[Intel-gfx] [PATCH v2 4/4] drm/i915: Calculate vlv/chv intermediate watermarks correctly, v2.

[Maarten Lankhorst]

Op 03-05-17 om 15:45 schreef Ville Syrjälä:
> On Mon, May 01, 2017 at 03:34:34PM +0200, Maarten Lankhorst wrote:
>> The watermarks it should calculate against are the old optimal watermarks.
>> The currently active crtc watermarks are pure fiction, and are invalid in
>> case of a nonblocking modeset, page flip enabling/disabling planes or any
>> other reason.
>>
>> When the crtc is disabled or during a modeset the intermediate watermarks
>> don't need to be programmed separately, and could be directly assigned
>> to the optimal watermarks.
>>
>> Also rename crtc_state to new_crtc_state, to distinguish it from the old state.
>>
>> Changes since v1:
>> - Use intel_atomic_get_old_crtc_state. (ville)
>>
>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>> ---
>>  drivers/gpu/drm/i915/intel_pm.c | 20 ++++++++++++++------
>>  1 file changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>> index 0f344b1fff45..a09396ee1f3d 100644
>> --- a/drivers/gpu/drm/i915/intel_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>> @@ -1458,16 +1458,24 @@ static void vlv_atomic_update_fifo(struct intel_atomic_state *state,
>>  
>>  static int vlv_compute_intermediate_wm(struct drm_device *dev,
>>  				       struct intel_crtc *crtc,
>> -				       struct intel_crtc_state *crtc_state)
>> +				       struct intel_crtc_state *new_crtc_state)
>>  {
>> -	struct vlv_wm_state *intermediate = &crtc_state->wm.vlv.intermediate;
>> -	const struct vlv_wm_state *optimal = &crtc_state->wm.vlv.optimal;
>> -	const struct vlv_wm_state *active = &crtc->wm.active.vlv;
>> +	struct vlv_wm_state *intermediate = &new_crtc_state->wm.vlv.intermediate;
>> +	const struct vlv_wm_state *optimal = &new_crtc_state->wm.vlv.optimal;
>> +	const struct intel_crtc_state *old_crtc_state =
>> +		intel_atomic_get_old_crtc_state(new_crtc_state->base.state, crtc);
>> +	const struct vlv_wm_state *active = &old_crtc_state->wm.vlv.optimal;
>>  	int level;
>>  
>> +	if (!new_crtc_state->base.active || drm_atomic_crtc_needs_modeset(&new_crtc_state->base)) {
>> +		*intermediate = *optimal;
>> +
>> +		return 0;
>> +	}
>> +
>>  	intermediate->num_levels = min(optimal->num_levels, active->num_levels);
>>  	intermediate->cxsr = optimal->cxsr && active->cxsr &&
>> -		!crtc_state->disable_cxsr;
>> +		!new_crtc_state->disable_cxsr;
> We need to consider disable_cxsr even in the modeset case.
Why is this? crtc_state->disable_cxsr is set if any plane is part of the crtc during modeset, so it's disabled during modeset already.

~Maarten