diff mbox

[v2,2/5] drm: Centralize format information

Message ID 1465342538-31220-3-git-send-email-laurent.pinchart@ideasonboard.com (mailing list archive)
State New, archived
Headers show

Commit Message

Laurent Pinchart June 7, 2016, 11:35 p.m. UTC 
Various pieces of information about DRM formats (number of planes, color
depth, chroma subsampling, ...) are scattered across different helper
functions in the DRM core. Callers of those functions often need to
access more than a single parameter of the format, leading to
inefficiencies due to multiple lookups.

Centralize all format information in a data structure and create a
function to look up information based on the format 4CC.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/gpu/drm/drm_fourcc.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_fourcc.h     | 21 +++++++++++
 2 files changed, 105 insertions(+)

Comments

Eric Engestrom June 8, 2016, 10:27 a.m. UTC | #1 
On Wed, Jun 08, 2016 at 02:35:35AM +0300, Laurent Pinchart wrote:
> Various pieces of information about DRM formats (number of planes, color
> depth, chroma subsampling, ...) are scattered across different helper
> functions in the DRM core. Callers of those functions often need to
> access more than a single parameter of the format, leading to
> inefficiencies due to multiple lookups.
> 
> Centralize all format information in a data structure and create a
> function to look up information based on the format 4CC.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
>  drivers/gpu/drm/drm_fourcc.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_fourcc.h     | 21 +++++++++++
>  2 files changed, 105 insertions(+)
> 

[snip]

> diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
> index 7f90a396cf2b..d33411bd19b1 100644
> --- a/include/drm/drm_fourcc.h
> +++ b/include/drm/drm_fourcc.h
> @@ -25,6 +25,27 @@
>  #include <linux/types.h>
>  #include <uapi/drm/drm_fourcc.h>
>  
> +/**
> + * struct drm_format_info - information about a DRM format
> + * @format: 4CC format identifier (DRM_FORMAT_*)
> + * @depth: color depth (number of bits per pixel excluding padding bits)
> + * @bpp: number of bits per pixel including padding
> + * @num_planes: number of color planes (1 to 3)
> + * @cpp: number of bytes per pixel (per plane)
> + * @hsub: horizontal chroma subsampling factor
> + * @vsub: vertical chroma subsampling factor
> + */
> +struct drm_format_info {
> +	u32 format;
> +	u8 depth;
> +	u8 bpp;

I think `bpp` is redundant here: it's always `cpp[0] << 3`, except when
ignored (yuv formats), which `depth` already indicates by being 0.

Unless I missed something, the only change required to drop this field
would be in patch #3, in drm_fb_get_bpp_depth():

	*bpp = info->bpp;

becomes:

	*bpp = info->depth ? info->cpp[0] << 3 : 0;

I'm not really opposed to it being here if someone else finds it useful
though, so either way, the series is:
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

> +	u8 num_planes;
> +	u8 cpp[3];
> +	u8 hsub;
> +	u8 vsub;
> +};
> +
> +const struct drm_format_info *drm_format_info(u32 format);
>  void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth, int *bpp);
>  int drm_format_num_planes(uint32_t format);
>  int drm_format_plane_cpp(uint32_t format, int plane);
> -- 
> Regards,
> 
> Laurent Pinchart
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Laurent Pinchart June 8, 2016, 2:31 p.m. UTC | #2 
Hi Eric,

On Wednesday 08 Jun 2016 11:27:32 Eric Engestrom wrote:
> On Wed, Jun 08, 2016 at 02:35:35AM +0300, Laurent Pinchart wrote:
> > Various pieces of information about DRM formats (number of planes, color
> > depth, chroma subsampling, ...) are scattered across different helper
> > functions in the DRM core. Callers of those functions often need to
> > access more than a single parameter of the format, leading to
> > inefficiencies due to multiple lookups.
> > 
> > Centralize all format information in a data structure and create a
> > function to look up information based on the format 4CC.
> > 
> > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > ---
> > 
> >  drivers/gpu/drm/drm_fourcc.c | 84 +++++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_fourcc.h     | 21 +++++++++++
> >  2 files changed, 105 insertions(+)
> 
> [snip]
> 
> > diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
> > index 7f90a396cf2b..d33411bd19b1 100644
> > --- a/include/drm/drm_fourcc.h
> > +++ b/include/drm/drm_fourcc.h
> > @@ -25,6 +25,27 @@
> > 
> >  #include <linux/types.h>
> >  #include <uapi/drm/drm_fourcc.h>
> > 
> > +/**
> > + * struct drm_format_info - information about a DRM format
> > + * @format: 4CC format identifier (DRM_FORMAT_*)
> > + * @depth: color depth (number of bits per pixel excluding padding bits)
> > + * @bpp: number of bits per pixel including padding
> > + * @num_planes: number of color planes (1 to 3)
> > + * @cpp: number of bytes per pixel (per plane)
> > + * @hsub: horizontal chroma subsampling factor
> > + * @vsub: vertical chroma subsampling factor
> > + */
> > +struct drm_format_info {
> > +	u32 format;
> > +	u8 depth;
> > +	u8 bpp;
> 
> I think `bpp` is redundant here: it's always `cpp[0] << 3`, except when
> ignored (yuv formats), which `depth` already indicates by being 0.
> 
> Unless I missed something, the only change required to drop this field
> would be in patch #3, in drm_fb_get_bpp_depth():
> 
> 	*bpp = info->bpp;
> 
> becomes:
> 
> 	*bpp = info->depth ? info->cpp[0] << 3 : 0;

I agree with you, it's redundant. I'll remove it, and will also patch callers 
to user drm_format_cpp() instead of drm_fb_get_bpp_depth() where applicable.

> I'm not really opposed to it being here if someone else finds it useful
> though, so either way, the series is:
> Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
> 
> > +	u8 num_planes;
> > +	u8 cpp[3];
> > +	u8 hsub;
> > +	u8 vsub;
> > +};
> > +
> > +const struct drm_format_info *drm_format_info(u32 format);
> > 
> >  void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth, int
> >  *bpp);
> >  int drm_format_num_planes(uint32_t format);
> >  int drm_format_plane_cpp(uint32_t format, int plane);
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
index 0645c85d5f95..463254dc7f1e 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -62,6 +62,90 @@  const char *drm_get_format_name(uint32_t format)
 EXPORT_SYMBOL(drm_get_format_name);
 
 /**
+ * drm_format_info - query information for a given format
+ * @format: pixel format (DRM_FORMAT_*)
+ *
+ * Returns:
+ * The instance of struct drm_format_info that describes the pixel format, or
+ * NULL if the format is unsupported.
+ */
+const struct drm_format_info *drm_format_info(u32 format)
+{
+	static const struct drm_format_info formats[] = { 
+		{ .format = DRM_FORMAT_C8,		.depth = 8,  .bpp = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGB332,		.depth = 8,  .bpp = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGR233,		.depth = 8,  .bpp = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XRGB4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XBGR4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBX4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRX4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ARGB4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ABGR4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBA4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRA4444,	.depth = 12, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XRGB1555,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XBGR1555,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBX5551,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRX5551,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ARGB1555,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ABGR1555,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBA5551,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRA5551,	.depth = 15, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGB565,		.depth = 16, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGR565,		.depth = 16, .bpp = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGB888,		.depth = 24, .bpp = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGR888,		.depth = 24, .bpp = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XRGB8888,	.depth = 24, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XBGR8888,	.depth = 24, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBX8888,	.depth = 24, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRX8888,	.depth = 24, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XRGB2101010,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_XBGR2101010,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBX1010102,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRX1010102,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ARGB2101010,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ABGR2101010,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBA1010102,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRA1010102,	.depth = 30, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ARGB8888,	.depth = 32, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_ABGR8888,	.depth = 32, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_RGBA8888,	.depth = 32, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_BGRA8888,	.depth = 32, .bpp = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_YUV410,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4 },
+		{ .format = DRM_FORMAT_YVU410,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4 },
+		{ .format = DRM_FORMAT_YUV411,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1 },
+		{ .format = DRM_FORMAT_YVU411,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1 },
+		{ .format = DRM_FORMAT_YUV420,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2 },
+		{ .format = DRM_FORMAT_YVU420,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2 },
+		{ .format = DRM_FORMAT_YUV422,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_YVU422,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_YUV444,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_YVU444,		.depth = 0,  .bpp = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_NV12,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2 },
+		{ .format = DRM_FORMAT_NV21,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2 },
+		{ .format = DRM_FORMAT_NV16,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_NV61,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_NV24,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_NV42,		.depth = 0,  .bpp = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1 },
+		{ .format = DRM_FORMAT_YUYV,		.depth = 0,  .bpp = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_YVYU,		.depth = 0,  .bpp = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_UYVY,		.depth = 0,  .bpp = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_VYUY,		.depth = 0,  .bpp = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
+		{ .format = DRM_FORMAT_AYUV,		.depth = 0,  .bpp = 0,  .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
+	};
+
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
+		if (formats[i].format == format)
+			return &formats[i];
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL(drm_format_info);
+
+/**
  * drm_fb_get_bpp_depth - get the bpp/depth values for format
  * @format: pixel format (DRM_FORMAT_*)
  * @depth: storage for the depth value
diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
index 7f90a396cf2b..d33411bd19b1 100644
--- a/include/drm/drm_fourcc.h
+++ b/include/drm/drm_fourcc.h
@@ -25,6 +25,27 @@ 
 #include <linux/types.h>
 #include <uapi/drm/drm_fourcc.h>
 
+/**
+ * struct drm_format_info - information about a DRM format
+ * @format: 4CC format identifier (DRM_FORMAT_*)
+ * @depth: color depth (number of bits per pixel excluding padding bits)
+ * @bpp: number of bits per pixel including padding
+ * @num_planes: number of color planes (1 to 3)
+ * @cpp: number of bytes per pixel (per plane)
+ * @hsub: horizontal chroma subsampling factor
+ * @vsub: vertical chroma subsampling factor
+ */
+struct drm_format_info {
+	u32 format;
+	u8 depth;
+	u8 bpp;
+	u8 num_planes;
+	u8 cpp[3];
+	u8 hsub;
+	u8 vsub;
+};
+
+const struct drm_format_info *drm_format_info(u32 format);
 void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth, int *bpp);
 int drm_format_num_planes(uint32_t format);
 int drm_format_plane_cpp(uint32_t format, int plane);