diff options
| author | Anshuman Khandual <anshuman.khandual@arm.com> | 2022-01-25 15:20:36 +0100 |
|---|---|---|
| committer | Suzuki K Poulose <suzuki.poulose@arm.com> | 2022-03-11 11:07:04 +0100 |
| commit | f209e9fe5bd7614b30b050f2095e80b77b99c333 (patch) | |
| tree | 2469728752837404dbaf6f93d75ef20c7f53a315 /arch | |
| parent | coresight: trbe: Work around the ignored system register writes (diff) | |
| download | linux-f209e9fe5bd7614b30b050f2095e80b77b99c333.tar.xz linux-f209e9fe5bd7614b30b050f2095e80b77b99c333.zip | |
coresight: trbe: Work around the invalid prohibited states
TRBE implementations affected by Arm erratum #2038923 might get TRBE into
an inconsistent view on whether trace is prohibited within the CPU. As a
result, the trace buffer or trace buffer state might be corrupted. This
happens after TRBE buffer has been enabled by setting TRBLIMITR_EL1.E,
followed by just a single context synchronization event before execution
changes from a context, in which trace is prohibited to one where it isn't,
or vice versa. In these mentioned conditions, the view of whether trace is
prohibited is inconsistent between parts of the CPU, and the trace buffer
or the trace buffer state might be corrupted.
Work around this problem in the TRBE driver by preventing an inconsistent
view of whether the trace is prohibited or not based on TRBLIMITR_EL1.E by
immediately following a change to TRBLIMITR_EL1.E with at least one ISB
instruction before an ERET, or two ISB instructions if no ERET is to take
place. This just updates the TRBE driver as required.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1643120437-14352-7-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 93980bf31e2c..8c7df3405de2 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -824,7 +824,7 @@ config ARM64_ERRATUM_2064142 config ARM64_ERRATUM_2038923 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable" - depends on COMPILE_TEST # Until the CoreSight TRBE driver changes are in + depends on CORESIGHT_TRBE default y help This option adds the workaround for ARM Cortex-A510 erratum 2038923. |