Re: [PATCH v5 6/8] drm/mediatek: add matrix_bits private data for ccorr

[CK Hu <ck.hu@mediatek.com>]

Hi, Hsin-Yi:

On Mon, 2021-02-01 at 18:37 +0800, Hsin-Yi Wang wrote:
> From: Yongqiang Niu <yongqiang.niu@mediatek.com>
> 
> Add matrix_bits and coeffs_precision to ccorr private data:
> - matrix bits of mt8183 is 10
> - matrix bits of mt8192 is 11
> 
> Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_ccorr.c | 34 ++++++++++++++++-------
>  1 file changed, 24 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> index 6c86673a835c3..fb86f3a8b3a18 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> @@ -29,8 +29,10 @@
>  #define DISP_CCORR_COEF_3			0x008C
>  #define DISP_CCORR_COEF_4			0x0090
>  
> +#define CCORR_MATRIX_BITS			10
> +
>  struct mtk_disp_ccorr_data {
> -	u32 reserved;
> +	u32 matrix_bits;
>  };
>  
>  /**
> @@ -85,21 +87,22 @@ void mtk_ccorr_stop(struct device *dev)
>  	writel_relaxed(0x0, ccorr->regs + DISP_CCORR_EN);
>  }
>  
> -/* Converts a DRM S31.32 value to the HW S1.10 format. */
> -static u16 mtk_ctm_s31_32_to_s1_10(u64 in)
> +/* Converts a DRM S31.32 value to the HW S1.n format. */
> +static u16 mtk_ctm_s31_32_to_s1_n(u64 in, u32 n)
>  {
>  	u16 r;
>  
>  	/* Sign bit. */
> -	r = in & BIT_ULL(63) ? BIT(11) : 0;
> +	r = in & BIT_ULL(63) ? BIT(n + 1) : 0;
>  
>  	if ((in & GENMASK_ULL(62, 33)) > 0) {
> -		/* identity value 0x100000000 -> 0x400, */
> +		/* identity value 0x100000000 -> 0x400(mt8183), */
> +		/* identity value 0x100000000 -> 0x800(mt8192), */
>  		/* if bigger this, set it to max 0x7ff. */
> -		r |= GENMASK(10, 0);
> +		r |= GENMASK(n, 0);
>  	} else {
> -		/* take the 11 most important bits. */
> -		r |= (in >> 22) & GENMASK(10, 0);
> +		/* take the n+1 most important bits. */
> +		r |= (in >> (32 - n)) & GENMASK(n, 0);
>  	}
>  
>  	return r;
> @@ -114,6 +117,7 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
>  	uint16_t coeffs[9] = { 0 };
>  	int i;
>  	struct cmdq_pkt *cmdq_pkt = NULL;
> +	u32 matrix_bits;
>  
>  	if (!blob)
>  		return;
> @@ -121,8 +125,13 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
>  	ctm = (struct drm_color_ctm *)blob->data;
>  	input = ctm->matrix;
>  
> +	if (ccorr->data)

ccorr->data is always true, isn't it?

> +		matrix_bits = ccorr->data->matrix_bits;
> +	else
> +		matrix_bits = CCORR_MATRIX_BITS;
> +
>  	for (i = 0; i < ARRAY_SIZE(coeffs); i++)
> -		coeffs[i] = mtk_ctm_s31_32_to_s1_10(input[i]);
> +		coeffs[i] = mtk_ctm_s31_32_to_s1_n(input[i], matrix_bits);
>  
>  	mtk_ddp_write(cmdq_pkt, coeffs[0] << 16 | coeffs[1],
>  		      &ccorr->cmdq_reg, ccorr->regs, DISP_CCORR_COEF_0);
> @@ -199,8 +208,13 @@ static int mtk_disp_ccorr_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static const struct mtk_disp_ccorr_data mt8183_ccorr_driver_data = {
> +	.matrix_bits = CCORR_MATRIX_BITS,

Drop CCORR_MATRIX_BITS and use 10 here.

> +};
> +
>  static const struct of_device_id mtk_disp_ccorr_driver_dt_match[] = {
> -	{ .compatible = "mediatek,mt8183-disp-ccorr"},
> +	{ .compatible = "mediatek,mt8183-disp-ccorr",
> +	  .data = &mt8183_ccorr_driver_data},
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, mtk_disp_ccorr_driver_dt_match);