[PATCH i915 v3 1/2] i915: wait for fences in mmio_flip()

[Daniel Stone]

Hi,

On 13 November 2015 at 10:08, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On Thu, Nov 12, 2015 at 05:49:28PM -0800, Alex Goins wrote:
>>  static const uint32_t i8xx_primary_formats[] = {
>> @@ -11170,10 +11172,19 @@ static void ilk_do_mmio_flip(struct intel_crtc *intel_crtc)
>>  static void intel_do_mmio_flip(struct intel_crtc *intel_crtc)
>>  {
>>       struct drm_device *dev = intel_crtc->base.dev;
>> +     struct drm_i915_gem_object *pending_flip_obj =
>> +             intel_crtc->unpin_work->pending_flip_obj;
>>       u32 start_vbl_count;
>>
>>       intel_mark_page_flip_active(intel_crtc);
>>
>> +     /* For framebuffer backed by dmabuf, wait for fence */
>> +     if (pending_flip_obj->base.dma_buf) {
>> +             reservation_object_wait_timeout_rcu(
>> +                     pending_flip_obj->base.dma_buf->resv,
>> +                     true, false, msecs_to_jiffies(96));
>> +     }
>
> This wait should be prior to marking the flip as waiting for the
> flip-completion interrupt. My personal preference (aside from putting
> this next to the other wait) would to have been to use crtc->primary->fb
> to match the do_mmip_flips funcs (I expect that we will eliminate the
> pending_flip_obj in the near future).

No, don't use crtc->primary->fb for anything.

Cheers,
Daniel