Re: [PATCH v3 18/21] drm/msm/dpu: Implement 10-bit color alpha for v12.0 DPU

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 21/02/2025 17:25, Dmitry Baryshkov wrote:
>> -static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,
>> -		struct dpu_plane_state *pstate, const struct msm_format *format)
>> +static void _dpu_crtc_setup_blend_cfg(const struct dpu_hw_ctl *ctl,
>> +				      struct dpu_crtc_mixer *mixer,
>> +				      struct dpu_plane_state *pstate,
>> +				      const struct msm_format *format)
>>  {
>>  	struct dpu_hw_mixer *lm = mixer->hw_lm;
>>  	uint32_t blend_op;
>> -	uint32_t fg_alpha, bg_alpha;
>> +	uint32_t fg_alpha, bg_alpha, max_alpha;
>>  
>>  	fg_alpha = pstate->base.alpha >> 8;
>> -	bg_alpha = 0xff - fg_alpha;
>> +	if (ctl->mdss_ver->core_major_ver < 12)
>> +		max_alpha = 0xff;
>> +	else
>> +		max_alpha = 0x3ff;
> 
> So, CTL is passed only to get struct dpu_mdss_version? It can either be
> passed directly or fetched via dpu_kms->catalog->mdss_ver

Ack.

> 
>> +	bg_alpha = max_alpha - fg_alpha;
>>  
>>  	/* default to opaque blending */
>>  	if (pstate->base.pixel_blend_mode == DRM_MODE_BLEND_PIXEL_NONE ||
>> @@ -337,7 +343,7 @@ static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,
>>  	} else if (pstate->base.pixel_blend_mode == DRM_MODE_BLEND_PREMULTI) {
>>  		blend_op = DPU_BLEND_FG_ALPHA_FG_CONST |
>>  			DPU_BLEND_BG_ALPHA_FG_PIXEL;
>> -		if (fg_alpha != 0xff) {
>> +		if (fg_alpha != max_alpha) {
>>  			bg_alpha = fg_alpha;
>>  			blend_op |= DPU_BLEND_BG_MOD_ALPHA |
>>  				    DPU_BLEND_BG_INV_MOD_ALPHA;
>> @@ -348,7 +354,7 @@ static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,
>>  		/* coverage blending */
>>  		blend_op = DPU_BLEND_FG_ALPHA_FG_PIXEL |
>>  			DPU_BLEND_BG_ALPHA_FG_PIXEL;
>> -		if (fg_alpha != 0xff) {
>> +		if (fg_alpha != max_alpha) {
>>  			bg_alpha = fg_alpha;
>>  			blend_op |= DPU_BLEND_FG_MOD_ALPHA |
>>  				    DPU_BLEND_FG_INV_MOD_ALPHA |
>> @@ -482,7 +488,7 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
>>  
>>  		/* blend config update */
>>  		for (lm_idx = 0; lm_idx < cstate->num_mixers; lm_idx++) {
>> -			_dpu_crtc_setup_blend_cfg(mixer + lm_idx, pstate, format);
>> +			_dpu_crtc_setup_blend_cfg(ctl, mixer + lm_idx, pstate, format);
>>  
>>  			if (bg_alpha_enable && !format->alpha_enable)
>>  				mixer[lm_idx].mixer_op_mode = 0;
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
>> index 3bfb61cb83672dca4236bdbbbfb1e442223576d2..75bf3521b03c8e243ccfe1fc226aa71f23b296df 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_lm.c
>> @@ -19,12 +19,20 @@
>>  
>>  /* These register are offset to mixer base + stage base */
>>  #define LM_BLEND0_OP                     0x00
>> +
>> +/* <v12 DPU with offset to mixer base + stage base */
>>  #define LM_BLEND0_CONST_ALPHA            0x04
>>  #define LM_FG_COLOR_FILL_COLOR_0         0x08
>>  #define LM_FG_COLOR_FILL_COLOR_1         0x0C
> 
> lowercase hex

Ack

> 
>>  #define LM_FG_COLOR_FILL_SIZE            0x10
>>  #define LM_FG_COLOR_FILL_XY              0x14
>>  
>> +/* >= v12 DPU */
>> +#define LM_BORDER_COLOR_0_V12		0x1C
> 
> lowercase hex
> 
>> +#define LM_BORDER_COLOR_1_V12		0x20
>> +
>> +/* >= v12 DPU with offset to mixer base + stage base */
>> +#define LM_BLEND0_CONST_ALPHA_V12	0x08
> 
> This doesn't seem to be aligned properly

That's only patch view... because I used tabs. I think existing code
uses spaces, so I will switch to spaces.


Best regards,
Krzysztof