Re: [PATCH 4/4] arm64: cpu_errata: Apply Erratum 845719 to KRYO2XX Silver

[Sai Prakash Ranjan]

Hi Marc,

On 2020-11-05 14:59, Marc Zyngier wrote:
> On 2020-11-04 23:22, Konrad Dybcio wrote:
> > QCOM KRYO2XX Silver cores are Cortex-A53 based and are
> > susceptible to the 845719 erratum. Add them to the lookup
> > list to apply the erratum.
> >
> > Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxx>
> > ---
> >  arch/arm64/kernel/cpu_errata.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/cpu_errata.c 
> > b/arch/arm64/kernel/cpu_errata.c
> > index 61314fd70f13..cafaf0da05b7 100644
> > --- a/arch/arm64/kernel/cpu_errata.c
> > +++ b/arch/arm64/kernel/cpu_errata.c
> > @@ -299,6 +299,8 @@ static const struct midr_range 
> > erratum_845719_list[] = {
> >  	MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 4),
> >  	/* Brahma-B53 r0p[0] */
> >  	MIDR_REV(MIDR_BRAHMA_B53, 0, 0),
> > +	/* Kryo2XX Silver rAp4 */
> > +	MIDR_REV(MIDR_QCOM_KRYO_2XX_SILVER, 0xa, 0x4),
>
> Is this the only affected version? If this is actually an A53, how do 
> the
> revisions map between Kryo and Cortex cores?

From what I see from the docs, this is the only version used
in MSM8998(silver cores are based on Cortex A53) and it maps
to r0p4. @Konrad, can you include (rap4 => r0p4) in comment.

Thanks,
Sai

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