Re: [PATCH v11 12/12] drm/mediatek: dpi: Add matrix_sel helper

[Rex-BC Chen <rex-bc.chen@mediatek.com>]

On Tue, 2022-06-14 at 14:20 +0800, CK Hu wrote:
> Hi, Bo-Chen:
> 
> On Mon, 2022-06-13 at 14:48 +0800, Bo-Chen Chen wrote:
> > From: Guillaume Ranquet <granquet@baylibre.com>
> > 
> > Add a mtk_dpi_matrix_sel() helper to update the DPI_MATRIX_SET
> > register depending on the color format.
> 
> Why set DPI_MATRIX_SET? New feature or bug fix? What does this matrix
> work for?
> 
> Regards,
> CK
> 

Matrix selection is a new feature for both dpi and dpintf of MT8195.
I will add this in next version.

> > 
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> > Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_dpi.c      | 21 +++++++++++++++++++++
> >  drivers/gpu/drm/mediatek/mtk_dpi_regs.h |  3 +++
> >  2 files changed, 24 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c
> > b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > index 9668bd5dd14a..dc355a512963 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > @@ -387,6 +387,25 @@ static void mtk_dpi_config_disable_edge(struct
> > mtk_dpi *dpi)
> >  		mtk_dpi_mask(dpi, dpi->conf->reg_h_fre_con, 0,
> > EDGE_SEL_EN);
> >  }
> >  
> > +static void mtk_dpi_matrix_sel(struct mtk_dpi *dpi, enum
> > mtk_dpi_out_color_format format)
> > +{
> > +	u32 matrix_sel = 0;
> > +
> > +	switch (format) {
> > +	case MTK_DPI_COLOR_FORMAT_YCBCR_422:
> > +	case MTK_DPI_COLOR_FORMAT_YCBCR_422_FULL:
> > +	case MTK_DPI_COLOR_FORMAT_YCBCR_444:
> > +	case MTK_DPI_COLOR_FORMAT_YCBCR_444_FULL:
> > +	case MTK_DPI_COLOR_FORMAT_XV_YCC:
> > +		if (dpi->mode.hdisplay <= 720)
> > +			matrix_sel = 0x2;
> > +		break;
> > +	default:
> > +		break;
> > +	}
> > +	mtk_dpi_mask(dpi, DPI_MATRIX_SET, matrix_sel,
> > INT_MATRIX_SEL_MASK);
> > +}
> > +
> >  static void mtk_dpi_config_color_format(struct mtk_dpi *dpi,
> >  					enum mtk_dpi_out_color_format
> > format)
> >  {
> > @@ -394,6 +413,7 @@ static void mtk_dpi_config_color_format(struct
> > mtk_dpi *dpi,
> >  	    (format == MTK_DPI_COLOR_FORMAT_YCBCR_444_FULL)) {
> >  		mtk_dpi_config_yuv422_enable(dpi, false);
> >  		mtk_dpi_config_csc_enable(dpi, true);
> > +		mtk_dpi_matrix_sel(dpi, format);
> >  		if (dpi->conf->swap_input_support)
> >  			mtk_dpi_config_swap_input(dpi, false);
> >  		mtk_dpi_config_channel_swap(dpi,
> > MTK_DPI_OUT_CHANNEL_SWAP_BGR);
> > @@ -401,6 +421,7 @@ static void mtk_dpi_config_color_format(struct
> > mtk_dpi *dpi,
> >  		   (format == MTK_DPI_COLOR_FORMAT_YCBCR_422_FULL)) {
> >  		mtk_dpi_config_yuv422_enable(dpi, true);
> >  		mtk_dpi_config_csc_enable(dpi, true);
> > +		mtk_dpi_matrix_sel(dpi, format);
> >  		if (dpi->conf->swap_input_support)
> >  			mtk_dpi_config_swap_input(dpi, true);
> >  		mtk_dpi_config_channel_swap(dpi,
> > MTK_DPI_OUT_CHANNEL_SWAP_RGB);
> > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi_regs.h
> > b/drivers/gpu/drm/mediatek/mtk_dpi_regs.h
> > index f7f0272dbd6a..96c117202d0d 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_dpi_regs.h
> > +++ b/drivers/gpu/drm/mediatek/mtk_dpi_regs.h
> > @@ -230,4 +230,7 @@
> >  #define EDGE_SEL_EN			BIT(5)
> >  #define H_FRE_2N			BIT(25)
> >  
> > +#define DPI_MATRIX_SET		0xB4
> > +#define INT_MATRIX_SEL_MASK	(0x1F << 0)
> > +
> >  #endif /* __MTK_DPI_REGS_H */
> 
>