Re: [PATCH] arm64: errata: Enable the AC03_CPU_38 workaround for ampere1a
From: Oliver Upton <hidden>
Date: 2024-08-26 23:24:02
Also in:
linux-doc, lkml
Hi D Scott, On Mon, Aug 26, 2024 at 02:59:33PM -0700, D Scott Phillips wrote:
quoted hunk ↗ jump to hunk
The ampere1a cpu is affected by erratum AC04_CPU_10 which is the same bug as AC03_CPU38. Add ampere1a to the AC03_CPU_38 workaround midr list. Signed-off-by: D Scott Phillips <redacted> --- Documentation/arch/arm64/silicon-errata.rst | 2 ++ arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/cputype.h | 2 ++ arch/arm64/kernel/cpu_errata.c | 1 + 4 files changed, 6 insertions(+), 1 deletion(-)diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index 50327c05be8d1..39c52385f11fb 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst@@ -55,6 +55,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | Ampere | AmpereOne | AC03_CPU_38 | AMPERE_ERRATUM_AC03_CPU_38 | +----------------+-----------------+-----------------+-----------------------------+ +| Ampere | AmpereOne AC04 | AC04_CPU_10 | AMPERE_ERRATUM_AC03_CPU_38 | ++----------------+-----------------+-----------------+-----------------------------+
We tend to stick the marketing term for a part in the second column so it is more recognizable for the user. Is this a placeholder for something different from "ampere1a"?
quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index f6b6b45073571..748aa536446ae 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c@@ -773,6 +773,7 @@ const struct arm64_cpu_capabilities arm64_errata[] = { .desc = "AmpereOne erratum AC03_CPU_38", .capability = ARM64_WORKAROUND_AMPERE_AC03_CPU_38, ERRATA_MIDR_ALL_VERSIONS(MIDR_AMPERE1), + ERRATA_MIDR_ALL_VERSIONS(MIDR_AMPERE1A),
This will break the workaround on AC03, since the second macro reassigns ::midr_range. You'll want to use ERRATA_MIDR_RANGE_LIST() instead w/ an array of affected MIDRs. -- Thanks, Oliver