Re: [PATCH 14/49] drm/i915/bxt: add GEN8_SDEUNIT_CLOCK_GATE_DISABLE workaround

Imre Deak
2015-03-20T10:37:06Z

On Fri, 2015-03-20 at 09:08 +0000, Nick Hoath wrote:
> On 17/03/2015 13:06, Imre Deak wrote:
> > On ti, 2015-03-17 at 11:35 +0100, Daniel Vetter wrote:
> >> On Tue, Mar 17, 2015 at 11:39:40AM +0200, Imre Deak wrote:
> >>> Signed-off-by: Imre Deak <imre.deak@intel.com>
> >>> ---
> >>> drivers/gpu/drm/i915/intel_pm.c | 11 +++++++++++
> >>> 1 file changed, 11 insertions(+)
> >>>
> >>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> >>> index 3d4a7c3..d5dd0b3 100644
> >>> --- a/drivers/gpu/drm/i915/intel_pm.c
> >>> +++ b/drivers/gpu/drm/i915/intel_pm.c
> >>> @@ -96,7 +96,18 @@ static void skl_init_clock_gating(struct drm_device *dev)
> >>>
> >>> static void bxt_init_clock_gating(struct drm_device *dev)
> >>> {
> >>> + struct drm_i915_private *dev_priv = dev->dev_private;
> >>> +
> >>> gen9_init_clock_gating(dev);
> >>> +
> >>> + /*
> >>> + * FIXME:
> >>> + * GEN8_SDEUNIT_CLOCK_GATE_DISABLE applies on A0 only.
> >>
> >> We have pci revid macros now. Do you have plans to roll similar ones out
> >> for bxt?
> >
> > Yes. It may be that for BXT we also need to look at the PCI_REVISION_ID
> > field besides PCI_CLASS_REVISION, I still have to figure out the exact
> > mapping. (And also understand the meaning/difference between SOC vs. GT
> > revision IDs).

Ok, the above is red herring. PCI_REVISION_ID is just the 8 low bits of
PCI_CLASS_REVISION, so we can reuse INTEL_REVID as-is.

> I've posted a patch with the Broxton revision ID's from the specs.

It looks ok, but I prefer adding them as a follow-up to this patchset.