Re: [Intel-gfx] [PATCH 12/15] drm/simple-helper: drm_gem_simple_display_pipe_prepare_fb as default

Sam Ravnborg
2021-06-22T19:16:02Z

Hi Daniel,

On Tue, Jun 22, 2021 at 06:55:08PM +0200, Daniel Vetter 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.
>
> v2: Warn and bail when it's _not_ a GEM driver (Noralf)
>
> Cc: Noralf Trønnes <noralf@tronnes.org>
> Acked-by: Noralf Trønnes <noralf@tronnes.org>
> 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..735f4f34bcc4 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)))
> + 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);
> }
> diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
> index ef9944e9c5fc..363a9a8c3587 100644
> --- a/include/drm/drm_simple_kms_helper.h
> +++ b/include/drm/drm_simple_kms_helper.h
> @@ -116,8 +116,11 @@ struct drm_simple_display_pipe_funcs {
> * the documentation for the &drm_plane_helper_funcs.prepare_fb hook for
> * more details.
> *
> - * Drivers which always have their buffers pinned should use
> - * drm_gem_simple_display_pipe_prepare_fb() for this hook.
> + * For GEM drivers who neither have a @prepare_fb not @cleanup_fb hook
> + * set drm_gem_simple_display_pipe_prepare_fb() is called automatically
> + * to implement this.
Same comments like before.

Sam

* Other drivers which need additional plane
> + * processing can call drm_gem_simple_display_pipe_prepare_fb() from
> + * their @prepare_fb hook.
> */
> int (*prepare_fb)(struct drm_simple_display_pipe *pipe,
> struct drm_plane_state *plane_state);
> --
> 2.32.0.rc2