[PATCH v2 2/6] drm/i915/dp: Add support of BT.2020 Colorimetry to DP MSA

[Shankar, Uma]

>-----Original Message-----
>From: Mun, Gwan-gyeong
>Sent: Friday, August 23, 2019 3:22 PM
>To: intel-gfx at lists.freedesktop.org
>Cc: dri-devel at lists.freedesktop.org; Shankar, Uma <uma.shankar at intel.com>;
>Sharma, Shashank <shashank.sharma at intel.com>
>Subject: [PATCH v2 2/6] drm/i915/dp: Add support of BT.2020 Colorimetry to DP MSA
>
>When BT.2020 Colorimetry output is used for DP, we should program BT.2020
>Colorimetry to MSA and VSC SDP. It adds output_colorspace to intel_crtc_state struct
>as a place holder of pipe's output colorspace.
>In order to distinguish needed colorimetry for VSC SDP, it adds
>intel_dp_needs_vsc_colorimetry function.
>If the output colorspace requires vsc sdp or output format is YCbCr 4:2:0, it uses MSA
>with VSC SDP.
>
>As per DP 1.4a spec section 2.2.4.3 [MSA Field for Indication of Color Encoding
>Format and Content Color Gamut] while sending
>BT.2020 Colorimetry signals we should program MSA MISC1 fields which indicate VSC
>SDP for the Pixel Encoding/Colorimetry Format.
>
>v2: Remove useless parentheses

The changes look good to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

>Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
>---
> drivers/gpu/drm/i915/display/intel_ddi.c      |  8 +++---
> .../drm/i915/display/intel_display_types.h    |  3 +++
> drivers/gpu/drm/i915/display/intel_dp.c       | 25 ++++++++++++++++++-
> drivers/gpu/drm/i915/display/intel_dp.h       |  1 +
> 4 files changed, 33 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c
>b/drivers/gpu/drm/i915/display/intel_ddi.c
>index 4f7ea0a35976..5c42b58c1c2f 100644
>--- a/drivers/gpu/drm/i915/display/intel_ddi.c
>+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
>@@ -1737,11 +1737,13 @@ void intel_ddi_set_pipe_settings(const struct
>intel_crtc_state *crtc_state)
> 	/*
> 	 * As per DP 1.4a spec section 2.2.4.3 [MSA Field for Indication
> 	 * of Color Encoding Format and Content Color Gamut] while sending
>-	 * YCBCR 420 signals we should program MSA MISC1 fields which
>-	 * indicate VSC SDP for the Pixel Encoding/Colorimetry Format.
>+	 * YCBCR 420, HDR BT.2020 signals we should program MSA MISC1 fields
>+	 * which indicate VSC SDP for the Pixel Encoding/Colorimetry Format.
> 	 */
>-	if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420)
>+	if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 ||
>+	    intel_dp_needs_vsc_colorimetry(crtc_state->output_colorspace))
> 		temp |= TRANS_MSA_USE_VSC_SDP;
>+
> 	I915_WRITE(TRANS_MSA_MISC(cpu_transcoder), temp);  }
>
>diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
>b/drivers/gpu/drm/i915/display/intel_display_types.h
>index 449abaea619f..9845abcf6f29 100644
>--- a/drivers/gpu/drm/i915/display/intel_display_types.h
>+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
>@@ -964,6 +964,9 @@ struct intel_crtc_state {
> 	/* Output format RGB/YCBCR etc */
> 	enum intel_output_format output_format;
>
>+	/* Output colorspace sRGB/BT.2020 etc */
>+	u32 output_colorspace;
>+
> 	/* Output down scaling is done in LSPCON device */
> 	bool lspcon_downsampling;
>
>diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
>b/drivers/gpu/drm/i915/display/intel_dp.c
>index 55d5ab97061c..295d5ed2be96 100644
>--- a/drivers/gpu/drm/i915/display/intel_dp.c
>+++ b/drivers/gpu/drm/i915/display/intel_dp.c
>@@ -2164,6 +2164,8 @@ intel_dp_compute_config(struct intel_encoder *encoder,
> 		pipe_config->has_pch_encoder = true;
>
> 	pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;
>+	pipe_config->output_colorspace = intel_conn_state->base.colorspace;
>+
> 	if (lspcon->active)
> 		lspcon_ycbcr420_config(&intel_connector->base, pipe_config);
> 	else
>@@ -4408,6 +4410,26 @@ u8 intel_dp_dsc_get_slice_count(struct intel_dp
>*intel_dp,
> 	return 0;
> }
>
>+bool
>+intel_dp_needs_vsc_colorimetry(u32 colorspace) {
>+	bool ret = false;
>+
>+	switch (colorspace) {
>+	case DRM_MODE_COLORIMETRY_SYCC_601:
>+	case DRM_MODE_COLORIMETRY_OPYCC_601:
>+	case DRM_MODE_COLORIMETRY_BT2020_YCC:
>+	case DRM_MODE_COLORIMETRY_BT2020_RGB:
>+	case DRM_MODE_COLORIMETRY_BT2020_CYCC:
>+		ret = true;
>+		break;
>+	default:
>+		break;
>+	}
>+
>+	return ret;
>+}
>+
> static void
> intel_dp_setup_vsc_sdp(struct intel_dp *intel_dp,
> 		       const struct intel_crtc_state *crtc_state, @@ -4536,7 +4558,8
>@@ void intel_dp_vsc_enable(struct intel_dp *intel_dp,
> 			 const struct intel_crtc_state *crtc_state,
> 			 const struct drm_connector_state *conn_state)  {
>-	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_YCBCR420)
>+	if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_YCBCR420 &&
>+	    !intel_dp_needs_vsc_colorimetry(conn_state->colorspace))
> 		return;
>
> 	intel_dp_setup_vsc_sdp(intel_dp, crtc_state, conn_state); diff --git
>a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
>index 91a0ee6058fe..b2da7c9998f7 100644
>--- a/drivers/gpu/drm/i915/display/intel_dp.h
>+++ b/drivers/gpu/drm/i915/display/intel_dp.h
>@@ -111,6 +111,7 @@ bool intel_dp_read_dpcd(struct intel_dp *intel_dp);  bool
>intel_dp_get_colorimetry_status(struct intel_dp *intel_dp);  int
>intel_dp_link_required(int pixel_clock, int bpp);  int intel_dp_max_data_rate(int
>max_link_clock, int max_lanes);
>+bool intel_dp_needs_vsc_colorimetry(u32 colorspace);
> void intel_dp_vsc_enable(struct intel_dp *intel_dp,
> 			 const struct intel_crtc_state *crtc_state,
> 			 const struct drm_connector_state *conn_state);
>--
>2.22.0