Re: [RFC PATCH] irqchip/gic-v3: Add quirk for msm8996 secured registers

From: Stephen Boyd
Date: Thu Jun 14 2018 - 16:33:56 EST


Quoting Srinivas Kandagatla (2018-06-14 10:54:43)
> >
> >> +{
> >> + struct gic_chip_data *d = data;
> >> +
> >> + d->flags |= GICV3_FLAGS_WORKAROUND_IW_GICR_WAKER;
> >> +
> >> + return true;
> >> +}
> >> +
> >> +static const struct gic_quirk gicv3_quirks[] = {
> >> + {
> >> + .desc = "GICV3: Qualcomm MSM8996 WAKER IW",
> >
> > Please the erratum number in the message. It should read something like:
> >
> > "GICv3: Qualcomm erratum BIGNUMBERHERE"
> >
> >> + .iidr = 0x00001070, /* MSM8996 */
> >> + .mask = 0x0000ffff,
> >
> > Please match the full GICD_IIDR register, not just the implementer and
> > the revision. Unless you expect all the QC systems to have the same
> > behaviour?
> There seems to be more than one SoC that has this issue, I will dig up
> more info before sending next version.
>

It depends on the firmware and if that firmware decides to block or
allow access to this register space. I don't see how it can be quirked
based on the IIDR at all because there could be different firmware on
the board that doesn't block access to the register. Can a DT property
work?