Re: [v2 2/5] drm/mediatek: CMDQ reg address of mt8173 is different with mt2701

[CK Hu]

On Tue, 2019-04-16 at 14:04 +0800, Jitao Shi wrote:
> Config the different CMDQ reg address in driver data.
> 
For MT8173, you change reg_cmd_off from 0x180 to 0x200, so this patch is
a bug fix. You should add a 'Fixes' tag.

> Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 39 +++++++++++++++++++++++-------
>  1 file changed, 30 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 6c4ac37f983d..573e6bec6d36 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -131,7 +131,6 @@
>  #define VM_CMD_EN			BIT(0)
>  #define TS_VFP_EN			BIT(5)
>  
> -#define DSI_CMDQ0		0x180
>  #define CONFIG				(0xff << 0)
>  #define SHORT_PACKET			0
>  #define LONG_PACKET			2
> @@ -156,6 +155,10 @@
>  
>  struct phy;
>  
> +struct mtk_dsi_driver_data {
> +	const u32 reg_cmdq_off;
> +};
> +
>  struct mtk_dsi {
>  	struct mtk_ddp_comp ddp_comp;
>  	struct device *dev;
> @@ -182,6 +185,7 @@ struct mtk_dsi {
>  	bool enabled;
>  	u32 irq_data;
>  	wait_queue_head_t irq_wait_queue;
> +	struct mtk_dsi_driver_data *driver_data;
>  };
>  
>  static inline struct mtk_dsi *encoder_to_dsi(struct drm_encoder *e)
> @@ -934,6 +938,7 @@ static void mtk_dsi_cmdq(struct mtk_dsi *dsi, const struct mipi_dsi_msg *msg)
>  	const char *tx_buf = msg->tx_buf;
>  	u8 config, cmdq_size, cmdq_off, type = msg->type;
>  	u32 reg_val, cmdq_mask, i;
> +	u32 reg_cmdq_off = dsi->driver_data->reg_cmdq_off;
>  
>  	if (MTK_DSI_HOST_IS_READ(type))
>  		config = BTA;
> @@ -953,9 +958,11 @@ static void mtk_dsi_cmdq(struct mtk_dsi *dsi, const struct mipi_dsi_msg *msg)
>  	}
>  
>  	for (i = 0; i < msg->tx_len; i++)
> -		writeb(tx_buf[i], dsi->regs + DSI_CMDQ0 + cmdq_off + i);
> +		mtk_dsi_mask(dsi, (reg_cmdq_off + cmdq_off + i) & (~0x3U),
> +			     (0xffUL << (((i + cmdq_off) & 3U) * 8U)),
> +			     tx_buf[i] << (((i + cmdq_off) & 3U) * 8U));

You say you would follow Nicolas' suggestion here.

>  
> -	mtk_dsi_mask(dsi, DSI_CMDQ0, cmdq_mask, reg_val);
> +	mtk_dsi_mask(dsi, reg_cmdq_off, cmdq_mask, reg_val);
>  	mtk_dsi_mask(dsi, DSI_CMDQ_SIZE, CMDQ_SIZE, cmdq_size);
>  }
>  
> @@ -1074,10 +1081,27 @@ static const struct component_ops mtk_dsi_component_ops = {
>  	.unbind = mtk_dsi_unbind,
>  };
>  
> +static const struct mtk_dsi_driver_data mt8173_dsi_driver_data = {
> +	.reg_cmdq_off = 0x200,
> +};
> +
> +static const struct mtk_dsi_driver_data mt2701_dsi_driver_data = {
> +	.reg_cmdq_off = 0x180,
> +};
> +
> +static const struct of_device_id mtk_dsi_of_match[] = {
> +	{ .compatible = "mediatek,mt2701-dsi",
> +	  .data = &mt2701_dsi_driver_data },
> +	{ .compatible = "mediatek,mt8173-dsi",
> +	  .data = &mt8173_dsi_driver_data },
> +	{ },
> +};
> +
>  static int mtk_dsi_probe(struct platform_device *pdev)
>  {
>  	struct mtk_dsi *dsi;
>  	struct device *dev = &pdev->dev;
> +	const struct of_device_id *of_id;
>  	struct resource *regs;
>  	int irq_num;
>  	int comp_id;
> @@ -1101,6 +1125,9 @@ static int mtk_dsi_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto err_unregister_host;
>  
> +	of_id = of_match_device(mtk_dsi_of_match, &pdev->dev);
> +	dsi->driver_data = of_id->data;

Maybe use of_device_get_match_data() is a more simple way. You could
refer to [1].

[1]
https://elixir.bootlin.com/linux/v5.1/source/drivers/gpu/drm/mediatek/mtk_disp_ovl.c#L300

Regards,
CK

> +
>  	dsi->engine_clk = devm_clk_get(dev, "engine");
>  	if (IS_ERR(dsi->engine_clk)) {
>  		ret = PTR_ERR(dsi->engine_clk);
> @@ -1193,12 +1220,6 @@ static int mtk_dsi_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static const struct of_device_id mtk_dsi_of_match[] = {
> -	{ .compatible = "mediatek,mt2701-dsi" },
> -	{ .compatible = "mediatek,mt8173-dsi" },
> -	{ },
> -};
> -
>  struct platform_driver mtk_dsi_driver = {
>  	.probe = mtk_dsi_probe,
>  	.remove = mtk_dsi_remove,