/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1997, 1998, 1999 Ralf Baechle (ralf@gnu.org)
* Copyright (C) 1999 Silicon Graphics, Inc.
* Copyright (C) 2000 Kanoj Sarcar (kanoj@sgi.com)
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
extern void build_tlb_refill_handler(void);
#define NTLB_ENTRIES 64
#define NTLB_ENTRIES_HALF 32
void local_flush_tlb_all(void)
{
unsigned long flags;
unsigned long old_ctx;
unsigned long entry;
local_irq_save(flags);
/* Save old context and create impossible VPN2 value */
old_ctx = read_c0_entryhi() & ASID_MASK;
write_c0_entryhi(CKSEG0);
write_c0_entrylo0(0);
write_c0_entrylo1(0);
entry = read_c0_wired();
/* Blast 'em all away. */
while (entry < NTLB_ENTRIES) {
write_c0_index(entry);
tlb_write_indexed();
entry++;
}
write_c0_entryhi(old_ctx);
local_irq_restore(flags);
}
void local_flush_tlb_mm(struct mm_struct *mm)
{
int cpu = smp_processor_id();
if (cpu_context(cpu, mm) != 0) {
drop_mmu_context(mm,cpu);
}
}
void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
int cpu = smp_processor_id();
if (cpu_context(cpu, mm) != 0) {
unsigned long flags;
int size;
local_irq_save(flags);
size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
size = (size + 1) >> 1;
if (size <= NTLB_ENTRIES_HALF) {
int oldpid = (read_c0_entryhi() & ASID_MASK);
int newpid = (cpu_context(smp_processor_id(), mm)
& ASID_MASK);
start &= (PAGE_MASK << 1);
end += ((PAGE_SIZE << 1) - 1);
end &= (PAGE_MASK << 1);
while(start < end) {
int idx;
write_c0_entryhi(start | newpid);
start += (PAGE_SIZE << 1);
tlb_probe();
idx = read_c0_index();
write_c0_entrylo0(0);
write_c0_entrylo1(0);
write_c0_entryhi(CKSEG0);
if(idx < 0)
continue;
tlb_write_indexed();
}
write_c0_entryhi(oldpid);
} else {
drop_mmu_context(mm, cpu);
}
local_irq_restore(flags);
}
}
void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
unsigned long flags;
int size;
size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
size = (size + 1) >> 1;
local_irq_save(flags);
if (size <= NTLB_ENTRIES_HALF) {
int pid = read_c0_entryhi();
start &= (PAGE_MASK << 1);
end += ((PAGE_SIZE << 1) - 1);
end &= (PAGE_MASK << 1);
while (start < end) {
int idx;
write_c0_entryhi(start);
start += (PAGE_SIZE << 1);
tlb_probe();
idx = read_c0_index();
write_c0_entrylo0(0);
write_c0_entrylo1(0);
write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT+1)));
if (idx < 0)
continue;
tlb_write_indexed();
}
write_c0_entryhi(pid);
} else {
local_flush_tlb_all();
}
local_irq_restore(flags);
}
void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
if (cpu_context(smp_processor_id(), vma->vm_mm) != 0) {
unsigned long flags;
int oldpid, newpid, idx;
newpid = (cpu_context(smp_processor_id(), vma->vm_mm) &
ASID_MASK);
page &= (PAGE_MASK << 1);
local_irq_save(flags);
oldpid = (read_c0_entryhi() & ASID_MASK);
write_c0_entryhi(page | newpid);
tlb_probe();
idx = read_c0_index();
write_c0_entrylo0(0);
write_c0_entrylo1(0);
write_c0_entryhi(CKSEG0);
if (idx < 0)
goto finish;
tlb_write_indexed();
finish:
write_c0_entryhi(oldpid);
local_irq_restore(flags);
}
}
/*
* This one is only used for pages with the global bit set so we don't care
* much about the ASID.
*/
void local_flush_tlb_one(unsigned long page)
{
unsigned long flags;
int oldpid, idx;
local_irq_save(flags);
page &= (PAGE_MASK << 1);
oldpid = read_c0_entryhi() & 0xff;
write_c0_entryhi(page);
tlb_probe();
idx = read_c0_index();
write_c0_entrylo0(0);
write_c0_entrylo1(0);
if (idx >= 0) {
/* Make sure all entries differ. */
write_c0_entryhi(CKSEG0+(idx<<(PAGE_SHIFT+1)));
tlb_write_indexed();
}
write_c0_entryhi(oldpid);
local_irq_restore(flags);
}
/* XXX Simplify this. On the R10000 writing a TLB entry for an virtual
address that already exists will overwrite the old entry and not result
in TLB malfunction or TLB shutdown. */
void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte)
{
unsigned long flags;
pgd_t *pgdp;
pmd_t *pmdp;
pte_t *ptep;
int idx, pid;
/*
* Handle debugger faulting in for debugee.
*/
if (current->active_mm != vma->vm_mm)
return;
pid = read_c0_entryhi() & ASID_MASK;
if ((pid != (cpu_context(smp_processor_id(), vma->vm_mm) & ASID_MASK))
|| (cpu_context(smp_processor_id(), vma->vm_mm) == 0)) {
printk(KERN_WARNING
"%s: Wheee, bogus tlbpid mmpid=%d tlbpid=%d\n",
__FUNCTION__, (int) (cpu_context(smp_processor_id(),
vma->vm_mm) & ASID_MASK), pid);
}
local_irq_save(flags);
address &= (PAGE_MASK << 1);
write_c0_entryhi(address | (pid));
pgdp = pgd_offset(vma->vm_mm, address);
tlb_probe();
pmdp = pmd_offset(pgdp, address);
idx = read_c0_index();
ptep = pte_offset_map(pmdp, address);
write_c0_entrylo0(pte_val(*ptep++) >> 6);
write_c0_entrylo1(pte_val(*ptep) >> 6);
write_c0_entryhi(address | pid);
if (idx < 0) {
tlb_write_random();
} else {
tlb_write_indexed();
}
write_c0_entryhi(pid);
local_irq_restore(flags);
}
void __init tlb_init(void)
{
/*
* You should never change this register:
* - On R4600 1.7 the tlbp never hits for pages smaller than
* the value in the c0_pagemask register.
* - The entire mm handling assumes the c0_pagemask register to
* be set for 4kb pages.
*/
write_c0_pagemask(PM_4K);
write_c0_wired(0);
write_c0_framemask(0);
/* From this point on the ARC firmware is dead. */
local_flush_tlb_all();
/* Did I tell you that ARC SUCKS? */
build_tlb_refill_handler();
}
