diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2021-10-19 19:31:41 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2021-10-21 19:49:16 +0300 |
| commit | fa82d0b4b833790ac4572377fb777dcea24a9d69 (patch) | |
| tree | 08780ba656ecb6d78224b14a6434ce25f7c33ded /arch/arm64/tools | |
| parent | b9d216fcef4298de76519e2baeed69ba482467bd (diff) | |
| download | linux-fa82d0b4b833790ac4572377fb777dcea24a9d69.tar.xz | |
arm64: errata: Add workaround for TSB flush failures
Arm Neoverse-N2 (#2067961) and Cortex-A710 (#2054223) suffers
from errata, where a TSB (trace synchronization barrier)
fails to flush the trace data completely, when executed from
a trace prohibited region. In Linux we always execute it
after we have moved the PE to trace prohibited region. So,
we can apply the workaround every time a TSB is executed.
The work around is to issue two TSB consecutively.
NOTE: This errata is defined as LOCAL_CPU_ERRATUM, implying
that a late CPU could be blocked from booting if it is the
first CPU that requires the workaround. This is because we
do not allow setting a cpu_hwcaps after the SMP boot. The
other alternative is to use "this_cpu_has_cap()" instead
of the faster system wide check, which may be a bit of an
overhead, given we may have to do this in nvhe KVM host
before a guest entry.
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-4-suzuki.poulose@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/tools')
| -rw-r--r-- | arch/arm64/tools/cpucaps | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index 1ccb92165bd8..2102e15af43d 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -54,6 +54,7 @@ WORKAROUND_1463225 WORKAROUND_1508412 WORKAROUND_1542419 WORKAROUND_TRBE_OVERWRITE_FILL_MODE +WORKAROUND_TSB_FLUSH_FAILURE WORKAROUND_CAVIUM_23154 WORKAROUND_CAVIUM_27456 WORKAROUND_CAVIUM_30115 |