Re: [PATCH 09/22] drm/vkms: Introduce config for plane format

["José Expósito" <jose.exposito89@gmail.com>]

On Sat, Oct 18, 2025 at 04:01:09AM +0200, Louis Chauvet wrote:
> VKMS driver supports all the pixel formats for planes, but for testing it
> can be useful to only advertise few of them. This new configuration
> interface will allow configuring the pixel format per planes.
> 
> Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
> ---
>  drivers/gpu/drm/vkms/vkms_config.c | 99 ++++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/vkms/vkms_config.h | 49 +++++++++++++++++++
>  drivers/gpu/drm/vkms/vkms_plane.c  | 39 +--------------
>  3 files changed, 150 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_config.c b/drivers/gpu/drm/vkms/vkms_config.c
> index 8f00ca21ed6e..0b975a0d47aa 100644
> --- a/drivers/gpu/drm/vkms/vkms_config.c
> +++ b/drivers/gpu/drm/vkms/vkms_config.c
> @@ -8,6 +8,42 @@
>  
>  #include "vkms_config.h"
>  
> +static const u32 vkms_supported_plane_formats[] = {
> +	DRM_FORMAT_ARGB8888,
> +	DRM_FORMAT_ABGR8888,
> +	DRM_FORMAT_BGRA8888,
> +	DRM_FORMAT_RGBA8888,
> +	DRM_FORMAT_XRGB8888,
> +	DRM_FORMAT_XBGR8888,
> +	DRM_FORMAT_RGB888,
> +	DRM_FORMAT_BGR888,
> +	DRM_FORMAT_XRGB16161616,
> +	DRM_FORMAT_XBGR16161616,
> +	DRM_FORMAT_ARGB16161616,
> +	DRM_FORMAT_ABGR16161616,
> +	DRM_FORMAT_RGB565,
> +	DRM_FORMAT_BGR565,
> +	DRM_FORMAT_NV12,
> +	DRM_FORMAT_NV16,
> +	DRM_FORMAT_NV24,
> +	DRM_FORMAT_NV21,
> +	DRM_FORMAT_NV61,
> +	DRM_FORMAT_NV42,
> +	DRM_FORMAT_YUV420,
> +	DRM_FORMAT_YUV422,
> +	DRM_FORMAT_YUV444,
> +	DRM_FORMAT_YVU420,
> +	DRM_FORMAT_YVU422,
> +	DRM_FORMAT_YVU444,
> +	DRM_FORMAT_P010,
> +	DRM_FORMAT_P012,
> +	DRM_FORMAT_P016,
> +	DRM_FORMAT_R1,
> +	DRM_FORMAT_R2,
> +	DRM_FORMAT_R4,
> +	DRM_FORMAT_R8,
> +};
> +
>  struct vkms_config *vkms_config_create(const char *dev_name)
>  {
>  	struct vkms_config *config;
> @@ -435,6 +471,11 @@ struct vkms_config_plane *vkms_config_create_plane(struct vkms_config *config)
>  	if (!plane_cfg)
>  		return ERR_PTR(-ENOMEM);
>  
> +	if (vkms_config_plane_add_all_formats(plane_cfg)) {
> +		kfree(plane_cfg);
> +		return ERR_PTR(-ENOMEM);
> +	}
> +
>  	plane_cfg->config = config;
>  	vkms_config_plane_set_type(plane_cfg, DRM_PLANE_TYPE_OVERLAY);
>  	vkms_config_plane_set_name(plane_cfg, NULL);
> @@ -563,6 +604,64 @@ static struct vkms_config_plane *vkms_config_crtc_get_plane(const struct vkms_co
>  	return NULL;
>  }
>  
> +int __must_check vkms_config_plane_add_all_formats(struct vkms_config_plane *plane_cfg)
> +{
> +	u32 *ret = krealloc_array(plane_cfg->supported_formats,
> +				  ARRAY_SIZE(vkms_supported_plane_formats),
> +				  sizeof(uint32_t), GFP_KERNEL);
> +	if (!ret)
> +		return -ENOMEM;
> +	plane_cfg->supported_formats = ret;
> +
> +	memcpy(plane_cfg->supported_formats, vkms_supported_plane_formats,
> +	       sizeof(vkms_supported_plane_formats));
> +	plane_cfg->supported_formats_count = ARRAY_SIZE(vkms_supported_plane_formats);
> +	return 0;
> +}
> +
> +int __must_check vkms_config_plane_add_format(struct vkms_config_plane *plane_cfg, u32 drm_format)
> +{
> +	bool found = false;
> +
> +	for (int i = 0; i < ARRAY_SIZE(vkms_supported_plane_formats); i++) {
> +		if (vkms_supported_plane_formats[i] == drm_format)
> +			found = true;

Missing break?

> +	}
> +
> +	if (!found)
> +		return -EINVAL;
> +	for (unsigned int i = 0; i < plane_cfg->supported_formats_count; i++) {
> +		if (plane_cfg->supported_formats[i] == drm_format)
> +			return 0;
> +	}
> +	u32 *new_ptr = krealloc_array(plane_cfg->supported_formats,
> +				      plane_cfg->supported_formats_count + 1,
> +				      sizeof(*plane_cfg->supported_formats), GFP_KERNEL);
> +	if (!new_ptr)
> +		return -ENOMEM;
> +
> +	plane_cfg->supported_formats = new_ptr;
> +	plane_cfg->supported_formats[plane_cfg->supported_formats_count] = drm_format;
> +	plane_cfg->supported_formats_count++;
> +
> +	return 0;
> +}
> +
> +void vkms_config_plane_remove_all_formats(struct vkms_config_plane *plane_cfg)
> +{
> +	plane_cfg->supported_formats_count = 0;
> +}
> +
> +void vkms_config_plane_remove_format(struct vkms_config_plane *plane_cfg, u32 drm_format)
> +{
> +	for (unsigned int i = 0; i < plane_cfg->supported_formats_count; i++) {
> +		if (plane_cfg->supported_formats[i] == drm_format) {
> +			plane_cfg->supported_formats[i] = plane_cfg->supported_formats[plane_cfg->supported_formats_count - 1];
> +			plane_cfg->supported_formats_count--;
> +		}
> +	}
> +}
> +
>  struct vkms_config_plane *vkms_config_crtc_primary_plane(const struct vkms_config *config,
>  							 struct vkms_config_crtc *crtc_cfg)
>  {
> diff --git a/drivers/gpu/drm/vkms/vkms_config.h b/drivers/gpu/drm/vkms/vkms_config.h
> index 8127e12f00dc..0b7067508e5f 100644
> --- a/drivers/gpu/drm/vkms/vkms_config.h
> +++ b/drivers/gpu/drm/vkms/vkms_config.h
> @@ -62,6 +62,8 @@ struct vkms_config_plane {
>  	unsigned int supported_color_encoding;
>  	enum drm_color_range default_color_range;
>  	unsigned int supported_color_range;
> +	u32 *supported_formats;
> +	unsigned int supported_formats_count;
>  	struct xarray possible_crtcs;
>  
>  	/* Internal usage */
> @@ -404,6 +406,53 @@ vkms_config_plane_set_supported_color_range(struct vkms_config_plane *plane_cfg,
>  	plane_cfg->supported_color_range = supported_color_range;
>  }
>  
> +static inline u32 *
> +vkms_config_plane_get_supported_formats(struct vkms_config_plane *plane_cfg)
> +{
> +	return plane_cfg->supported_formats;
> +}
> +
> +static inline unsigned int
> +vkms_config_plane_get_supported_formats_count(struct vkms_config_plane *plane_cfg)
> +{
> +	return plane_cfg->supported_formats_count;
> +}
> +
> +/** vkms_config_plane_add_format - Add a format to the list of supported format of a plane
> + *
> + * The passed drm_format can already be present in the list. This may fail if the allocation of a
> + * bigger array fails.
> + *
> + * @plane_cfg: Plane to add the format to
> + * @drm_format: Format to add to this plane
> + *
> + * Returns: 0 on success, -ENOMEM if array allocation fails, -EINVAL if the format is not supported
> + * by VKMS
> + */
> +int __must_check vkms_config_plane_add_format(struct vkms_config_plane *plane_cfg, u32 drm_format);
> +
> +/**
> + * vkms_config_plane_add_all_formats - Helper to quickly add all the supported formats
> + * @plane_cfg: Plane to add the formats to
> + *
> + * Returns: 0 on success, -ENOMEM if array allocation fails, -EINVAL if the format is not supported
> + * by VKMS
> + */
> +int __must_check vkms_config_plane_add_all_formats(struct vkms_config_plane *plane_cfg);
> +
> +/**
> + * vkms_config_plane_remove_format - Remove a specific format from a plane
> + * @plane_cfg: Plane to remove the format to
> + * @drm_format: Format to remove
> + */
> +void vkms_config_plane_remove_format(struct vkms_config_plane *plane_cfg, u32 drm_format);
> +
> +/**
> + * vkms_config_plane_remove_all_formats - Remove all formast from a plane
> + * @plane_cfg: Plane to remove the formats from
> + */
> +void vkms_config_plane_remove_all_formats(struct vkms_config_plane *plane_cfg);
> +
>  /**
>   * vkms_config_plane_set_name() - Set the plane name
>   * @plane_cfg: Plane to set the name to
> diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
> index ab719da2ca0b..0414865915d8 100644
> --- a/drivers/gpu/drm/vkms/vkms_plane.c
> +++ b/drivers/gpu/drm/vkms/vkms_plane.c
> @@ -14,42 +14,6 @@
>  #include "vkms_formats.h"
>  #include "vkms_config.h"
>  
> -static const u32 vkms_formats[] = {
> -	DRM_FORMAT_ARGB8888,
> -	DRM_FORMAT_ABGR8888,
> -	DRM_FORMAT_BGRA8888,
> -	DRM_FORMAT_RGBA8888,
> -	DRM_FORMAT_XRGB8888,
> -	DRM_FORMAT_XBGR8888,
> -	DRM_FORMAT_RGB888,
> -	DRM_FORMAT_BGR888,
> -	DRM_FORMAT_XRGB16161616,
> -	DRM_FORMAT_XBGR16161616,
> -	DRM_FORMAT_ARGB16161616,
> -	DRM_FORMAT_ABGR16161616,
> -	DRM_FORMAT_RGB565,
> -	DRM_FORMAT_BGR565,
> -	DRM_FORMAT_NV12,
> -	DRM_FORMAT_NV16,
> -	DRM_FORMAT_NV24,
> -	DRM_FORMAT_NV21,
> -	DRM_FORMAT_NV61,
> -	DRM_FORMAT_NV42,
> -	DRM_FORMAT_YUV420,
> -	DRM_FORMAT_YUV422,
> -	DRM_FORMAT_YUV444,
> -	DRM_FORMAT_YVU420,
> -	DRM_FORMAT_YVU422,
> -	DRM_FORMAT_YVU444,
> -	DRM_FORMAT_P010,
> -	DRM_FORMAT_P012,
> -	DRM_FORMAT_P016,
> -	DRM_FORMAT_R1,
> -	DRM_FORMAT_R2,
> -	DRM_FORMAT_R4,
> -	DRM_FORMAT_R8,
> -};
> -
>  static struct drm_plane_state *
>  vkms_plane_duplicate_state(struct drm_plane *plane)
>  {
> @@ -226,7 +190,8 @@ struct vkms_plane *vkms_plane_init(struct vkms_device *vkmsdev,
>  
>  	plane = drmm_universal_plane_alloc(dev, struct vkms_plane, base, 0,
>  					   &vkms_plane_funcs,
> -					   vkms_formats, ARRAY_SIZE(vkms_formats),
> +					   vkms_config_plane_get_supported_formats(config),
> +					   vkms_config_plane_get_supported_formats_count(config),
>  					   NULL, vkms_config_plane_get_type(config),
>  					   vkms_config_plane_get_name(config));
>  	if (IS_ERR(plane))
> 
> -- 
> 2.51.0
>