drm/amd/display: program PSR2 DPCD Configuration

[Why]
To support PSR2 Source DPCD configuration

[How]
Update the PSR2 Source DPCD settings while the PSR2 enabled
Signed-off-by: David Zhang <dingchen.zhang@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_link.c

@@ -3206,6 +3206,7 @@ bool dc_link_setup_psr(struct dc_link *link,
 	unsigned int panel_inst;
 	/* updateSinkPsrDpcdConfig*/
 	union dpcd_psr_configuration psr_configuration;
+	union dpcd_alpm_configuration alpm_configuration;
 
 	psr_context->controllerId = CONTROLLER_ID_UNDEFINED;
 
@@ -3231,7 +3232,7 @@ bool dc_link_setup_psr(struct dc_link *link,
 			psr_config->psr_frame_capture_indication_req;
 
 	/* Check for PSR v2*/
-	if (psr_config->psr_version == 0x2) {
+	if (link->psr_settings.psr_version == DC_PSR_VERSION_SU_1) {
 		/* For PSR v2 selective update.
 		 * Indicates whether sink should start capturing
 		 * immediately following active scan line,
@@ -3242,6 +3243,14 @@ bool dc_link_setup_psr(struct dc_link *link,
 		 * IRQ_HPD when CRC mismatch is detected.
 		 */
 		psr_configuration.bits.IRQ_HPD_WITH_CRC_ERROR    = 1;
+		/* For PSR v2, set the bit when the Source device will
+		 * be enabling PSR2 operation.
+		 */
+		psr_configuration.bits.ENABLE_PSR2    = 1;
+		/* For PSR v2, the Sink device must be able to receive
+		 * SU region updates early in the frame time.
+		 */
+		psr_configuration.bits.EARLY_TRANSPORT_ENABLE    = 1;
 	}
 
 	dm_helpers_dp_write_dpcd(
@@ -3251,6 +3260,18 @@ bool dc_link_setup_psr(struct dc_link *link,
 		&psr_configuration.raw,
 		sizeof(psr_configuration.raw));
 
+	if (link->psr_settings.psr_version == DC_PSR_VERSION_SU_1) {
+		memset(&alpm_configuration, 0, sizeof(alpm_configuration));
+
+		alpm_configuration.bits.ENABLE = 1;
+		dm_helpers_dp_write_dpcd(
+			link->ctx,
+			link,
+			DP_RECEIVER_ALPM_CONFIG,
+			&alpm_configuration.raw,
+			sizeof(alpm_configuration.raw));
+	}
+
 	psr_context->channel = link->ddc->ddc_pin->hw_info.ddc_channel;
 	psr_context->transmitterId = link->link_enc->transmitter;
 	psr_context->engineId = link->link_enc->preferred_engine;

drivers/gpu/drm/amd/display/dc/inc/hw/link_encoder.h

@@ -85,7 +85,18 @@ union dpcd_psr_configuration {
 		unsigned char LINE_CAPTURE_INDICATION   : 1;
 		/* For eDP 1.4, PSR v2*/
 		unsigned char IRQ_HPD_WITH_CRC_ERROR    : 1;
-		unsigned char RESERVED                  : 2;
+		unsigned char ENABLE_PSR2               : 1;
+		/* For eDP 1.5, PSR v2 w/ early transport */
+		unsigned char EARLY_TRANSPORT_ENABLE    : 1;
+	} bits;
+	unsigned char raw;
+};
+
+union dpcd_alpm_configuration {
+	struct {
+		unsigned char ENABLE                    : 1;
+		unsigned char IRQ_HPD_ENABLE            : 1;
+		unsigned char RESERVED                  : 6;
 	} bits;
 	unsigned char raw;
 };