[Intel-gfx] [PATCH v8 4/8] drm/i915: Do not call drm_crtc_arm_vblank_event in async flips

[Karthik B S]

On 9/15/2020 7:37 PM, Ville Syrjälä wrote:
> On Mon, Sep 14, 2020 at 11:26:29AM +0530, Karthik B S wrote:
>> Since the flip done event will be sent in the flip_done_handler,
>> no need to add the event to the list and delay it for later.
>>
>> v2: -Moved the async check above vblank_get as it
>>       was causing issues for PSR.
>>
>> v3: -No need to wait for vblank to pass, as this wait was causing a
>>       16ms delay once every few flips.
>>
>> v4: -Rebased.
>>
>> v5: -Rebased.
>>
>> v6: -Rebased.
>>
>> v7: -No need of irq disable if we are not doing vblank evade. (Ville)
>>
>> v8: -Rebased.
>>
>> Signed-off-by: Karthik B S <karthik.b.s at intel.com>
>> Signed-off-by: Vandita Kulkarni <vandita.kulkarni at intel.com>
>> ---
>>   drivers/gpu/drm/i915/display/intel_sprite.c | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c
>> index 5ac0dbf0e03d..f0c89418d2e1 100644
>> --- a/drivers/gpu/drm/i915/display/intel_sprite.c
>> +++ b/drivers/gpu/drm/i915/display/intel_sprite.c
>> @@ -93,6 +93,9 @@ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state)
>>   	DEFINE_WAIT(wait);
>>   	u32 psr_status;
>>   
>> +	if (new_crtc_state->uapi.async_flip)
>> +		return;
>> +
>>   	vblank_start = adjusted_mode->crtc_vblank_start;
>>   	if (adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
>>   		vblank_start = DIV_ROUND_UP(vblank_start, 2);
>> @@ -202,6 +205,9 @@ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
>>   
>>   	trace_intel_pipe_update_end(crtc, end_vbl_count, scanline_end);
>>   
>> +	if (new_crtc_state->uapi.async_flip)
>> +		return;
> 
> The pipe update tracepoints will be inconsistent if you put this here.
> I guess we don't really need the pipe update tracepoints for async
> flips. We might want to add a separate tracepoint for async flip itself,
> or perhaps convey the sync vs. async information via the current
> plane update tracepoint.
> 

Thanks for the review.
Sure, I'll move this before the tracepoint.

> With this moved to before the tracepoint
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 

Thanks for the RB.

Thanks,
Karthik.B.S
>> +
>>   	/* We're still in the vblank-evade critical section, this can't race.
>>   	 * Would be slightly nice to just grab the vblank count and arm the
>>   	 * event outside of the critical section - the spinlock might spin for a
>> -- 
>> 2.22.0
>