Re: [PATCH 14/15] drm/i915: Track frontbuffer invalidation/flushing

Daniel Vetter
2014-06-17T07:32:54Z

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