Re: [PATCH] irqchip/gic-v3: Fix IPRIORITYR can't perform byte operations in GIC-600
From: Lecopzer Chen
Date: Tue Mar 30 2021 - 10:25:47 EST
[...]
> > > >
> > > > From the architecture spec:
> > > >
> > > > <quote>
> > > > 11.1.3 GIC memory-mapped register access
> > > >
> > > > In any system, access to the following registers must be supported:
> > > >
> > > > [...]
> > > > * Byte accesses to:
> > > > - GICD_IPRIORITYR<n>.
> > > > - GICD_ITARGETSR<n>.
> > > > - GICD_SPENDSGIR<n>.
> > > > - GICD_CPENDSGIR<n>.
> > > > - GICR_IPRIORITYR<n>.
> > > > </quote>
> > > >
> > > > So if GIC600 doesn't follow this architectural requirement, this is a
> > > > HW erratum, and I want an actual description of the HW issue together
> > > > with an erratum number.
> > > >
> > > > Lorenzo, can you please investigate on your side?
> > >
> > > Sure - I will look into it and report back.
> >
> > Checked - I don't think this patch is needed so it should be dropped and
> > a follow-up discussion can continue in the relevant/appropriate forum -
> > if there is anything left to discuss.
>
> Thanks for having had a look. This really smells like an integration
> issue rather than an actual GIC bug.
>
> Lecopzer, please check with your HW people and potentially ARM, as I
> think you are looking at the wrong problem.
Thanks a lot for the suggestion and checking,
I think I'll back to disscuss with ARM and our HW team to figure out
the previous answer from ARM Support in detail.
Thanks again!
Lecopzer