Re: [PATCH v3 15/16] arm64: errata: Advertise the workaround for TSB flush failures

On 11/10/2021 11:18, Will Deacon wrote:

On Fri, Oct 08, 2021 at 07:29:05PM +0100, Suzuki K Poulose wrote:

...

Advertise the workaround for the TSB flush failures via Kconfig entries.

Cc: Will Deacon will@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Mathieu Poirier mathieu.poirier@linaro.org Cc: Anshuman Khandual anshuman.khandual@arm.com Cc: Marc Zyngier maz@kernel.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org Acked-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com

---

Changes since previous:

• Split the Kconfig/erratum updates to keep the conflicts minimal with the other Kconfig updates in TRBE errata I have retained the tags

---

Documentation/arm64/silicon-errata.rst | 4 ++++ arch/arm64/Kconfig | 31 ++++++++++++++++++++++++++ 2 files changed, 35 insertions(+)

diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index 2f99229d993c..569a92411dcd 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -94,6 +94,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A710 | #2119858 | ARM64_ERRATUM_2119858 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A710 | #2054223 | ARM64_ERRATUM_2054223 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1188873,1418040| ARM64_ERRATUM_1418040 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1349291 | N/A | @@ -102,6 +104,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #2139208 | ARM64_ERRATUM_2139208 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-N2 | #2067961 | ARM64_ERRATUM_2067961 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-500 | #841119,826419 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +----------------+-----------------+-----------------+-----------------------------+ diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index eac4030322df..0764774e12bb 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -705,6 +705,37 @@ config ARM64_ERRATUM_2139208 If unsure, say Y. +config ARM64_WORKAROUND_TSB_FLUSH_FAILURE

• bool

+config ARM64_ERRATUM_2054223

• bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
• default y
• help

•  Enable workaround for ARM Cortex-A710 erratum 2054223
  

•  Affected cores may fail to flush the trace data on a TSB instruction, when
  

•  the PE is in trace prohibited state. This will cause losing a few bytes
  

•  of the trace cached.
  

•  Workaround is to issue two TSB consecutively on affected cores.
  

•  If unsure, say Y.
  

+config ARM64_ERRATUM_2067961

• bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
• default y
• help

•  Enable workaround for ARM Neoverse-N2 erratum 2067961
  

•  Affected cores may fail to flush the trace data on a TSB instruction, when
  

•  the PE is in trace prohibited state. This will cause losing a few bytes
  

•  of the trace cached.
  

•  Workaround is to issue two TSB consecutively on affected cores.
  

•  If unsure, say Y.
  

Shouldn't these two be selecting the workaround?

doh! I have given myself a slap for this and fixed it locally.

Suzuki