[PATCH 5/6] arm64: errata: Add QCOM_KRYO_5XX_GOLD to the spectre_bhb_k24_list

Dmitry Baryshkov dmitry.baryshkov at linaro.org
Mon Dec 9 15:07:38 PST 2024


On Mon, Dec 09, 2024 at 09:43:15AM -0800, Douglas Anderson wrote:
> Qualcomm Kryo 500-series Gold cores appear to have a derivative of an
> ARM Cortex A77 in them. Since A77 needs Spectre mitigation then the
> Kyro 500-series Gold cores also should need Spectre mitigation.
> 
> Signed-off-by: Douglas Anderson <dianders at chromium.org>
> ---
> Yes. I know. This patch DOESN'T COMPILE because
> MIDR_QCOM_KRYO_5XX_GOLD is not defined. That value needs to come from
> Qualcomm or from testing on hardware, which I don't have. Qualcomm
> needs to chime in to confirm that this Spectre mitigation is correct
> anyway, though. I'm including this patch so it's obvious that I think
> these cores also need the mitigation.

Kryo 5xx (SM8250) identify themselves as 0x41/0xd0d (Gold, Prime) and
0x51/0x805 (Silver)

> 
>  arch/arm64/kernel/proton-pack.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
> index b1881964e304..212481726f04 100644
> --- a/arch/arm64/kernel/proton-pack.c
> +++ b/arch/arm64/kernel/proton-pack.c
> @@ -867,6 +867,7 @@ u8 spectre_bhb_loop_affected(int scope)
>  			MIDR_ALL_VERSIONS(MIDR_CORTEX_A77),
>  			MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1),
>  			MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_GOLD),
> +			MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_5XX_GOLD),
>  			{},
>  		};
>  		static const struct midr_range spectre_bhb_k11_list[] = {
> -- 
> 2.47.0.338.g60cca15819-goog
> 

-- 
With best wishes
Dmitry



More information about the linux-arm-kernel mailing list