Re: [PATCH] target/arm: Advertise Cortex-A53 erratum #843419 fix via REVIDR

[Richard Henderson]

On 2/15/24 06:02, Ard Biesheuvel wrote:
> From: Ard Biesheuvel <ardb@kernel.org>
>
> The Cortex-A53 r0p4 revision that QEMU emulates is affected by a CatA
> erratum #843419 (i.e., the most severe), which requires workarounds in
> the toolchain as well as the OS.
>
> Since the emulation is obviously not affected in the same way, we can
> indicate this via REVIDR bit #8, which on r0p4 has the meaning that no
> workarounds for erratum #843419 are needed.
>
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
>   target/arm/cpu64.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
> index 8e30a7993e..0f7a44a28f 100644
> --- a/target/arm/cpu64.c
> +++ b/target/arm/cpu64.c
> @@ -663,7 +663,7 @@ static void aarch64_a53_initfn(Object *obj)
>       set_feature(&cpu->env, ARM_FEATURE_PMU);
>       cpu->kvm_target = QEMU_KVM_ARM_TARGET_CORTEX_A53;
>       cpu->midr = 0x410fd034;
> -    cpu->revidr = 0x00000000;
> +    cpu->revidr = 0x00000100;

Is it worth indicating all three errata fixes (bits 7-9)?

Anyway,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~