Re: [PATCH 10/11] drm/simple-helper: drm_gem_simple_display_pipe_prepare_fb as default

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, May 25, 2021 at 07:48:12PM +0200, Noralf Trønnes wrote:
> > It's tedious to review this all the time, and my audit showed that
> > arcpgu actually forgot to set this.
> >
> > Make this the default and stop worrying.
> >
> > Again I sprinkled WARN_ON_ONCE on top to make sure we don't have
> > strange combinations of hooks: cleanup_fb without prepare_fb doesn't
> > make sense, and since simpler drivers are all new they better be GEM
> > based drivers.
> >
> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> > Cc: Maxime Ripard <mripard@kernel.org>
> > Cc: Thomas Zimmermann <tzimmermann@suse.de>
> > Cc: David Airlie <airlied@linux.ie>
> > Cc: Daniel Vetter <daniel@ffwll.ch>
> > ---
> >  drivers/gpu/drm/drm_simple_kms_helper.c | 12 ++++++++++--
> >  include/drm/drm_simple_kms_helper.h     |  7 +++++--
> >  2 files changed, 15 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c
> b/drivers/gpu/drm/drm_simple_kms_helper.c
> > index 0b095a313c44..1a97571d97d9 100644
> > --- a/drivers/gpu/drm/drm_simple_kms_helper.c
> > +++ b/drivers/gpu/drm/drm_simple_kms_helper.c
> > @@ -9,6 +9,8 @@
> >  #include <drm/drm_atomic.h>
> >  #include <drm/drm_atomic_helper.h>
> >  #include <drm/drm_bridge.h>
> > +#include <drm/drm_drv.h>
> > +#include <drm/drm_gem_atomic_helper.h>
> >  #include <drm/drm_managed.h>
> >  #include <drm/drm_plane_helper.h>
> >  #include <drm/drm_probe_helper.h>
> > @@ -225,8 +227,14 @@ static int drm_simple_kms_plane_prepare_fb(struct
> drm_plane *plane,
> >  	struct drm_simple_display_pipe *pipe;
> >
> >  	pipe = container_of(plane, struct drm_simple_display_pipe, plane);
> > -	if (!pipe->funcs || !pipe->funcs->prepare_fb)
> > -		return 0;
> > +	if (!pipe->funcs || !pipe->funcs->prepare_fb) {
> > +		if (WARN_ON_ONCE(drm_core_check_feature(plane->dev, DRIVER_GEM)))
> 
> Shouldn't this check be inverted? Looks like it warns on GEM drivers.

Ah yes, I'll fix.

> With that considered:
> 
> Acked-by: Noralf Trønnes <noralf@tronnes.org>
> 
> Hopefully this reply will thread correctly, I had to reply from lore (I
> wasn't cc'ed) and I don't know if Thunderbird sets In-Reply-To. I'm not
> subscribed to dri-devel anymore since I'm winding down my Linux work and
> dri-devel is such a high volume list.

Thanks a lot for taking a look, threaded all correctly.
-Daniel

> Noralf
> 
> > +			return 0;
> > +
> > +		WARN_ON_ONCE(pipe->funcs && pipe->funcs->cleanup_fb);
> > +
> > +		return drm_gem_simple_display_pipe_prepare_fb(pipe, state);
> > +	}
> >
> >  	return pipe->funcs->prepare_fb(pipe, state);
> >  }

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch