diff options
| author | Will Deacon <will.deacon@arm.com> | 2011-11-22 18:30:28 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2011-12-08 11:30:38 +0100 |
| commit | d675d0bc47f28c5414fbbe17fcc801f69c45b960 (patch) | |
| tree | 78d7b2c43650d6af96caac9e631409cf15c8f25a | |
| parent | ARM: LPAE: Factor out classic-MMU specific code into proc-v7-2level.S (diff) | |
| download | linux-d675d0bc47f28c5414fbbe17fcc801f69c45b960.tar.xz linux-d675d0bc47f28c5414fbbe17fcc801f69c45b960.zip | |
ARM: LPAE: add ISBs around MMU enabling code
Before we enable the MMU, we must ensure that the TTBR registers contain
sane values. After the MMU has been enabled, we jump to the *virtual*
address of the following function, so we also need to ensure that the
SCTLR write has taken effect.
This patch adds ISB instructions around the SCTLR write to ensure the
visibility of the above.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm/boot/compressed/head.S | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/assembler.h | 11 | ||||
| -rw-r--r-- | arch/arm/kernel/head.S | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/sleep.S | 2 |
4 files changed, 16 insertions, 0 deletions
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index c2effc917254..c5d60250d43d 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -659,6 +659,7 @@ __armv7_mmu_cache_on: mcrne p15, 0, r3, c2, c0, 0 @ load page table pointer mcrne p15, 0, r1, c3, c0, 0 @ load domain access control #endif + mcr p15, 0, r0, c7, c5, 4 @ ISB mcr p15, 0, r0, c1, c0, 0 @ load control register mrc p15, 0, r0, c1, c0, 0 @ and read it back mov r0, #0 diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 29035e86a59d..b6e65dedfd71 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -187,6 +187,17 @@ #endif /* + * Instruction barrier + */ + .macro instr_sync +#if __LINUX_ARM_ARCH__ >= 7 + isb +#elif __LINUX_ARM_ARCH__ == 6 + mcr p15, 0, r0, c7, c5, 4 +#endif + .endm + +/* * SMP data memory barrier */ .macro smp_dmb mode diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 64e9943ea4f0..54eb94aff6cd 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -401,8 +401,10 @@ ENDPROC(__enable_mmu) .pushsection .idmap.text, "ax" ENTRY(__turn_mmu_on) mov r0, r0 + instr_sync mcr p15, 0, r0, c1, c0, 0 @ write control reg mrc p15, 0, r3, c0, c0, 0 @ read id reg + instr_sync mov r3, r3 mov r3, r13 mov pc, r3 diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S index 9e64231c8cfe..1f268bda4552 100644 --- a/arch/arm/kernel/sleep.S +++ b/arch/arm/kernel/sleep.S @@ -57,8 +57,10 @@ ENDPROC(cpu_suspend_abort) .pushsection .idmap.text,"ax" ENTRY(cpu_resume_mmu) ldr r3, =cpu_resume_after_mmu + instr_sync mcr p15, 0, r0, c1, c0, 0 @ turn on MMU, I-cache, etc mrc p15, 0, r0, c0, c0, 0 @ read id reg + instr_sync mov r0, r0 mov r0, r0 mov pc, r3 @ jump to virtual address |