aboutsummaryrefslogtreecommitdiff
path: root/arch/arc/mm/tlb.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arc/mm/tlb.c')
-rw-r--r--arch/arc/mm/tlb.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
new file mode 100644
index 00000000000..9b9ce23f4ec
--- /dev/null
+++ b/arch/arc/mm/tlb.c
@@ -0,0 +1,645 @@
+/*
+ * TLB Management (flush/create/diagnostics) for ARC700
+ *
+ * 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 2011
+ * -Reintroduce duplicate PD fixup - some customer chips still have the issue
+ *
+ * vineetg: May 2011
+ * -No need to flush_cache_page( ) for each call to update_mmu_cache()
+ * some of the LMBench tests improved amazingly
+ * = page-fault thrice as fast (75 usec to 28 usec)
+ * = mmap twice as fast (9.6 msec to 4.6 msec),
+ * = fork (5.3 msec to 3.7 msec)
+ *
+ * vineetg: April 2011 :
+ * -MMU v3: PD{0,1} bits layout changed: They don't overlap anymore,
+ * helps avoid a shift when preparing PD0 from PTE
+ *
+ * vineetg: April 2011 : Preparing for MMU V3
+ * -MMU v2/v3 BCRs decoded differently
+ * -Remove TLB_SIZE hardcoding as it's variable now: 256 or 512
+ * -tlb_entry_erase( ) can be void
+ * -local_flush_tlb_range( ):
+ * = need not "ceil" @end
+ * = walks MMU only if range spans < 32 entries, as opposed to 256
+ *
+ * Vineetg: Sept 10th 2008
+ * -Changes related to MMU v2 (Rel 4.8)
+ *
+ * Vineetg: Aug 29th 2008
+ * -In TLB Flush operations (Metal Fix MMU) there is a explict command to
+ * flush Micro-TLBS. If TLB Index Reg is invalid prior to TLBIVUTLB cmd,
+ * it fails. Thus need to load it with ANY valid value before invoking
+ * TLBIVUTLB cmd
+ *
+ * Vineetg: Aug 21th 2008:
+ * -Reduced the duration of IRQ lockouts in TLB Flush routines
+ * -Multiple copies of TLB erase code seperated into a "single" function
+ * -In TLB Flush routines, interrupt disabling moved UP to retrieve ASID
+ * in interrupt-safe region.
+ *
+ * Vineetg: April 23rd Bug #93131
+ * Problem: tlb_flush_kernel_range() doesnt do anything if the range to
+ * flush is more than the size of TLB itself.
+ *
+ * Rahul Trivedi : Codito Technologies 2004
+ */
+
+#include <linux/module.h>
+#include <asm/arcregs.h>
+#include <asm/setup.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+
+/* Need for ARC MMU v2
+ *
+ * ARC700 MMU-v1 had a Joint-TLB for Code and Data and is 2 way set-assoc.
+ * For a memcpy operation with 3 players (src/dst/code) such that all 3 pages
+ * map into same set, there would be contention for the 2 ways causing severe
+ * Thrashing.
+ *
+ * Although J-TLB is 2 way set assoc, ARC700 caches J-TLB into uTLBS which has
+ * much higher associativity. u-D-TLB is 8 ways, u-I-TLB is 4 ways.
+ * Given this, the thrasing problem should never happen because once the 3
+ * J-TLB entries are created (even though 3rd will knock out one of the prev
+ * two), the u-D-TLB and u-I-TLB will have what is required to accomplish memcpy
+ *
+ * Yet we still see the Thrashing because a J-TLB Write cause flush of u-TLBs.
+ * This is a simple design for keeping them in sync. So what do we do?
+ * The solution which James came up was pretty neat. It utilised the assoc
+ * of uTLBs by not invalidating always but only when absolutely necessary.
+ *
+ * - Existing TLB commands work as before
+ * - New command (TLBWriteNI) for TLB write without clearing uTLBs
+ * - New command (TLBIVUTLB) to invalidate uTLBs.
+ *
+ * The uTLBs need only be invalidated when pages are being removed from the
+ * OS page table. If a 'victim' TLB entry is being overwritten in the main TLB
+ * as a result of a miss, the removed entry is still allowed to exist in the
+ * uTLBs as it is still valid and present in the OS page table. This allows the
+ * full associativity of the uTLBs to hide the limited associativity of the main
+ * TLB.
+ *
+ * During a miss handler, the new "TLBWriteNI" command is used to load
+ * entries without clearing the uTLBs.
+ *
+ * When the OS page table is updated, TLB entries that may be associated with a
+ * removed page are removed (flushed) from the TLB using TLBWrite. In this
+ * circumstance, the uTLBs must also be cleared. This is done by using the
+ * existing TLBWrite command. An explicit IVUTLB is also required for those
+ * corner cases when TLBWrite was not executed at all because the corresp
+ * J-TLB entry got evicted/replaced.
+ */
+
+/* A copy of the ASID from the PID reg is kept in asid_cache */
+int asid_cache = FIRST_ASID;
+
+/* ASID to mm struct mapping. We have one extra entry corresponding to
+ * NO_ASID to save us a compare when clearing the mm entry for old asid
+ * see get_new_mmu_context (asm-arc/mmu_context.h)
+ */
+struct mm_struct *asid_mm_map[NUM_ASID + 1];
+
+/*
+ * Utility Routine to erase a J-TLB entry
+ * The procedure is to look it up in the MMU. If found, ERASE it by
+ * issuing a TlbWrite CMD with PD0 = PD1 = 0
+ */
+
+static void __tlb_entry_erase(void)
+{
+ write_aux_reg(ARC_REG_TLBPD1, 0);
+ write_aux_reg(ARC_REG_TLBPD0, 0);
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
+}
+
+static void tlb_entry_erase(unsigned int vaddr_n_asid)
+{
+ unsigned int idx;
+
+ /* Locate the TLB entry for this vaddr + ASID */
+ write_aux_reg(ARC_REG_TLBPD0, vaddr_n_asid);
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe);
+ idx = read_aux_reg(ARC_REG_TLBINDEX);
+
+ /* No error means entry found, zero it out */
+ if (likely(!(idx & TLB_LKUP_ERR))) {
+ __tlb_entry_erase();
+ } else { /* Some sort of Error */
+
+ /* Duplicate entry error */
+ if (idx & 0x1) {
+ /* TODO we need to handle this case too */
+ pr_emerg("unhandled Duplicate flush for %x\n",
+ vaddr_n_asid);
+ }
+ /* else entry not found so nothing to do */
+ }
+}
+
+/****************************************************************************
+ * ARC700 MMU caches recently used J-TLB entries (RAM) as uTLBs (FLOPs)
+ *
+ * New IVUTLB cmd in MMU v2 explictly invalidates the uTLB
+ *
+ * utlb_invalidate ( )
+ * -For v2 MMU calls Flush uTLB Cmd
+ * -For v1 MMU does nothing (except for Metal Fix v1 MMU)
+ * This is because in v1 TLBWrite itself invalidate uTLBs
+ ***************************************************************************/
+
+static void utlb_invalidate(void)
+{
+#if (CONFIG_ARC_MMU_VER >= 2)
+
+#if (CONFIG_ARC_MMU_VER < 3)
+ /* MMU v2 introduced the uTLB Flush command.
+ * There was however an obscure hardware bug, where uTLB flush would
+ * fail when a prior probe for J-TLB (both totally unrelated) would
+ * return lkup err - because the entry didnt exist in MMU.
+ * The Workround was to set Index reg with some valid value, prior to
+ * flush. This was fixed in MMU v3 hence not needed any more
+ */
+ unsigned int idx;
+
+ /* make sure INDEX Reg is valid */
+ idx = read_aux_reg(ARC_REG_TLBINDEX);
+
+ /* If not write some dummy val */
+ if (unlikely(idx & TLB_LKUP_ERR))
+ write_aux_reg(ARC_REG_TLBINDEX, 0xa);
+#endif
+
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBIVUTLB);
+#endif
+
+}
+
+/*
+ * Un-conditionally (without lookup) erase the entire MMU contents
+ */
+
+noinline void local_flush_tlb_all(void)
+{
+ unsigned long flags;
+ unsigned int entry;
+ struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
+
+ local_irq_save(flags);
+
+ /* Load PD0 and PD1 with template for a Blank Entry */
+ write_aux_reg(ARC_REG_TLBPD1, 0);
+ write_aux_reg(ARC_REG_TLBPD0, 0);
+
+ for (entry = 0; entry < mmu->num_tlb; entry++) {
+ /* write this entry to the TLB */
+ write_aux_reg(ARC_REG_TLBINDEX, entry);
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
+ }
+
+ utlb_invalidate();
+
+ local_irq_restore(flags);
+}
+
+/*
+ * Flush the entrie MM for userland. The fastest way is to move to Next ASID
+ */
+noinline void local_flush_tlb_mm(struct mm_struct *mm)
+{
+ /*
+ * Small optimisation courtesy IA64
+ * flush_mm called during fork,exit,munmap etc, multiple times as well.
+ * Only for fork( ) do we need to move parent to a new MMU ctxt,
+ * all other cases are NOPs, hence this check.
+ */
+ if (atomic_read(&mm->mm_users) == 0)
+ return;
+
+ /*
+ * Workaround for Android weirdism:
+ * A binder VMA could end up in a task such that vma->mm != tsk->mm
+ * old code would cause h/w - s/w ASID to get out of sync
+ */
+ if (current->mm != mm)
+ destroy_context(mm);
+ else
+ get_new_mmu_context(mm);
+}
+
+/*
+ * Flush a Range of TLB entries for userland.
+ * @start is inclusive, while @end is exclusive
+ * Difference between this and Kernel Range Flush is
+ * -Here the fastest way (if range is too large) is to move to next ASID
+ * without doing any explicit Shootdown
+ * -In case of kernel Flush, entry has to be shot down explictly
+ */
+void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ unsigned long flags;
+ unsigned int asid;
+
+ /* If range @start to @end is more than 32 TLB entries deep,
+ * its better to move to a new ASID rather than searching for
+ * individual entries and then shooting them down
+ *
+ * The calc above is rough, doesn't account for unaligned parts,
+ * since this is heuristics based anyways
+ */
+ if (unlikely((end - start) >= PAGE_SIZE * 32)) {
+ local_flush_tlb_mm(vma->vm_mm);
+ return;
+ }
+
+ /*
+ * @start moved to page start: this alone suffices for checking
+ * loop end condition below, w/o need for aligning @end to end
+ * e.g. 2000 to 4001 will anyhow loop twice
+ */
+ start &= PAGE_MASK;
+
+ local_irq_save(flags);
+ asid = vma->vm_mm->context.asid;
+
+ if (asid != NO_ASID) {
+ while (start < end) {
+ tlb_entry_erase(start | (asid & 0xff));
+ start += PAGE_SIZE;
+ }
+ }
+
+ utlb_invalidate();
+
+ local_irq_restore(flags);
+}
+
+/* Flush the kernel TLB entries - vmalloc/modules (Global from MMU perspective)
+ * @start, @end interpreted as kvaddr
+ * Interestingly, shared TLB entries can also be flushed using just
+ * @start,@end alone (interpreted as user vaddr), although technically SASID
+ * is also needed. However our smart TLbProbe lookup takes care of that.
+ */
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ unsigned long flags;
+
+ /* exactly same as above, except for TLB entry not taking ASID */
+
+ if (unlikely((end - start) >= PAGE_SIZE * 32)) {
+ local_flush_tlb_all();
+ return;
+ }
+
+ start &= PAGE_MASK;
+
+ local_irq_save(flags);
+ while (start < end) {
+ tlb_entry_erase(start);
+ start += PAGE_SIZE;
+ }
+
+ utlb_invalidate();
+
+ local_irq_restore(flags);
+}
+
+/*
+ * Delete TLB entry in MMU for a given page (??? address)
+ * NOTE One TLB entry contains translation for single PAGE
+ */
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+ unsigned long flags;
+
+ /* Note that it is critical that interrupts are DISABLED between
+ * checking the ASID and using it flush the TLB entry
+ */
+ local_irq_save(flags);
+
+ if (vma->vm_mm->context.asid != NO_ASID) {
+ tlb_entry_erase((page & PAGE_MASK) |
+ (vma->vm_mm->context.asid & 0xff));
+ utlb_invalidate();
+ }
+
+ local_irq_restore(flags);
+}
+
+/*
+ * Routine to create a TLB entry
+ */
+void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
+{
+ unsigned long flags;
+ unsigned int idx, asid_or_sasid;
+ unsigned long pd0_flags;
+
+ /*
+ * create_tlb() assumes that current->mm == vma->mm, since
+ * -it ASID for TLB entry is fetched from MMU ASID reg (valid for curr)
+ * -completes the lazy write to SASID reg (again valid for curr tsk)
+ *
+ * Removing the assumption involves
+ * -Using vma->mm->context{ASID,SASID}, as opposed to MMU reg.
+ * -Fix the TLB paranoid debug code to not trigger false negatives.
+ * -More importantly it makes this handler inconsistent with fast-path
+ * TLB Refill handler which always deals with "current"
+ *
+ * Lets see the use cases when current->mm != vma->mm and we land here
+ * 1. execve->copy_strings()->__get_user_pages->handle_mm_fault
+ * Here VM wants to pre-install a TLB entry for user stack while
+ * current->mm still points to pre-execve mm (hence the condition).
+ * However the stack vaddr is soon relocated (randomization) and
+ * move_page_tables() tries to undo that TLB entry.
+ * Thus not creating TLB entry is not any worse.
+ *
+ * 2. ptrace(POKETEXT) causes a CoW - debugger(current) inserting a
+ * breakpoint in debugged task. Not creating a TLB now is not
+ * performance critical.
+ *
+ * Both the cases above are not good enough for code churn.
+ */
+ if (current->active_mm != vma->vm_mm)
+ return;
+
+ local_irq_save(flags);
+
+ tlb_paranoid_check(vma->vm_mm->context.asid, address);
+
+ address &= PAGE_MASK;
+
+ /* update this PTE credentials */
+ pte_val(*ptep) |= (_PAGE_PRESENT | _PAGE_ACCESSED);
+
+ /* Create HW TLB entry Flags (in PD0) from PTE Flags */
+#if (CONFIG_ARC_MMU_VER <= 2)
+ pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0) >> 1);
+#else
+ pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0));
+#endif
+
+ /* ASID for this task */
+ asid_or_sasid = read_aux_reg(ARC_REG_PID) & 0xff;
+
+ write_aux_reg(ARC_REG_TLBPD0, address | pd0_flags | asid_or_sasid);
+
+ /* Load remaining info in PD1 (Page Frame Addr and Kx/Kw/Kr Flags) */
+ write_aux_reg(ARC_REG_TLBPD1, (pte_val(*ptep) & PTE_BITS_IN_PD1));
+
+ /* First verify if entry for this vaddr+ASID already exists */
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe);
+ idx = read_aux_reg(ARC_REG_TLBINDEX);
+
+ /*
+ * If Not already present get a free slot from MMU.
+ * Otherwise, Probe would have located the entry and set INDEX Reg
+ * with existing location. This will cause Write CMD to over-write
+ * existing entry with new PD0 and PD1
+ */
+ if (likely(idx & TLB_LKUP_ERR))
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBGetIndex);
+
+ /*
+ * Commit the Entry to MMU
+ * It doesnt sound safe to use the TLBWriteNI cmd here
+ * which doesn't flush uTLBs. I'd rather be safe than sorry.
+ */
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
+
+ local_irq_restore(flags);
+}
+
+/* arch hook called by core VM at the end of handle_mm_fault( ),
+ * when a new PTE is entered in Page Tables or an existing one
+ * is modified. We aggresively pre-install a TLB entry
+ */
+
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long vaddress,
+ pte_t *ptep)
+{
+
+ create_tlb(vma, vaddress, ptep);
+}
+
+/* Read the Cache Build Confuration Registers, Decode them and save into
+ * the cpuinfo structure for later use.
+ * No Validation is done here, simply read/convert the BCRs
+ */
+void __init read_decode_mmu_bcr(void)
+{
+ unsigned int tmp;
+ struct bcr_mmu_1_2 *mmu2; /* encoded MMU2 attr */
+ struct bcr_mmu_3 *mmu3; /* encoded MMU3 attr */
+ struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
+
+ tmp = read_aux_reg(ARC_REG_MMU_BCR);
+ mmu->ver = (tmp >> 24);
+
+ if (mmu->ver <= 2) {
+ mmu2 = (struct bcr_mmu_1_2 *)&tmp;
+ mmu->pg_sz = PAGE_SIZE;
+ mmu->sets = 1 << mmu2->sets;
+ mmu->ways = 1 << mmu2->ways;
+ mmu->u_dtlb = mmu2->u_dtlb;
+ mmu->u_itlb = mmu2->u_itlb;
+ } else {
+ mmu3 = (struct bcr_mmu_3 *)&tmp;
+ mmu->pg_sz = 512 << mmu3->pg_sz;
+ mmu->sets = 1 << mmu3->sets;
+ mmu->ways = 1 << mmu3->ways;
+ mmu->u_dtlb = mmu3->u_dtlb;
+ mmu->u_itlb = mmu3->u_itlb;
+ }
+
+ mmu->num_tlb = mmu->sets * mmu->ways;
+}
+
+char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len)
+{
+ int n = 0;
+ struct cpuinfo_arc_mmu *p_mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
+
+ n += scnprintf(buf + n, len - n, "ARC700 MMU [v%x]\t: %dk PAGE, ",
+ p_mmu->ver, TO_KB(p_mmu->pg_sz));
+
+ n += scnprintf(buf + n, len - n,
+ "J-TLB %d (%dx%d), uDTLB %d, uITLB %d, %s\n",
+ p_mmu->num_tlb, p_mmu->sets, p_mmu->ways,
+ p_mmu->u_dtlb, p_mmu->u_itlb,
+ __CONFIG_ARC_MMU_SASID_VAL ? "SASID" : "");
+
+ return buf;
+}
+
+void __init arc_mmu_init(void)
+{
+ char str[256];
+ struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
+
+ printk(arc_mmu_mumbojumbo(0, str, sizeof(str)));
+
+ /* For efficiency sake, kernel is compile time built for a MMU ver
+ * This must match the hardware it is running on.
+ * Linux built for MMU V2, if run on MMU V1 will break down because V1
+ * hardware doesn't understand cmds such as WriteNI, or IVUTLB
+ * On the other hand, Linux built for V1 if run on MMU V2 will do
+ * un-needed workarounds to prevent memcpy thrashing.
+ * Similarly MMU V3 has new features which won't work on older MMU
+ */
+ if (mmu->ver != CONFIG_ARC_MMU_VER) {
+ panic("MMU ver %d doesn't match kernel built for %d...\n",
+ mmu->ver, CONFIG_ARC_MMU_VER);
+ }
+
+ if (mmu->pg_sz != PAGE_SIZE)
+ panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE));
+
+ /*
+ * ASID mgmt data structures are compile time init
+ * asid_cache = FIRST_ASID and asid_mm_map[] all zeroes
+ */
+
+ local_flush_tlb_all();
+
+ /* Enable the MMU */
+ write_aux_reg(ARC_REG_PID, MMU_ENABLE);
+
+ /* In smp we use this reg for interrupt 1 scratch */
+#ifndef CONFIG_SMP
+ /* swapper_pg_dir is the pgd for the kernel, used by vmalloc */
+ write_aux_reg(ARC_REG_SCRATCH_DATA0, swapper_pg_dir);
+#endif
+}
+
+/*
+ * TLB Programmer's Model uses Linear Indexes: 0 to {255, 511} for 128 x {2,4}
+ * The mapping is Column-first.
+ * --------------------- -----------
+ * |way0|way1|way2|way3| |way0|way1|
+ * --------------------- -----------
+ * [set0] | 0 | 1 | 2 | 3 | | 0 | 1 |
+ * [set1] | 4 | 5 | 6 | 7 | | 2 | 3 |
+ * ~ ~ ~ ~
+ * [set127] | 508| 509| 510| 511| | 254| 255|
+ * --------------------- -----------
+ * For normal operations we don't(must not) care how above works since
+ * MMU cmd getIndex(vaddr) abstracts that out.
+ * However for walking WAYS of a SET, we need to know this
+ */
+#define SET_WAY_TO_IDX(mmu, set, way) ((set) * mmu->ways + (way))
+
+/* Handling of Duplicate PD (TLB entry) in MMU.
+ * -Could be due to buggy customer tapeouts or obscure kernel bugs
+ * -MMU complaints not at the time of duplicate PD installation, but at the
+ * time of lookup matching multiple ways.
+ * -Ideally these should never happen - but if they do - workaround by deleting
+ * the duplicate one.
+ * -Knob to be verbose abt it.(TODO: hook them up to debugfs)
+ */
+volatile int dup_pd_verbose = 1;/* Be slient abt it or complain (default) */
+
+void do_tlb_overlap_fault(unsigned long cause, unsigned long address,
+ struct pt_regs *regs)
+{
+ int set, way, n;
+ unsigned int pd0[4], pd1[4]; /* assume max 4 ways */
+ unsigned long flags, is_valid;
+ struct cpuinfo_arc_mmu *mmu = &cpuinfo_arc700[smp_processor_id()].mmu;
+
+ local_irq_save(flags);
+
+ /* re-enable the MMU */
+ write_aux_reg(ARC_REG_PID, MMU_ENABLE | read_aux_reg(ARC_REG_PID));
+
+ /* loop thru all sets of TLB */
+ for (set = 0; set < mmu->sets; set++) {
+
+ /* read out all the ways of current set */
+ for (way = 0, is_valid = 0; way < mmu->ways; way++) {
+ write_aux_reg(ARC_REG_TLBINDEX,
+ SET_WAY_TO_IDX(mmu, set, way));
+ write_aux_reg(ARC_REG_TLBCOMMAND, TLBRead);
+ pd0[way] = read_aux_reg(ARC_REG_TLBPD0);
+ pd1[way] = read_aux_reg(ARC_REG_TLBPD1);
+ is_valid |= pd0[way] & _PAGE_PRESENT;
+ }
+
+ /* If all the WAYS in SET are empty, skip to next SET */
+ if (!is_valid)
+ continue;
+
+ /* Scan the set for duplicate ways: needs a nested loop */
+ for (way = 0; way < mmu->ways; way++) {
+ if (!pd0[way])
+ continue;
+
+ for (n = way + 1; n < mmu->ways; n++) {
+ if ((pd0[way] & PAGE_MASK) ==
+ (pd0[n] & PAGE_MASK)) {
+
+ if (dup_pd_verbose) {
+ pr_info("Duplicate PD's @"
+ "[%d:%d]/[%d:%d]\n",
+ set, way, set, n);
+ pr_info("TLBPD0[%u]: %08x\n",
+ way, pd0[way]);
+ }
+
+ /*
+ * clear entry @way and not @n. This is
+ * critical to our optimised loop
+ */
+ pd0[way] = pd1[way] = 0;
+ write_aux_reg(ARC_REG_TLBINDEX,
+ SET_WAY_TO_IDX(mmu, set, way));
+ __tlb_entry_erase();
+ }
+ }
+ }
+ }
+
+ local_irq_restore(flags);
+}
+
+/***********************************************************************
+ * Diagnostic Routines
+ * -Called from Low Level TLB Hanlders if things don;t look good
+ **********************************************************************/
+
+#ifdef CONFIG_ARC_DBG_TLB_PARANOIA
+
+/*
+ * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS
+ * don't match
+ */
+void print_asid_mismatch(int is_fast_path)
+{
+ int pid_sw, pid_hw;
+ pid_sw = current->active_mm->context.asid;
+ pid_hw = read_aux_reg(ARC_REG_PID) & 0xff;
+
+ pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n",
+ is_fast_path ? "Fast" : "Slow", pid_sw, pid_hw);
+
+ __asm__ __volatile__("flag 1");
+}
+
+void tlb_paranoid_check(unsigned int pid_sw, unsigned long addr)
+{
+ unsigned int pid_hw;
+
+ pid_hw = read_aux_reg(ARC_REG_PID) & 0xff;
+
+ if (addr < 0x70000000 && ((pid_hw != pid_sw) || (pid_sw == NO_ASID)))
+ print_asid_mismatch(0);
+}
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-26 17:59:47 +0000