blob: f90ac35f05f3e5b78fe5365bcedba8cf59acd46f [file] [log] [blame]
/*
* Nios2 TLB handling
*
* Copyright (C) 2009, Wind River Systems Inc
* Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
*
* 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.
*/
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>
#include <asm/cpuinfo.h>
#define TLB_INDEX_MASK \
((((1UL << (cpuinfo.tlb_ptr_sz - cpuinfo.tlb_num_ways_log2))) - 1) \
<< PAGE_SHIFT)
static void get_misc_and_pid(unsigned long *misc, unsigned long *pid)
{
*misc = RDCTL(CTL_TLBMISC);
*misc &= (TLBMISC_PID | TLBMISC_WAY);
*pid = *misc & TLBMISC_PID;
}
/*
* This provides a PTEADDR value for addr that will cause a TLB miss
* (fast TLB miss). TLB invalidation replaces entries with this value.
*/
static unsigned long pteaddr_invalid(unsigned long addr)
{
return ((addr | 0xC0000000UL) >> PAGE_SHIFT) << 2;
}
/*
* This one is only used for pages with the global bit set so we don't care
* much about the ASID.
*/
static void replace_tlb_one_pid(unsigned long addr, unsigned long mmu_pid, unsigned long tlbacc)
{
unsigned int way;
unsigned long org_misc, pid_misc;
/* remember pid/way until we return. */
get_misc_and_pid(&org_misc, &pid_misc);
WRCTL(CTL_PTEADDR, (addr >> PAGE_SHIFT) << 2);
for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
unsigned long pteaddr;
unsigned long tlbmisc;
unsigned long pid;
tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
pteaddr = RDCTL(CTL_PTEADDR);
if (((pteaddr >> 2) & 0xfffff) != (addr >> PAGE_SHIFT))
continue;
tlbmisc = RDCTL(CTL_TLBMISC);
pid = (tlbmisc >> TLBMISC_PID_SHIFT) & TLBMISC_PID_MASK;
if (pid != mmu_pid)
continue;
tlbmisc = (mmu_pid << TLBMISC_PID_SHIFT) | TLBMISC_WE |
(way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
if (tlbacc == 0)
WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
WRCTL(CTL_TLBACC, tlbacc);
/*
* There should be only a single entry that maps a
* particular {address,pid} so break after a match.
*/
break;
}
WRCTL(CTL_TLBMISC, org_misc);
}
static void flush_tlb_one_pid(unsigned long addr, unsigned long mmu_pid)
{
pr_debug("Flush tlb-entry for vaddr=%#lx\n", addr);
replace_tlb_one_pid(addr, mmu_pid, 0);
}
static void reload_tlb_one_pid(unsigned long addr, unsigned long mmu_pid, pte_t pte)
{
pr_debug("Reload tlb-entry for vaddr=%#lx\n", addr);
replace_tlb_one_pid(addr, mmu_pid, pte_val(pte));
}
void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
unsigned long mmu_pid = get_pid_from_context(&vma->vm_mm->context);
while (start < end) {
flush_tlb_one_pid(start, mmu_pid);
start += PAGE_SIZE;
}
}
void reload_tlb_page(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
{
unsigned long mmu_pid = get_pid_from_context(&vma->vm_mm->context);
reload_tlb_one_pid(addr, mmu_pid, pte);
}
/*
* This one is only used for pages with the global bit set so we don't care
* much about the ASID.
*/
static void flush_tlb_one(unsigned long addr)
{
unsigned int way;
unsigned long org_misc, pid_misc;
pr_debug("Flush tlb-entry for vaddr=%#lx\n", addr);
/* remember pid/way until we return. */
get_misc_and_pid(&org_misc, &pid_misc);
WRCTL(CTL_PTEADDR, (addr >> PAGE_SHIFT) << 2);
for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
unsigned long pteaddr;
unsigned long tlbmisc;
tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
pteaddr = RDCTL(CTL_PTEADDR);
if (((pteaddr >> 2) & 0xfffff) != (addr >> PAGE_SHIFT))
continue;
pr_debug("Flush entry by writing way=%dl pid=%ld\n",
way, (pid_misc >> TLBMISC_PID_SHIFT));
tlbmisc = TLBMISC_WE | (way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
WRCTL(CTL_TLBACC, 0);
}
WRCTL(CTL_TLBMISC, org_misc);
}
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
while (start < end) {
flush_tlb_one(start);
start += PAGE_SIZE;
}
}
void dump_tlb_line(unsigned long line)
{
unsigned int way;
unsigned long org_misc;
pr_debug("dump tlb-entries for line=%#lx (addr %08lx)\n", line,
line << (PAGE_SHIFT + cpuinfo.tlb_num_ways_log2));
/* remember pid/way until we return */
org_misc = (RDCTL(CTL_TLBMISC) & (TLBMISC_PID | TLBMISC_WAY));
WRCTL(CTL_PTEADDR, line << 2);
for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
unsigned long pteaddr;
unsigned long tlbmisc;
unsigned long tlbacc;
WRCTL(CTL_TLBMISC, TLBMISC_RD | (way << TLBMISC_WAY_SHIFT));
pteaddr = RDCTL(CTL_PTEADDR);
tlbmisc = RDCTL(CTL_TLBMISC);
tlbacc = RDCTL(CTL_TLBACC);
if ((tlbacc << PAGE_SHIFT) != 0) {
pr_debug("-- way:%02x vpn:0x%08lx phys:0x%08lx pid:0x%02lx flags:%c%c%c%c%c\n",
way,
(pteaddr << (PAGE_SHIFT-2)),
(tlbacc << PAGE_SHIFT),
((tlbmisc >> TLBMISC_PID_SHIFT) &
TLBMISC_PID_MASK),
(tlbacc & _PAGE_READ ? 'r' : '-'),
(tlbacc & _PAGE_WRITE ? 'w' : '-'),
(tlbacc & _PAGE_EXEC ? 'x' : '-'),
(tlbacc & _PAGE_GLOBAL ? 'g' : '-'),
(tlbacc & _PAGE_CACHED ? 'c' : '-'));
}
}
WRCTL(CTL_TLBMISC, org_misc);
}
void dump_tlb(void)
{
unsigned int i;
for (i = 0; i < cpuinfo.tlb_num_lines; i++)
dump_tlb_line(i);
}
void flush_tlb_pid(unsigned long mmu_pid)
{
unsigned long addr = 0;
unsigned int line;
unsigned int way;
unsigned long org_misc, pid_misc;
/* remember pid/way until we return */
get_misc_and_pid(&org_misc, &pid_misc);
for (line = 0; line < cpuinfo.tlb_num_lines; line++) {
WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
unsigned long tlbmisc;
unsigned long pid;
tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
tlbmisc = RDCTL(CTL_TLBMISC);
pid = (tlbmisc >> TLBMISC_PID_SHIFT) & TLBMISC_PID_MASK;
if (pid != mmu_pid)
continue;
tlbmisc = TLBMISC_WE | (way << TLBMISC_WAY_SHIFT);
WRCTL(CTL_TLBMISC, tlbmisc);
WRCTL(CTL_TLBACC, 0);
}
addr += PAGE_SIZE;
}
WRCTL(CTL_TLBMISC, org_misc);
}
/*
* All entries common to a mm share an asid. To effectively flush these
* entries, we just bump the asid.
*/
void flush_tlb_mm(struct mm_struct *mm)
{
if (current->mm == mm) {
unsigned long mmu_pid = get_pid_from_context(&mm->context);
flush_tlb_pid(mmu_pid);
} else {
memset(&mm->context, 0, sizeof(mm_context_t));
}
}
void flush_tlb_all(void)
{
unsigned long addr = 0;
unsigned int line;
unsigned int way;
unsigned long org_misc, pid_misc;
/* remember pid/way until we return */
get_misc_and_pid(&org_misc, &pid_misc);
/* Start at way 0, way is auto-incremented after each TLBACC write */
WRCTL(CTL_TLBMISC, TLBMISC_WE);
/* Map each TLB entry to physcal address 0 with no-access and a
bad ptbase */
for (line = 0; line < cpuinfo.tlb_num_lines; line++) {
WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
for (way = 0; way < cpuinfo.tlb_num_ways; way++)
WRCTL(CTL_TLBACC, 0);
addr += PAGE_SIZE;
}
/* restore pid/way */
WRCTL(CTL_TLBMISC, org_misc);
}
void set_mmu_pid(unsigned long pid)
{
unsigned long tlbmisc;
tlbmisc = RDCTL(CTL_TLBMISC);
tlbmisc = (tlbmisc & TLBMISC_WAY);
tlbmisc |= (pid & TLBMISC_PID_MASK) << TLBMISC_PID_SHIFT;
WRCTL(CTL_TLBMISC, tlbmisc);
}