RE: [PATCH 08/28] drm: Add Color lut range attributes

["Shankar, Uma" <uma.shankar@intel.com>]

> -----Original Message-----
> From: Sebastian Wick <sebastian.wick@redhat.com>
> Sent: Tuesday, February 13, 2024 5:34 PM
> To: Shankar, Uma <uma.shankar@intel.com>
> Cc: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org;
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> Subject: Re: [PATCH 08/28] drm: Add Color lut range attributes
> 
> On Tue, Feb 13, 2024 at 12:18:15PM +0530, Uma Shankar wrote:
> > This defines a new structure to define color lut ranges, along with
> > related macro definitions and enums. This will help describe segmented
> > lut ranges/PWL LUTs in the hardware.
> >
> > Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> > Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
> > ---
> >  include/uapi/drm/drm_mode.h | 58
> > +++++++++++++++++++++++++++++++++++++
> >  1 file changed, 58 insertions(+)
> >
> > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
> > index af67f32e0087..376498715d0e 100644
> > --- a/include/uapi/drm/drm_mode.h
> > +++ b/include/uapi/drm/drm_mode.h
> > @@ -1014,6 +1014,64 @@ struct hdr_output_metadata {
> >  				  DRM_MODE_PAGE_FLIP_ASYNC | \
> >  				  DRM_MODE_PAGE_FLIP_TARGET)
> >
> 
> All of this uses DRM_MODE_LUT namespace but it seems specifically for the drm
> colorop of type DRM_COLOROP_1D_LUT. Let's be consistent with the naming.

Yeah Sebastian, we will update this and get it aligned.
Thanks for pointing out.

Regards,
Uma Shankar

> > +/**
> > + * DRM_MODE_LUT_INTERPOLATE
> > + *
> > + * linearly interpolate between the points  */ #define
> > +DRM_MODE_LUT_INTERPOLATE BIT(0)
> > +
> > +/**
> > + * DRM_MODE_LUT_REUSE_LAST
> > + *
> > + * the last value of the previous range is the
> > + * first value of the current range.
> > + */
> > +#define DRM_MODE_LUT_REUSE_LAST BIT(1)
> > +
> > +/**
> > + * DRM_MODE_LUT_NON_DECREASING
> > + *
> > + * the curve must be non-decreasing
> > + */
> > +#define DRM_MODE_LUT_NON_DECREASING BIT(2)
> > +
> > +/**
> > + * DRM_MODE_LUT_REFLECT_NEGATIVE
> > + *
> > + *  the curve is reflected across origin for negative inputs  */
> > +#define DRM_MODE_LUT_REFLECT_NEGATIVE BIT(3)
> > +
> > +/**
> > + * DRM_MODE_LUT_SINGLE_CHANNEL
> > + *
> > + * the same curve (red) is used for blue and green channels as well
> > +*/ #define DRM_MODE_LUT_SINGLE_CHANNEL BIT(4)
> > +
> > +/**
> > + * struct drm_color_lut_range
> > + *
> > + * structure to advertise capability of a color hardware
> > + * block that accepts LUT values.  It can represent LUTs with
> > + * varied number of entries and distributions
> > + * (Multi segmented, Logarithmic etc).
> > + */
> > +
> > +struct drm_color_lut_range {
> > +	/* DRM_MODE_LUT_* */
> > +	__u32 flags;
> > +	/* number of points on the curve */
> > +	__u16 count;
> > +	/* input/output bits per component */
> > +	__u8 input_bpc, output_bpc;
> > +	/* input start/end values */
> > +	__s32 start, end;
> > +	/* output min/max values */
> > +	__s32 min, max;
> > +};
> > +
> >  /*
> >   * Request a page flip on the specified crtc.
> >   *
> > --
> > 2.42.0
> >