drm/i915/dp: Add Read/Write support for Adaptive Sync SDP

Add the necessary structures and functions to handle reading and
unpacking Adaptive Sync Secondary Data Packets. Also add support
to write and pack AS SDP.

--v2:
- Correct use of REG_BIT and REG_GENMASK. [Jani]
- Use as_sdp instead of async. [Jani]
- Remove unrelated comments and changes. [Jani]
- Correct code indent. [Jani]

--v3:
- Update definition names for AS SDP which are starting from
HSW, as these defines are applicable for ADLP+.(Ankit)

--v4:
- Remove as_sdp_mode from crtc_state.
- Drop metadata keyword.
- For consistency, update ADL_ prefix or post fix as required.

--v5:
- Check if AS_SDP bit is set in crtc_state->infoframes.enable. If not
  return.
- Check for HAS_AS_SDP() before setting VIDEO_DIP_ENABLE_AS_ADL mask.

--v6:
- Rename intel_read_dp_infoframe_as_sdp to intel_read_dp_as_sdp.

--v7:
- Add read back for length and vtotal correction.

--v8:
- Use as_sdp->target_rr & 0xFF.
- Shift by 8 instead of 32, and drop casting to u64.
-  Remove changes which are does not belong to this patch.
Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240322031157.3823909-5-mitulkumar.ajitkumar.golani@intel.com

drivers/gpu/drm/i915/display/intel_display_device.h

@@ -69,6 +69,7 @@ struct drm_printer;
 #define HAS_TRANSCODER(i915, trans)	((DISPLAY_RUNTIME_INFO(i915)->cpu_transcoder_mask & \
 					  BIT(trans)) != 0)
 #define HAS_VRR(i915)			(DISPLAY_VER(i915) >= 11)
+#define HAS_AS_SDP(i915)		(DISPLAY_VER(i915) >= 13)
 #define INTEL_NUM_PIPES(i915)		(hweight8(DISPLAY_RUNTIME_INFO(i915)->pipe_mask))
 #define I915_HAS_HOTPLUG(i915)		(DISPLAY_INFO(i915)->has_hotplug)
 #define OVERLAY_NEEDS_PHYSICAL(i915)	(DISPLAY_INFO(i915)->overlay_needs_physical)

drivers/gpu/drm/i915/display/intel_dp.c

@@ -4162,6 +4162,32 @@ intel_dp_needs_vsc_sdp(const struct intel_crtc_state *crtc_state,
 	return false;
 }
 
+static ssize_t intel_dp_as_sdp_pack(const struct drm_dp_as_sdp *as_sdp,
+				    struct dp_sdp *sdp, size_t size)
+{
+	size_t length = sizeof(struct dp_sdp);
+
+	if (size < length)
+		return -ENOSPC;
+
+	memset(sdp, 0, size);
+
+	/* Prepare AS (Adaptive Sync) SDP Header */
+	sdp->sdp_header.HB0 = 0;
+	sdp->sdp_header.HB1 = as_sdp->sdp_type;
+	sdp->sdp_header.HB2 = 0x02;
+	sdp->sdp_header.HB3 = as_sdp->length;
+
+	/* Fill AS (Adaptive Sync) SDP Payload */
+	sdp->db[0] = as_sdp->mode;
+	sdp->db[1] = as_sdp->vtotal & 0xFF;
+	sdp->db[2] = (as_sdp->vtotal >> 8) & 0xFF;
+	sdp->db[3] = as_sdp->target_rr & 0xFF;
+	sdp->db[4] = (as_sdp->target_rr >> 8) & 0x3;
+
+	return length;
+}
+
 static ssize_t
 intel_dp_hdr_metadata_infoframe_sdp_pack(struct drm_i915_private *i915,
 					 const struct hdmi_drm_infoframe *drm_infoframe,
@@ -4261,6 +4287,10 @@ static void intel_write_dp_sdp(struct intel_encoder *encoder,
 							       &crtc_state->infoframes.drm.drm,
 							       &sdp, sizeof(sdp));
 		break;
+	case DP_SDP_ADAPTIVE_SYNC:
+		len = intel_dp_as_sdp_pack(&crtc_state->infoframes.as_sdp, &sdp,
+					   sizeof(sdp));
+		break;
 	default:
 		MISSING_CASE(type);
 		return;
@@ -4282,6 +4312,10 @@ void intel_dp_set_infoframes(struct intel_encoder *encoder,
 	u32 dip_enable = VIDEO_DIP_ENABLE_AVI_HSW | VIDEO_DIP_ENABLE_GCP_HSW |
 			 VIDEO_DIP_ENABLE_VS_HSW | VIDEO_DIP_ENABLE_GMP_HSW |
 			 VIDEO_DIP_ENABLE_SPD_HSW | VIDEO_DIP_ENABLE_DRM_GLK;
+
+	if (HAS_AS_SDP(dev_priv))
+		dip_enable |= VIDEO_DIP_ENABLE_AS_ADL;
+
 	u32 val = intel_de_read(dev_priv, reg) & ~dip_enable;
 
 	/* TODO: Sanitize DSC enabling wrt. intel_dsc_dp_pps_write(). */
@@ -4303,6 +4337,37 @@ void intel_dp_set_infoframes(struct intel_encoder *encoder,
 	intel_write_dp_sdp(encoder, crtc_state, HDMI_PACKET_TYPE_GAMUT_METADATA);
 }
 
+static
+int intel_dp_as_sdp_unpack(struct drm_dp_as_sdp *as_sdp,
+			   const void *buffer, size_t size)
+{
+	const struct dp_sdp *sdp = buffer;
+
+	if (size < sizeof(struct dp_sdp))
+		return -EINVAL;
+
+	memset(as_sdp, 0, sizeof(*as_sdp));
+
+	if (sdp->sdp_header.HB0 != 0)
+		return -EINVAL;
+
+	if (sdp->sdp_header.HB1 != DP_SDP_ADAPTIVE_SYNC)
+		return -EINVAL;
+
+	if (sdp->sdp_header.HB2 != 0x02)
+		return -EINVAL;
+
+	if ((sdp->sdp_header.HB3 & 0x3F) != 9)
+		return -EINVAL;
+
+	as_sdp->length = sdp->sdp_header.HB3 & DP_ADAPTIVE_SYNC_SDP_LENGTH;
+	as_sdp->mode = sdp->db[0] & DP_ADAPTIVE_SYNC_SDP_OPERATION_MODE;
+	as_sdp->vtotal = (sdp->db[2] << 8) | sdp->db[1];
+	as_sdp->target_rr = (u64)sdp->db[3] | ((u64)sdp->db[4] & 0x3);
+
+	return 0;
+}
+
 static int intel_dp_vsc_sdp_unpack(struct drm_dp_vsc_sdp *vsc,
 				   const void *buffer, size_t size)
 {
@@ -4373,6 +4438,29 @@ static int intel_dp_vsc_sdp_unpack(struct drm_dp_vsc_sdp *vsc,
 	return 0;
 }
 
+static void
+intel_read_dp_as_sdp(struct intel_encoder *encoder,
+		     struct intel_crtc_state *crtc_state,
+		     struct drm_dp_as_sdp *as_sdp)
+{
+	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
+	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
+	unsigned int type = DP_SDP_ADAPTIVE_SYNC;
+	struct dp_sdp sdp = {};
+	int ret;
+
+	if ((crtc_state->infoframes.enable &
+	     intel_hdmi_infoframe_enable(type)) == 0)
+		return;
+
+	dig_port->read_infoframe(encoder, crtc_state, type, &sdp,
+				 sizeof(sdp));
+
+	ret = intel_dp_as_sdp_unpack(as_sdp, &sdp, sizeof(sdp));
+	if (ret)
+		drm_dbg_kms(&dev_priv->drm, "Failed to unpack DP AS SDP\n");
+}
+
 static int
 intel_dp_hdr_metadata_infoframe_sdp_unpack(struct hdmi_drm_infoframe *drm_infoframe,
 					   const void *buffer, size_t size)
@@ -4479,6 +4567,10 @@ void intel_read_dp_sdp(struct intel_encoder *encoder,
 		intel_read_dp_hdr_metadata_infoframe_sdp(encoder, crtc_state,
 							 &crtc_state->infoframes.drm.drm);
 		break;
+	case DP_SDP_ADAPTIVE_SYNC:
+		intel_read_dp_as_sdp(encoder, crtc_state,
+				     &crtc_state->infoframes.as_sdp);
+		break;
 	default:
 		MISSING_CASE(type);
 		break;

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -114,6 +114,8 @@ static u32 g4x_infoframe_enable(unsigned int type)
 		return VIDEO_DIP_ENABLE_GAMUT;
 	case DP_SDP_VSC:
 		return 0;
+	case DP_SDP_ADAPTIVE_SYNC:
+		return 0;
 	case HDMI_INFOFRAME_TYPE_AVI:
 		return VIDEO_DIP_ENABLE_AVI;
 	case HDMI_INFOFRAME_TYPE_SPD:
@@ -137,6 +139,8 @@ static u32 hsw_infoframe_enable(unsigned int type)
 		return VIDEO_DIP_ENABLE_GMP_HSW;
 	case DP_SDP_VSC:
 		return VIDEO_DIP_ENABLE_VSC_HSW;
+	case DP_SDP_ADAPTIVE_SYNC:
+		return VIDEO_DIP_ENABLE_AS_ADL;
 	case DP_SDP_PPS:
 		return VDIP_ENABLE_PPS;
 	case HDMI_INFOFRAME_TYPE_AVI:
@@ -164,6 +168,8 @@ hsw_dip_data_reg(struct drm_i915_private *dev_priv,
 		return HSW_TVIDEO_DIP_GMP_DATA(cpu_transcoder, i);
 	case DP_SDP_VSC:
 		return HSW_TVIDEO_DIP_VSC_DATA(cpu_transcoder, i);
+	case DP_SDP_ADAPTIVE_SYNC:
+		return ADL_TVIDEO_DIP_AS_SDP_DATA(cpu_transcoder, i);
 	case DP_SDP_PPS:
 		return ICL_VIDEO_DIP_PPS_DATA(cpu_transcoder, i);
 	case HDMI_INFOFRAME_TYPE_AVI:
@@ -186,6 +192,8 @@ static int hsw_dip_data_size(struct drm_i915_private *dev_priv,
 	switch (type) {
 	case DP_SDP_VSC:
 		return VIDEO_DIP_VSC_DATA_SIZE;
+	case DP_SDP_ADAPTIVE_SYNC:
+		return VIDEO_DIP_ASYNC_DATA_SIZE;
 	case DP_SDP_PPS:
 		return VIDEO_DIP_PPS_DATA_SIZE;
 	case HDMI_PACKET_TYPE_GAMUT_METADATA:
@@ -563,6 +571,9 @@ static u32 hsw_infoframes_enabled(struct intel_encoder *encoder,
 	if (DISPLAY_VER(dev_priv) >= 10)
 		mask |= VIDEO_DIP_ENABLE_DRM_GLK;
 
+	if (HAS_AS_SDP(dev_priv))
+		mask |= VIDEO_DIP_ENABLE_AS_ADL;
+
 	return val & mask;
 }
 
@@ -570,6 +581,7 @@ static const u8 infoframe_type_to_idx[] = {
 	HDMI_PACKET_TYPE_GENERAL_CONTROL,
 	HDMI_PACKET_TYPE_GAMUT_METADATA,
 	DP_SDP_VSC,
+	DP_SDP_ADAPTIVE_SYNC,
 	HDMI_INFOFRAME_TYPE_AVI,
 	HDMI_INFOFRAME_TYPE_SPD,
 	HDMI_INFOFRAME_TYPE_VENDOR,
@@ -1212,7 +1224,7 @@ static void hsw_set_infoframes(struct intel_encoder *encoder,
 	val &= ~(VIDEO_DIP_ENABLE_VSC_HSW | VIDEO_DIP_ENABLE_AVI_HSW |
 		 VIDEO_DIP_ENABLE_GCP_HSW | VIDEO_DIP_ENABLE_VS_HSW |
 		 VIDEO_DIP_ENABLE_GMP_HSW | VIDEO_DIP_ENABLE_SPD_HSW |
-		 VIDEO_DIP_ENABLE_DRM_GLK);
+		 VIDEO_DIP_ENABLE_DRM_GLK | VIDEO_DIP_ENABLE_AS_ADL);
 
 	if (!enable) {
 		intel_de_write(dev_priv, reg, val);

drivers/gpu/drm/i915/i915_reg.h

@@ -2310,6 +2310,7 @@
  * (Haswell and newer) to see which VIDEO_DIP_DATA byte corresponds to each byte
  * of the infoframe structure specified by CEA-861. */
 #define   VIDEO_DIP_DATA_SIZE	32
+#define   VIDEO_DIP_ASYNC_DATA_SIZE	36
 #define   VIDEO_DIP_GMP_DATA_SIZE	36
 #define   VIDEO_DIP_VSC_DATA_SIZE	36
 #define   VIDEO_DIP_PPS_DATA_SIZE	132
@@ -2348,6 +2349,8 @@
 #define   VIDEO_DIP_ENABLE_VS_HSW	(1 << 8)
 #define   VIDEO_DIP_ENABLE_GMP_HSW	(1 << 4)
 #define   VIDEO_DIP_ENABLE_SPD_HSW	(1 << 0)
+/* ADL and later: */
+#define   VIDEO_DIP_ENABLE_AS_ADL	REG_BIT(23)
 
 /* Panel fitting */
 #define PFIT_CONTROL	_MMIO(DISPLAY_MMIO_BASE(dev_priv) + 0x61230)
@@ -5039,6 +5042,7 @@
 #define _HSW_VIDEO_DIP_SPD_DATA_A	0x602A0
 #define _HSW_VIDEO_DIP_GMP_DATA_A	0x602E0
 #define _HSW_VIDEO_DIP_VSC_DATA_A	0x60320
+#define	_ADL_VIDEO_DIP_AS_DATA_A	0x60484
 #define _GLK_VIDEO_DIP_DRM_DATA_A	0x60440
 #define _HSW_VIDEO_DIP_AVI_ECC_A	0x60240
 #define _HSW_VIDEO_DIP_VS_ECC_A		0x60280
@@ -5053,6 +5057,7 @@
 #define _HSW_VIDEO_DIP_SPD_DATA_B	0x612A0
 #define _HSW_VIDEO_DIP_GMP_DATA_B	0x612E0
 #define _HSW_VIDEO_DIP_VSC_DATA_B	0x61320
+#define _ADL_VIDEO_DIP_AS_DATA_B	0x61484
 #define _GLK_VIDEO_DIP_DRM_DATA_B	0x61440
 #define _HSW_VIDEO_DIP_BVI_ECC_B	0x61240
 #define _HSW_VIDEO_DIP_VS_ECC_B		0x61280
@@ -5082,6 +5087,9 @@
 #define GLK_TVIDEO_DIP_DRM_DATA(trans, i)	_MMIO_TRANS2(trans, _GLK_VIDEO_DIP_DRM_DATA_A + (i) * 4)
 #define ICL_VIDEO_DIP_PPS_DATA(trans, i)	_MMIO_TRANS2(trans, _ICL_VIDEO_DIP_PPS_DATA_A + (i) * 4)
 #define ICL_VIDEO_DIP_PPS_ECC(trans, i)		_MMIO_TRANS2(trans, _ICL_VIDEO_DIP_PPS_ECC_A + (i) * 4)
+/*ADLP and later: */
+#define ADL_TVIDEO_DIP_AS_SDP_DATA(trans, i)	_MMIO_TRANS2(trans,\
+							     _ADL_VIDEO_DIP_AS_DATA_A + (i) * 4)
 
 #define _HSW_STEREO_3D_CTL_A		0x70020
 #define   S3D_ENABLE			(1 << 31)