https://github.com/torvalds/linux
Tip revision: 11a48a5a18c63fd7621bb050228cebf13566e4d8 authored by Linus Torvalds on 16 February 2020, 21:16:59 UTC
Linux 5.6-rc2
Linux 5.6-rc2
Tip revision: 11a48a5
smp_tlb.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/kernel/smp_tlb.c
*
* Copyright (C) 2002 ARM Limited, All Rights Reserved.
*/
#include <linux/preempt.h>
#include <linux/smp.h>
#include <linux/uaccess.h>
#include <asm/smp_plat.h>
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
/**********************************************************************/
/*
* TLB operations
*/
struct tlb_args {
struct vm_area_struct *ta_vma;
unsigned long ta_start;
unsigned long ta_end;
};
static inline void ipi_flush_tlb_all(void *ignored)
{
local_flush_tlb_all();
}
static inline void ipi_flush_tlb_mm(void *arg)
{
struct mm_struct *mm = (struct mm_struct *)arg;
local_flush_tlb_mm(mm);
}
static inline void ipi_flush_tlb_page(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
unsigned int __ua_flags = uaccess_save_and_enable();
local_flush_tlb_page(ta->ta_vma, ta->ta_start);
uaccess_restore(__ua_flags);
}
static inline void ipi_flush_tlb_kernel_page(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
local_flush_tlb_kernel_page(ta->ta_start);
}
static inline void ipi_flush_tlb_range(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
unsigned int __ua_flags = uaccess_save_and_enable();
local_flush_tlb_range(ta->ta_vma, ta->ta_start, ta->ta_end);
uaccess_restore(__ua_flags);
}
static inline void ipi_flush_tlb_kernel_range(void *arg)
{
struct tlb_args *ta = (struct tlb_args *)arg;
local_flush_tlb_kernel_range(ta->ta_start, ta->ta_end);
}
static inline void ipi_flush_bp_all(void *ignored)
{
local_flush_bp_all();
}
#ifdef CONFIG_ARM_ERRATA_798181
bool (*erratum_a15_798181_handler)(void);
static bool erratum_a15_798181_partial(void)
{
asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (0));
dsb(ish);
return false;
}
static bool erratum_a15_798181_broadcast(void)
{
asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (0));
dsb(ish);
return true;
}
void erratum_a15_798181_init(void)
{
unsigned int midr = read_cpuid_id();
unsigned int revidr = read_cpuid(CPUID_REVIDR);
/* Brahma-B15 r0p0..r0p2 affected
* Cortex-A15 r0p0..r3p3 w/o ECO fix affected
* Fixes applied to A15 with respect to the revision and revidr are:
*
* r0p0-r2p1: No fixes applied
* r2p2,r2p3:
* REVIDR[4]: 798181 Moving a virtual page that is being accessed
* by an active process can lead to unexpected behavior
* REVIDR[9]: Not defined
* r2p4,r3p0,r3p1,r3p2:
* REVIDR[4]: 798181 Moving a virtual page that is being accessed
* by an active process can lead to unexpected behavior
* REVIDR[9]: 798181 Moving a virtual page that is being accessed
* by an active process can lead to unexpected behavior
* - This is an update to a previously released ECO.
* r3p3:
* REVIDR[4]: Reserved
* REVIDR[9]: 798181 Moving a virtual page that is being accessed
* by an active process can lead to unexpected behavior
* - This is an update to a previously released ECO.
*
* Handling:
* REVIDR[9] set -> No WA
* REVIDR[4] set, REVIDR[9] cleared -> Partial WA
* Both cleared -> Full WA
*/
if ((midr & 0xff0ffff0) == 0x420f00f0 && midr <= 0x420f00f2) {
erratum_a15_798181_handler = erratum_a15_798181_broadcast;
} else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x412fc0f2) {
erratum_a15_798181_handler = erratum_a15_798181_broadcast;
} else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x412fc0f4) {
if (revidr & 0x10)
erratum_a15_798181_handler =
erratum_a15_798181_partial;
else
erratum_a15_798181_handler =
erratum_a15_798181_broadcast;
} else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x413fc0f3) {
if ((revidr & 0x210) == 0)
erratum_a15_798181_handler =
erratum_a15_798181_broadcast;
else if (revidr & 0x10)
erratum_a15_798181_handler =
erratum_a15_798181_partial;
} else if ((midr & 0xff0ffff0) == 0x410fc0f0 && midr < 0x414fc0f0) {
if ((revidr & 0x200) == 0)
erratum_a15_798181_handler =
erratum_a15_798181_partial;
}
}
#endif
static void ipi_flush_tlb_a15_erratum(void *arg)
{
dmb();
}
static void broadcast_tlb_a15_erratum(void)
{
if (!erratum_a15_798181())
return;
smp_call_function(ipi_flush_tlb_a15_erratum, NULL, 1);
}
static void broadcast_tlb_mm_a15_erratum(struct mm_struct *mm)
{
int this_cpu;
cpumask_t mask = { CPU_BITS_NONE };
if (!erratum_a15_798181())
return;
this_cpu = get_cpu();
a15_erratum_get_cpumask(this_cpu, mm, &mask);
smp_call_function_many(&mask, ipi_flush_tlb_a15_erratum, NULL, 1);
put_cpu();
}
void flush_tlb_all(void)
{
if (tlb_ops_need_broadcast())
on_each_cpu(ipi_flush_tlb_all, NULL, 1);
else
__flush_tlb_all();
broadcast_tlb_a15_erratum();
}
void flush_tlb_mm(struct mm_struct *mm)
{
if (tlb_ops_need_broadcast())
on_each_cpu_mask(mm_cpumask(mm), ipi_flush_tlb_mm, mm, 1);
else
__flush_tlb_mm(mm);
broadcast_tlb_mm_a15_erratum(mm);
}
void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
{
if (tlb_ops_need_broadcast()) {
struct tlb_args ta;
ta.ta_vma = vma;
ta.ta_start = uaddr;
on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_page,
&ta, 1);
} else
__flush_tlb_page(vma, uaddr);
broadcast_tlb_mm_a15_erratum(vma->vm_mm);
}
void flush_tlb_kernel_page(unsigned long kaddr)
{
if (tlb_ops_need_broadcast()) {
struct tlb_args ta;
ta.ta_start = kaddr;
on_each_cpu(ipi_flush_tlb_kernel_page, &ta, 1);
} else
__flush_tlb_kernel_page(kaddr);
broadcast_tlb_a15_erratum();
}
void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if (tlb_ops_need_broadcast()) {
struct tlb_args ta;
ta.ta_vma = vma;
ta.ta_start = start;
ta.ta_end = end;
on_each_cpu_mask(mm_cpumask(vma->vm_mm), ipi_flush_tlb_range,
&ta, 1);
} else
local_flush_tlb_range(vma, start, end);
broadcast_tlb_mm_a15_erratum(vma->vm_mm);
}
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
if (tlb_ops_need_broadcast()) {
struct tlb_args ta;
ta.ta_start = start;
ta.ta_end = end;
on_each_cpu(ipi_flush_tlb_kernel_range, &ta, 1);
} else
local_flush_tlb_kernel_range(start, end);
broadcast_tlb_a15_erratum();
}
void flush_bp_all(void)
{
if (tlb_ops_need_broadcast())
on_each_cpu(ipi_flush_bp_all, NULL, 1);
else
__flush_bp_all();
}