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-rw-r--r--arch/avr32/mm/tlb.c375
1 files changed, 375 insertions, 0 deletions
diff --git a/arch/avr32/mm/tlb.c b/arch/avr32/mm/tlb.c
new file mode 100644
index 000000000..0da23109f
--- /dev/null
+++ b/arch/avr32/mm/tlb.c
@@ -0,0 +1,375 @@
+/*
+ * AVR32 TLB operations
+ *
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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/mm.h>
+
+#include <asm/mmu_context.h>
+
+/* TODO: Get the correct number from the CONFIG1 system register */
+#define NR_TLB_ENTRIES 32
+
+static void show_dtlb_entry(unsigned int index)
+{
+ u32 tlbehi, tlbehi_save, tlbelo, mmucr, mmucr_save;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ mmucr_save = sysreg_read(MMUCR);
+ tlbehi_save = sysreg_read(TLBEHI);
+ mmucr = SYSREG_BFINS(DRP, index, mmucr_save);
+ sysreg_write(MMUCR, mmucr);
+
+ __builtin_tlbr();
+ cpu_sync_pipeline();
+
+ tlbehi = sysreg_read(TLBEHI);
+ tlbelo = sysreg_read(TLBELO);
+
+ printk("%2u: %c %c %02x %05x %05x %o %o %c %c %c %c\n",
+ index,
+ SYSREG_BFEXT(TLBEHI_V, tlbehi) ? '1' : '0',
+ SYSREG_BFEXT(G, tlbelo) ? '1' : '0',
+ SYSREG_BFEXT(ASID, tlbehi),
+ SYSREG_BFEXT(VPN, tlbehi) >> 2,
+ SYSREG_BFEXT(PFN, tlbelo) >> 2,
+ SYSREG_BFEXT(AP, tlbelo),
+ SYSREG_BFEXT(SZ, tlbelo),
+ SYSREG_BFEXT(TLBELO_C, tlbelo) ? 'C' : ' ',
+ SYSREG_BFEXT(B, tlbelo) ? 'B' : ' ',
+ SYSREG_BFEXT(W, tlbelo) ? 'W' : ' ',
+ SYSREG_BFEXT(TLBELO_D, tlbelo) ? 'D' : ' ');
+
+ sysreg_write(MMUCR, mmucr_save);
+ sysreg_write(TLBEHI, tlbehi_save);
+ cpu_sync_pipeline();
+ local_irq_restore(flags);
+}
+
+void dump_dtlb(void)
+{
+ unsigned int i;
+
+ printk("ID V G ASID VPN PFN AP SZ C B W D\n");
+ for (i = 0; i < NR_TLB_ENTRIES; i++)
+ show_dtlb_entry(i);
+}
+
+static void update_dtlb(unsigned long address, pte_t pte)
+{
+ u32 tlbehi;
+ u32 mmucr;
+
+ /*
+ * We're not changing the ASID here, so no need to flush the
+ * pipeline.
+ */
+ tlbehi = sysreg_read(TLBEHI);
+ tlbehi = SYSREG_BF(ASID, SYSREG_BFEXT(ASID, tlbehi));
+ tlbehi |= address & MMU_VPN_MASK;
+ tlbehi |= SYSREG_BIT(TLBEHI_V);
+ sysreg_write(TLBEHI, tlbehi);
+
+ /* Does this mapping already exist? */
+ __builtin_tlbs();
+ mmucr = sysreg_read(MMUCR);
+
+ if (mmucr & SYSREG_BIT(MMUCR_N)) {
+ /* Not found -- pick a not-recently-accessed entry */
+ unsigned int rp;
+ u32 tlbar = sysreg_read(TLBARLO);
+
+ rp = 32 - fls(tlbar);
+ if (rp == 32) {
+ rp = 0;
+ sysreg_write(TLBARLO, -1L);
+ }
+
+ mmucr = SYSREG_BFINS(DRP, rp, mmucr);
+ sysreg_write(MMUCR, mmucr);
+ }
+
+ sysreg_write(TLBELO, pte_val(pte) & _PAGE_FLAGS_HARDWARE_MASK);
+
+ /* Let's go */
+ __builtin_tlbw();
+}
+
+void update_mmu_cache(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep)
+{
+ unsigned long flags;
+
+ /* ptrace may call this routine */
+ if (vma && current->active_mm != vma->vm_mm)
+ return;
+
+ local_irq_save(flags);
+ update_dtlb(address, *ptep);
+ local_irq_restore(flags);
+}
+
+static void __flush_tlb_page(unsigned long asid, unsigned long page)
+{
+ u32 mmucr, tlbehi;
+
+ /*
+ * Caller is responsible for masking out non-PFN bits in page
+ * and changing the current ASID if necessary. This means that
+ * we don't need to flush the pipeline after writing TLBEHI.
+ */
+ tlbehi = page | asid;
+ sysreg_write(TLBEHI, tlbehi);
+
+ __builtin_tlbs();
+ mmucr = sysreg_read(MMUCR);
+
+ if (!(mmucr & SYSREG_BIT(MMUCR_N))) {
+ unsigned int entry;
+ u32 tlbarlo;
+
+ /* Clear the "valid" bit */
+ sysreg_write(TLBEHI, tlbehi);
+
+ /* mark the entry as "not accessed" */
+ entry = SYSREG_BFEXT(DRP, mmucr);
+ tlbarlo = sysreg_read(TLBARLO);
+ tlbarlo |= (0x80000000UL >> entry);
+ sysreg_write(TLBARLO, tlbarlo);
+
+ /* update the entry with valid bit clear */
+ __builtin_tlbw();
+ }
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+ if (vma->vm_mm && vma->vm_mm->context != NO_CONTEXT) {
+ unsigned long flags, asid;
+ unsigned long saved_asid = MMU_NO_ASID;
+
+ asid = vma->vm_mm->context & MMU_CONTEXT_ASID_MASK;
+ page &= PAGE_MASK;
+
+ local_irq_save(flags);
+ if (vma->vm_mm != current->mm) {
+ saved_asid = get_asid();
+ set_asid(asid);
+ }
+
+ __flush_tlb_page(asid, page);
+
+ if (saved_asid != MMU_NO_ASID)
+ set_asid(saved_asid);
+ local_irq_restore(flags);
+ }
+}
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ struct mm_struct *mm = vma->vm_mm;
+
+ if (mm->context != NO_CONTEXT) {
+ unsigned long flags;
+ int size;
+
+ local_irq_save(flags);
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+
+ if (size > (MMU_DTLB_ENTRIES / 4)) { /* Too many entries to flush */
+ mm->context = NO_CONTEXT;
+ if (mm == current->mm)
+ activate_context(mm);
+ } else {
+ unsigned long asid;
+ unsigned long saved_asid;
+
+ asid = mm->context & MMU_CONTEXT_ASID_MASK;
+ saved_asid = MMU_NO_ASID;
+
+ start &= PAGE_MASK;
+ end += (PAGE_SIZE - 1);
+ end &= PAGE_MASK;
+
+ if (mm != current->mm) {
+ saved_asid = get_asid();
+ set_asid(asid);
+ }
+
+ while (start < end) {
+ __flush_tlb_page(asid, start);
+ start += PAGE_SIZE;
+ }
+ if (saved_asid != MMU_NO_ASID)
+ set_asid(saved_asid);
+ }
+ local_irq_restore(flags);
+ }
+}
+
+/*
+ * This function depends on the pages to be flushed having the G
+ * (global) bit set in their pte. This is true for all
+ * PAGE_KERNEL(_RO) pages.
+ */
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ unsigned long flags;
+ int size;
+
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+ if (size > (MMU_DTLB_ENTRIES / 4)) { /* Too many entries to flush */
+ flush_tlb_all();
+ } else {
+ unsigned long asid;
+
+ local_irq_save(flags);
+ asid = get_asid();
+
+ start &= PAGE_MASK;
+ end += (PAGE_SIZE - 1);
+ end &= PAGE_MASK;
+
+ while (start < end) {
+ __flush_tlb_page(asid, start);
+ start += PAGE_SIZE;
+ }
+ local_irq_restore(flags);
+ }
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+ /* Invalidate all TLB entries of this process by getting a new ASID */
+ if (mm->context != NO_CONTEXT) {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ mm->context = NO_CONTEXT;
+ if (mm == current->mm)
+ activate_context(mm);
+ local_irq_restore(flags);
+ }
+}
+
+void flush_tlb_all(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ sysreg_write(MMUCR, sysreg_read(MMUCR) | SYSREG_BIT(MMUCR_I));
+ local_irq_restore(flags);
+}
+
+#ifdef CONFIG_PROC_FS
+
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+
+static void *tlb_start(struct seq_file *tlb, loff_t *pos)
+{
+ static unsigned long tlb_index;
+
+ if (*pos >= NR_TLB_ENTRIES)
+ return NULL;
+
+ tlb_index = 0;
+ return &tlb_index;
+}
+
+static void *tlb_next(struct seq_file *tlb, void *v, loff_t *pos)
+{
+ unsigned long *index = v;
+
+ if (*index >= NR_TLB_ENTRIES - 1)
+ return NULL;
+
+ ++*pos;
+ ++*index;
+ return index;
+}
+
+static void tlb_stop(struct seq_file *tlb, void *v)
+{
+
+}
+
+static int tlb_show(struct seq_file *tlb, void *v)
+{
+ unsigned int tlbehi, tlbehi_save, tlbelo, mmucr, mmucr_save;
+ unsigned long flags;
+ unsigned long *index = v;
+
+ if (*index == 0)
+ seq_puts(tlb, "ID V G ASID VPN PFN AP SZ C B W D\n");
+
+ BUG_ON(*index >= NR_TLB_ENTRIES);
+
+ local_irq_save(flags);
+ mmucr_save = sysreg_read(MMUCR);
+ tlbehi_save = sysreg_read(TLBEHI);
+ mmucr = SYSREG_BFINS(DRP, *index, mmucr_save);
+ sysreg_write(MMUCR, mmucr);
+
+ /* TLBR might change the ASID */
+ __builtin_tlbr();
+ cpu_sync_pipeline();
+
+ tlbehi = sysreg_read(TLBEHI);
+ tlbelo = sysreg_read(TLBELO);
+
+ sysreg_write(MMUCR, mmucr_save);
+ sysreg_write(TLBEHI, tlbehi_save);
+ cpu_sync_pipeline();
+ local_irq_restore(flags);
+
+ seq_printf(tlb, "%2lu: %c %c %02x %05x %05x %o %o %c %c %c %c\n",
+ *index,
+ SYSREG_BFEXT(TLBEHI_V, tlbehi) ? '1' : '0',
+ SYSREG_BFEXT(G, tlbelo) ? '1' : '0',
+ SYSREG_BFEXT(ASID, tlbehi),
+ SYSREG_BFEXT(VPN, tlbehi) >> 2,
+ SYSREG_BFEXT(PFN, tlbelo) >> 2,
+ SYSREG_BFEXT(AP, tlbelo),
+ SYSREG_BFEXT(SZ, tlbelo),
+ SYSREG_BFEXT(TLBELO_C, tlbelo) ? '1' : '0',
+ SYSREG_BFEXT(B, tlbelo) ? '1' : '0',
+ SYSREG_BFEXT(W, tlbelo) ? '1' : '0',
+ SYSREG_BFEXT(TLBELO_D, tlbelo) ? '1' : '0');
+
+ return 0;
+}
+
+static const struct seq_operations tlb_ops = {
+ .start = tlb_start,
+ .next = tlb_next,
+ .stop = tlb_stop,
+ .show = tlb_show,
+};
+
+static int tlb_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &tlb_ops);
+}
+
+static const struct file_operations proc_tlb_operations = {
+ .open = tlb_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init proctlb_init(void)
+{
+ proc_create("tlb", 0, NULL, &proc_tlb_operations);
+ return 0;
+}
+late_initcall(proctlb_init);
+#endif /* CONFIG_PROC_FS */
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