>-----Original Message----- >From: Alexandru-Cosmin Gheorghe [mailto:Alexandru- >[email protected]] >Sent: Tuesday, August 21, 2018 3:00 PM >To: Shankar, Uma <[email protected]> >Cc: [email protected]; [email protected]; >[email protected]; [email protected]; [email protected]; >Syrjala, Ville <[email protected]>; Lankhorst, Maarten ><[email protected]>; [email protected] >Subject: Re: [RFC v4 1/8] drm: Add Enhanced Gamma LUT precision structure > >Hi Uma, > >On Fri, Aug 17, 2018 at 07:48:44PM +0530, Uma Shankar wrote: >> Existing LUT precision structure is having only 16 bit precision. This >> is not enough for upcoming enhanced hardwares and advance usecases >> like HDR processing. Hence added a new structure with 32 bit precision >> values. Also added the code, for extracting the same from values >> passed from userspace. >> >> v4: Rebase >> >> Signed-off-by: Uma Shankar <[email protected]> >> --- >> drivers/gpu/drm/drm_plane.c | 19 +++++++++++++++++++ >> include/uapi/drm/drm_mode.h | 15 +++++++++++++++ >> 2 files changed, 34 insertions(+) >> >> diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c >> index 6153cbd..cd71fd0 100644 >> --- a/drivers/gpu/drm/drm_plane.c >> +++ b/drivers/gpu/drm/drm_plane.c >> @@ -430,6 +430,25 @@ void drm_plane_force_disable(struct drm_plane >> *plane) } EXPORT_SYMBOL(drm_plane_force_disable); >> >> +/* >> + * Added to accommodate enhanced LUT precision. >> + * Max LUT precision is 32 bits. >> + */ >> +uint32_t drm_color_lut_extract_ext(uint32_t user_input, uint32_t >> +bit_precision) > >You should declare this function in a header file as well.
Thanks Alexandru for the review. Sure, will fix that and resend. >With that fixed >Reviewed-by: Alexandru Gheorghe <[email protected]> > > >> +{ >> + uint32_t val = user_input; >> + uint32_t max = 0xffffffff >> (32 - bit_precision); >> + >> + /* Round only if we're not using full precision. */ >> + if (bit_precision < 32) { >> + val += 1UL << (32 - bit_precision - 1); >> + val >>= 32 - bit_precision; >> + } >> + >> + return clamp_val(val, 0, max); >> +} >> +EXPORT_SYMBOL(drm_color_lut_extract_ext); >> + >> /** >> * drm_mode_plane_set_obj_prop - set the value of a property >> * @plane: drm plane object to set property value for diff --git >> a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index >> 8d67243..874407b 100644 >> --- a/include/uapi/drm/drm_mode.h >> +++ b/include/uapi/drm/drm_mode.h >> @@ -629,6 +629,21 @@ struct drm_color_lut { >> __u16 reserved; >> }; >> >> +/* >> + * Creating 32 bit palette entries for better data >> + * precision. This will be required for HDR and >> + * similar color processing usecases. >> + */ >> +struct drm_color_lut_ext { >> + /* >> + * Data is U0.32 fixed point format. >> + */ >> + __u32 red; >> + __u32 green; >> + __u32 blue; >> + __u32 reserved; >> +}; >> + >> #define DRM_MODE_PAGE_FLIP_EVENT 0x01 #define >> DRM_MODE_PAGE_FLIP_ASYNC 0x02 #define >> DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE 0x4 >> -- >> 1.9.1 >> >> _______________________________________________ >> dri-devel mailing list >> [email protected] >> https://lists.freedesktop.org/mailman/listinfo/dri-devel > >-- >Cheers, >Alex G _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
