linux/arch/arm/mm/tlb-v7.S
Catalin Marinas faa7bc51c1 Check whether the TLB operations need broadcasting on SMP systems
ARMv7 SMP hardware can handle the TLB maintenance operations
broadcasting in hardware so that the software can avoid the costly IPIs.
This patch adds the necessary checks (the MMFR3 CPUID register) to avoid
the broadcasting if already supported by the hardware.

(this patch is based on the work done by Tony Thompson @ ARM)

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2009-05-30 14:00:14 +01:00

97 lines
2.4 KiB
ArmAsm

/*
* linux/arch/arm/mm/tlb-v7.S
*
* Copyright (C) 1997-2002 Russell King
* Modified for ARMv7 by Catalin Marinas
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* ARM architecture version 6 TLB handling functions.
* These assume a split I/D TLB.
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/page.h>
#include <asm/tlbflush.h>
#include "proc-macros.S"
/*
* v7wbi_flush_user_tlb_range(start, end, vma)
*
* Invalidate a range of TLB entries in the specified address space.
*
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
* - vma - vma_struct describing address range
*
* It is assumed that:
* - the "Invalidate single entry" instruction will invalidate
* both the I and the D TLBs on Harvard-style TLBs
*/
ENTRY(v7wbi_flush_user_tlb_range)
vma_vm_mm r3, r2 @ get vma->vm_mm
mmid r3, r3 @ get vm_mm->context.id
dsb
mov r0, r0, lsr #PAGE_SHIFT @ align address
mov r1, r1, lsr #PAGE_SHIFT
asid r3, r3 @ mask ASID
orr r0, r3, r0, lsl #PAGE_SHIFT @ Create initial MVA
mov r1, r1, lsl #PAGE_SHIFT
vma_vm_flags r2, r2 @ get vma->vm_flags
1:
#ifdef CONFIG_SMP
mcr p15, 0, r0, c8, c3, 1 @ TLB invalidate U MVA (shareable)
#else
mcr p15, 0, r0, c8, c7, 1 @ TLB invalidate U MVA
#endif
add r0, r0, #PAGE_SZ
cmp r0, r1
blo 1b
mov ip, #0
mcr p15, 0, ip, c7, c5, 6 @ flush BTAC/BTB
dsb
mov pc, lr
ENDPROC(v7wbi_flush_user_tlb_range)
/*
* v7wbi_flush_kern_tlb_range(start,end)
*
* Invalidate a range of kernel TLB entries
*
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
*/
ENTRY(v7wbi_flush_kern_tlb_range)
dsb
mov r0, r0, lsr #PAGE_SHIFT @ align address
mov r1, r1, lsr #PAGE_SHIFT
mov r0, r0, lsl #PAGE_SHIFT
mov r1, r1, lsl #PAGE_SHIFT
1:
#ifdef CONFIG_SMP
mcr p15, 0, r0, c8, c3, 1 @ TLB invalidate U MVA (shareable)
#else
mcr p15, 0, r0, c8, c7, 1 @ TLB invalidate U MVA
#endif
add r0, r0, #PAGE_SZ
cmp r0, r1
blo 1b
mov r2, #0
mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
dsb
isb
mov pc, lr
ENDPROC(v7wbi_flush_kern_tlb_range)
__INIT
.type v7wbi_tlb_fns, #object
ENTRY(v7wbi_tlb_fns)
.long v7wbi_flush_user_tlb_range
.long v7wbi_flush_kern_tlb_range
.long v7wbi_tlb_flags
.size v7wbi_tlb_fns, . - v7wbi_tlb_fns