linux_dsm_epyc7002/arch/csky/mm/tlb.c
Guo Ren 4e562c1166 csky: Improve tlb operation with help of asid
There are two generations of tlb operation instruction for C-SKY.
First generation is use mcr register and it need software do more
things, second generation is use specific instructions, eg:
 tlbi.va, tlbi.vas, tlbi.alls

We implemented the following functions:

 - flush_tlb_range (a range of entries)
 - flush_tlb_page (one entry)

 Above functions use asid from vma->mm to invalid tlb entries and
 we could use tlbi.vas instruction for newest generation csky cpu.

 - flush_tlb_kernel_range
 - flush_tlb_one

 Above functions don't care asid and it invalid the tlb entries only
 with vpn and we could use tlbi.vaas instruction for newest generat-
 ion csky cpu.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2019-07-19 14:21:36 +08:00

172 lines
3.3 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/pgtable.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
asm volatile("tlbi.asids %0"::"r"(cpu_asid(mm)));
#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
while (start < end) {
asm volatile("tlbi.vas %0"::"r"(start | newpid));
start += 2*PAGE_SIZE;
}
sync_is();
#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
while (start < end) {
asm volatile("tlbi.vaas %0"::"r"(start));
start += 2*PAGE_SIZE;
}
sync_is();
#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
asm volatile("tlbi.vas %0"::"r"(addr | newpid));
sync_is();
#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
asm volatile("tlbi.vaas %0"::"r"(addr));
sync_is();
#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);