diff mbox series

[v7,3/6] drm/i915/dp: Program VSC Header and DB for Pixel Encoding/Colorimetry Format

Message ID 20190510015353.15119-4-gwan-gyeong.mun@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915/dp: Support for DP YCbCr4:2:0 outputs | expand

Commit Message

Gwan-gyeong Mun May 10, 2019, 1:53 a.m. UTC
Function intel_pixel_encoding_setup_vsc handles vsc header and data block
setup for pixel encoding / colorimetry format.

Setup VSC header and data block in function intel_pixel_encoding_setup_vsc
for pixel encoding / colorimetry format as per dp 1.4a spec,
section 2.2.5.7.1, table 2-119: VSC SDP Header Bytes, section 2.2.5.7.5,
table 2-120:VSC SDP Payload for DB16 through DB18.

v2:
  Minor style fix. [Maarten]
  Refer to commit ids instead of patchwork. [Maarten]

v6: Rebase

v7:
  Rebase and addressed review comments from Ville.
  Use a structure initializer instead of memset().
  Fix non-standard comment format.
  Remove a referring to specific commit.
  Add a setting of dynamic range bit to  vsc_sdp.DB17.
  Add a setting of bpc which is based on pipe_bpp.
  Remove duplicated checking of connector's ycbcr_420_allowed from
  intel_pixel_encoding_setup_vsc(). It is already checked from
  intel_dp_ycbcr420_config().
  Remove comments for VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED. It is
  already implemented on intel_dp_get_colorimetry_status().

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
---
 drivers/gpu/drm/i915/intel_ddi.c |  1 +
 drivers/gpu/drm/i915/intel_dp.c  | 90 ++++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_drv.h |  2 +
 3 files changed, 93 insertions(+)

Comments

Maarten Lankhorst May 17, 2019, 1:36 p.m. UTC | #1
Op 10-05-2019 om 03:53 schreef Gwan-gyeong Mun:
> Function intel_pixel_encoding_setup_vsc handles vsc header and data block
> setup for pixel encoding / colorimetry format.
>
> Setup VSC header and data block in function intel_pixel_encoding_setup_vsc
> for pixel encoding / colorimetry format as per dp 1.4a spec,
> section 2.2.5.7.1, table 2-119: VSC SDP Header Bytes, section 2.2.5.7.5,
> table 2-120:VSC SDP Payload for DB16 through DB18.
>
> v2:
>   Minor style fix. [Maarten]
>   Refer to commit ids instead of patchwork. [Maarten]
>
> v6: Rebase
>
> v7:
>   Rebase and addressed review comments from Ville.
>   Use a structure initializer instead of memset().
>   Fix non-standard comment format.
>   Remove a referring to specific commit.
>   Add a setting of dynamic range bit to  vsc_sdp.DB17.
>   Add a setting of bpc which is based on pipe_bpp.
>   Remove duplicated checking of connector's ycbcr_420_allowed from
>   intel_pixel_encoding_setup_vsc(). It is already checked from
>   intel_dp_ycbcr420_config().
>   Remove comments for VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED. It is
>   already implemented on intel_dp_get_colorimetry_status().
>
> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_ddi.c |  1 +
>  drivers/gpu/drm/i915/intel_dp.c  | 90 ++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_drv.h |  2 +
>  3 files changed, 93 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> index cd5277d98b03..2f1688ea5a2c 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -3391,6 +3391,7 @@ static void intel_enable_ddi_dp(struct intel_encoder *encoder,
>  
>  	intel_edp_backlight_on(crtc_state, conn_state);
>  	intel_psr_enable(intel_dp, crtc_state);
> +	intel_dp_ycbcr_420_enable(intel_dp, crtc_state);
>  	intel_edp_drrs_enable(intel_dp, crtc_state);
>  
>  	if (crtc_state->has_audio)
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 9f219f8f0c71..a3fd279a5c52 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4407,6 +4407,96 @@ u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
>  	return 0;
>  }
>  
> +static void
> +intel_pixel_encoding_setup_vsc(struct intel_dp *intel_dp,
> +			       const struct intel_crtc_state *crtc_state)
> +{
> +	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
> +	struct dp_sdp vsc_sdp = {};
> +
> +	/* Prepare VSC Header for SU as per DP 1.4a spec, Table 2-119 */
> +	vsc_sdp.sdp_header.HB0 = 0;
> +	vsc_sdp.sdp_header.HB1 = 0x7;
> +
> +	/*
> +	 * VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/
> +	 * Colorimetry Format indication.
> +	 */
> +	vsc_sdp.sdp_header.HB2 = 0x5;
> +
> +	/*
> +	 * VSC SDP supporting 3D stereo, + PSR2, + Pixel Encoding/
> +	 * Colorimetry Format indication (HB2 = 05h).
> +	 */
> +	vsc_sdp.sdp_header.HB3 = 0x13;
> +
> +	/*
> +	 * YCbCr 420 = 3h DB16[7:4] ITU-R BT.601 = 0h, ITU-R BT.709 = 1h
> +	 * DB16[3:0] DP 1.4a spec, Table 2-120
> +	 */
> +	vsc_sdp.DB[16] = 0x3 << 4; /* 0x3 << 4 , YCbCr 420*/
> +	/* RGB->YCBCR color conversion uses the BT.709 color space. */
> +	vsc_sdp.DB[16] |= 0x1; /* 0x1, ITU-R BT.709 */
> +
> +	/*
> +	 * For pixel encoding formats YCbCr444, YCbCr422, YCbCr420, and Y Only,
> +	 * the following Component Bit Depth values are defined:
> +	 * 001b = 8bpc.
> +	 * 010b = 10bpc.
> +	 * 011b = 12bpc.
> +	 * 100b = 16bpc.
> +	 */
> +	switch (crtc_state->pipe_bpp) {
> +	case 24: /* 8bpc */
> +		vsc_sdp.DB[17] = 0x1;
> +		break;
> +	case 30: /* 10bpc */
> +		vsc_sdp.DB[17] = 0x2;
> +		break;
> +	case 36: /* 12bpc */
> +		vsc_sdp.DB[17] = 0x3;
> +		break;
> +	case 48: /* 16bpc */
> +		vsc_sdp.DB[17] = 0x4;
> +		break;
> +	default:
> +		DRM_DEBUG_KMS("Invalid bpp value '%d'\n", crtc_state->pipe_bpp);

I would use MISSING_CASE(crtc_state->pipe_bpp); here, as it's pretty fatal to VSC setup. :)

Otherwise series looks good from an atomic point of view. I would try to get an ACK from the analogix bridge maintainer for
inclusion in the drm-intel-next-queued tree, since it seems harmless enough to include from there.

So for whole series:
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

> +		break;
> +	}
> +
> +	/*
> +	 * Dynamic Range (Bit 7)
> +	 * 0 = VESA range, 1 = CTA range.
> +	 * all YCbCr are always limited range
> +	 */
> +	vsc_sdp.DB[17] |= 0x80;
> +
> +	/*
> +	 * Content Type (Bits 2:0)
> +	 * 000b = Not defined.
> +	 * 001b = Graphics.
> +	 * 010b = Photo.
> +	 * 011b = Video.
> +	 * 100b = Game
> +	 * All other values are RESERVED.
> +	 * Note: See CTA-861-G for the definition and expected
> +	 * processing by a stream sink for the above contect types.
> +	 */
> +	vsc_sdp.DB[18] = 0;
> +
> +	intel_dig_port->write_infoframe(&intel_dig_port->base,
> +			crtc_state, DP_SDP_VSC, &vsc_sdp, sizeof(vsc_sdp));
> +}
> +
> +void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
> +			       const struct intel_crtc_state *crtc_state)
> +{
> +	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_YCBCR420)
> +		return;
> +
> +	intel_pixel_encoding_setup_vsc(intel_dp, crtc_state);
> +}
> +
>  static u8 intel_dp_autotest_link_training(struct intel_dp *intel_dp)
>  {
>  	int status = 0;
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 247893ed1543..5d1845526cf8 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1576,6 +1576,8 @@ void intel_dp_get_m_n(struct intel_crtc *crtc,
>  		      struct intel_crtc_state *pipe_config);
>  void intel_dp_set_m_n(const struct intel_crtc_state *crtc_state,
>  		      enum link_m_n_set m_n);
> +void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
> +			       const struct intel_crtc_state *crtc_state);
>  int intel_dotclock_calculate(int link_freq, const struct intel_link_m_n *m_n);
>  bool bxt_find_best_dpll(struct intel_crtc_state *crtc_state,
>  			struct dpll *best_clock);
Gwan-gyeong Mun May 20, 2019, 8:23 a.m. UTC | #2
On Fri, 2019-05-17 at 15:36 +0200, Maarten Lankhorst wrote:
> Op 10-05-2019 om 03:53 schreef Gwan-gyeong Mun:
> > Function intel_pixel_encoding_setup_vsc handles vsc header and data
> > block
> > setup for pixel encoding / colorimetry format.
> > 
> > Setup VSC header and data block in function
> > intel_pixel_encoding_setup_vsc
> > for pixel encoding / colorimetry format as per dp 1.4a spec,
> > section 2.2.5.7.1, table 2-119: VSC SDP Header Bytes, section
> > 2.2.5.7.5,
> > table 2-120:VSC SDP Payload for DB16 through DB18.
> > 
> > v2:
> >   Minor style fix. [Maarten]
> >   Refer to commit ids instead of patchwork. [Maarten]
> > 
> > v6: Rebase
> > 
> > v7:
> >   Rebase and addressed review comments from Ville.
> >   Use a structure initializer instead of memset().
> >   Fix non-standard comment format.
> >   Remove a referring to specific commit.
> >   Add a setting of dynamic range bit to  vsc_sdp.DB17.
> >   Add a setting of bpc which is based on pipe_bpp.
> >   Remove duplicated checking of connector's ycbcr_420_allowed from
> >   intel_pixel_encoding_setup_vsc(). It is already checked from
> >   intel_dp_ycbcr420_config().
> >   Remove comments for VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED.
> > It is
> >   already implemented on intel_dp_get_colorimetry_status().
> > 
> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_ddi.c |  1 +
> >  drivers/gpu/drm/i915/intel_dp.c  | 90
> > ++++++++++++++++++++++++++++++++
> >  drivers/gpu/drm/i915/intel_drv.h |  2 +
> >  3 files changed, 93 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_ddi.c
> > b/drivers/gpu/drm/i915/intel_ddi.c
> > index cd5277d98b03..2f1688ea5a2c 100644
> > --- a/drivers/gpu/drm/i915/intel_ddi.c
> > +++ b/drivers/gpu/drm/i915/intel_ddi.c
> > @@ -3391,6 +3391,7 @@ static void intel_enable_ddi_dp(struct
> > intel_encoder *encoder,
> >  
> >  	intel_edp_backlight_on(crtc_state, conn_state);
> >  	intel_psr_enable(intel_dp, crtc_state);
> > +	intel_dp_ycbcr_420_enable(intel_dp, crtc_state);
> >  	intel_edp_drrs_enable(intel_dp, crtc_state);
> >  
> >  	if (crtc_state->has_audio)
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c
> > b/drivers/gpu/drm/i915/intel_dp.c
> > index 9f219f8f0c71..a3fd279a5c52 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4407,6 +4407,96 @@ u8 intel_dp_dsc_get_slice_count(struct
> > intel_dp *intel_dp,
> >  	return 0;
> >  }
> >  
> > +static void
> > +intel_pixel_encoding_setup_vsc(struct intel_dp *intel_dp,
> > +			       const struct intel_crtc_state
> > *crtc_state)
> > +{
> > +	struct intel_digital_port *intel_dig_port =
> > dp_to_dig_port(intel_dp);
> > +	struct dp_sdp vsc_sdp = {};
> > +
> > +	/* Prepare VSC Header for SU as per DP 1.4a spec, Table 2-119
> > */
> > +	vsc_sdp.sdp_header.HB0 = 0;
> > +	vsc_sdp.sdp_header.HB1 = 0x7;
> > +
> > +	/*
> > +	 * VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/
> > +	 * Colorimetry Format indication.
> > +	 */
> > +	vsc_sdp.sdp_header.HB2 = 0x5;
> > +
> > +	/*
> > +	 * VSC SDP supporting 3D stereo, + PSR2, + Pixel Encoding/
> > +	 * Colorimetry Format indication (HB2 = 05h).
> > +	 */
> > +	vsc_sdp.sdp_header.HB3 = 0x13;
> > +
> > +	/*
> > +	 * YCbCr 420 = 3h DB16[7:4] ITU-R BT.601 = 0h, ITU-R BT.709 =
> > 1h
> > +	 * DB16[3:0] DP 1.4a spec, Table 2-120
> > +	 */
> > +	vsc_sdp.DB[16] = 0x3 << 4; /* 0x3 << 4 , YCbCr 420*/
> > +	/* RGB->YCBCR color conversion uses the BT.709 color space. */
> > +	vsc_sdp.DB[16] |= 0x1; /* 0x1, ITU-R BT.709 */
> > +
> > +	/*
> > +	 * For pixel encoding formats YCbCr444, YCbCr422, YCbCr420, and
> > Y Only,
> > +	 * the following Component Bit Depth values are defined:
> > +	 * 001b = 8bpc.
> > +	 * 010b = 10bpc.
> > +	 * 011b = 12bpc.
> > +	 * 100b = 16bpc.
> > +	 */
> > +	switch (crtc_state->pipe_bpp) {
> > +	case 24: /* 8bpc */
> > +		vsc_sdp.DB[17] = 0x1;
> > +		break;
> > +	case 30: /* 10bpc */
> > +		vsc_sdp.DB[17] = 0x2;
> > +		break;
> > +	case 36: /* 12bpc */
> > +		vsc_sdp.DB[17] = 0x3;
> > +		break;
> > +	case 48: /* 16bpc */
> > +		vsc_sdp.DB[17] = 0x4;
> > +		break;
> > +	default:
> > +		DRM_DEBUG_KMS("Invalid bpp value '%d'\n", crtc_state-
> > >pipe_bpp);
> 
> I would use MISSING_CASE(crtc_state->pipe_bpp); here, as it's pretty
> fatal to VSC setup. :)
> 
> Otherwise series looks good from an atomic point of view. I would try
> to get an ACK from the analogix bridge maintainer for
> inclusion in the drm-intel-next-queued tree, since it seems harmless
> enough to include from there.
> 
Hi,
Thank you for reviewing the series.
And I'll replace DRM_DEBUG_KMS() to MISSING_CASE() on default switch-
case.

> So for whole series:
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> 
> > +		break;
> > +	}
> > +
> > +	/*
> > +	 * Dynamic Range (Bit 7)
> > +	 * 0 = VESA range, 1 = CTA range.
> > +	 * all YCbCr are always limited range
> > +	 */
> > +	vsc_sdp.DB[17] |= 0x80;
> > +
> > +	/*
> > +	 * Content Type (Bits 2:0)
> > +	 * 000b = Not defined.
> > +	 * 001b = Graphics.
> > +	 * 010b = Photo.
> > +	 * 011b = Video.
> > +	 * 100b = Game
> > +	 * All other values are RESERVED.
> > +	 * Note: See CTA-861-G for the definition and expected
> > +	 * processing by a stream sink for the above contect types.
> > +	 */
> > +	vsc_sdp.DB[18] = 0;
> > +
> > +	intel_dig_port->write_infoframe(&intel_dig_port->base,
> > +			crtc_state, DP_SDP_VSC, &vsc_sdp,
> > sizeof(vsc_sdp));
> > +}
> > +
> > +void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
> > +			       const struct intel_crtc_state
> > *crtc_state)
> > +{
> > +	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_YCBCR420)
> > +		return;
> > +
> > +	intel_pixel_encoding_setup_vsc(intel_dp, crtc_state);
> > +}
> > +
> >  static u8 intel_dp_autotest_link_training(struct intel_dp
> > *intel_dp)
> >  {
> >  	int status = 0;
> > diff --git a/drivers/gpu/drm/i915/intel_drv.h
> > b/drivers/gpu/drm/i915/intel_drv.h
> > index 247893ed1543..5d1845526cf8 100644
> > --- a/drivers/gpu/drm/i915/intel_drv.h
> > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > @@ -1576,6 +1576,8 @@ void intel_dp_get_m_n(struct intel_crtc
> > *crtc,
> >  		      struct intel_crtc_state *pipe_config);
> >  void intel_dp_set_m_n(const struct intel_crtc_state *crtc_state,
> >  		      enum link_m_n_set m_n);
> > +void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
> > +			       const struct intel_crtc_state
> > *crtc_state);
> >  int intel_dotclock_calculate(int link_freq, const struct
> > intel_link_m_n *m_n);
> >  bool bxt_find_best_dpll(struct intel_crtc_state *crtc_state,
> >  			struct dpll *best_clock);
> 
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index cd5277d98b03..2f1688ea5a2c 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -3391,6 +3391,7 @@  static void intel_enable_ddi_dp(struct intel_encoder *encoder,
 
 	intel_edp_backlight_on(crtc_state, conn_state);
 	intel_psr_enable(intel_dp, crtc_state);
+	intel_dp_ycbcr_420_enable(intel_dp, crtc_state);
 	intel_edp_drrs_enable(intel_dp, crtc_state);
 
 	if (crtc_state->has_audio)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 9f219f8f0c71..a3fd279a5c52 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4407,6 +4407,96 @@  u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
 	return 0;
 }
 
+static void
+intel_pixel_encoding_setup_vsc(struct intel_dp *intel_dp,
+			       const struct intel_crtc_state *crtc_state)
+{
+	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+	struct dp_sdp vsc_sdp = {};
+
+	/* Prepare VSC Header for SU as per DP 1.4a spec, Table 2-119 */
+	vsc_sdp.sdp_header.HB0 = 0;
+	vsc_sdp.sdp_header.HB1 = 0x7;
+
+	/*
+	 * VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/
+	 * Colorimetry Format indication.
+	 */
+	vsc_sdp.sdp_header.HB2 = 0x5;
+
+	/*
+	 * VSC SDP supporting 3D stereo, + PSR2, + Pixel Encoding/
+	 * Colorimetry Format indication (HB2 = 05h).
+	 */
+	vsc_sdp.sdp_header.HB3 = 0x13;
+
+	/*
+	 * YCbCr 420 = 3h DB16[7:4] ITU-R BT.601 = 0h, ITU-R BT.709 = 1h
+	 * DB16[3:0] DP 1.4a spec, Table 2-120
+	 */
+	vsc_sdp.DB[16] = 0x3 << 4; /* 0x3 << 4 , YCbCr 420*/
+	/* RGB->YCBCR color conversion uses the BT.709 color space. */
+	vsc_sdp.DB[16] |= 0x1; /* 0x1, ITU-R BT.709 */
+
+	/*
+	 * For pixel encoding formats YCbCr444, YCbCr422, YCbCr420, and Y Only,
+	 * the following Component Bit Depth values are defined:
+	 * 001b = 8bpc.
+	 * 010b = 10bpc.
+	 * 011b = 12bpc.
+	 * 100b = 16bpc.
+	 */
+	switch (crtc_state->pipe_bpp) {
+	case 24: /* 8bpc */
+		vsc_sdp.DB[17] = 0x1;
+		break;
+	case 30: /* 10bpc */
+		vsc_sdp.DB[17] = 0x2;
+		break;
+	case 36: /* 12bpc */
+		vsc_sdp.DB[17] = 0x3;
+		break;
+	case 48: /* 16bpc */
+		vsc_sdp.DB[17] = 0x4;
+		break;
+	default:
+		DRM_DEBUG_KMS("Invalid bpp value '%d'\n", crtc_state->pipe_bpp);
+		break;
+	}
+
+	/*
+	 * Dynamic Range (Bit 7)
+	 * 0 = VESA range, 1 = CTA range.
+	 * all YCbCr are always limited range
+	 */
+	vsc_sdp.DB[17] |= 0x80;
+
+	/*
+	 * Content Type (Bits 2:0)
+	 * 000b = Not defined.
+	 * 001b = Graphics.
+	 * 010b = Photo.
+	 * 011b = Video.
+	 * 100b = Game
+	 * All other values are RESERVED.
+	 * Note: See CTA-861-G for the definition and expected
+	 * processing by a stream sink for the above contect types.
+	 */
+	vsc_sdp.DB[18] = 0;
+
+	intel_dig_port->write_infoframe(&intel_dig_port->base,
+			crtc_state, DP_SDP_VSC, &vsc_sdp, sizeof(vsc_sdp));
+}
+
+void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
+			       const struct intel_crtc_state *crtc_state)
+{
+	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_YCBCR420)
+		return;
+
+	intel_pixel_encoding_setup_vsc(intel_dp, crtc_state);
+}
+
 static u8 intel_dp_autotest_link_training(struct intel_dp *intel_dp)
 {
 	int status = 0;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 247893ed1543..5d1845526cf8 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1576,6 +1576,8 @@  void intel_dp_get_m_n(struct intel_crtc *crtc,
 		      struct intel_crtc_state *pipe_config);
 void intel_dp_set_m_n(const struct intel_crtc_state *crtc_state,
 		      enum link_m_n_set m_n);
+void intel_dp_ycbcr_420_enable(struct intel_dp *intel_dp,
+			       const struct intel_crtc_state *crtc_state);
 int intel_dotclock_calculate(int link_freq, const struct intel_link_m_n *m_n);
 bool bxt_find_best_dpll(struct intel_crtc_state *crtc_state,
 			struct dpll *best_clock);