Re: [PATCH v5 11/16] drm/vkms: Add YUV support

[Louis Chauvet <louis.chauvet@bootlin.com>]

Le 13/03/24 - 12:20, Randy Dunlap a écrit :
> Hi,
> 
> On 3/13/24 10:45, Louis Chauvet wrote:
> > From: Arthur Grillo <arthurgrillo@riseup.net>
> > 
> 
> > 
> > Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
> > [Louis Chauvet:
> > - Adapted Arthur's work
> > - Implemented the read_line_t callbacks for yuv
> > - add struct conversion_matrix
> > - remove struct pixel_yuv_u8
> > - update the commit message
> > - Merge the modifications from Arthur]
> > Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com>
> > ---
> >  drivers/gpu/drm/vkms/vkms_drv.h     |  22 ++
> >  drivers/gpu/drm/vkms/vkms_formats.c | 431 ++++++++++++++++++++++++++++++++++++
> >  drivers/gpu/drm/vkms/vkms_formats.h |   4 +
> >  drivers/gpu/drm/vkms/vkms_plane.c   |  17 +-
> >  4 files changed, 473 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> > index 23e1d247468d..f3116084de5a 100644
> > --- a/drivers/gpu/drm/vkms/vkms_drv.h
> > +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> > @@ -99,6 +99,27 @@ typedef void (*pixel_read_line_t)(const struct vkms_plane_state *plane, int x_st
> >  				  int y_start, enum pixel_read_direction direction, int count,
> >  				  struct pixel_argb_u16 out_pixel[]);
> >  
> > +/**
> > + * CONVERSION_MATRIX_FLOAT_DEPTH - Number of digits after the point for conversion matrix values
> 
> This should be
> 
> + * define CONVERSION_MATRIX_FLOAT_DEPTH - Number of digits after the point for conversion matrix values
> 
> to conform to kernel-doc format.
> 
> > + */
> > +#define CONVERSION_MATRIX_FLOAT_DEPTH 32
> > +

Hi Randy,

Thanks for your feedback.

I missed it while squashing Arthur's work, but this constant is not needed 
anymore, it will be removed in v6.

For all other kernel-doc formatting (PATCHv5 03/16, PATCH V5 05/16), I 
will correct them in the v6.

Kind regards,
Louis Chauvet

> > diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
> > index 1449a0e6c706..edbf4b321b91 100644
> > --- a/drivers/gpu/drm/vkms/vkms_formats.c
> > +++ b/drivers/gpu/drm/vkms/vkms_formats.c
> 
> > +/**
> > + * get_conversion_matrix_to_argb_u16() - Retrieve the correct yuv to rgb conversion matrix for a
> > + * given encoding and range.
> > + *
> > + * If the matrix is not found, return a null pointer. In all other cases, it return a simple
> > + * diagonal matrix, which act as a "no-op".
> > + *
> > + * @format: DRM_FORMAT_* value for which to obtain a conversion function (see [drm_fourcc.h])
> > + * @encoding: DRM_COLOR_* value for which to obtain a conversion matrix
> > + * @range: DRM_COLOR_*_RANGE value for which to obtain a conversion matrix
> > + */
> > +struct conversion_matrix *
> > +get_conversion_matrix_to_argb_u16(u32 format, enum drm_color_encoding encoding,
> > +				  enum drm_color_range range)
> > +{
> > +	static struct conversion_matrix no_operation = {
> > +		.matrix = {
> > +			{ 4294967296, 0,          0, },
> > +			{ 0,          4294967296, 0, },
> > +			{ 0,          0,          4294967296, },
> > +		},
> > +		.y_offset = 0,
> > +	};
> > +
> > +	/*
> > +	 * Those matrixies were generated using the colour python framework
> 
> 	         matrices
> 
> > +	 *
> > +	 * Below are the function calls used to generate eac matrix, go to
> 
> 	                                                 each
> 
> > +	 * https://colour.readthedocs.io/en/develop/generated/colour.matrix_YCbCr.html
> > +	 * for more info:
> > +	 *
> > +	 * numpy.around(colour.matrix_YCbCr(K=colour.WEIGHTS_YCBCR["ITU-R BT.601"],
> > +	 *                                  is_legal = False,
> > +	 *                                  bits = 8) * 2**32).astype(int)
> > +	 */
> 
> > +
> >  /**
> 
> Please convert this comment to kernel-doc format or just use "/*" to begin
> the comment.
> 
> >   * Retrieve the correct write_pixel function for a specific format.
> >   * If the format is not supported by VKMS a warn is emitted and a dummy "don't do anything"
> 
> > diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
> > index 8875bed76410..987dd2b686a8 100644
> > --- a/drivers/gpu/drm/vkms/vkms_plane.c
> > +++ b/drivers/gpu/drm/vkms/vkms_plane.c
> 
> 
> thanks.
> -- 
> #Randy

-- 
Louis Chauvet, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com