[PATCH 0/3] arm64: Enable work around for Cortex-A55 erratum 1024718

Suzuki K Poulose suzuki.poulose at arm.com
Tue Jan 16 02:23:20 PST 2018


Arm Cortex-A55 suffers from erratum 1024718, where update of DBM/AP bits
without a break-before-make sequence might result in an incorrect update
of the hardware dirty bit. The work around is to disable the DBM feature
on the affected cores. The kernel can cope with CPUs running with and
without the feature. So to avoid the complications of handling secondary
CPUs brought up later (e.g, userspace) do not tie this to
arm64_cpu_capability framework. Instead, add a check in the early CPU
boot before we enabel the TCR bits.

Suzuki K Poulose (3):
  arm64: Update MIDR definitions for Arm Cortex-A cores
  arm64: Add assembly helpers for MIDR range check
  arm64: Add work around for Arm Cortex-A55 Erratum 1024718

 Documentation/arm64/silicon-errata.txt |  1 +
 arch/arm64/Kconfig                     | 14 ++++++++++++
 arch/arm64/include/asm/assembler.h     | 41 ++++++++++++++++++++++++++++++++++
 arch/arm64/include/asm/cputype.h       |  4 ++++
 arch/arm64/mm/proc.S                   |  5 +++++
 5 files changed, 65 insertions(+)

-- 
2.13.6




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