Peter,
I’ll talk with Shuichiro this coming Monday (here most of us on vacation),
and get back to you.

Itaru.

On Sat, May 7, 2022 at 1:34 Peter Maydell <peter.mayd...@linaro.org> wrote:

> On Fri, 6 May 2022 at 17:21, Peter Maydell <peter.mayd...@linaro.org>
> wrote:
> >
> > Make the GICv3 set its number of bits of physical priority from the
> > implementation-specific value provided in the CPU state struct, in
> > the same way we already do for virtual priority bits.  Because this
> > would be a migration compatibility break, we provide a property
> > force-8-bit-prio which is enabled for 7.0 and earlier versioned board
> > models to retain the legacy "always use 8 bits" behaviour.
> >
> > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
> > ---
> > I have guessed at the right value for the A64FX, but if we can
> > find the correct ICC_CTLR_EL1 value that would be better.
>
> Shuuichirou, Itaru: do either of you know the right setting for
> the A64FX for this? If you can find what the hardware value of
> the ICC_CTLR_EL3 or ICC_CTLR_EL1 register is (more specifically,
> the PRIBits subfield) that should be enough to tell us.
>
> > @@ -961,6 +964,12 @@ static void aarch64_a64fx_initfn(Object *obj)
> >      cpu->gic_num_lrs = 4;
> >      cpu->gic_vpribits = 5;
> >      cpu->gic_vprebits = 5;
> > +    /*
> > +     * TODO: What does the real A64FX GICv3 provide ?
> > +     * This is a guess based on what other Arm CPUs do; to find the
> correct
> > +     * answer we need the value of the A64FX's ICC_CTLR_EL1 register.
> > +     */
> > +    cpu->gic_pribits = 5;
> >
> >      /* Suppport of A64FX's vector length are 128,256 and 512bit only */
> >      aarch64_add_sve_properties(obj);
> > --
> > 2.25.1
>
> thanks
> -- PMM
>

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