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
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