• Rodrigo Vivi's avatar
    drm/i915: PSR: Remove Low Power HW tracking mask. · 09108b90
    Rodrigo Vivi authored
    By Spec we should only mask memup and hotplug detection
    for hardware tracking cases. However we always masked
    LPSP because with power well always enabled on audio
    PSR was never being activated and residency was always
    zeroed.
    
    Apparently audio driver is tying power well management
    and runtime PM for some reason. But with audio runtime
    PM working or with audio completely out of picture
    we should remove this mask, otherwise we have a high
    risk of miss screen updates as faced by Matthew.
    
    WARNING: With this patch if snd_intel_hda driver is
    running and not releasing power well properly PSR will
    constant Exit and Performance Counter will be 0.
    
    But the best thing of this patch is that with one more
    HW tracking working the risks of missed blank screen
    are minimized at most.
    
    This affects just core platforms where PSR exit are also
    helped by HW tracking: Haswell, Broadwell and Skylake
    for now.
    
    v2: Fix commit message explanation. It has nothing to do
    with runtime PM on i915 as previously advertised.
    
    Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
    Cc: Matthew Garrett <mjg59@srcf.ucam.org>
    Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
    Reviewed-by: default avatarPaulo Zanoni <paulo.r.zanoni@intel.com>
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    09108b90
intel_psr.c 23.5 KB