Re: [Intel-gfx] [PATCH] drm/i915: flush cursors harder

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Mon, Nov 04, 2013 at 05:34:41PM +0100, Daniel Vetter wrote:
> On Mon, Nov 04, 2013 at 06:02:24PM +0200, Ville Syrjälä wrote:
> > On Mon, Nov 04, 2013 at 08:13:45AM +0100, Daniel Vetter wrote:
> > > Apparently they need the same treatment as primary planes. This fixes
> > > modesetting failures because of stuck cursors (!) on Thomas' i830M
> > > machine.
> > 
> > What treatment? Primary planes don't need any extra posting reads AFAIK.
> 
> If you look at flush_primary_plane it's definitely there. So I've copied
> it over (it's just a real I915_READ, not a posting one).

The regular read is there just so that we don't modify the surface
base address. We should be able to replace the read w/ recomputing
the address.

> 
> > 
> > > 
> > > I've figured while at it I'll also roll it out for the ivb 3 pipe
> > > version of this function. I didn't do this for i845/i865 since Bspec
> > > says the update mechanism works differently, and there's some
> > > additional rules about what can be updated in which order.
> > > 
> > > Tested-by: Thomas Richter <thor@math.tu-berlin.de>
> > 
> > I didn't see an explicit note from Thomas saying that he tested it.
> 
> It's burried somewhere in the thread, but he said that with the 2 earlier
> dvo patches + this one here the lvds-only use-case now works well. Before
> that he had issues with the display just showing a cursor and the kernel
> complaining about the cursor being stuck in the enabled position when
> trying to re-enable it.

From the mails, I couldn't figure out if he tried them all or just the
two patches you posted earlier.

> -Daniel
> 
> > 
> > > Cc: stable@vger.kernel.org
> > > Cc:  Thomas Richter <thor@math.tu-berlin.de>
> > > Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > ---
> > >  drivers/gpu/drm/i915/intel_display.c | 4 ++++
> > >  1 file changed, 4 insertions(+)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > > index f34252d134b6..04d2699f51b4 100644
> > > --- a/drivers/gpu/drm/i915/intel_display.c
> > > +++ b/drivers/gpu/drm/i915/intel_display.c
> > > @@ -7123,7 +7123,9 @@ static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base)
> > >  		intel_crtc->cursor_visible = visible;
> > >  	}
> > >  	/* and commit changes on next vblank */
> > > +	POSTING_READ(CURCNTR(pipe));
> > >  	I915_WRITE(CURBASE(pipe), base);
> > > +	POSTING_READ(CURBASE(pipe));
> > >  }
> > >  
> > >  static void ivb_update_cursor(struct drm_crtc *crtc, u32 base)
> > > @@ -7152,7 +7154,9 @@ static void ivb_update_cursor(struct drm_crtc *crtc, u32 base)
> > >  		intel_crtc->cursor_visible = visible;
> > >  	}
> > >  	/* and commit changes on next vblank */
> > > +	POSTING_READ(CURCNTR_IVB(pipe));
> > >  	I915_WRITE(CURBASE_IVB(pipe), base);
> > > +	POSTING_READ(CURBASE_IVB(pipe));
> > >  }
> > >  
> > >  /* If no-part of the cursor is visible on the framebuffer, then the GPU may hang... */
> > > -- 
> > > 1.8.4.rc3
> > > 
> > > _______________________________________________
> > > Intel-gfx mailing list
> > > Intel-gfx@lists.freedesktop.org
> > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > 
> > -- 
> > Ville Syrjälä
> > Intel OTC
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

-- 
Ville Syrjälä
Intel OTC