[v3,4/4] drm: lcdif: Add support for YUV planes

Commit Message

Laurent Pinchart Sept. 29, 2022, 8:42 p.m. UTC

From: Kieran Bingham <[e-mail]>

The LCDIF includes a color space converter that supports YUV input. Use
it to support YUV planes, either through the converter if the output
format is RGB, or in conversion bypass mode otherwise.

Signed-off-by: Kieran Bingham <[e-mail]>
Signed-off-by: Laurent Pinchart <[e-mail]>
Reviewed-by: Marek Vasut <[e-mail]>
Reviewed-by: Kieran Bingham <[e-mail]>
---
Changes since v2:

- Fix YUV to RGB coefficients
- List floating point coefficient values in comment
- Express CSC coefficients with three hex digits
- Move | to the end of the line
- Add comment header before RGB formats

Changes since v1:

- Support all YCbCr encodings and quantization ranges
- Drop incorrect comment
---
 drivers/gpu/drm/mxsfb/lcdif_kms.c  | 260 ++++++++++++++++++++++++-----
 drivers/gpu/drm/mxsfb/lcdif_regs.h |   5 +-
 2 files changed, 224 insertions(+), 41 deletions(-)

Comments

Liu Ying Sept. 30, 2022, 4:01 a.m. UTC | #1

Hi Laurent,

On Thu, 2022-09-29 at 23:42 +0300, Laurent Pinchart wrote:
> From: Kieran Bingham <[e-mail]>
> 
> The LCDIF includes a color space converter that supports YUV input. Use
> it to support YUV planes, either through the converter if the output
> format is RGB, or in conversion bypass mode otherwise.
> 
> Signed-off-by: Kieran Bingham <[e-mail]>
> Signed-off-by: Laurent Pinchart <[e-mail]>
> Reviewed-by: Marek Vasut <[e-mail]>
> Reviewed-by: Kieran Bingham <[e-mail]>
> ---
> Changes since v2:
> 
> - Fix YUV to RGB coefficients
> - List floating point coefficient values in comment
> - Express CSC coefficients with three hex digits
> - Move | to the end of the line
> - Add comment header before RGB formats
> 
> Changes since v1:
> 
> - Support all YCbCr encodings and quantization ranges
> - Drop incorrect comment
> ---
>  drivers/gpu/drm/mxsfb/lcdif_kms.c  | 260 ++++++++++++++++++++++++-----
>  drivers/gpu/drm/mxsfb/lcdif_regs.h |   5 +-
>  2 files changed, 224 insertions(+), 41 deletions(-)

Hmmm, 'git am' fails to apply this one to drm-misc-next but it's ok
with v6.0-rc1.  I should have tried drm-misc-next with v2.

> 
> diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> index 08e4880ec6cf..81454b53936f 100644
> --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> @@ -15,6 +15,7 @@
>  #include <drm/drm_atomic.h>
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_bridge.h>
> +#include <drm/drm_color_mgmt.h>
>  #include <drm/drm_crtc.h>
>  #include <drm/drm_encoder.h>
>  #include <drm/drm_framebuffer.h>
> @@ -32,13 +33,119 @@
>  /* -----------------------------------------------------------------------------
>   * CRTC
>   */
> +
> +/*
> + * Despite the reference manual stating the opposite, the D1, D2 and D3 offset
> + * values are added to Y, U and V, not subtracted. They must thus be programmed
> + * with negative values.

Can you add the generic conversion equations with [A-D][1-3]
coefficient symbols as comments in code, like imx-pxp.c does?  It will
improve code readability better and tell which coefficient is which.
Also for RGB to YCbCr conversion if you want to do that with this
series.  Sorry for not pointing this out in v2 review cycle.

> + */
> +static const u32 lcdif_yuv2rgb_coeffs[3][2][6] = {

[...]

> +	/* YUYV Formats */

'YUV Formats' would be better?  Again, failed to catch this in v2...

Regards,
Liu Ying

> +	case DRM_FORMAT_YUYV:
> +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_VY2UY1,
> +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> +		in_yuv = true;
> +		break;
> +	case DRM_FORMAT_YVYU:
> +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_UY2VY1,
> +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> +		in_yuv = true;
> +		break;
> +	case DRM_FORMAT_UYVY:
> +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2VY1U,
> +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> +		in_yuv = true;
> +		break;
> +	case DRM_FORMAT_VYUY:
> +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2UY1V,
> +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> +		in_yuv = true;
> +		break;
> +
> +	default:
> +		dev_err(drm->dev, "Unknown pixel format 0x%x\n", format);
> +		break;
> +	}

Laurent Pinchart Sept. 30, 2022, 8:05 a.m. UTC | #2

Hi Liu,

On Fri, Sep 30, 2022 at 12:01:39PM +0800, Liu Ying wrote:
> On Thu, 2022-09-29 at 23:42 +0300, Laurent Pinchart wrote:
> > From: Kieran Bingham <[e-mail]>
> > 
> > The LCDIF includes a color space converter that supports YUV input. Use
> > it to support YUV planes, either through the converter if the output
> > format is RGB, or in conversion bypass mode otherwise.
> > 
> > Signed-off-by: Kieran Bingham <[e-mail]>
> > Signed-off-by: Laurent Pinchart <[e-mail]>
> > Reviewed-by: Marek Vasut <[e-mail]>
> > Reviewed-by: Kieran Bingham <[e-mail]>
> > ---
> > Changes since v2:
> > 
> > - Fix YUV to RGB coefficients
> > - List floating point coefficient values in comment
> > - Express CSC coefficients with three hex digits
> > - Move | to the end of the line
> > - Add comment header before RGB formats
> > 
> > Changes since v1:
> > 
> > - Support all YCbCr encodings and quantization ranges
> > - Drop incorrect comment
> > ---
> >  drivers/gpu/drm/mxsfb/lcdif_kms.c  | 260 ++++++++++++++++++++++++-----
> >  drivers/gpu/drm/mxsfb/lcdif_regs.h |   5 +-
> >  2 files changed, 224 insertions(+), 41 deletions(-)
> 
> Hmmm, 'git am' fails to apply this one to drm-misc-next but it's ok
> with v6.0-rc1.  I should have tried drm-misc-next with v2.

Oops. I'll rebase on top of drm-misc-next.

> > diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > index 08e4880ec6cf..81454b53936f 100644
> > --- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > +++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
> > @@ -15,6 +15,7 @@
> >  #include <drm/drm_atomic.h>
> >  #include <drm/drm_atomic_helper.h>
> >  #include <drm/drm_bridge.h>
> > +#include <drm/drm_color_mgmt.h>
> >  #include <drm/drm_crtc.h>
> >  #include <drm/drm_encoder.h>
> >  #include <drm/drm_framebuffer.h>
> > @@ -32,13 +33,119 @@
> >  /* -----------------------------------------------------------------------------
> >   * CRTC
> >   */
> > +
> > +/*
> > + * Despite the reference manual stating the opposite, the D1, D2 and D3 offset
> > + * values are added to Y, U and V, not subtracted. They must thus be programmed
> > + * with negative values.
> 
> Can you add the generic conversion equations with [A-D][1-3]
> coefficient symbols as comments in code, like imx-pxp.c does?  It will
> improve code readability better and tell which coefficient is which.
> Also for RGB to YCbCr conversion if you want to do that with this
> series.  Sorry for not pointing this out in v2 review cycle.

I'll fix that.

> > + */
> > +static const u32 lcdif_yuv2rgb_coeffs[3][2][6] = {
> 
> [...]
> 
> > +	/* YUYV Formats */
> 
> 'YUV Formats' would be better?  Again, failed to catch this in v2...

Will fix this too.

> > +	case DRM_FORMAT_YUYV:
> > +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_VY2UY1,
> > +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> > +		in_yuv = true;
> > +		break;
> > +	case DRM_FORMAT_YVYU:
> > +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_UY2VY1,
> > +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> > +		in_yuv = true;
> > +		break;
> > +	case DRM_FORMAT_UYVY:
> > +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2VY1U,
> > +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> > +		in_yuv = true;
> > +		break;
> > +	case DRM_FORMAT_VYUY:
> > +		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2UY1V,
> > +		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
> > +		in_yuv = true;
> > +		break;
> > +
> > +	default:
> > +		dev_err(drm->dev, "Unknown pixel format 0x%x\n", format);
> > +		break;
> > +	}

Patch

diff --git a/drivers/gpu/drm/mxsfb/lcdif_kms.c b/drivers/gpu/drm/mxsfb/lcdif_kms.c
index 08e4880ec6cf..81454b53936f 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_kms.c
+++ b/drivers/gpu/drm/mxsfb/lcdif_kms.c
@@ -15,6 +15,7 @@ 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_bridge.h>
+#include <drm/drm_color_mgmt.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_encoder.h>
 #include <drm/drm_framebuffer.h>
@@ -32,13 +33,119 @@ 
 /* -----------------------------------------------------------------------------
  * CRTC
  */
+
+/*
+ * Despite the reference manual stating the opposite, the D1, D2 and D3 offset
+ * values are added to Y, U and V, not subtracted. They must thus be programmed
+ * with negative values.
+ */
+static const u32 lcdif_yuv2rgb_coeffs[3][2][6] = {
+	[DRM_COLOR_YCBCR_BT601] = {
+		[DRM_COLOR_YCBCR_LIMITED_RANGE] = {
+			/*
+			 * BT.601 limited range:
+			 *
+			 * |R|   |1.1644  0.0000  1.5960|   |Y  - 16 |
+			 * |G| = |1.1644 -0.3917 -0.8129| * |Cb - 128|
+			 * |B|   |1.1644  2.0172  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x12a) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x199) | CSC0_COEF1_B1(0x12a),
+			CSC0_COEF2_B2(0x79c) | CSC0_COEF2_B3(0x730),
+			CSC0_COEF3_C1(0x12a) | CSC0_COEF3_C2(0x204),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x1f0),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+		[DRM_COLOR_YCBCR_FULL_RANGE] = {
+			/*
+			 * BT.601 full range:
+			 *
+			 * |R|   |1.0000  0.0000  1.4020|   |Y  - 0  |
+			 * |G| = |1.0000 -0.3441 -0.7141| * |Cb - 128|
+			 * |B|   |1.0000  1.7720  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x100) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x167) | CSC0_COEF1_B1(0x100),
+			CSC0_COEF2_B2(0x7a8) | CSC0_COEF2_B3(0x749),
+			CSC0_COEF3_C1(0x100) | CSC0_COEF3_C2(0x1c6),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x000),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+	},
+	[DRM_COLOR_YCBCR_BT709] = {
+		[DRM_COLOR_YCBCR_LIMITED_RANGE] = {
+			/*
+			 * Rec.709 limited range:
+			 *
+			 * |R|   |1.1644  0.0000  1.7927|   |Y  - 16 |
+			 * |G| = |1.1644 -0.2132 -0.5329| * |Cb - 128|
+			 * |B|   |1.1644  2.1124  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x12a) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x1cb) | CSC0_COEF1_B1(0x12a),
+			CSC0_COEF2_B2(0x7c9) | CSC0_COEF2_B3(0x778),
+			CSC0_COEF3_C1(0x12a) | CSC0_COEF3_C2(0x21d),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x1f0),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+		[DRM_COLOR_YCBCR_FULL_RANGE] = {
+			/*
+			 * Rec.709 full range:
+			 *
+			 * |R|   |1.0000  0.0000  1.5748|   |Y  - 0  |
+			 * |G| = |1.0000 -0.1873 -0.4681| * |Cb - 128|
+			 * |B|   |1.0000  1.8556  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x100) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x193) | CSC0_COEF1_B1(0x100),
+			CSC0_COEF2_B2(0x7d0) | CSC0_COEF2_B3(0x788),
+			CSC0_COEF3_C1(0x100) | CSC0_COEF3_C2(0x1db),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x000),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+	},
+	[DRM_COLOR_YCBCR_BT2020] = {
+		[DRM_COLOR_YCBCR_LIMITED_RANGE] = {
+			/*
+			 * BT.2020 limited range:
+			 *
+			 * |R|   |1.1644  0.0000  1.6787|   |Y  - 16 |
+			 * |G| = |1.1644 -0.1874 -0.6505| * |Cb - 128|
+			 * |B|   |1.1644  2.1418  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x12a) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x1ae) | CSC0_COEF1_B1(0x12a),
+			CSC0_COEF2_B2(0x7d0) | CSC0_COEF2_B3(0x759),
+			CSC0_COEF3_C1(0x12a) | CSC0_COEF3_C2(0x224),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x1f0),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+		[DRM_COLOR_YCBCR_FULL_RANGE] = {
+			/*
+			 * BT.2020 full range:
+			 *
+			 * |R|   |1.0000  0.0000  1.4746|   |Y  - 0  |
+			 * |G| = |1.0000 -0.1646 -0.5714| * |Cb - 128|
+			 * |B|   |1.0000  1.8814  0.0000|   |Cr - 128|
+			 */
+			CSC0_COEF0_A1(0x100) | CSC0_COEF0_A2(0x000),
+			CSC0_COEF1_A3(0x179) | CSC0_COEF1_B1(0x100),
+			CSC0_COEF2_B2(0x7d6) | CSC0_COEF2_B3(0x76e),
+			CSC0_COEF3_C1(0x100) | CSC0_COEF3_C2(0x1e2),
+			CSC0_COEF4_C3(0x000) | CSC0_COEF4_D1(0x000),
+			CSC0_COEF5_D2(0x180) | CSC0_COEF5_D3(0x180),
+		},
+	},
+};
+
 static void lcdif_set_formats(struct lcdif_drm_private *lcdif,
+			      struct drm_plane_state *plane_state,
 			      const u32 bus_format)
 {
 	struct drm_device *drm = lcdif->drm;
-	const u32 format = lcdif->crtc.primary->state->fb->format->format;
-
-	writel(CSC0_CTRL_BYPASS, lcdif->base + LCDC_V8_CSC0_CTRL);
+	const u32 format = plane_state->fb->format->format;
+	bool in_yuv = false;
+	bool out_yuv = false;
 
 	switch (bus_format) {
 	case MEDIA_BUS_FMT_RGB565_1X16:
@@ -52,6 +159,78 @@  static void lcdif_set_formats(struct lcdif_drm_private *lcdif,
 	case MEDIA_BUS_FMT_UYVY8_1X16:
 		writel(DISP_PARA_LINE_PATTERN_UYVY_H,
 		       lcdif->base + LCDC_V8_DISP_PARA);
+		out_yuv = true;
+		break;
+	default:
+		dev_err(drm->dev, "Unknown media bus format 0x%x\n", bus_format);
+		break;
+	}
+
+	switch (format) {
+	/* RGB Formats */
+	case DRM_FORMAT_RGB565:
+		writel(CTRLDESCL0_5_BPP_16_RGB565,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+	case DRM_FORMAT_RGB888:
+		writel(CTRLDESCL0_5_BPP_24_RGB888,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+	case DRM_FORMAT_XRGB1555:
+		writel(CTRLDESCL0_5_BPP_16_ARGB1555,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+	case DRM_FORMAT_XRGB4444:
+		writel(CTRLDESCL0_5_BPP_16_ARGB4444,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+	case DRM_FORMAT_XBGR8888:
+		writel(CTRLDESCL0_5_BPP_32_ABGR8888,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+	case DRM_FORMAT_XRGB8888:
+		writel(CTRLDESCL0_5_BPP_32_ARGB8888,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		break;
+
+	/* YUYV Formats */
+	case DRM_FORMAT_YUYV:
+		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_VY2UY1,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		in_yuv = true;
+		break;
+	case DRM_FORMAT_YVYU:
+		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_UY2VY1,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		in_yuv = true;
+		break;
+	case DRM_FORMAT_UYVY:
+		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2VY1U,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		in_yuv = true;
+		break;
+	case DRM_FORMAT_VYUY:
+		writel(CTRLDESCL0_5_BPP_YCbCr422 | CTRLDESCL0_5_YUV_FORMAT_Y2UY1V,
+		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
+		in_yuv = true;
+		break;
+
+	default:
+		dev_err(drm->dev, "Unknown pixel format 0x%x\n", format);
+		break;
+	}
+
+	/*
+	 * The CSC differentiates between "YCbCr" and "YUV", but the reference
+	 * manual doesn't detail how they differ. Experiments showed that the
+	 * luminance value is unaffected, only the calculations involving chroma
+	 * values differ. The YCbCr mode behaves as expected, with chroma values
+	 * being offset by 128. The YUV mode isn't fully understood.
+	 */
+	if (!in_yuv && out_yuv) {
+		/* RGB -> YCbCr */
+		writel(CSC0_CTRL_CSC_MODE_RGB2YCbCr,
+		       lcdif->base + LCDC_V8_CSC0_CTRL);
 
 		/*
 		 * CSC: BT.601 Limited Range RGB to YCbCr coefficients.
@@ -72,44 +251,24 @@  static void lcdif_set_formats(struct lcdif_drm_private *lcdif,
 		       lcdif->base + LCDC_V8_CSC0_COEF4);
 		writel(CSC0_COEF5_D3(0x080) | CSC0_COEF5_D2(0x080),
 		       lcdif->base + LCDC_V8_CSC0_COEF5);
+	} else if (in_yuv && !out_yuv) {
+		/* YCbCr -> RGB */
+		const u32 *coeffs =
+			lcdif_yuv2rgb_coeffs[plane_state->color_encoding]
+					    [plane_state->color_range];
 
-		writel(CSC0_CTRL_CSC_MODE_RGB2YCbCr,
+		writel(CSC0_CTRL_CSC_MODE_YCbCr2RGB,
 		       lcdif->base + LCDC_V8_CSC0_CTRL);
 
-		break;
-	default:
-		dev_err(drm->dev, "Unknown media bus format 0x%x\n", bus_format);
-		break;
-	}
-
-	switch (format) {
-	case DRM_FORMAT_RGB565:
-		writel(CTRLDESCL0_5_BPP_16_RGB565,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	case DRM_FORMAT_RGB888:
-		writel(CTRLDESCL0_5_BPP_24_RGB888,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	case DRM_FORMAT_XRGB1555:
-		writel(CTRLDESCL0_5_BPP_16_ARGB1555,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	case DRM_FORMAT_XRGB4444:
-		writel(CTRLDESCL0_5_BPP_16_ARGB4444,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	case DRM_FORMAT_XBGR8888:
-		writel(CTRLDESCL0_5_BPP_32_ABGR8888,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	case DRM_FORMAT_XRGB8888:
-		writel(CTRLDESCL0_5_BPP_32_ARGB8888,
-		       lcdif->base + LCDC_V8_CTRLDESCL0_5);
-		break;
-	default:
-		dev_err(drm->dev, "Unknown pixel format 0x%x\n", format);
-		break;
+		writel(coeffs[0], lcdif->base + LCDC_V8_CSC0_COEF0);
+		writel(coeffs[1], lcdif->base + LCDC_V8_CSC0_COEF1);
+		writel(coeffs[2], lcdif->base + LCDC_V8_CSC0_COEF2);
+		writel(coeffs[3], lcdif->base + LCDC_V8_CSC0_COEF3);
+		writel(coeffs[4], lcdif->base + LCDC_V8_CSC0_COEF4);
+		writel(coeffs[5], lcdif->base + LCDC_V8_CSC0_COEF5);
+	} else {
+		/* RGB -> RGB, YCbCr -> YCbCr: bypass colorspace converter. */
+		writel(CSC0_CTRL_BYPASS, lcdif->base + LCDC_V8_CSC0_CTRL);
 	}
 }
 
@@ -207,6 +366,7 @@  static void lcdif_reset_block(struct lcdif_drm_private *lcdif)
 }
 
 static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
+				     struct drm_plane_state *plane_state,
 				     struct drm_bridge_state *bridge_state,
 				     const u32 bus_format)
 {
@@ -229,7 +389,7 @@  static void lcdif_crtc_mode_set_nofb(struct lcdif_drm_private *lcdif,
 	/* Mandatory eLCDIF reset as per the Reference Manual */
 	lcdif_reset_block(lcdif);
 
-	lcdif_set_formats(lcdif, bus_format);
+	lcdif_set_formats(lcdif, plane_state, bus_format);
 
 	lcdif_set_mode(lcdif, bus_flags);
 }
@@ -312,7 +472,7 @@  static void lcdif_crtc_atomic_enable(struct drm_crtc *crtc,
 
 	pm_runtime_get_sync(drm->dev);
 
-	lcdif_crtc_mode_set_nofb(lcdif, bridge_state, bus_format);
+	lcdif_crtc_mode_set_nofb(lcdif, new_pstate, bridge_state, bus_format);
 
 	/* Write cur_buf as well to avoid an initial corrupt frame */
 	paddr = drm_fb_cma_get_gem_addr(new_pstate->fb, new_pstate, 0);
@@ -456,12 +616,19 @@  static const struct drm_plane_funcs lcdif_plane_funcs = {
 };
 
 static const u32 lcdif_primary_plane_formats[] = {
+	/* RGB */
 	DRM_FORMAT_RGB565,
 	DRM_FORMAT_RGB888,
 	DRM_FORMAT_XBGR8888,
 	DRM_FORMAT_XRGB1555,
 	DRM_FORMAT_XRGB4444,
 	DRM_FORMAT_XRGB8888,
+
+	/* Packed YCbCr */
+	DRM_FORMAT_YUYV,
+	DRM_FORMAT_YVYU,
+	DRM_FORMAT_UYVY,
+	DRM_FORMAT_VYUY,
 };
 
 static const u64 lcdif_modifiers[] = {
@@ -475,6 +642,11 @@  static const u64 lcdif_modifiers[] = {
 
 int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 {
+	const u32 supported_encodings = BIT(DRM_COLOR_YCBCR_BT601) |
+					BIT(DRM_COLOR_YCBCR_BT709) |
+					BIT(DRM_COLOR_YCBCR_BT2020);
+	const u32 supported_ranges = BIT(DRM_COLOR_YCBCR_LIMITED_RANGE) |
+				     BIT(DRM_COLOR_YCBCR_FULL_RANGE);
 	struct drm_encoder *encoder = &lcdif->encoder;
 	struct drm_crtc *crtc = &lcdif->crtc;
 	int ret;
@@ -490,6 +662,14 @@  int lcdif_kms_init(struct lcdif_drm_private *lcdif)
 	if (ret)
 		return ret;
 
+	ret = drm_plane_create_color_properties(&lcdif->planes.primary,
+						supported_encodings,
+						supported_ranges,
+						DRM_COLOR_YCBCR_BT601,
+						DRM_COLOR_YCBCR_LIMITED_RANGE);
+	if (ret)
+		return ret;
+
 	drm_crtc_helper_add(crtc, &lcdif_crtc_helper_funcs);
 	ret = drm_crtc_init_with_planes(lcdif->drm, crtc,
 					&lcdif->planes.primary, NULL,
diff --git a/drivers/gpu/drm/mxsfb/lcdif_regs.h b/drivers/gpu/drm/mxsfb/lcdif_regs.h
index 0d5d9bedd94a..fb74eb5ccbf1 100644
--- a/drivers/gpu/drm/mxsfb/lcdif_regs.h
+++ b/drivers/gpu/drm/mxsfb/lcdif_regs.h
@@ -216,7 +216,10 @@ 
 #define CTRLDESCL0_5_YUV_FORMAT_UY2VY1	(0x3 << 14)
 #define CTRLDESCL0_5_YUV_FORMAT_MASK	GENMASK(15, 14)
 
-#define CSC0_CTRL_CSC_MODE_RGB2YCbCr	GENMASK(2, 1)
+#define CSC0_CTRL_CSC_MODE_YUV2RGB	(0x0 << 1)
+#define CSC0_CTRL_CSC_MODE_YCbCr2RGB	(0x1 << 1)
+#define CSC0_CTRL_CSC_MODE_RGB2YUV	(0x2 << 1)
+#define CSC0_CTRL_CSC_MODE_RGB2YCbCr	(0x3 << 1)
 #define CSC0_CTRL_CSC_MODE_MASK		GENMASK(2, 1)
 #define CSC0_CTRL_BYPASS		BIT(0)