void __init init_external_interrupts(void) { int idx; for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++) INIT_LIST_HEAD(&ext_int_hash[idx]); } static inline int ext_hash(u16 code) { return (code + (code >> 9)) & 0xff; } static void ext_int_hash_update(struct rcu_head *head) { struct ext_int_info *p = container_of(head, struct ext_int_info, rcu); kfree(p); } int register_external_interrupt(u16 code, ext_int_handler_t handler) { struct ext_int_info *p; unsigned long flags; int index; p = kmalloc(sizeof(*p), GFP_ATOMIC); if (!p) return -ENOMEM; p->code = code; p->handler = handler; index = ext_hash(code); spin_lock_irqsave(&ext_int_hash_lock, flags); list_add_rcu(&p->entry, &ext_int_hash[index]); spin_unlock_irqrestore(&ext_int_hash_lock, flags); return 0; } EXPORT_SYMBOL(register_external_interrupt); int unregister_external_interrupt(u16 code, ext_int_handler_t handler) { struct ext_int_info *p; unsigned long flags; int index = ext_hash(code); spin_lock_irqsave(&ext_int_hash_lock, flags); list_for_each_entry_rcu(p, &ext_int_hash[index], entry) if (p->code == code && p->handler == handler) { list_del_rcu(&p->entry); call_rcu(&p->rcu, ext_int_hash_update); } spin_unlock_irqrestore(&ext_int_hash_lock, flags); return 0; } EXPORT_SYMBOL(unregister_external_interrupt); void __irq_entry do_extint(struct pt_regs *regs, unsigned int ext_int_code, unsigned int param32, unsigned long param64) { struct pt_regs *old_regs; unsigned short code; struct ext_int_info *p; int index; code = (unsigned short) ext_int_code; old_regs = set_irq_regs(regs); s390_idle_check(regs, S390_lowcore.int_clock, S390_lowcore.async_enter_timer); irq_enter(); if (S390_lowcore.int_clock >= S390_lowcore.clock_comparator) /* Serve timer interrupts first. */ clock_comparator_work(); kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++; if (code != 0x1004) __get_cpu_var(s390_idle).nohz_delay = 1; index = ext_hash(code); rcu_read_lock(); list_for_each_entry_rcu(p, &ext_int_hash[index], entry) if (likely(p->code == code)) p->handler(ext_int_code, param32, param64); rcu_read_unlock(); irq_exit(); set_irq_regs(old_regs); } void __init init_IRQ(void) { init_external_interrupts(); } static DEFINE_SPINLOCK(sc_irq_lock); static int sc_irq_refcount; void service_subclass_irq_register(void) { spin_lock(&sc_irq_lock); if (!sc_irq_refcount) ctl_set_bit(0, 9); sc_irq_refcount++; spin_unlock(&sc_irq_lock); } EXPORT_SYMBOL(service_subclass_irq_register); void service_subclass_irq_unregister(void) { spin_lock(&sc_irq_lock); sc_irq_refcount--; if (!sc_irq_refcount) ctl_clear_bit(0, 9); spin_unlock(&sc_irq_lock); } EXPORT_SYMBOL(service_subclass_irq_unregister);