[Intel-gfx] [PATCH v2 6/9] drm/i915/display/adlp: Optimize PSR2 power-savings in corner cases

[José Roberto de Souza]

The Wa_14014971508 is required to fix scanout when a feature that i915
do not support is enabled and this feature is not planned to be enabled
for adlp.

Keeping this workaround enabled can badly hurt power-savings when
a full frame fetch is required(see psr2_sel_fetch_plane_state_supported()
and psr2_sel_fetch_pipe_state_supported()).

Here a example that could badly hurt power-savings, userspace does
a page flip to a rotated plane, so CONTINUOS_FULL_FRAME set.
But then for a whole 30 seconds nothing in the screen requires updates
but because CONTINUOS_FULL_FRAME is set, it will not go into DC5/DC6.

Reverting Wa_14014971508 fixes that, as only a single frame will be
sent and then display can go to DC5/DC6 for those 30 seconds of
idleness.

BSpec: 54369
Cc: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_psr.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index e8af39591dfea..b37f123fe0c97 100644
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -1499,15 +1499,10 @@ static void psr2_man_trk_ctl_calc(struct intel_crtc_state *crtc_state,
 
 	if (full_update) {
 		/*
-		 * Wa_14014971508:adlp
-		 * SINGLE_FULL_FRAME bit is not hold in register so can not be
-		 * restored by DMC, so using CONTINUOS_FULL_FRAME to mimic that
+		 * Not applying Wa_14014971508:adlp as we do not support the
+		 * feature that requires this workaround.
 		 */
-		if (IS_ALDERLAKE_P(dev_priv))
-			val |= ADLP_PSR2_MAN_TRK_CTL_SF_CONTINUOS_FULL_FRAME;
-		else
-			val |= PSR2_MAN_TRK_CTL_SF_SINGLE_FULL_FRAME;
-
+		val |= man_trk_ctl_single_full_frame_bit_get(dev_priv);
 		goto exit;
 	}
 
-- 
2.33.0