Op 06-08-16 om 02:07 schreef Lyude: > From: Matt Roper <matthew.d.roper at intel.com> > > When we write watermark values to the hardware, those values are stored > in dev_priv->wm.skl_hw. However with recent watermark changes, the > results structure we're copying from only contains valid watermark and > DDB values for the pipes that are actually changing; the values for > other pipes remain 0. Thus a blind copy of the entire skl_wm_values > structure will clobber the values for unchanged pipes...we need to be > more selective and only copy over the values for the changing pipes. > > This mistake was hidden until recently due to another bug that caused us > to erroneously re-calculate watermarks for all active pipes rather than > changing pipes. Only when that bug was fixed was the impact of this bug > discovered (e.g., modesets failing with "Requested display configuration > exceeds system watermark limitations" messages and leaving watermarks > non-functional, even ones initiated by intel_fbdev_restore_mode). > > Changes since v1: > - Add a function for copying a pipe's wm values > (skl_copy_wm_for_pipe()) so we can reuse this later > > Fixes: 734fa01f3a17 ("drm/i915/gen9: Calculate watermarks during atomic > 'check' (v2)") > Fixes: 9b6130227495 ("drm/i915/gen9: Re-allocate DDB only for changed pipes") > Signed-off-by: Matt Roper <matthew.d.roper at intel.com> > Signed-off-by: Lyude <cpaul at redhat.com> > Reviewed-by: Matt Roper <matthew.d.roper at intel.com> > Cc: stable at vger.kernel.org > Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com> > Cc: Daniel Vetter <daniel.vetter at intel.com> > Cc: Radhakrishna Sripada <radhakrishna.sripada at intel.com> > Cc: Hans de Goede <hdegoede at redhat.com>
Testcase: kms_cursor_legacy Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>