[Intel-gfx] [PATCH 14/15] drm/i915: Track frontbuffer invalidation/flushing

[Daniel Vetter]

On Tue, Jun 17, 2014 at 07:41:48AM +0100, Chris Wilson wrote:
> On Mon, Jun 16, 2014 at 07:51:34PM +0200, Daniel Vetter wrote:
> > diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
> > index 27975c3e21c5..12276c39d14d 100644
> > --- a/drivers/gpu/drm/i915/intel_fbdev.c
> > +++ b/drivers/gpu/drm/i915/intel_fbdev.c
> > @@ -43,10 +43,26 @@
> >  #include <drm/i915_drm.h>
> >  #include "i915_drv.h"
> >  
> > +static int intel_fbdev_set_par(struct fb_info *info)
> > +{
> > +	struct drm_fb_helper *fb_helper = info->par;
> > +	struct intel_fbdev *ifbdev =
> > +		container_of(fb_helper, struct intel_fbdev, helper);
> > +	int ret;
> > +
> > +	ret = drm_fb_helper_set_par(info);
> > +
> > +	if (ret == 0)
> > +		ret = i915_gem_object_set_to_gtt_domain(ifbdev->fb->obj,
> > +							true);
> > +
> > +	return ret;
> > +}
> 
> Ah, I had missed you added this. Yes, this is what I had in mind for
> fixing fbcon. However, this is worth splitting out into a separate path
> as this is about to get hairy!
> 
> ret = drm_fb_helper_set_par(info)
> if (ret) return ret;
> 
>  /* Invalidate the fb for all further writes whilst on the console */
>  if (!in_atomic() && mutex_trylock(&dev->struct_mutex)) {
>    ret = i915_gem_object_set_tp_gtt_domain(obj, true);
>    mutex_unlock(&dev->srtuct_mutex);
>   }
>  return ret;

We already have ridiculous amounts of not trylocked state in set_par, so
doing this won't help really. And fixing up the emergency console logic is
imo out of scope for this ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch