[PATCH v3 02/15] drm: Centralize format information

Ville Syrjälä ville.syrjala at linux.intel.com
Thu Jun 9 12:23:17 UTC 2016


On Thu, Jun 09, 2016 at 10:52:23AM +0200, Daniel Vetter wrote:
> On Thu, Jun 09, 2016 at 02:32:06AM +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 at ideasonboard.com>
> > ---
> >  drivers/gpu/drm/drm_fourcc.c | 84 ++++++++++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_fourcc.h     | 19 ++++++++++
> >  2 files changed, 103 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
> > index 0645c85d5f95..47b9abd743be 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)
> 
> Bikeshed on your pixel format description table. I think the approach I've
> seen in gallium/mesa to describe pixel formats is a lot more generic, and
> we might as well adopt it when we change. Idea is to have a block size
> measure in pixels (both h and v), and then cpp is bytes_per_block. This is
> essentially what you have with hsub and vsub already, except confusing
> names, more ill-defined (since it only makes sense for yuv) and less
> generic. A few examples:

I think you have your confusion backwards. Calling something a block in
planar formats would be more confusing. The only thing that really
matters is the relative position of the samples between the planes.
So there really is no "block" in there.

> 	h_blocksize	v_blocksize	bytes_per_block (per-plane)
> YUV410	4		4		{4, 1, 1}
> YUV411	4		1		{4, 1, 1}
> 
> hsub = h_blocksize / bytes_per_block[U/V plane]
> vsub = v_blocksize / bytes_per_block[U/V plane]
> 
> *_blocksize is in pixels
> 
> [not entirely sure on the precise data, but that's kinda the point.]
> 
> Ofc should maybe check that those helpers are only called on yuv planar
> formats, too. This way we could also remove some of the comments in
> drm_fourcc.h, or at least make the more clear. Another benefit is that
> with this it's possible to write entirely generic size/stride checking
> functions
> 
> Oh and if we go with this, some asciiart for what's meant (in sphinx/rst,
> that will happen in 4.8) would be awesome.
> -Daniel
> 
> > +{
> > +	static const struct drm_format_info formats[] = { 
> > +		{ .format = DRM_FORMAT_C8,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGB332,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGR233,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XRGB4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XBGR4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBX4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRX4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ARGB4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ABGR4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBA4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRA4444,	.depth = 12, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XRGB1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XBGR1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBX5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRX5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ARGB1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ABGR1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBA5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRA5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGB565,		.depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGR565,		.depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGB888,		.depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGR888,		.depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XRGB8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XBGR8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBX8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRX8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XRGB2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_XBGR2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBX1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRX1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ARGB2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ABGR2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBA1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRA1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ARGB8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_ABGR8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_RGBA8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_BGRA8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YUV410,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4 },
> > +		{ .format = DRM_FORMAT_YVU410,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4 },
> > +		{ .format = DRM_FORMAT_YUV411,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YVU411,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YUV420,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2 },
> > +		{ .format = DRM_FORMAT_YVU420,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2 },
> > +		{ .format = DRM_FORMAT_YUV422,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YVU422,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YUV444,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YVU444,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_NV12,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2 },
> > +		{ .format = DRM_FORMAT_NV21,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2 },
> > +		{ .format = DRM_FORMAT_NV16,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_NV61,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_NV24,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_NV42,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YUYV,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_YVYU,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_UYVY,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_VYUY,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1 },
> > +		{ .format = DRM_FORMAT_AYUV,		.depth = 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..b077df507b51 100644
> > --- a/include/drm/drm_fourcc.h
> > +++ b/include/drm/drm_fourcc.h
> > @@ -25,6 +25,25 @@
> >  #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)
> > + * @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 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 at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Ville Syrjälä
Intel OTC


More information about the dri-devel mailing list