Viewing file:  tlb.c (4.59 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* TLB support routines.
*
* Copyright (C) 1998-2001 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*
* 08/02/00 A. Mallick <asit.k.mallick@intel.com>
* Modified RID allocation for SMP
* Goutham Rao <goutham.rao@intel.com>
* IPI based ptc implementation and A-step IPI implementation.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/mm.h>
#include <asm/mmu_context.h>
#include <asm/pgalloc.h>
#include <asm/pal.h>
#include <asm/delay.h>
#define SUPPORTED_PGBITS ( \
1 << _PAGE_SIZE_256M | \
1 << _PAGE_SIZE_64M | \
1 << _PAGE_SIZE_16M | \
1 << _PAGE_SIZE_4M | \
1 << _PAGE_SIZE_1M | \
1 << _PAGE_SIZE_256K | \
1 << _PAGE_SIZE_64K | \
1 << _PAGE_SIZE_16K | \
1 << _PAGE_SIZE_8K | \
1 << _PAGE_SIZE_4K )
struct ia64_ctx ia64_ctx = {
lock: SPIN_LOCK_UNLOCKED,
next: 1,
limit: (1 << 15) - 1, /* start out with the safe (architected) limit */
max_ctx: ~0U
};
/*
* Acquire the ia64_ctx.lock before calling this function!
*/
void
wrap_mmu_context (struct mm_struct *mm)
{
unsigned long tsk_context, max_ctx = ia64_ctx.max_ctx;
struct task_struct *tsk;
if (ia64_ctx.next > max_ctx)
ia64_ctx.next = 300; /* skip daemons */
ia64_ctx.limit = max_ctx + 1;
/*
* Scan all the task's mm->context and set proper safe range
*/
read_lock(&tasklist_lock);
repeat:
for_each_task(tsk) {
if (!tsk->mm)
continue;
tsk_context = tsk->mm->context;
if (tsk_context == ia64_ctx.next) {
if (++ia64_ctx.next >= ia64_ctx.limit) {
/* empty range: reset the range limit and start over */
if (ia64_ctx.next > max_ctx)
ia64_ctx.next = 300;
ia64_ctx.limit = max_ctx + 1;
goto repeat;
}
}
if ((tsk_context > ia64_ctx.next) && (tsk_context < ia64_ctx.limit))
ia64_ctx.limit = tsk_context;
}
read_unlock(&tasklist_lock);
flush_tlb_all();
}
static inline void
ia64_global_tlb_purge (unsigned long start, unsigned long end, unsigned long nbits)
{
static spinlock_t ptcg_lock = SPIN_LOCK_UNLOCKED;
/* HW requires global serialization of ptc.ga. */
spin_lock(&ptcg_lock);
{
do {
/*
* Flush ALAT entries also.
*/
asm volatile ("ptc.ga %0,%1;;srlz.i;;" :: "r"(start), "r"(nbits<<2)
: "memory");
start += (1UL << nbits);
} while (start < end);
}
spin_unlock(&ptcg_lock);
}
void
__flush_tlb_all (void)
{
unsigned long i, j, flags, count0, count1, stride0, stride1, addr;
addr = local_cpu_data->ptce_base;
count0 = local_cpu_data->ptce_count[0];
count1 = local_cpu_data->ptce_count[1];
stride0 = local_cpu_data->ptce_stride[0];
stride1 = local_cpu_data->ptce_stride[1];
local_irq_save(flags);
for (i = 0; i < count0; ++i) {
for (j = 0; j < count1; ++j) {
asm volatile ("ptc.e %0" :: "r"(addr));
addr += stride1;
}
addr += stride0;
}
local_irq_restore(flags);
ia64_insn_group_barrier();
ia64_srlz_i(); /* srlz.i implies srlz.d */
ia64_insn_group_barrier();
}
void
flush_tlb_range (struct mm_struct *mm, unsigned long start, unsigned long end)
{
unsigned long size = end - start;
unsigned long nbits;
if (mm != current->active_mm) {
/* this does happen, but perhaps it's not worth optimizing for? */
#ifdef CONFIG_SMP
flush_tlb_all();
#else
mm->context = 0;
#endif
return;
}
nbits = ia64_fls(size + 0xfff);
if (((1UL << nbits) & SUPPORTED_PGBITS) == 0) {
if (nbits > _PAGE_SIZE_256M)
nbits = _PAGE_SIZE_256M;
else
/*
* Some page sizes are not implemented in the
* IA-64 arch, so if we get asked to clear an
* unsupported page size, round up to the
* nearest page size. Note that we depend on
* the fact that if page size N is not
* implemented, 2*N _is_ implemented.
*/
++nbits;
if (((1UL << nbits) & SUPPORTED_PGBITS) == 0)
panic("flush_tlb_range: BUG: nbits=%lu\n", nbits);
}
start &= ~((1UL << nbits) - 1);
# ifdef CONFIG_SMP
platform_global_tlb_purge(start, end, nbits);
# else
do {
asm volatile ("ptc.l %0,%1" :: "r"(start), "r"(nbits<<2) : "memory");
start += (1UL << nbits);
} while (start < end);
# endif
ia64_insn_group_barrier();
ia64_srlz_i(); /* srlz.i implies srlz.d */
ia64_insn_group_barrier();
}
void __init
ia64_tlb_init (void)
{
ia64_ptce_info_t ptce_info;
ia64_get_ptce(&ptce_info);
local_cpu_data->ptce_base = ptce_info.base;
local_cpu_data->ptce_count[0] = ptce_info.count[0];
local_cpu_data->ptce_count[1] = ptce_info.count[1];
local_cpu_data->ptce_stride[0] = ptce_info.stride[0];
local_cpu_data->ptce_stride[1] = ptce_info.stride[1];
__flush_tlb_all(); /* nuke left overs from bootstrapping... */
}
|