On Sat, Sep 13, 2014 at 05:20:10PM +0100, Chris Wilson wrote:
> On Fri, Sep 12, 2014 at 08:53:34PM +0300, ville.syrjala@xxxxxxxxxxxxxxx wrote:
> > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> >
> > Only write CURBASE when something about the cursor changed. Also
> > eliminate the unnecessary posting read after writing CURCNTR.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/intel_display.c | 10 ++++++----
> > 1 file changed, 6 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > index 82c0ad1..60c1aa4 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -8322,16 +8322,18 @@ static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base)
> > cntl |= CURSOR_PIPE_CSC_ENABLE;
> > }
> >
> > - if (intel_crtc->cursor_cntl != cntl) {
> > + if (intel_crtc->cursor_cntl != cntl)
> > I915_WRITE(CURCNTR(pipe), cntl);
> > - POSTING_READ(CURCNTR(pipe));
> > - intel_crtc->cursor_cntl = cntl;
> > - }
> > +
> > + if (intel_crtc->cursor_cntl == cntl &&
> > + intel_crtc->cursor_base == base)
> > + return;
>
> I'd vote for doing this first and then
>
> I915_WRITE(CURCNTR(pipe), cntl);
>
> unconditionally along with the CURBASE flush.
So you want to write all the cursor registers unconditionally when
anything changes? Would work for CURCNTR, but it would also make
CUR_FBC_CTL stand out like a sore thumb since it can't be written
uncoditionally.
>
> > /* and commit changes on next vblank */
> > I915_WRITE(CURBASE(pipe), base);
> > POSTING_READ(CURBASE(pipe));
> >
> > + intel_crtc->cursor_cntl = cntl;
> > intel_crtc->cursor_base = base;
> > }
>
> --
> Chris Wilson, Intel Open Source Technology Centre
--
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
