linux/arch/csky/mm/tlb.c
Guo Ren 3b756ccddb csky: Fix TLB maintenance synchronization problem
TLB invalidate didn't contain a barrier operation in csky cpu and
we need to prevent previous PTW response after TLB invalidation
instruction. Of cause, the ASID changing also needs to take care
of the issue.

CPU0                    CPU1
===============         ===============
set_pte
sync_is()        ->     See the previous set_pte for all harts
tlbi.vas         ->     Invalidate all harts TLB entry & flush pipeline

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
2021-01-12 09:52:41 +08:00

199 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <asm/mmu_context.h>
#include <asm/setup.h>
/*
* One C-SKY MMU TLB entry contain two PFN/page entry, ie:
* 1VPN -> 2PFN
*/
#define TLB_ENTRY_SIZE (PAGE_SIZE * 2)
#define TLB_ENTRY_SIZE_MASK (PAGE_MASK << 1)
void flush_tlb_all(void)
{
tlb_invalid_all();
}
void flush_tlb_mm(struct mm_struct *mm)
{
#ifdef CONFIG_CPU_HAS_TLBI
sync_is();
asm volatile(
"tlbi.asids %0 \n"
"sync.i \n"
:
: "r" (cpu_asid(mm))
: "memory");
#else
tlb_invalid_all();
#endif
}
/*
* MMU operation regs only could invalid tlb entry in jtlb and we
* need change asid field to invalid I-utlb & D-utlb.
*/
#ifndef CONFIG_CPU_HAS_TLBI
#define restore_asid_inv_utlb(oldpid, newpid) \
do { \
if (oldpid == newpid) \
write_mmu_entryhi(oldpid + 1); \
write_mmu_entryhi(oldpid); \
} while (0)
#endif
void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
unsigned long newpid = cpu_asid(vma->vm_mm);
start &= TLB_ENTRY_SIZE_MASK;
end += TLB_ENTRY_SIZE - 1;
end &= TLB_ENTRY_SIZE_MASK;
#ifdef CONFIG_CPU_HAS_TLBI
sync_is();
while (start < end) {
asm volatile(
"tlbi.vas %0 \n"
:
: "r" (start | newpid)
: "memory");
start += 2*PAGE_SIZE;
}
asm volatile("sync.i\n");
#else
{
unsigned long flags, oldpid;
local_irq_save(flags);
oldpid = read_mmu_entryhi() & ASID_MASK;
while (start < end) {
int idx;
write_mmu_entryhi(start | newpid);
start += 2*PAGE_SIZE;
tlb_probe();
idx = read_mmu_index();
if (idx >= 0)
tlb_invalid_indexed();
}
restore_asid_inv_utlb(oldpid, newpid);
local_irq_restore(flags);
}
#endif
}
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
start &= TLB_ENTRY_SIZE_MASK;
end += TLB_ENTRY_SIZE - 1;
end &= TLB_ENTRY_SIZE_MASK;
#ifdef CONFIG_CPU_HAS_TLBI
sync_is();
while (start < end) {
asm volatile(
"tlbi.vaas %0 \n"
:
: "r" (start)
: "memory");
start += 2*PAGE_SIZE;
}
asm volatile("sync.i\n");
#else
{
unsigned long flags, oldpid;
local_irq_save(flags);
oldpid = read_mmu_entryhi() & ASID_MASK;
while (start < end) {
int idx;
write_mmu_entryhi(start | oldpid);
start += 2*PAGE_SIZE;
tlb_probe();
idx = read_mmu_index();
if (idx >= 0)
tlb_invalid_indexed();
}
restore_asid_inv_utlb(oldpid, oldpid);
local_irq_restore(flags);
}
#endif
}
void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
{
int newpid = cpu_asid(vma->vm_mm);
addr &= TLB_ENTRY_SIZE_MASK;
#ifdef CONFIG_CPU_HAS_TLBI
sync_is();
asm volatile(
"tlbi.vas %0 \n"
"sync.i \n"
:
: "r" (addr | newpid)
: "memory");
#else
{
int oldpid, idx;
unsigned long flags;
local_irq_save(flags);
oldpid = read_mmu_entryhi() & ASID_MASK;
write_mmu_entryhi(addr | newpid);
tlb_probe();
idx = read_mmu_index();
if (idx >= 0)
tlb_invalid_indexed();
restore_asid_inv_utlb(oldpid, newpid);
local_irq_restore(flags);
}
#endif
}
void flush_tlb_one(unsigned long addr)
{
addr &= TLB_ENTRY_SIZE_MASK;
#ifdef CONFIG_CPU_HAS_TLBI
sync_is();
asm volatile(
"tlbi.vaas %0 \n"
"sync.i \n"
:
: "r" (addr)
: "memory");
#else
{
int oldpid, idx;
unsigned long flags;
local_irq_save(flags);
oldpid = read_mmu_entryhi() & ASID_MASK;
write_mmu_entryhi(addr | oldpid);
tlb_probe();
idx = read_mmu_index();
if (idx >= 0)
tlb_invalid_indexed();
restore_asid_inv_utlb(oldpid, oldpid);
local_irq_restore(flags);
}
#endif
}
EXPORT_SYMBOL(flush_tlb_one);