Re: [PATCH v3 4/9] drm/mediatek: Add gamma support different lut_size for other SoC

[AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>]

Il 11/09/22 17:37, Jason-JH.Lin ha scritto:
> 1. Add mtk_drm_gamma_get_lut_size() and remove MTK_LUT_SIZE macro.
> 2. Add lut_size to gamma driver data for different SoC.
>
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> ---
>   drivers/gpu/drm/mediatek/mtk_disp_drv.h     |  1 +
>   drivers/gpu/drm/mediatek/mtk_disp_gamma.c   | 22 +++++++++++++++++++--
>   drivers/gpu/drm/mediatek/mtk_drm_crtc.c     |  4 ++--
>   drivers/gpu/drm/mediatek/mtk_drm_crtc.h     |  1 -
>   drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |  9 +++++++++
>   5 files changed, 32 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> index a83e5fbc8724..6a05bb56e693 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> @@ -51,6 +51,7 @@ void mtk_gamma_clk_disable(struct device *dev);
>   void mtk_gamma_config(struct device *dev, unsigned int w,
>   		      unsigned int h, unsigned int vrefresh,
>   		      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);
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> index f54a6a618348..e69d0b205b9a 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_gamma.c
> @@ -24,10 +24,12 @@
>   #define DISP_GAMMA_LUT				0x0700
>   
>   #define LUT_10BIT_MASK				0x03ff
> +#define LUT_SIZE_DEFAULT			512 /* for setting gamma lut from AAL */
>   
>   struct mtk_disp_gamma_data {
>   	bool has_dither;
>   	bool lut_diff;
> +	u16 lut_size;
>   };
>   
>   /*
> @@ -54,18 +56,32 @@ void mtk_gamma_clk_disable(struct device *dev)
>   	clk_disable_unprepare(gamma->clk);
>   }
>   
> +unsigned int mtk_gamma_get_size(struct device *dev)
> +{
> +	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
> +	unsigned int lut_size = LUT_SIZE_DEFAULT;
> +
> +	if (gamma && gamma->data)
> +		lut_size = gamma->data->lut_size;
> +
> +	return lut_size;
> +}
> +
>   void mtk_gamma_set_common(struct device *dev, void __iomem *regs, struct drm_crtc_state *state)
>   {
>   	struct mtk_disp_gamma *gamma = dev_get_drvdata(dev);
>   	bool lut_diff = false;
> +	u16 lut_size = LUT_SIZE_DEFAULT;

This makes us get a double assignment in case gamma->data is populated.

>   	unsigned int i, reg;
>   	struct drm_color_lut *lut;
>   	void __iomem *lut_base;
>   	u32 word;
>   	u32 diff[3] = {0};
>   
> -	if (gamma && gamma->data)
> +	if (gamma && gamma->data) {
>   		lut_diff = gamma->data->lut_diff;
> +		lut_size = gamma->data->lut_size;
> +	}

...you can avoid it like that:

} else {
	lut_size = LUT_SIZE_DEFAULT;
}


Regards,
Angelo