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

Daniel Vetter
2021-06-23T16:25:05Z

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)

v3: It's neither ... nor, not not (Sam)

Cc: Sam Ravnborg <sam@ravnborg.org>
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..cf07132d4ee8 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 nor @cleanup_fb hook
+ * set drm_gem_simple_display_pipe_prepare_fb() is called automatically
+ * to implement this. 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