| Message ID | 20200213140412.32697-4-stanislav.lisovskiy@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix modeset transitions related to DBuf | expand |
On Thu, Feb 13, 2020 at 04:04:12PM +0200, Stanislav Lisovskiy wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > Currently when we load the driver we set distrust_bios_wm=true, which > will cause active_pipe_changes to get flagged even when we're not > toggling any pipes on/off. The reason being that we want to fully > redistribute the dbuf among the active pipes and ignore whatever > state the firmware left behind. > > Unfortunately when the code flags active_pipe_changes it doesn't > set state->modeset to true, which means the hardware dbuf state > won't actually get updated. Hence the hardware and software > states go out of sync, which can result in planes trying to use a > disabled dbuf slice. Suprisingly that only seems to corrupt the > display rather than making the whole display engine keel over. > > Let's fix this for now by flagging state->modeset whenever > distrust_bios_wm is set. > > Eventually we'll likely want to rip out all of this mess and > introduce proper statye tracking for dbuf. But that requires > more work. Toss in a FIXME to that effect. > > Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> > Fixes: ff2cd8635e41 ("drm/i915: Correctly map DBUF slices to pipes") > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> Reviewed-by: Matt Roper <matthew.d.roper@intel.com> > --- > drivers/gpu/drm/i915/display/intel_display.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index 1e3f2cc27db8..df47b2fdfa38 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -15027,6 +15027,20 @@ static int intel_atomic_check(struct drm_device *dev, > if (new_cdclk_state && new_cdclk_state->force_min_cdclk_changed) > any_ms = true; > > + /* > + * distrust_bios_wm will force a full dbuf recomputation > + * but the hardware state will only get updated accordingly > + * if state->modeset==true. Hence distrust_bios_wm==true && > + * state->modeset==false is an invalid combination which > + * would cause the hardware and software dbuf state to get > + * out of sync. We must prevent that. > + * > + * FIXME clean up this mess and introduce better > + * state tracking for dbuf. > + */ > + if (dev_priv->wm.distrust_bios_wm) > + any_ms = true; > + > if (any_ms) { > ret = intel_modeset_checks(state); > if (ret) > -- > 2.24.1.485.gad05a3d8e5 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c index 1e3f2cc27db8..df47b2fdfa38 100644 --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -15027,6 +15027,20 @@ static int intel_atomic_check(struct drm_device *dev, if (new_cdclk_state && new_cdclk_state->force_min_cdclk_changed) any_ms = true; + /* + * distrust_bios_wm will force a full dbuf recomputation + * but the hardware state will only get updated accordingly + * if state->modeset==true. Hence distrust_bios_wm==true && + * state->modeset==false is an invalid combination which + * would cause the hardware and software dbuf state to get + * out of sync. We must prevent that. + * + * FIXME clean up this mess and introduce better + * state tracking for dbuf. + */ + if (dev_priv->wm.distrust_bios_wm) + any_ms = true; + if (any_ms) { ret = intel_modeset_checks(state); if (ret)