[PATCH v3 00/25] x86: Enhance MTRR functionality to support multiple CPUs

Simon Glass sjg at chromium.org
Wed Jul 8 03:36:35 CEST 2020


Hi Bin,

On Tue, 7 Jul 2020 at 02:54, Bin Meng <bmeng.cn at gmail.com> wrote:
>
> Hi Simon,
>
> On Mon, Jul 6, 2020 at 11:37 AM Simon Glass <sjg at chromium.org> wrote:
> >
> > At present MTRRs are mirrored to the secondary CPUs only once, as those
> > CPUs are started up. But U-Boot may add more MTRRs later, e.g. if it
> > decides that a video console must be set up.
> >
> > This series enhances the x86 multi-processor support to allow MTRRs to
> > be updated at any time. It also updates the 'mtrr' command to support
> > setting the MTRRs on CPUs other than the boot CPU.
> >
>
> Testing this series on Minnowmax, the "mtrr" command fails:
>
> => mtrr
> CPU 0:
> Failed to read CPU 0 (err=-110)
>
> Could you please take a look?

Somehow I missed that sorry. I've had to make it optional, and enable
it only on coral for now. I suspect it might work on other boards but
they will need to be tested.

Will send v4 with a small number of changes.

Regards,
SImon


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