Re: [PATCH 3/4] irqchip, gicv3: Implement Cavium ThunderX erratum 23154

From: Robert Richter
Date: Wed Jul 08 2015 - 06:29:13 EST


Marc,

On 06.07.15 11:43:02, Marc Zyngier wrote:
> On 30/06/15 15:14, Robert Richter wrote:
> > static const struct gic_capabilities gicv3_errata[] = {
> > {
> > + .desc = "GIC: Cavium erratum 23154",
> > + .id = 0xa100034c, /* ThunderX pass 1.x */
> > + .mask = 0xffff0fff,
> > + .init = gicv3_enable_cavium_thunderx,
> > + },
> > + {
> > }
> > };
> >
> >
>
> How does this work when running a guest? Does the virtualized access
> suffer from the same erratum? If that's the case, we need a better
> workaround...

We need to apply the workaround also for guests. So you are right,
evaluating GICD_IIDR does not enable the workaround then as the
register is emulated with ARM as implementer.

We considering MIDR_EL1 as a version check for this errata now. This
should be the host's cpuid when running as a guest, right?

Thanks,

-Robert
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