On Wed, May 29, 2024 at 04:03:20AM +0300, Laurent Pinchart wrote:
> Hi Geert,
>
> Thank you for the patch.
>
> On Mon, May 27, 2024 at 03:34:48PM +0200, Geert Uytterhoeven wrote:
> > Add support for the drm_panic module, which displays a message on
> > the screen when a kernel panic occurs.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > ---
> > Tested on Armadillo-800-EVA.
> > ---
> > drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c | 14 +++++++++++++-
> > 1 file changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c b/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
> > index 07ad17d24294d5e6..9d166ab2af8bd231 100644
> > --- a/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
> > +++ b/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
> > @@ -273,6 +273,13 @@ static const struct drm_plane_helper_funcs shmob_drm_plane_helper_funcs = {
> > .atomic_disable = shmob_drm_plane_atomic_disable,
> > };
> >
> > +static const struct drm_plane_helper_funcs shmob_drm_primary_plane_helper_funcs = {
> > + .atomic_check = shmob_drm_plane_atomic_check,
> > + .atomic_update = shmob_drm_plane_atomic_update,
> > + .atomic_disable = shmob_drm_plane_atomic_disable,
> > + .get_scanout_buffer = drm_fb_dma_get_scanout_buffer,
> > +};
> > +
> > static const struct drm_plane_funcs shmob_drm_plane_funcs = {
> > .update_plane = drm_atomic_helper_update_plane,
> > .disable_plane = drm_atomic_helper_disable_plane,
> > @@ -310,7 +317,12 @@ struct drm_plane *shmob_drm_plane_create(struct shmob_drm_device *sdev,
> >
> > splane->index = index;
> >
> > - drm_plane_helper_add(&splane->base, &shmob_drm_plane_helper_funcs);
> > + if (type == DRM_PLANE_TYPE_PRIMARY)
> > + drm_plane_helper_add(&splane->base,
> > + &shmob_drm_primary_plane_helper_funcs);
> > + else
> > + drm_plane_helper_add(&splane->base,
> > + &shmob_drm_plane_helper_funcs);
>
> It's not very nice to have to provide different operations for the
> primary and overlay planes. The documentation of
> drm_fb_dma_get_scanout_buffer() states
>
> * @plane: DRM primary plane
>
> If the intent is that only primary planes will be used to display the
> panic message, shouldn't drm_panic_register() skip overlay planes ? It
> would simplify drivers.
What about the drivers where all the planes are actually universal?
In such a case the planes registered as primary can easily get replaced
by 'overlay' planes.
>
> >
> > return &splane->base;
> > }
>
> --
> Regards,
>
> Laurent Pinchart
--
With best wishes
Dmitry
