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| author | Jon Medhurst <tixy@linaro.org> | 2013-06-07 10:35:35 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-06-17 10:30:49 +0100 |
| commit | 691557941af4c12bd307ad81a4d9fa9c7743ac28 (patch) | |
| tree | 7382502cccc9bff1e3ca38f353f335d70a376ded /arch/arm/mm/cache-v7.S | |
| parent | 509eb76ebf9771abc9fe51859382df2571f11447 (diff) | |
| download | linux-691557941af4c12bd307ad81a4d9fa9c7743ac28.tar.gz linux-691557941af4c12bd307ad81a4d9fa9c7743ac28.tar.bz2 linux-691557941af4c12bd307ad81a4d9fa9c7743ac28.zip | |
ARM: 7752/1: errata: LoUIS bit field in CLIDR register is incorrect
On Cortex-A9 before version r1p0, the LoUIS bit field of the CLIDR
register returns zero when it should return one. This leads to cache
maintenance operations which rely on this value to not function as
intended, causing data corruption.
The workaround for this errata is to detect affected CPUs and correct
the LoUIS value read.
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/cache-v7.S')
| -rw-r--r-- | arch/arm/mm/cache-v7.S | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S index 15451ee4acc8..515b00064da8 100644 --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S @@ -92,6 +92,14 @@ ENTRY(v7_flush_dcache_louis) mrc p15, 1, r0, c0, c0, 1 @ read clidr, r0 = clidr ALT_SMP(ands r3, r0, #(7 << 21)) @ extract LoUIS from clidr ALT_UP(ands r3, r0, #(7 << 27)) @ extract LoUU from clidr +#ifdef CONFIG_ARM_ERRATA_643719 + ALT_SMP(mrceq p15, 0, r2, c0, c0, 0) @ read main ID register + ALT_UP(moveq pc, lr) @ LoUU is zero, so nothing to do + ldreq r1, =0x410fc090 @ ID of ARM Cortex A9 r0p? + biceq r2, r2, #0x0000000f @ clear minor revision number + teqeq r2, r1 @ test for errata affected core and if so... + orreqs r3, #(1 << 21) @ fix LoUIS value (and set flags state to 'ne') +#endif ALT_SMP(mov r3, r3, lsr #20) @ r3 = LoUIS * 2 ALT_UP(mov r3, r3, lsr #26) @ r3 = LoUU * 2 moveq pc, lr @ return if level == 0 |