[Intel-gfx] [PATCH 1/2] drm/i915: Teach record_defaults to operate on the intel_gt

[Tvrtko Ursulin]

On 22/10/2019 14:56, Chris Wilson wrote:
> Quoting Tvrtko Ursulin (2019-10-22 14:40:42)
>>
>> On 22/10/2019 14:02, Chris Wilson wrote:
>>> Again we wish to operate on the engines, which are owned by the
>>> intel_gt. As such it is easier, and much more consistent, to pass the
>>> intel_gt parameter.
>>>
>>> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
>>> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>>> ---
>>>    drivers/gpu/drm/i915/i915_gem.c | 14 ++++++++------
>>>    1 file changed, 8 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
>>> index ca64a0c9b762..b882988056bd 100644
>>> --- a/drivers/gpu/drm/i915/i915_gem.c
>>> +++ b/drivers/gpu/drm/i915/i915_gem.c
>>> @@ -48,6 +48,7 @@
>>>    #include "gt/intel_engine_user.h"
>>>    #include "gt/intel_gt.h"
>>>    #include "gt/intel_gt_pm.h"
>>> +#include "gt/intel_gt_requests.h"
>>>    #include "gt/intel_mocs.h"
>>>    #include "gt/intel_reset.h"
>>>    #include "gt/intel_renderstate.h"
>>> @@ -1072,7 +1073,7 @@ void i915_gem_sanitize(struct drm_i915_private *i915)
>>>        intel_runtime_pm_put(&i915->runtime_pm, wakeref);
>>>    }
>>>    
>>> -static int __intel_engines_record_defaults(struct drm_i915_private *i915)
>>> +static int __intel_engines_record_defaults(struct intel_gt *gt)
>>>    {
>>>        struct i915_request *requests[I915_NUM_ENGINES] = {};
>>>        struct intel_engine_cs *engine;
>>> @@ -1088,7 +1089,7 @@ static int __intel_engines_record_defaults(struct drm_i915_private *i915)
>>>         * from the same default HW values.
>>>         */
>>>    
>>> -     for_each_engine(engine, i915, id) {
>>> +     for_each_engine(engine, gt, id) {
>>>                struct intel_context *ce;
>>>                struct i915_request *rq;
>>>    
>>> @@ -1096,7 +1097,8 @@ static int __intel_engines_record_defaults(struct drm_i915_private *i915)
>>>                GEM_BUG_ON(!engine->kernel_context);
>>>                engine->serial++; /* force the kernel context switch */
>>>    
>>> -             ce = intel_context_create(i915->kernel_context, engine);
>>> +             ce = intel_context_create(engine->kernel_context->gem_context,
>>> +                                       engine);
>>>                if (IS_ERR(ce)) {
>>>                        err = PTR_ERR(ce);
>>>                        goto out;
>>> @@ -1125,7 +1127,7 @@ static int __intel_engines_record_defaults(struct drm_i915_private *i915)
>>>        }
>>>    
>>>        /* Flush the default context image to memory, and enable powersaving. */
>>> -     if (!i915_gem_load_power_context(i915)) {
>>> +     if (intel_gt_wait_for_idle(gt, I915_GEM_IDLE_TIMEOUT) == -ETIME) {
>>
>> What are the plans for i915_gem_load_power_context? It does a little bit
>> extra. But also becomes confined to i915_gem_pm.c if not needed here any
>> more so could be unexported.
> 
> It's to be subsumed entirely onto the gt. On resume, we simply call
> intel_gt_resume() which does the power saving setup and ensures we have
> a kernel_context primed. I'm still waiting on Andi's overhaul of GT
> powersaving to land before pulling the plug.

Why it is bad, or not needed, to call intel_gt_pm_wait_for_idle at this 
point?

Regards,

Tvrtko