drm: apple: dptx: Port APCALL to macOS 13.3 firmware

The 13.3 firmware has an additional get_max_lane_count call inserted
with ID 10.

Signed-off-by: Janne Grunau <j@jannau.net>

Author: jannau

drivers/gpu/drm/apple/dptxep.c

@@ -28,6 +28,13 @@ struct dptxport_apcall_link_rate {
 	u8 _unk1[12];
 } __attribute__((packed));
 
+struct dptxport_apcall_lane_count {
+	__le32 retcode;
+	u8 _unk0[12];
+	__le64 lane_count;
+	u8 _unk1[8];
+} __attribute__((packed));
+
 struct dptxport_apcall_get_support {
 	__le32 retcode;
 	u8 _unk0[12];
@@ -157,6 +164,20 @@ static int dptxport_call_get_max_link_rate(struct apple_epic_service *service,
 	return 0;
 }
 
+static int dptxport_call_get_max_lane_count(struct apple_epic_service *service,
+					   void *reply_, size_t reply_size)
+{
+	struct dptxport_apcall_lane_count *reply = reply_;
+
+	if (reply_size < sizeof(*reply))
+		return -EINVAL;
+
+	reply->retcode = cpu_to_le32(0);
+	reply->lane_count = cpu_to_le64(4);
+
+	return 0;
+}
+
 static int dptxport_call_get_link_rate(struct apple_epic_service *service,
 				       void *reply_, size_t reply_size)
 {
@@ -310,6 +331,8 @@ static int dptxport_call(struct apple_epic_service *service, u32 idx,
 	case DPTX_APCALL_SET_LINK_RATE:
 		return dptxport_call_set_link_rate(service, data, data_size,
 						   reply, reply_size);
+	case DPTX_APCALL_GET_MAX_LANE_COUNT:
+		return dptxport_call_get_max_lane_count(service, reply, reply_size);
 	case DPTX_APCALL_GET_SUPPORTS_HPD:
 		return dptxport_call_get_supports_hpd(service, reply,
 						      reply_size);

drivers/gpu/drm/apple/dptxep.h

@@ -15,20 +15,21 @@ enum dptx_apcall {
 	DPTX_APCALL_GET_MAX_LINK_RATE = 7,
 	DPTX_APCALL_GET_LINK_RATE = 8,
 	DPTX_APCALL_SET_LINK_RATE = 9,
-	DPTX_APCALL_GET_ACTIVE_LANE_COUNT = 10,
-	DPTX_APCALL_SET_ACTIVE_LANE_COUNT = 11,
-	DPTX_APCALL_GET_SUPPORTS_DOWN_SPREAD = 12,
-	DPTX_APCALL_GET_DOWN_SPREAD = 13,
-	DPTX_APCALL_SET_DOWN_SPREAD = 14,
-	DPTX_APCALL_GET_SUPPORTS_LANE_MAPPING = 15,
-	DPTX_APCALL_SET_LANE_MAP = 16,
-	DPTX_APCALL_GET_SUPPORTS_HPD = 17,
-	DPTX_APCALL_FORCE_HOTPLUG_DETECT = 18,
-	DPTX_APCALL_INACTIVE_SINK_DETECTED = 19,
-	DPTX_APCALL_SET_TILED_DISPLAY_HINTS = 20,
-	DPTX_APCALL_DEVICE_NOT_RESPONDING = 21,
-	DPTX_APCALL_DEVICE_BUSY_TIMEOUT = 22,
-	DPTX_APCALL_DEVICE_NOT_STARTED = 23,
+	DPTX_APCALL_GET_MAX_LANE_COUNT = 10,
+	DPTX_APCALL_GET_ACTIVE_LANE_COUNT = 11,
+	DPTX_APCALL_SET_ACTIVE_LANE_COUNT = 12,
+	DPTX_APCALL_GET_SUPPORTS_DOWN_SPREAD = 13,
+	DPTX_APCALL_GET_DOWN_SPREAD = 14,
+	DPTX_APCALL_SET_DOWN_SPREAD = 15,
+	DPTX_APCALL_GET_SUPPORTS_LANE_MAPPING = 16,
+	DPTX_APCALL_SET_LANE_MAP = 17,
+	DPTX_APCALL_GET_SUPPORTS_HPD = 18,
+	DPTX_APCALL_FORCE_HOTPLUG_DETECT = 19,
+	DPTX_APCALL_INACTIVE_SINK_DETECTED = 20,
+	DPTX_APCALL_SET_TILED_DISPLAY_HINTS = 21,
+	DPTX_APCALL_DEVICE_NOT_RESPONDING = 22,
+	DPTX_APCALL_DEVICE_BUSY_TIMEOUT = 23,
+	DPTX_APCALL_DEVICE_NOT_STARTED = 24,
 };
 
 #define DCPDPTX_REMOTE_PORT_CORE GENMASK(3, 0)

drivers/gpu/drm/apple/trace.h

@@ -52,6 +52,8 @@
 		{ DPTX_APCALL_GET_MAX_LINK_RATE, "get_max_link_rate" },       \
 		{ DPTX_APCALL_GET_LINK_RATE, "get_link_rate" },               \
 		{ DPTX_APCALL_SET_LINK_RATE, "set_link_rate" },               \
+		{ DPTX_APCALL_GET_MAX_LANE_COUNT,                             \
+		  "get_max_lane_count" },                                     \
 		{ DPTX_APCALL_GET_ACTIVE_LANE_COUNT,                          \
 		  "get_active_lane_count" },                                  \
 		{ DPTX_APCALL_SET_ACTIVE_LANE_COUNT,                          \