Re: [PATCH v1] drm/i915/dg2: enable G8 with a workaround

[Raag Jadav <raag.jadav@intel.com>]

On Wed, Oct 09, 2024 at 04:05:20PM +0300, Jani Nikula wrote:
> On Wed, 09 Oct 2024, Raag Jadav <raag.jadav@intel.com> wrote:
> > On Tue, Oct 08, 2024 at 08:24:42PM +0300, Jani Nikula wrote:
> >> On Mon, 07 Oct 2024, Raag Jadav <raag.jadav@intel.com> wrote:
> >> > +
> >> > +/* Wa_14022698589:dg2 */
> >> > +static void intel_enable_g8(struct intel_uncore *uncore)
> >> > +{
> >> > +	if (IS_DG2(uncore->i915)) {
> >> > +		switch (INTEL_DEVID(uncore->i915)) {
> >> 
> >> Even using INTEL_DEVID() is a no-go. There are currently four users, and
> >> even some of them are too much.
> >> 
> >> We try hard to abstract this stuff at a higher level, and there must be
> >> zero direct PCI ID checks in code other than the table driven device
> >> identification. Otherwise it's just impossible to figure out where we do
> >> platform specific stuff for each platform.
> >
> > Even if we use pci_match_id(), we'd need an explicit list to match against.
> 
> Well, we don't use that for individual workarounds or hacks either. When
> you think of using something like that, see what git grep says.
> 
> > Any better way?
> 
> You probably need to turn it into another subplatform, and add it in
> intel_device_info.c. You're probably going to need to rehash the
> INTEL_DG2_*_IDS PCI ID macros too. That's how we tell platforms apart at
> the PCI ID granularity.

Which would be controversial since the ids span across existing subplatforms,
which we don't want to break.

Don't we have quirk mask thing like display?

Raag