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authorWill Deacon <will.deacon@arm.com>2014-02-07 19:12:20 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-03-06 21:30:01 -0800
commit1266f2d31159a79507aa299defeee54afccf1e15 (patch)
tree6f9b3b8e31b7a30a42f0dff8e1a5756f39ae45df /arch
parent1dca10b4c8528298fe5cf40cdbf4a480f9b0a429 (diff)
downloadlinaro-lsk-1266f2d31159a79507aa299defeee54afccf1e15.tar.gz
ARM: 7953/1: mm: ensure TLB invalidation is complete before enabling MMU
commit bae0ca2bc550d1ec6a118fb8f2696f18c4da3d8e upstream. During __v{6,7}_setup, we invalidate the TLBs since we are about to enable the MMU on return to head.S. Unfortunately, without a subsequent dsb instruction, the invalidation is not guaranteed to have completed by the time we write to the sctlr, potentially exposing us to junk/stale translations cached in the TLB. This patch reworks the init functions so that the dsb used to ensure completion of cache/predictor maintenance is also used to ensure completion of the TLB invalidation. Reported-by: Albin Tonnerre <Albin.Tonnerre@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mm/proc-v6.S3
-rw-r--r--arch/arm/mm/proc-v7.S2
2 files changed, 3 insertions, 2 deletions
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S
index 919405e20b8..d0735281958 100644
--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -206,7 +206,6 @@ __v6_setup:
mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache
mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache
- mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
#ifdef CONFIG_MMU
mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs
mcr p15, 0, r0, c2, c0, 2 @ TTB control register
@@ -216,6 +215,8 @@ __v6_setup:
ALT_UP(orr r8, r8, #TTB_FLAGS_UP)
mcr p15, 0, r8, c2, c0, 1 @ load TTB1
#endif /* CONFIG_MMU */
+ mcr p15, 0, r0, c7, c10, 4 @ drain write buffer and
+ @ complete invalidations
adr r5, v6_crval
ldmia r5, {r5, r6}
#ifdef CONFIG_CPU_ENDIAN_BE8
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 5fbccee5f64..19da84172cc 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -329,7 +329,6 @@ __v7_setup:
3: mov r10, #0
mcr p15, 0, r10, c7, c5, 0 @ I+BTB cache invalidate
- dsb
#ifdef CONFIG_MMU
mcr p15, 0, r10, c8, c7, 0 @ invalidate I + D TLBs
v7_ttb_setup r10, r4, r8, r5 @ TTBCR, TTBRx setup
@@ -338,6 +337,7 @@ __v7_setup:
mcr p15, 0, r5, c10, c2, 0 @ write PRRR
mcr p15, 0, r6, c10, c2, 1 @ write NMRR
#endif
+ dsb @ Complete invalidations
#ifndef CONFIG_ARM_THUMBEE
mrc p15, 0, r0, c0, c1, 0 @ read ID_PFR0 for ThumbEE
and r0, r0, #(0xf << 12) @ ThumbEE enabled field