]> git.itanic.dy.fi Git - linux-stable/commit
drm/i915/display/adlp: Optimize PSR2 power-savings in corner cases
authorJosé Roberto de Souza <jose.souza@intel.com>
Thu, 30 Sep 2021 00:14:06 +0000 (17:14 -0700)
committerJosé Roberto de Souza <jose.souza@intel.com>
Thu, 30 Sep 2021 22:04:45 +0000 (15:04 -0700)
commit1163649a047995c77527023f192d00ae1971965b
tree9b130b8a5bad0d4a5f25ff29de34f915988e08b2
parentef39826c12b409010b8fb29fc47e2586cd2635ee
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
drivers/gpu/drm/i915/display/intel_psr.c