[PATCH RESEND v3 7/9] drm/mediatek: Add gamma lut support for mt8195

[Jason-JH Lin]

Hi CK,

Thanks for the reviews.

On Mon, 2022-09-12 at 18:00 +0800, CK Hu wrote:
> Hi, Jason:
> 
> On Mon, 2022-09-12 at 09:30 +0800, Jason-JH.Lin wrote:
> > From: "zheng-yan.chen" <zheng-yan.chen at mediatek.com>
> > 
> > Since the previous gamma_set_common() function is designed for
> > 9bit-to-10bit conversion, which is not feasible for the
> > 10bit-to-12bit conversion in mt8195.
> > 
> > 1. Update the function to fit the need of mt8195.
> > 2. Add gamma driver data for mt8195.
> > 
> > Signed-off-by: zheng-yan.chen <zheng-yan.chen at mediatek.com>
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 57 ++++++++++++++++---
> > --
> > --
> >  1 file changed, 40 insertions(+), 17 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > index 45da2b6206c8..d706f76fd30e 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> > @@ -23,6 +23,7 @@
> >  #define DISP_GAMMA_SIZE				0x0030
> >  #define DISP_GAMMA_BANK				0x0100
> >  #define DISP_GAMMA_LUT				0x0700
> > +#define DISP_GAMMA_LUT1				0x0b00
> >  
> >  #define LUT_10BIT_MASK				0x03ff
> >  #define LUT_SIZE_DEFAULT			512 /* for setting
> > gamma lut from AAL */
> > @@ -82,9 +83,8 @@ void mtk_gamma_set_common(struct device *dev,
> > void
> > __iomem *regs, struct drm_crt
> >  	u8 shift_bits;
> >  	unsigned int i, j, reg, bank_num;
> >  	struct drm_color_lut *lut;
> > -	void __iomem *lut_base;
> > -	u32 word, mask;
> > -	u32 diff[3] = {0};
> > +	void __iomem *lut_base, *lut1_base;
> > +	u32 word, word1, mask;
> >  
> >  	if (gamma && gamma->data) {
> >  		lut_diff = gamma->data->lut_diff;
> > @@ -102,27 +102,41 @@ void mtk_gamma_set_common(struct device *dev,
> > void __iomem *regs, struct drm_crt
> >  		reg = reg | GAMMA_LUT_EN;
> >  		writel(reg, regs + DISP_GAMMA_CFG);
> >  		lut_base = regs + DISP_GAMMA_LUT;
> > +		lut1_base = regs + DISP_GAMMA_LUT1;
> >  		lut = (struct drm_color_lut *)state->gamma_lut->data;
> >  		for (j = 0; j < bank_num; j++) {
> >  			writel(j, regs + DISP_GAMMA_BANK);
> >  			for (i = 0; i < bank_size; i++) {
> > -				if (!lut_diff || (i % 2 == 0)) {
> > -					word = (((lut[i].red >>
> > shift_bits) & mask) << 20) +
> > -						(((lut[i].green >>
> > shift_bits) & mask) << 10) +
> > -						((lut[i].blue >>
> > shift_bits) & mask);
> > +				struct drm_color_lut input;
> > +
> > +				input.red = (lut[i].red >> shift_bits)
> > & mask;
> > +				input.green = (lut[i].green >>
> > shift_bits) & mask;
> > +				input.blue = (lut[i].blue >>
> > shift_bits) & mask;
> > +				if (!lut_diff || i % 2 == 0) {
> > +					word = (lut_bits == 12) ?
> 
> Move lut_bits modification to the patch "drm/mediatek: Add gamma
> support different lut_bits for other SoC".

OK, I'll move this.
> 
> > +					       (input.red +
> > (input.green << 12)) :
> > +					       ((input.red << 20) +
> > (input.green << 10) +
> > +						input.blue);
> > +					word1 = input.blue;
> >  				} else {
> > -					diff[0] = (lut[i].red >>
> > shift_bits) -
> > -						  (lut[i - 1].red >>
> > shift_bits);
> > -					diff[1] = (lut[i].green >>
> > shift_bits) -
> > -						  (lut[i - 1].green >>
> > shift_bits);
> > -					diff[2] = (lut[i].blue >>
> > shift_bits) -
> > -						  (lut[i - 1].blue >>
> > shift_bits);
> > -
> > -					word = ((diff[0] & mask) << 20)
> > +
> > -						((diff[1] & mask) <<
> > 10) +
> > -						(diff[2] & mask);
> > +					struct drm_color_lut diff;
> > +
> > +					diff.red = input.red  -
> > +						   ((lut[i - 1].red >>
> > shift_bits) & mask);
> > +					diff.green = input.green -
> > +						     ((lut[i - 1].green
> > > > shift_bits & mask));
> > 
> > +					diff.blue = input.blue -
> > +						    ((lut[i - 1].blue
> > > > shift_bits) & mask);
> > 
> > +
> > +					word = (lut_bits == 12) ?
> 
> Ditto.

OK, I'll move this.
> 
> > +					       (input.red +
> > (input.green << 12)) :
> > +					       (diff.red << 20) +
> > (diff.green << 10) + diff.blue;
> > +					word1 = input.blue;
> >  				}
> > +
> >  				writel(word, (lut_base + i * 4));
> > +				if (lut_bits == 12)
> 
> Ditto.

Because only mt8195 has lut1_base register, so I'll declare bool
12bit_mode = (lut_bits == 12) ? true : false; instead and move this to
the patch "drm/mediatek: Add gamma support different lut_bits for other
SoC".

Regards,
Jason-JH.Lin

> 
> Regards,
> CK
> 
> > +					writel(word1, (lut1_base + i *
> > 4));
> >  			}
> >  		}
> >  	}
> > @@ -237,11 +251,20 @@ static const struct mtk_disp_gamma_data
> > mt8183_gamma_driver_data = {
> >  	.lut_bits = 10,
> >  };
> >  
> > +static const struct mtk_disp_gamma_data mt8195_gamma_driver_data =
> > {
> > +	.lut_diff = true,
> > +	.lut_size = 512,
> > +	.lut_bits = 10,
> > +	.bank_size = 256,
> > +};
> > +
> >  static const struct of_device_id mtk_disp_gamma_driver_dt_match[]
> > =
> > {
> >  	{ .compatible = "mediatek,mt8173-disp-gamma",
> >  	  .data = &mt8173_gamma_driver_data},
> >  	{ .compatible = "mediatek,mt8183-disp-gamma",
> >  	  .data = &mt8183_gamma_driver_data},
> > +	{ .compatible = "mediatek,mt8195-disp-gamma",
> > +	  .data = &mt8195_gamma_driver_data},
> >  	{},
> >  };
> >  MODULE_DEVICE_TABLE(of, mtk_disp_gamma_driver_dt_match);
> 
> 
-- 
Jason-JH Lin <jason-jh.lin at mediatek.com>