Re: [PATCH 01/10] drm/i915: Introduce sanity to the plane_config pointer vs. array thing

Jani Nikula
2026-04-10T15:41:06Z

On Fri, 10 Apr 2026, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> The "plane_config" vs. "plane_configs" naming difference is very
> subtle, making it far too easy to use the wrong thing by accident.
> Introduce a separate type for the array, making it impossible to
> pass in the wrong thing. And while at it name the variable
> "all_plane_configs" to help the poor reader make sense of things.
>
> The .config_fini() prototype also mistakenly used the plural
> form despite only taking in a singular plane_config. So fix that
> one up as well.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Nice!

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> ---
> .../drm/i915/display/intel_initial_plane.c | 21 ++++++++++++-------
> include/drm/intel/display_parent_interface.h | 2 +-
> 2 files changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_initial_plane.c b/drivers/gpu/drm/i915/display/intel_initial_plane.c
> index ee545c033da6..4f51083dbd11 100644
> --- a/drivers/gpu/drm/i915/display/intel_initial_plane.c
> +++ b/drivers/gpu/drm/i915/display/intel_initial_plane.c
> @@ -11,6 +11,10 @@
> #include "intel_initial_plane.h"
> #include "intel_plane.h"
>
> +struct intel_initial_plane_configs {
> + struct intel_initial_plane_config config[I915_MAX_PIPES];
> +};
> +
> void intel_initial_plane_vblank_wait(struct intel_crtc *crtc)
> {
> struct intel_display *display = to_intel_display(crtc);
> @@ -20,7 +24,7 @@ void intel_initial_plane_vblank_wait(struct intel_crtc *crtc)
>
> static const struct intel_plane_state *
> intel_reuse_initial_plane_obj(struct intel_crtc *this,
> - const struct intel_initial_plane_config plane_configs[])
> + const struct intel_initial_plane_configs *all_plane_configs)
> {
> struct intel_display *display = to_intel_display(this);
> struct intel_crtc *crtc;
> @@ -39,7 +43,8 @@ intel_reuse_initial_plane_obj(struct intel_crtc *this,
> if (!plane_state->ggtt_vma)
> continue;
>
> - if (plane_configs[this->pipe].base == plane_configs[crtc->pipe].base)
> + if (all_plane_configs->config[this->pipe].base ==
> + all_plane_configs->config[crtc->pipe].base)
> return plane_state;
> }
>
> @@ -69,10 +74,10 @@ intel_alloc_initial_plane_obj(struct intel_display *display,
>
> static void
> intel_find_initial_plane_obj(struct intel_crtc *crtc,
> - struct intel_initial_plane_config plane_configs[])
> + struct intel_initial_plane_configs *all_plane_configs)
> {
> struct intel_display *display = to_intel_display(crtc);
> - struct intel_initial_plane_config *plane_config = &plane_configs[crtc->pipe];
> + struct intel_initial_plane_config *plane_config = &all_plane_configs->config[crtc->pipe];
> struct intel_plane *plane = to_intel_plane(crtc->base.primary);
> struct intel_plane_state *plane_state = to_intel_plane_state(plane->base.state);
> struct drm_framebuffer *fb;
> @@ -93,7 +98,7 @@ intel_find_initial_plane_obj(struct intel_crtc *crtc,
> } else {
> const struct intel_plane_state *other_plane_state;
>
> - other_plane_state = intel_reuse_initial_plane_obj(crtc, plane_configs);
> + other_plane_state = intel_reuse_initial_plane_obj(crtc, all_plane_configs);
> if (!other_plane_state)
> goto nofb;
>
> @@ -158,14 +163,14 @@ static void plane_config_fini(struct intel_display *display,
>
> void intel_initial_plane_config(struct intel_display *display)
> {
> - struct intel_initial_plane_config plane_configs[I915_MAX_PIPES] = {};
> + struct intel_initial_plane_configs all_plane_configs = {};
> struct intel_crtc *crtc;
>
> for_each_intel_crtc(display->drm, crtc) {
> const struct intel_crtc_state *crtc_state =
> to_intel_crtc_state(crtc->base.state);
> struct intel_initial_plane_config *plane_config =
> - &plane_configs[crtc->pipe];
> + &all_plane_configs.config[crtc->pipe];
>
> if (!crtc_state->hw.active)
> continue;
> @@ -183,7 +188,7 @@ void intel_initial_plane_config(struct intel_display *display)
> * If the fb is shared between multiple heads, we'll
> * just get the first one.
> */
> - intel_find_initial_plane_obj(crtc, plane_configs);
> + intel_find_initial_plane_obj(crtc, &all_plane_configs);
>
> if (display->funcs.display->fixup_initial_plane_config(crtc, plane_config))
> intel_initial_plane_vblank_wait(crtc);
> diff --git a/include/drm/intel/display_parent_interface.h b/include/drm/intel/display_parent_interface.h
> index 258e6388ef77..9041897c772e 100644
> --- a/include/drm/intel/display_parent_interface.h
> +++ b/include/drm/intel/display_parent_interface.h
> @@ -91,7 +91,7 @@ struct intel_display_initial_plane_interface {
> struct drm_gem_object *(*alloc_obj)(struct drm_device *drm, struct intel_initial_plane_config *plane_config);
> int (*setup)(struct drm_plane_state *plane_state, struct intel_initial_plane_config *plane_config,
> struct drm_framebuffer *fb, struct i915_vma *vma);
> - void (*config_fini)(struct intel_initial_plane_config *plane_configs);
> + void (*config_fini)(struct intel_initial_plane_config *plane_config);
> };
>
> struct intel_display_irq_interface {

--
Jani Nikula, Intel