• Lyude's avatar
    drm/i915/gen6+: Interpret mailbox error flags · 87660502
    Lyude authored
    In order to add proper support for the SAGV, we need to be able to know
    what the cause of a failure to change the SAGV through the pcode mailbox
    was. The reasoning for this is that some very early pre-release Skylake
    machines don't actually allow you to control the SAGV on them, and
    indicate an invalid mailbox command was sent.
    
    This also might come in handy in the future for debugging.
    
    Changes since v1:
     - Add functions for interpreting gen6 mailbox error codes along with
       gen7+ error codes, and actually interpret those codes properly
     - Renamed patch to reflect new behavior
    Signed-off-by: default avatarLyude <cpaul@redhat.com>
    Cc: Matt Roper <matthew.d.roper@intel.com>
    Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
    Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
    Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
    Link: http://patchwork.freedesktop.org/patch/msgid/1471463761-26796-2-git-send-email-cpaul@redhat.com
    [mlankhorst: -ENOSYS -> -ENXIO for checkpatch]
    87660502
intel_pm.c 222 KB