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@xxxxxxxxxxxx>
> ---
> 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
