[PATCH 02/11] drm/amd/display: Query DPIA HPD status.

[Qingqing Zhuo]

From: Jimmy Kizito <Jimmy.Kizito at amd.com>

[Why]
Driver needs up to date DPIA HPD status.

[How]
Use HPD query command to get DPIA HPD status.

Reviewed-by: Meenakshikumar Somasundaram <Meenakshikumar.Somasundaram at amd.com>
Reviewed-by: Jun Lei <Jun.Lei at amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo at amd.com>
Signed-off-by: Jimmy Kizito <Jimmy.Kizito at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c |  3 ++-
 .../drm/amd/display/dc/core/dc_link_dpia.c    | 19 +++++++++++++++++++
 .../gpu/drm/amd/display/dc/inc/dc_link_dpia.h |  5 +++++
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 67ef357e5798..b40abd2bf7f6 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -33,6 +33,7 @@
 #include "gpio_service_interface.h"
 #include "core_status.h"
 #include "dc_link_dp.h"
+#include "dc_link_dpia.h"
 #include "dc_link_ddc.h"
 #include "link_hwss.h"
 #include "opp.h"
@@ -240,7 +241,7 @@ bool dc_link_detect_sink(struct dc_link *link, enum dc_connection_type *type)
 
 	/* Link may not have physical HPD pin. */
 	if (link->ep_type != DISPLAY_ENDPOINT_PHY) {
-		if (link->is_hpd_pending || !link->hpd_status)
+		if (link->is_hpd_pending || !dc_link_dpia_query_hpd_status(link))
 			*type = dc_connection_none;
 		else
 			*type = dc_connection_single;
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dpia.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dpia.c
index a5765f36d86f..1b7a8774b0c9 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dpia.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dpia.c
@@ -34,6 +34,7 @@
 #include "dm_helpers.h"
 #include "dmub/inc/dmub_cmd.h"
 #include "inc/link_dpcd.h"
+#include "dc_dmub_srv.h"
 
 #define DC_LOGGER \
 	link->ctx->logger
@@ -69,6 +70,24 @@ enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link)
 	return status;
 }
 
+bool dc_link_dpia_query_hpd_status(struct dc_link *link)
+{
+	union dmub_rb_cmd cmd = {0};
+	struct dc_dmub_srv *dmub_srv = link->ctx->dmub_srv;
+	bool is_hpd_high = false;
+
+	/* prepare QUERY_HPD command */
+	cmd.query_hpd.header.type = DMUB_CMD__QUERY_HPD_STATE;
+	cmd.query_hpd.data.instance = link->link_id.enum_id - ENUM_ID_1;
+	cmd.query_hpd.data.ch_type = AUX_CHANNEL_DPIA;
+
+	/* Return HPD status reported by DMUB if query successfully executed. */
+	if (dc_dmub_srv_cmd_with_reply_data(dmub_srv, &cmd) && cmd.query_hpd.data.status == AUX_RET_SUCCESS)
+		is_hpd_high = cmd.query_hpd.data.result;
+
+	return is_hpd_high;
+}
+
 /* Configure link as prescribed in link_setting; set LTTPR mode; and
  * Initialize link training settings.
  * Abort link training if sink unplug detected.
diff --git a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dpia.h b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dpia.h
index 74dafd0f9d3d..39c1d1d07357 100644
--- a/drivers/gpu/drm/amd/display/dc/inc/dc_link_dpia.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/dc_link_dpia.h
@@ -87,6 +87,11 @@ union dpia_set_config_data {
  */
 enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link);
 
+/* Query hot plug status of USB4 DP tunnel.
+ * Returns true if HPD high.
+ */
+bool dc_link_dpia_query_hpd_status(struct dc_link *link);
+
 /* Train DP tunneling link for USB4 DPIA display endpoint.
  * DPIA equivalent of dc_link_dp_perfrorm_link_training.
  * Aborts link training upon detection of sink unplug.
-- 
2.25.1