Re: [PATCH v10 08/16] drm/mediatek: De-commonize disp_aal/disp_gamma gamma_set functions

["CK Hu (胡俊光)" <ck.hu@mediatek.com>]

Hi, Angelo:

On Fri, 2023-08-04 at 09:28 +0200, AngeloGioacchino Del Regno wrote:
> In preparation for adding a 12-bits gamma support for the DISP_GAMMA
> IP, remove the mtk_gamma_set_common() function and move the relevant
> bits in mtk_gamma_set() for DISP_GAMMA and mtk_aal_gamma_set() for
> DISP_AAL: since the latter has no more support for gamma manipulation
> (being moved to a different IP) in newer revisions, those functions
> are about to diverge and it makes no sense to keep a common one (with
> all the complications of passing common data and making exclusions
> for device driver data) for just a few bits.
> 
> This commit brings no functional changes.
> 
> Signed-off-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_aal.c   | 39
> +++++++++++++++++++++--
>  drivers/gpu/drm/mediatek/mtk_disp_drv.h   |  1 -
>  drivers/gpu/drm/mediatek/mtk_disp_gamma.c | 34 ++++----------------
>  3 files changed, 44 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_aal.c
> b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
> index bec035780db0..21b25470e9b7 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_aal.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_aal.c
> @@ -17,10 +17,18 @@
>  
>  #define DISP_AAL_EN				0x0000
>  #define AAL_EN						BIT(0)
> +#define DISP_AAL_CFG				0x0020
> +#define AAL_RELAY_MODE					BIT(0)

You does not use this bit in this patch, so move it to [12/16].

> +#define AAL_GAMMA_LUT_EN				BIT(1)

You should enable this bit.

>  #define DISP_AAL_SIZE				0x0030
>  #define DISP_AAL_SIZE_HSIZE				GENMASK(28, 16)
>  #define DISP_AAL_SIZE_VSIZE				GENMASK(12, 0)
>  #define DISP_AAL_OUTPUT_SIZE			0x04d8
> +#define DISP_AAL_GAMMA_LUT			0x0700
> +#define DISP_AAL_GAMMA_LUT_R				GENMASK(29, 20)
> +#define DISP_AAL_GAMMA_LUT_G				GENMASK(19, 10)
> +#define DISP_AAL_GAMMA_LUT_B				GENMASK(9, 0)
> +#define DISP_AAL_LUT_BITS			10
>  #define DISP_AAL_LUT_SIZE			512
>  
>  struct mtk_disp_aal_data {
> @@ -85,9 +93,36 @@ unsigned int mtk_aal_gamma_get_lut_size(struct
> device *dev)
>  void mtk_aal_gamma_set(struct device *dev, struct drm_crtc_state
> *state)
>  {
>  	struct mtk_disp_aal *aal = dev_get_drvdata(dev);
> +	struct drm_color_lut *lut;
> +	unsigned int i;
> +	u32 cfg_val;
> +
> +	/* If gamma is not supported in AAL, go out immediately */
> +	if (!(aal->data && aal->data->has_gamma))
> +		return;
> +
> +	/* Also, if there's no gamma lut there's nothing to do here. */
> +	if (!state->gamma_lut)
> +		return;
> +
> +	cfg_val = readl(aal->regs + DISP_AAL_CFG);
> +	lut = (struct drm_color_lut *)state->gamma_lut->data;
> +
> +	for (i = 0; i < DISP_AAL_LUT_SIZE; i++) {
> +		struct drm_color_lut hwlut = {
> +			.red = drm_color_lut_extract(lut[i].red,
> DISP_AAL_LUT_BITS),
> +			.green = drm_color_lut_extract(lut[i].green,
> DISP_AAL_LUT_BITS),
> +			.blue = drm_color_lut_extract(lut[i].blue,
> DISP_AAL_LUT_BITS)
> +		};
> +		u32 word;
> +
> +		word = FIELD_PREP(DISP_AAL_GAMMA_LUT_R, hwlut.red);
> +		word |= FIELD_PREP(DISP_AAL_GAMMA_LUT_G, hwlut.green);
> +		word |= FIELD_PREP(DISP_AAL_GAMMA_LUT_B, hwlut.blue);
> +		writel(word, (aal->regs + DISP_AAL_GAMMA_LUT) + (i *
> 4));

This could be more simple:

writel(word, aal->regs + DISP_AAL_GAMMA_LUT + i * 4);

Regards,
CK

> +	}
>  
> -	if (aal->data && aal->data->has_gamma)
> -		mtk_gamma_set_common(NULL, aal->regs, state);
> +	writel(cfg_val, aal->regs + DISP_AAL_CFG);
>  }
>  
>  void mtk_aal_start(struct device *dev)
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> index ca377265e5eb..54d3712e2afd 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> @@ -56,7 +56,6 @@ void mtk_gamma_config(struct device *dev, unsigned
> int w,
>  		      unsigned int bpc, struct cmdq_pkt *cmdq_pkt);
>  unsigned int mtk_gamma_get_lut_size(struct device *dev);
>  void mtk_gamma_set(struct device *dev, struct drm_crtc_state
> *state);
> -void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
> struct drm_crtc_state *state);
>  void mtk_gamma_start(struct device *dev);
>  void mtk_gamma_stop(struct device *dev);
>  
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> index ea91d3619716..001b98694761 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> @@ -73,42 +73,29 @@ unsigned int mtk_gamma_get_lut_size(struct device
> *dev)
>  	return LUT_SIZE_DEFAULT;
>  }
>  
> -void mtk_gamma_set_common(struct device *dev, void __iomem *regs,
> struct drm_crtc_state *state)
> +void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
>  {
> -	struct mtk_disp_gamma *gamma;
> +	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
>  	unsigned int i;
>  	struct drm_color_lut *lut;
>  	void __iomem *lut_base;
> -	bool lut_diff;
> -	u16 lut_size;
>  	u32 cfg_val, word;
>  
>  	/* If there's no gamma lut there's nothing to do here. */
>  	if (!state->gamma_lut)
>  		return;
>  
> -	/* If we're called from AAL, dev is NULL */
> -	gamma = dev ? dev_get_drvdata(dev) : NULL;
> -
> -	if (gamma && gamma->data) {
> -		lut_diff = gamma->data->lut_diff;
> -		lut_size = gamma->data->lut_size;
> -	} else {
> -		lut_diff = false;
> -		lut_size = LUT_SIZE_DEFAULT;
> -	}
> -
> -	cfg_val = readl(regs + DISP_GAMMA_CFG);
> -	lut_base = regs + DISP_GAMMA_LUT;
> +	cfg_val = readl(gamma->regs + DISP_GAMMA_CFG);
> +	lut_base = gamma->regs + DISP_GAMMA_LUT;
>  	lut = (struct drm_color_lut *)state->gamma_lut->data;
> -	for (i = 0; i < lut_size; i++) {
> +	for (i = 0; i < gamma->data->lut_size; i++) {
>  		struct drm_color_lut diff, hwlut;
>  
>  		hwlut.red = drm_color_lut_extract(lut[i].red,
> LUT_BITS_DEFAULT);
>  		hwlut.green = drm_color_lut_extract(lut[i].green,
> LUT_BITS_DEFAULT);
>  		hwlut.blue = drm_color_lut_extract(lut[i].blue,
> LUT_BITS_DEFAULT);
>  
> -		if (!lut_diff || (i % 2 == 0)) {
> +		if (!gamma->data->lut_diff || (i % 2 == 0)) {
>  			word = FIELD_PREP(DISP_GAMMA_LUT_10BIT_R,
> hwlut.red);
>  			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_G,
> hwlut.green);
>  			word |= FIELD_PREP(DISP_GAMMA_LUT_10BIT_B,
> hwlut.blue);
> @@ -132,14 +119,7 @@ void mtk_gamma_set_common(struct device *dev,
> void __iomem *regs, struct drm_crt
>  	/* Enable the gamma table */
>  	cfg_val |= FIELD_PREP(GAMMA_LUT_EN, 1);
>  
> -	writel(cfg_val, regs + DISP_GAMMA_CFG);
> -}
> -
> -void mtk_gamma_set(struct device *dev, struct drm_crtc_state *state)
> -{
> -	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
> -
> -	mtk_gamma_set_common(dev, gamma->regs, state);
> +	writel(cfg_val, gamma->regs + DISP_GAMMA_CFG);
>  }
>  
>  void mtk_gamma_config(struct device *dev, unsigned int w,