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

Tvrtko Ursulin
2019-06-14T15:00:31Z

On 14/06/2019 10:41, Chris Wilson wrote:
> 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.

Well we could argue.. :) I see stuff in intel_workarounds as having
WaXXXX names, give or take. So I prefer to leave this here for now.

Regards,

Tvrtko