Initial import

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 */