Re: [RFC 13/28] drm/i915: Convert i915_gem_init_hw to intel_gt

Chris Wilson
2019-06-14T09:41:52Z

Quoting Tvrtko Ursulin (2019-06-14 10:34:06)
>
> On 13/06/2019 17:30, Chris Wilson wrote:
> > Quoting Tvrtko Ursulin (2019-06-13 17:11:43)
> >>
> >> On 13/06/2019 14:59, Chris Wilson wrote:
> >>> Quoting Tvrtko Ursulin (2019-06-13 14:35:24)
> >>>> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> >>>> index e54cd30534dc..b6f450e782e7 100644
> >>>> --- a/drivers/gpu/drm/i915/i915_gem.c
> >>>> +++ b/drivers/gpu/drm/i915/i915_gem.c
> >>>> @@ -1234,28 +1234,32 @@ static void init_unused_rings(struct intel_gt *gt)
> >>>> }
> >>>> }
> >>>>
> >>>> -int i915_gem_init_hw(struct drm_i915_private *dev_priv)
> >>>> +static int init_hw(struct intel_gt *gt)
> >>>> {
> >>>> + struct drm_i915_private *i915 = gt->i915;
> >>>> + struct intel_uncore *uncore = gt->uncore;
> >>>> int ret;
> >>>>
> >>>> - dev_priv->gt.last_init_time = ktime_get();
> >>>> + gt->last_init_time = ktime_get();
> >>>>
> >>>> /* Double layer security blanket, see i915_gem_init() */
> >>>> - intel_uncore_forcewake_get(&dev_priv->uncore, FORCEWAKE_ALL);
> >>>> + intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
> >>>>
> >>>> - if (HAS_EDRAM(dev_priv) && INTEL_GEN(dev_priv) < 9)
> >>>> - I915_WRITE(HSW_IDICR, I915_READ(HSW_IDICR) | IDIHASHMSK(0xf));
> >>>> + if (HAS_EDRAM(i915) && INTEL_GEN(i915) < 9)
> >>>> + intel_uncore_rmw(uncore, HSW_IDICR, 0, IDIHASHMSK(0xf));
> >>>>
> >>>> - if (IS_HASWELL(dev_priv))
> >>>> - I915_WRITE(MI_PREDICATE_RESULT_2, IS_HSW_GT3(dev_priv) ?
> >>>> - LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED);
> >>>> + if (IS_HASWELL(i915))
> >>>> + intel_uncore_write(uncore,
> >>>> + MI_PREDICATE_RESULT_2,
> >>>> + IS_HSW_GT3(i915) ?
> >>>> + LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED);
> >>>>
> >>>> /* Apply the GT workarounds... */
> >>>> - intel_gt_apply_workarounds(&dev_priv->gt);
> >>>> + intel_gt_apply_workarounds(gt);
> >>>
> >>> Would it be worth moving the above mmio into workarounds? Whilst you are
> >>> doing some spring cleaning :)
> >>
> >> To GT workarounds? Are the above two workarounds? Do they have an
> >> official designation?
> >
> > To intel_gt_workarounds_apply, I'm sure you can find something ;)
>
> Having looked up the docs for HSW_IDCR and MI_PREDICATE_RESULT_2,
> neither of the programming looks like workarounds but normal device init
> to me. As such I don't see how it would be appropriate to move them into
> workarounds.

Where they are is definitely not where they should be. I'm sure I've
complained about this since they were put there. And normal device init ==
workarounds, does it not? It is just a list of registers that need to be
programmed to default values, where those default values were decided
upon after the fact.
-Chris