[Intel-gfx] [v3] drm/i915/icl: Handle YCbCr to RGB conversion for BT2020 case

[Shankar, Uma]

>-----Original Message-----
>From: Ville Syrjälä [mailto:ville.syrjala at linux.intel.com]
>Sent: Thursday, May 9, 2019 10:02 PM
>To: Shankar, Uma <uma.shankar at intel.com>
>Cc: intel-gfx at lists.freedesktop.org; Syrjala, Ville <ville.syrjala at intel.com>; Lankhorst,
>Maarten <maarten.lankhorst at intel.com>
>Subject: Re: [Intel-gfx] [v3] drm/i915/icl: Handle YCbCr to RGB conversion for BT2020
>case
>
>On Thu, May 09, 2019 at 09:57:19PM +0530, Uma Shankar wrote:
>> Currently input csc for YCbCR to RGB conversion handles only
>> BT601 and Bt709. Extending it to support BT2020 as well.
>>
>> v2: Fixed the co-efficients for LR to FR conversion, as suggested by
>> Ville.
>>
>> v3: Fixed Y Pre-offset in case of Full Range YCbCr as suggested by
>> Ville.
>>
>> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
>> Signed-off-by: Shashank Sharma <shashank.sharma at intel.com>
>> ---
>>  drivers/gpu/drm/i915/intel_sprite.c | 31
>> +++++++++++++++++++++++++++++--
>>  1 file changed, 29 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_sprite.c
>> b/drivers/gpu/drm/i915/intel_sprite.c
>> index 2913e89..c9c970f 100644
>> --- a/drivers/gpu/drm/i915/intel_sprite.c
>> +++ b/drivers/gpu/drm/i915/intel_sprite.c
>> @@ -433,6 +433,18 @@ int intel_plane_check_src_coordinates(struct
>intel_plane_state *plane_state)
>>  			0x9EF8, 0x7800, 0xABF8,
>>  			0x0, 0x7800,  0x7ED8,
>>  		},
>> +		/*
>> +		 * BT.2020 full range YCbCr -> full range RGB
>> +		 * The matrix required is :
>> +		 * [1.000, 0.000, 1.474,
>> +		 *  1.000, -0.1645, -0.5713,
>> +		 *  1.000, 1.8814, 0.0000]
>> +		 */
>> +		[DRM_COLOR_YCBCR_BT2020] = {
>> +			0x7BC8, 0x7800, 0x0,
>> +			0x8928, 0x7800, 0xAA88,
>> +			0x0, 0x7800, 0x7F10,
>> +		},
>>  	};
>>
>>  	/* Matrix for Limited Range to Full Range Conversion */ @@ -461,6
>> +473,18 @@ int intel_plane_check_src_coordinates(struct intel_plane_state
>*plane_state)
>>  			0x8888, 0x7918, 0xADA8,
>>  			0x0, 0x7918,  0x6870,
>>  		},
>> +		/*
>> +		 * BT.2020 Limited range YCbCr -> full range RGB
>> +		 * The matrix required is :
>> +		 * [1.164, 0.000, 1.678,
>> +		 *  1.164, -0.1873, -0.6504,
>> +		 *  1.164, 2.1417, 0.0000]
>> +		 */
>> +		[DRM_COLOR_YCBCR_BT2020] = {
>> +			0x7D70, 0x7950, 0x0,
>> +			0x8A68, 0x7950, 0xAC00,
>> +			0x0, 0x7950, 0x6890,
>> +		},
>>  	};
>>  	const u16 *csc;
>>
>> @@ -481,8 +505,11 @@ int intel_plane_check_src_coordinates(struct
>> intel_plane_state *plane_state)
>>
>>  	I915_WRITE_FW(PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 0),
>>  		      PREOFF_YUV_TO_RGB_HI);
>> -	I915_WRITE_FW(PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1),
>> -		      PREOFF_YUV_TO_RGB_ME);
>> +	if (plane_state->base.color_range == DRM_COLOR_YCBCR_FULL_RANGE)
>> +		I915_WRITE_FW(PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1), 0);
>> +	else
>> +		I915_WRITE_FW(PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 1),
>> +			      PREOFF_YUV_TO_RGB_ME);
>
>I think this could probably be a separate patch since it affects
>BT.601/BT.709 as well. Oh, and the matrix coefficients for 601/709 seem similarly off
>as what you had in this patch originally. So I think we want yet another patch to fix
>those up. Just a bit surprised that even the current igts pass with those coefficients.

Sure, will split the same and resend. I agree BT601/709 has similar issue and was planning to
send a fixup patch for the same. I will investigate what is going on with IGT and how its
working fine.

>Anyways,
>Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com> (you can keep this on both
>patch if you split).

Thanks Ville.

>PS. pls. cc me @linux.intel.com rather than @intel.com. I generally ignore patches
>going to the @intel.com address. Not that I really care one way or the other whether
>a patch was cc:d to me anyway.

Sure, will add your linux.intel.com while cc'ing you :)

Regards,
Uma Shankar

>
>>  	I915_WRITE_FW(PLANE_INPUT_CSC_PREOFF(pipe, plane_id, 2),
>>  		      PREOFF_YUV_TO_RGB_LO);
>>  	I915_WRITE_FW(PLANE_INPUT_CSC_POSTOFF(pipe, plane_id, 0), 0x0);
>> --
>> 1.9.1
>>
>> _______________________________________________
>> Intel-gfx mailing list
>> Intel-gfx at lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
>--
>Ville Syrjälä
>Intel