thunderbolt: Add support for maxhopid XDomain property

USB4 inter-domain spec mandates that the compatible hosts expose a new
property "maxhopid" that tells the connection manager on the other side
what is the maximum supported input HopID over the connection. Since
this is depend on the lane adapter the cable is connected it needs to be
filled in dynamically.

For this reason we take a copy of the global properties and fill then
for each XDomain connection upon first connect, and then keep updating
it if the generation changes as services are being added/removed. We
also take advantage of this copy to fill in the hostname.

We also expose this maxhopid as an attribute under each XDomain device.

While there drop kernel-doc entry for property_lock which seems to be
left there when the structure was originally introduced.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Documentation/ABI/testing/sysfs-bus-thunderbolt

@@ -134,6 +134,13 @@ Contact:	thunderbolt-software@lists.01.org
 Description:	This attribute contains name of this device extracted from
 		the device DROM.
 
+What:		/sys/bus/thunderbolt/devices/.../maxhopid
+Date:		Jul 2021
+KernelVersion:	5.13
+Contact:	Mika Westerberg <mika.westerberg@linux.intel.com>
+Description:	Only set for XDomains. The maximum HopID the other host
+		supports as its input HopID.
+
 What:		/sys/bus/thunderbolt/devices/.../rx_speed
 Date:		Jan 2020
 KernelVersion:	5.5

include/linux/thunderbolt.h

@@ -180,6 +180,8 @@ void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir);
  * @route: Route string the other domain can be reached
  * @vendor: Vendor ID of the remote domain
  * @device: Device ID of the demote domain
+ * @local_max_hopid: Maximum input HopID of this host
+ * @remote_max_hopid: Maximum input HopID of the remote host
  * @lock: Lock to serialize access to the following fields of this structure
  * @vendor_name: Name of the vendor (or %NULL if not known)
  * @device_name: Name of the device (or %NULL if not known)
@@ -193,9 +195,11 @@ void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir);
  * @receive_path: HopID which we expect the remote end to transmit
  * @receive_ring: Local ring (hop) where incoming packets arrive
  * @service_ids: Used to generate IDs for the services
- * @properties: Properties exported by the remote domain
- * @property_block_gen: Generation of @properties
- * @properties_lock: Lock protecting @properties.
+ * @local_property_block: Local block of properties
+ * @local_property_block_gen: Generation of @local_property_block
+ * @local_property_block_len: Length of the @local_property_block in dwords
+ * @remote_properties: Properties exported by the remote domain
+ * @remote_property_block_gen: Generation of @remote_properties
  * @get_uuid_work: Work used to retrieve @remote_uuid
  * @uuid_retries: Number of times left @remote_uuid is requested before
  *		  giving up
@@ -225,6 +229,8 @@ struct tb_xdomain {
 	u64 route;
 	u16 vendor;
 	u16 device;
+	unsigned int local_max_hopid;
+	unsigned int remote_max_hopid;
 	struct mutex lock;
 	const char *vendor_name;
 	const char *device_name;
@@ -237,8 +243,11 @@ struct tb_xdomain {
 	u16 receive_path;
 	u16 receive_ring;
 	struct ida service_ids;
-	struct tb_property_dir *properties;
-	u32 property_block_gen;
+	u32 *local_property_block;
+	u32 local_property_block_gen;
+	u32 local_property_block_len;
+	struct tb_property_dir *remote_properties;
+	u32 remote_property_block_gen;
 	struct delayed_work get_uuid_work;
 	int uuid_retries;
 	struct delayed_work get_properties_work;