On Mon, Jul 17, 2017 at 12:42:18PM +0200, Paul Menzel wrote: > Dear Ville, > > > On 07/14/17 17:52, ville.syrjala@xxxxxxxxxxxxxxx wrote: > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > > Turns out that just writing CURPOS isn't sufficient to move the cursor > > on some platforms. My 830 works just fine, but eg. 945 and PNV don't. > > On those platforms we need to arm even the CURPOS update with a > > CURBASE write. > > > > Even worse, a write to any of the cursor register apart from CURBASE > > will cancel an already pending cursor update. So if we have armed a > > CURCNTR/CURBASE update, a subsequent CURPOS write prior to vblank > > would cancel that armed update. Thus we're left with a cursor that > > doesn't appear to move, or even change shape. > > > > Fix the problem by always performing the CURBASE write after a > > CURPOS write. Bspec is somewhat unclear which platforms actually > > require this CURBASE write and which don't. So to keep it simple > > and to make sure we really fix the problem across all supported > > devices, let's just perform the CURBASE write unconditionally. > > > > Cc: Paul Menzel <pmenzel@xxxxxxxxxxxxx> > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101790 > > Fixes: 75343a44c901 ("drm/i915: Drop useless posting reads from cursor commit") > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_display.c | 12 +++++++++++- > > 1 file changed, 11 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > > index 2144adc5b1d5..460bd942fcb7 100644 > > --- a/drivers/gpu/drm/i915/intel_display.c > > +++ b/drivers/gpu/drm/i915/intel_display.c > > @@ -9555,7 +9555,16 @@ static void i9xx_update_cursor(struct intel_plane *plane, > > * On some platforms writing CURCNTR first will also > > * cause CURPOS to be armed by the CURBASE write. > > * Without the CURCNTR write the CURPOS write would > > - * arm itself. > > + * arm itself. Thus we always start the full update > > + * with a CURCNTR write. > > + * > > + * On other platforms CURPOS always requires the > > + * CURBASE write to arm the update. Additonally > > + * a write to any of the cursor register will cancel > > + * an already armed cursor update. Thus leaving out > > + * the CURBASE write after CURPOS could lead to a > > + * cursor that doesn't appear to move, or even change > > + * shape. Thus we always write CURBASE. > > * > > * CURCNTR and CUR_FBC_CTL are always > > * armed by the CURBASE write only. > > @@ -9574,6 +9583,7 @@ static void i9xx_update_cursor(struct intel_plane *plane, > > plane->cursor.cntl = cntl; > > } else { > > I915_WRITE_FW(CURPOS(pipe), pos); > > + I915_WRITE_FW(CURBASE(pipe), base); > > } > > POSTING_READ_FW(CURBASE(pipe)); > > Tested-by: Paul Menzel <paulepanter@xxxxxxxxxxxxxxxxxxxxx> Since Ville is on vacation I applied this. -Daniel > > I created two more bugs for an issue with pasting text with the middle mouse > button [1], and failing *kms_cursor_crc* tests [2]. > > > Kind regards, > > Paul Menzel > > > [1] https://bugs.freedesktop.org/show_bug.cgi?id=101819 > [2] https://bugs.freedesktop.org/show_bug.cgi?id=101817 > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
