Re: [PATCH v4 4/8] drm/mediatek: enable OVL_LAYER_SMI_ID_EN for multi-layer usecase

[CK Hu]

Hi, Hsin-Yi:

On Fri, 2021-01-29 at 15:34 +0800, Hsin-Yi Wang wrote:
> From: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
> 
> enable OVL_LAYER_SMI_ID_EN for multi-layer usecase, without this patch,
> ovl will hang up when more than 1 layer enabled.

Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx>

> 
> Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
> Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> index da7e38a28759b..961f87f8d4d15 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -24,6 +24,7 @@
>  #define DISP_REG_OVL_RST			0x0014
>  #define DISP_REG_OVL_ROI_SIZE			0x0020
>  #define DISP_REG_OVL_DATAPATH_CON		0x0024
> +#define OVL_LAYER_SMI_ID_EN				BIT(0)
>  #define OVL_BGCLR_SEL_IN				BIT(2)
>  #define DISP_REG_OVL_ROI_BGCLR			0x0028
>  #define DISP_REG_OVL_SRC_CON			0x002c
> @@ -62,6 +63,7 @@ struct mtk_disp_ovl_data {
>  	unsigned int gmc_bits;
>  	unsigned int layer_nr;
>  	bool fmt_rgb565_is_0;
> +	bool smi_id_en;
>  };
>  
>  /**
> @@ -134,6 +136,13 @@ void mtk_ovl_start(struct device *dev)
>  {
>  	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
>  
> +	if (ovl->data->smi_id_en) {
> +		unsigned int reg;
> +
> +		reg = readl(ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> +		reg = reg | OVL_LAYER_SMI_ID_EN;
> +		writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> +	}
>  	writel_relaxed(0x1, ovl->regs + DISP_REG_OVL_EN);
>  }
>  
> @@ -142,6 +151,14 @@ void mtk_ovl_stop(struct device *dev)
>  	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
>  
>  	writel_relaxed(0x0, ovl->regs + DISP_REG_OVL_EN);
> +	if (ovl->data->smi_id_en) {
> +		unsigned int reg;
> +
> +		reg = readl(ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> +		reg = reg & ~OVL_LAYER_SMI_ID_EN;
> +		writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
> +	}
> +
>  }
>  
>  void mtk_ovl_config(struct device *dev, unsigned int w,