Re: [PATCH 2/2] drm/amd/display: use translate_curve_to_degamma_hw_format on DCN30

[Alex Hung <alex.hung@amd.com>]

On 8/19/26 10:00, Melissa Wen wrote:
> DCN3.01 presents the same banding issue as reported in the link below,

This affects more than just DCN301 as below:

drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_init.c: .set_blend_lut = 
dcn30_set_blend_lut,
drivers/gpu/drm/amd/display/dc/hwss/dcn301/dcn301_init.c: 
.set_blend_lut = dcn30_set_blend_lut,
drivers/gpu/drm/amd/display/dc/hwss/dcn31/dcn31_init.c: .set_blend_lut = 
dcn30_set_blend_lut,
drivers/gpu/drm/amd/display/dc/hwss/dcn314/dcn314_init.c: 
.set_blend_lut = dcn30_set_blend_lut,

> but the previous fix doesn't cover this hw. Change the helper for
> degamma/blend curves for DCN30-based family.
> 
> Link: https://lore.kernel.org/amd-gfx/20260623160112.1636801-1-mwen@igalia.com/
> Fixes: 3719314af322 ("drm/amd/display: use a separate helper to translate degamma curves")
> Signed-off-by: Melissa Wen <mwen@igalia.com>
> ---
>   .../gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c    | 10 ++++------
>   1 file changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
> index cb163902e12e..6980f622db0a 100644
> --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
> +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c
> @@ -243,10 +243,9 @@ bool dcn30_set_blend_lut(
>   	if (plane_state->cm.blend_func.type == TF_TYPE_HWPWL)
>   		blend_lut = &plane_state->cm.blend_func.pwl;
>   	else if (plane_state->cm.blend_func.type == TF_TYPE_DISTRIBUTED_POINTS) {
> -		result = cm3_helper_translate_curve_to_hw_format(plane_state->ctx,
> +		result = cm3_helper_translate_curve_to_degamma_hw_format(
>   				&plane_state->cm.blend_func,
> -				&dpp_base->regamma_params,
> -				false);
> +				&dpp_base->regamma_params);
>   		if (!result)
>   			return result;
>   
> @@ -337,9 +336,8 @@ bool dcn30_set_input_transfer_func(struct dc *dc,
>   	if (plane_state->in_transfer_func.type == TF_TYPE_HWPWL)
>   		params = &plane_state->in_transfer_func.pwl;
>   	else if (plane_state->in_transfer_func.type == TF_TYPE_DISTRIBUTED_POINTS &&
> -		cm3_helper_translate_curve_to_hw_format(plane_state->ctx,
> -							&plane_state->in_transfer_func,
> -							&dpp_base->degamma_params, false))
> +		cm3_helper_translate_curve_to_degamma_hw_format(&plane_state->in_transfer_func,
> +								&dpp_base->degamma_params))
>   		params = &dpp_base->degamma_params;
>   
>   	result = dpp_base->funcs->dpp_program_gamcor_lut(dpp_base, params);