kernel-ark/arch/avr32/mm/tlb.c
Arjan van de Ven 5dfe4c964a [PATCH] mark struct file_operations const 2
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

[akpm@osdl.org: sparc64 fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:44 -08:00

381 lines
8.2 KiB
C

/*
* 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>
#define _TLBEHI_I 0x100
void show_dtlb_entry(unsigned int index)
{
unsigned int 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 = mmucr_save & 0x13;
mmucr |= index << 14;
sysreg_write(MMUCR, mmucr);
asm volatile("tlbr" : : : "memory");
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,
(tlbehi & 0x200)?'1':'0',
(tlbelo & 0x100)?'1':'0',
(tlbehi & 0xff),
(tlbehi >> 12), (tlbelo >> 12),
(tlbelo >> 4) & 7, (tlbelo >> 2) & 3,
(tlbelo & 0x200)?'1':'0',
(tlbelo & 0x080)?'1':'0',
(tlbelo & 0x001)?'1':'0',
(tlbelo & 0x002)?'1':'0');
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 < 32; i++)
show_dtlb_entry(i);
}
static unsigned long last_mmucr;
static inline void set_replacement_pointer(unsigned shift)
{
unsigned long mmucr, mmucr_save;
mmucr = mmucr_save = sysreg_read(MMUCR);
/* Does this mapping already exist? */
__asm__ __volatile__(
" tlbs\n"
" mfsr %0, %1"
: "=r"(mmucr)
: "i"(SYSREG_MMUCR));
if (mmucr & SYSREG_BIT(MMUCR_N)) {
/* Not found -- pick a not-recently-accessed entry */
unsigned long rp;
unsigned long tlbar = sysreg_read(TLBARLO);
rp = 32 - fls(tlbar);
if (rp == 32) {
rp = 0;
sysreg_write(TLBARLO, -1L);
}
mmucr &= 0x13;
mmucr |= (rp << shift);
sysreg_write(MMUCR, mmucr);
}
last_mmucr = mmucr;
}
static void update_dtlb(unsigned long address, pte_t pte, unsigned long asid)
{
unsigned long vpn;
vpn = (address & MMU_VPN_MASK) | _TLBEHI_VALID | asid;
sysreg_write(TLBEHI, vpn);
cpu_sync_pipeline();
set_replacement_pointer(14);
sysreg_write(TLBELO, pte_val(pte) & _PAGE_FLAGS_HARDWARE_MASK);
/* Let's go */
asm volatile("nop\n\ttlbw" : : : "memory");
cpu_sync_pipeline();
}
void update_mmu_cache(struct vm_area_struct *vma,
unsigned long address, pte_t pte)
{
unsigned long flags;
/* ptrace may call this routine */
if (vma && current->active_mm != vma->vm_mm)
return;
local_irq_save(flags);
update_dtlb(address, pte, get_asid());
local_irq_restore(flags);
}
void __flush_tlb_page(unsigned long asid, unsigned long page)
{
unsigned long mmucr, tlbehi;
page |= asid;
sysreg_write(TLBEHI, page);
cpu_sync_pipeline();
asm volatile("tlbs");
mmucr = sysreg_read(MMUCR);
if (!(mmucr & SYSREG_BIT(MMUCR_N))) {
unsigned long tlbarlo;
unsigned long entry;
/* Clear the "valid" bit */
tlbehi = sysreg_read(TLBEHI);
tlbehi &= ~_TLBEHI_VALID;
sysreg_write(TLBEHI, tlbehi);
cpu_sync_pipeline();
/* mark the entry as "not accessed" */
entry = (mmucr >> 14) & 0x3f;
tlbarlo = sysreg_read(TLBARLO);
tlbarlo |= (0x80000000 >> entry);
sysreg_write(TLBARLO, tlbarlo);
/* update the entry with valid bit clear */
asm volatile("tlbw");
cpu_sync_pipeline();
}
}
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 = mm->context & MMU_CONTEXT_ASID_MASK;
unsigned long 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);
}
}
/*
* TODO: If this is only called for addresses > TASK_SIZE, we can probably
* skip the ASID stuff and just use the Global bit...
*/
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
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 */
flush_tlb_all();
} else {
unsigned long asid = init_mm.context & MMU_CONTEXT_ASID_MASK;
unsigned long saved_asid = get_asid();
start &= PAGE_MASK;
end += (PAGE_SIZE - 1);
end &= PAGE_MASK;
set_asid(asid);
while (start < end) {
__flush_tlb_page(asid, start);
start += PAGE_SIZE;
}
set_asid(saved_asid);
}
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 >= 32)
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 >= 31)
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 >= 32);
local_irq_save(flags);
mmucr_save = sysreg_read(MMUCR);
tlbehi_save = sysreg_read(TLBEHI);
mmucr = mmucr_save & 0x13;
mmucr |= *index << 14;
sysreg_write(MMUCR, mmucr);
asm volatile("tlbr" : : : "memory");
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,
(tlbehi & 0x200)?'1':'0',
(tlbelo & 0x100)?'1':'0',
(tlbehi & 0xff),
(tlbehi >> 12), (tlbelo >> 12),
(tlbelo >> 4) & 7, (tlbelo >> 2) & 3,
(tlbelo & 0x200)?'1':'0',
(tlbelo & 0x080)?'1':'0',
(tlbelo & 0x001)?'1':'0',
(tlbelo & 0x002)?'1':'0');
return 0;
}
static 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)
{
struct proc_dir_entry *entry;
entry = create_proc_entry("tlb", 0, NULL);
if (entry)
entry->proc_fops = &proc_tlb_operations;
return 0;
}
late_initcall(proctlb_init);
#endif /* CONFIG_PROC_FS */