On Wed, May 27, 2026 at 08:51:29PM +0300, Vitaliy Makkoveev wrote:
> On Wed, May 27, 2026 at 07:27:47PM +0200, Walter Alejandro Iglesias wrote:
> > 
> > I found a function defined in ../drm/drm_fb_helper.c,
> > drm_fb_helper_restore_fbdev_mode_unlocked() which restores the entire
> > fbdev display mode (including size).
> > 
> 
> Thanks, this diff completely fixes my issue. ok mvs@
> 
> > Index: i915_driver.c
> > ===================================================================
> > RCS file: /cvs/src/sys/dev/pci/drm/i915/i915_driver.c,v
> > diff -u -p -u -p -r1.30 i915_driver.c
> > --- i915_driver.c	30 Apr 2026 04:33:06 -0000	1.30
> > +++ i915_driver.c	27 May 2026 13:32:34 -0000
> > @@ -2154,8 +2154,14 @@ inteldrm_burner_cb(void *arg1)
> >  	struct drm_i915_private *dev_priv = arg1;
> >  	struct drm_device *dev = &dev_priv->drm;
> >  	struct drm_fb_helper *helper = dev->fb_helper;
> > +	struct rasops_info *ri = &dev_priv->ro;
> >  
> >  	drm_fb_helper_blank(dev_priv->burner_fblank, helper->info);
> > +
> > +	if (dev_priv->burner_fblank == FB_BLANK_UNBLANK) {
> > +		drm_fb_helper_restore_fbdev_mode_unlocked(helper);
> > +		rasops_show_screen(ri, ri->ri_active, 0, NULL, NULL);
> > +	}
> >  }
> >  
> >  int


To confirm your Alder Lake suffers from two different issues.  I'd like
to know what happens if we remove rasops_show_screen from the diff.
This should avoid the Alder Lake half-line on top but not the ghosting.


Index: i915_driver.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/drm/i915/i915_driver.c,v
diff -u -p -u -p -r1.30 i915_driver.c
--- i915_driver.c	30 Apr 2026 04:33:06 -0000	1.30
+++ i915_driver.c	28 May 2026 10:41:46 -0000
@@ -2156,6 +2156,8 @@ inteldrm_burner_cb(void *arg1)
 	struct drm_fb_helper *helper = dev->fb_helper;
 
 	drm_fb_helper_blank(dev_priv->burner_fblank, helper->info);
+	if (dev_priv->burner_fblank == FB_BLANK_UNBLANK && helper)
+		drm_fb_helper_restore_fbdev_mode_unlocked(helper);
 }
 
 int




-- 
Walter