diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2018-03-26 15:12:49 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-16 10:08:42 +0200 |
| commit | b8c320884eff003581ee61c5970a2e83f513eff1 (patch) | |
| tree | c230a2708948767ca798ed75098a6e6160d14b90 /arch/arm64/mm | |
| parent | b8bf4b886b82585202ab4ee169718656661cb89e (diff) | |
arm64: Add work around for Arm Cortex-A55 Erratum 1024718
commit ece1397cbc89c51914fae1aec729539cfd8bd62b upstream.
Some variants of the Arm Cortex-55 cores (r0p0, r0p1, r1p0) suffer
from an erratum 1024718, which causes incorrect updates when DBM/AP
bits in a page table entry is modified without a break-before-make
sequence. The work around is to skip enabling the hardware DBM feature
on the affected cores. The hardware Access Flag management features
is not affected. There are some other cores suffering from this
errata, which could be added to the midr_list to trigger the work
around.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: ckadabi@codeaurora.org
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/proc.S | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 619da1cbd32b..66cce2138f95 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -425,6 +425,11 @@ ENTRY(__cpu_setup) cbz x9, 2f cmp x9, #2 b.lt 1f +#ifdef CONFIG_ARM64_ERRATUM_1024718 + /* Disable hardware DBM on Cortex-A55 r0p0, r0p1 & r1p0 */ + cpu_midr_match MIDR_CORTEX_A55, MIDR_CPU_VAR_REV(0, 0), MIDR_CPU_VAR_REV(1, 0), x1, x2, x3, x4 + cbnz x1, 1f +#endif orr x10, x10, #TCR_HD // hardware Dirty flag update 1: orr x10, x10, #TCR_HA // hardware Access flag update 2: |