Re: [PATCH v6,2/3] drm: mediatek: Adjust the dpi output format to MT8186

[CK Hu]

Hi, Xinlei:

On Wed, 2022-09-14 at 21:21 +0800, xinlei.lee@xxxxxxxxxxxx wrote:
> From: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> 
> Dpi output needs to adjust the output format to dual edge for MT8186.
> The bridge ic on MT8186 uses the output format of RGB888_dual_edge. 

I think different sink ic may support different output format, so query
the sink information to decide which outout format.

> Due
> to hardware changes, we need to modify the output format
> corresponding
> to the mmsys register.
> 
> Co-developed-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
> Signed-off-by: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@xxxxxxxxxxxxx>
> Reviewed-by: Nís F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/mediatek/mtk_dpi.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c
> b/drivers/gpu/drm/mediatek/mtk_dpi.c
> index fb0b79704636..6e02f02f163c 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> @@ -14,6 +14,7 @@
>  #include <linux/of_graph.h>
>  #include <linux/pinctrl/consumer.h>
>  #include <linux/platform_device.h>
> +#include <linux/soc/mediatek/mtk-mmsys.h>
>  #include <linux/types.h>
>  
>  #include <video/videomode.h>
> @@ -28,6 +29,7 @@
>  #include "mtk_disp_drv.h"
>  #include "mtk_dpi_regs.h"
>  #include "mtk_drm_ddp_comp.h"
> +#include "mtk_drm_drv.h"
>  
>  enum mtk_dpi_out_bit_num {
>  	MTK_DPI_OUT_BIT_NUM_8BITS,
> @@ -58,6 +60,11 @@ enum mtk_dpi_out_color_format {
>  	MTK_DPI_COLOR_FORMAT_YCBCR_422
>  };
>  
> +enum mtk_dpi_out_format_con {
> +	MTK_DPI_RGB888_DDR_CON,
> +	MTK_DPI_RGB565_SDR_CON
> +};
> +
>  struct mtk_dpi {
>  	struct drm_encoder encoder;
>  	struct drm_bridge bridge;
> @@ -80,6 +87,7 @@ struct mtk_dpi {
>  	struct pinctrl_state *pins_dpi;
>  	u32 output_fmt;
>  	int refcount;
> +	struct device *mmsys_dev;
>  };
>  
>  static inline struct mtk_dpi *bridge_to_dpi(struct drm_bridge *b)
> @@ -133,6 +141,7 @@ struct mtk_dpi_yc_limit {
>   * @yuv422_en_bit: Enable bit of yuv422.
>   * @csc_enable_bit: Enable bit of CSC.
>   * @pixels_per_iter: Quantity of transferred pixels per iteration.
> + * @edge_cfg_in_mmsys: If the edge configuration for DPI's output
> needs to be set in MMSYS.
>   */
>  struct mtk_dpi_conf {
>  	unsigned int (*cal_factor)(int clock);
> @@ -151,6 +160,7 @@ struct mtk_dpi_conf {
>  	u32 yuv422_en_bit;
>  	u32 csc_enable_bit;
>  	u32 pixels_per_iter;
> +	bool edge_cfg_in_mmsys;
>  };
>  
>  static void mtk_dpi_mask(struct mtk_dpi *dpi, u32 offset, u32 val,
> u32 mask)
> @@ -447,6 +457,8 @@ static void mtk_dpi_dual_edge(struct mtk_dpi
> *dpi)
>  		mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING,
>  			     dpi->output_fmt ==
> MEDIA_BUS_FMT_RGB888_2X12_LE ?
>  			     EDGE_SEL : 0, EDGE_SEL);
> +		if (dpi->conf->edge_cfg_in_mmsys)
> +			mtk_mmsys_ddp_dpi_fmt_config(dpi->mmsys_dev,
> MTK_DPI_RGB888_DDR_CON);

Why do you set a DPI driver defined value MTK_DPI_RGB888_DDR_CON into
mmsys driver? I think you should set a value which mmsys driver
understand.

Regards,
CK

>  	} else {
>  		mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE,
> 0);
>  	}
> @@ -776,8 +788,10 @@ static int mtk_dpi_bind(struct device *dev,
> struct device *master, void *data)
>  {
>  	struct mtk_dpi *dpi = dev_get_drvdata(dev);
>  	struct drm_device *drm_dev = data;
> +	struct mtk_drm_private *priv = drm_dev->dev_private;
>  	int ret;
>  
> +	dpi->mmsys_dev = priv->mmsys_dev;
>  	ret = drm_simple_encoder_init(drm_dev, &dpi->encoder,
>  				      DRM_MODE_ENCODER_TMDS);
>  	if (ret) {