drm/i915/display/adlp: Optimize PSR2 power-savings in corner cases

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@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930001409.254817-6-jose.souza@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index eddf4138b6a88f0948a9023132739faf99ad9851..05b9b103a98f99b78d38a6b61a0d1230789099dc 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -1503,15 +1503,10 @@ 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;
        }