Merge tag 'thunderbolt-for-v5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next

Mika writes:

thunderbolt: Changes for v5.17 merge window

This includes following Thunderbolt/USB4 changes for the v5.17 merge
window:

  * Enable low-power link state (CL0s) for USB4 and Intel Titan Ridge
    devices
  * Add support for TMU (Time Management Unit) uni-directional mode
  * Power management improvements (suspend-to-disk, runtime PM)
  * USB4 compatibility fixes
  * Minor fixes and cleanups.

All these have been in linux-next with no reported issues.

* tag 'thunderbolt-for-v5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt:
  thunderbolt: Add module parameter for CLx disabling
  thunderbolt: Enable CL0s for Intel Titan Ridge
  thunderbolt: Rename Intel TB_VSE_CAP_IECS capability
  thunderbolt: Implement TMU time disruption for Intel Titan Ridge
  thunderbolt: Move usb4_switch_wait_for_bit() to switch.c
  thunderbolt: Add CL0s support for USB4 routers
  thunderbolt: Add TMU uni-directional mode
  thunderbolt: Check return value of kmemdup() in icm_handle_event()
  thunderbolt: Do not dereference fwnode in struct device
  thunderbolt: Add debug logging of DisplayPort resource allocation
  thunderbolt: Do not program path HopIDs for USB4 routers
  thunderbolt: Do not allow subtracting more NFC credits than configured
  thunderbolt: Runtime resume USB4 port when retimers are scanned
  thunderbolt: Tear down existing tunnels when resuming from hibernate
  thunderbolt: Runtime PM activate both ends of the device link
  thunderbolt: xdomain: Avoid potential stack OOB read

15 files changed, 1203 insertions, 204 deletions

diff --git a/drivers/thunderbolt/acpi.c b/drivers/thunderbolt/acpi.c
index b67e72d5644b..79b5abf9d042 100644
--- a/drivers/thunderbolt/acpi.c
+++ b/drivers/thunderbolt/acpi.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/pm_runtime.h>
 
 #include "tb.h"
 
@@ -31,7 +32,7 @@ static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
 		return AE_OK;
 
 	/* It needs to reference this NHI */
-	if (nhi->pdev->dev.fwnode != args.fwnode)
+	if (dev_fwnode(&nhi->pdev->dev) != args.fwnode)
 		goto out_put;
 
 	/*
@@ -74,8 +75,18 @@ static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
 		 pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) {
 		const struct device_link *link;
 
+		/*
+		 * Make them both active first to make sure the NHI does
+		 * not runtime suspend before the consumer. The
+		 * pm_runtime_put() below then allows the consumer to
+		 * runtime suspend again (which then allows NHI runtime
+		 * suspend too now that the device link is established).
+		 */
+		pm_runtime_get_sync(&pdev->dev);
+
 		link = device_link_add(&pdev->dev, &nhi->pdev->dev,
 				       DL_FLAG_AUTOREMOVE_SUPPLIER |
+				       DL_FLAG_RPM_ACTIVE |
 				       DL_FLAG_PM_RUNTIME);
 		if (link) {
 			dev_dbg(&nhi->pdev->dev, "created link from %s\n",
@@ -84,6 +95,8 @@ static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
 			dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
 				 dev_name(&pdev->dev));
 		}
+
+		pm_runtime_put(&pdev->dev);
 	}
 
 out_put:
diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index 6255f1ef9599..fff0c740c8f3 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -1741,8 +1741,13 @@ static void icm_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
 	if (!n)
 		return;
 
-	INIT_WORK(&n->work, icm_handle_notification);
 	n->pkg = kmemdup(buf, size, GFP_KERNEL);
+	if (!n->pkg) {
+		kfree(n);
+		return;
+	}
+
+	INIT_WORK(&n->work, icm_handle_notification);
 	n->tb = tb;
 
 	queue_work(tb->wq, &n->work);
diff --git a/drivers/thunderbolt/lc.c b/drivers/thunderbolt/lc.c
index c178f0d7beab..53495a38b4eb 100644
--- a/drivers/thunderbolt/lc.c
+++ b/drivers/thunderbolt/lc.c
@@ -193,6 +193,30 @@ int tb_lc_start_lane_initialization(struct tb_port *port)
 	return tb_sw_write(sw, &ctrl, TB_CFG_SWITCH, cap + TB_LC_SX_CTRL, 1);
 }
 
+/**
+ * tb_lc_is_clx_supported() - Check whether CLx is supported by the lane adapter
+ * @port: Lane adapter
+ *
+ * TB_LC_LINK_ATTR_CPS bit reflects if the link supports CLx including
+ * active cables (if connected on the link).
+ */
+bool tb_lc_is_clx_supported(struct tb_port *port)
+{
+	struct tb_switch *sw = port->sw;
+	int cap, ret;
+	u32 val;
+
+	cap = find_port_lc_cap(port);
+	if (cap < 0)
+		return false;
+
+	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, cap + TB_LC_LINK_ATTR, 1);
+	if (ret)
+		return false;
+
+	return !!(val & TB_LC_LINK_ATTR_CPS);
+}
+
 static int tb_lc_set_wake_one(struct tb_switch *sw, unsigned int offset,
 			      unsigned int flags)
 {
diff --git a/drivers/thunderbolt/path.c b/drivers/thunderbolt/path.c
index 564e2f42cebd..299712accfe9 100644
--- a/drivers/thunderbolt/path.c
+++ b/drivers/thunderbolt/path.c
@@ -85,11 +85,12 @@ static int tb_path_find_src_hopid(struct tb_port *src,
  * @dst_hopid: HopID to the @dst (%-1 if don't care)
  * @last: Last port is filled here if not %NULL
  * @name: Name of the path
+ * @alloc_hopid: Allocate HopIDs for the ports
  *
  * Follows a path starting from @src and @src_hopid to the last output
- * port of the path. Allocates HopIDs for the visited ports. Call
- * tb_path_free() to release the path and allocated HopIDs when the path
- * is not needed anymore.
+ * port of the path. Allocates HopIDs for the visited ports (if
+ * @alloc_hopid is true). Call tb_path_free() to release the path and
+ * allocated HopIDs when the path is not needed anymore.
  *
  * Note function discovers also incomplete paths so caller should check
  * that the @dst port is the expected one. If it is not, the path can be
@@ -99,7 +100,8 @@ static int tb_path_find_src_hopid(struct tb_port *src,
  */
 struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 				 struct tb_port *dst, int dst_hopid,
-				 struct tb_port **last, const char *name)
+				 struct tb_port **last, const char *name,
+				 bool alloc_hopid)
 {
 	struct tb_port *out_port;
 	struct tb_regs_hop hop;
@@ -156,6 +158,7 @@ struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 	path->tb = src->sw->tb;
 	path->path_length = num_hops;
 	path->activated = true;
+	path->alloc_hopid = alloc_hopid;
 
 	path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);
 	if (!path->hops) {
@@ -177,13 +180,14 @@ struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 			goto err;
 		}
 
-		if (tb_port_alloc_in_hopid(p, h, h) < 0)
+		if (alloc_hopid && tb_port_alloc_in_hopid(p, h, h) < 0)
 			goto err;
 
 		out_port = &sw->ports[hop.out_port];
 		next_hop = hop.next_hop;
 
-		if (tb_port_alloc_out_hopid(out_port, next_hop, next_hop) < 0) {
+		if (alloc_hopid &&
+		    tb_port_alloc_out_hopid(out_port, next_hop, next_hop) < 0) {
 			tb_port_release_in_hopid(p, h);
 			goto err;
 		}
@@ -263,6 +267,8 @@ struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid,
 		return NULL;
 	}
 
+	path->alloc_hopid = true;
+
 	in_hopid = src_hopid;
 	out_port = NULL;
 
@@ -345,17 +351,19 @@ err:
  */
 void tb_path_free(struct tb_path *path)
 {
-	int i;
-
-	for (i = 0; i < path->path_length; i++) {
-		const struct tb_path_hop *hop = &path->hops[i];
-
-		if (hop->in_port)
-			tb_port_release_in_hopid(hop->in_port,
-						 hop->in_hop_index);
-		if (hop->out_port)
-			tb_port_release_out_hopid(hop->out_port,
-						  hop->next_hop_index);
+	if (path->alloc_hopid) {
+		int i;
+
+		for (i = 0; i < path->path_length; i++) {
+			const struct tb_path_hop *hop = &path->hops[i];
+
+			if (hop->in_port)
+				tb_port_release_in_hopid(hop->in_port,
+							 hop->in_hop_index);
+			if (hop->out_port)
+				tb_port_release_out_hopid(hop->out_port,
+							  hop->next_hop_index);
+		}
 	}
 
 	kfree(path->hops);
diff --git a/drivers/thunderbolt/retimer.c b/drivers/thunderbolt/retimer.c
index 722694052f4a..8c29bd556ae0 100644
--- a/drivers/thunderbolt/retimer.c
+++ b/drivers/thunderbolt/retimer.c
@@ -324,15 +324,10 @@ struct device_type tb_retimer_type = {
 
 static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
 {
-	struct usb4_port *usb4;
 	struct tb_retimer *rt;
 	u32 vendor, device;
 	int ret;
 
-	usb4 = port->usb4;
-	if (!usb4)
-		return -EINVAL;
-
 	ret = usb4_port_retimer_read(port, index, USB4_SB_VENDOR_ID, &vendor,
 				     sizeof(vendor));
 	if (ret) {
@@ -374,7 +369,7 @@ static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
 	rt->port = port;
 	rt->tb = port->sw->tb;
 
-	rt->dev.parent = &usb4->dev;
+	rt->dev.parent = &port->usb4->dev;
 	rt->dev.bus = &tb_bus_type;
 	rt->dev.type = &tb_retimer_type;
 	dev_set_name(&rt->dev, "%s:%u.%u", dev_name(&port->sw->dev),
@@ -453,6 +448,13 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 {
 	u32 status[TB_MAX_RETIMER_INDEX + 1] = {};
 	int ret, i, last_idx = 0;
+	struct usb4_port *usb4;
+
+	usb4 = port->usb4;
+	if (!usb4)
+		return 0;
+
+	pm_runtime_get_sync(&usb4->dev);
 
 	/*
 	 * Send broadcast RT to make sure retimer indices facing this
@@ -460,7 +462,7 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 	 */
 	ret = usb4_port_enumerate_retimers(port);
 	if (ret)
-		return ret;
+		goto out;
 
 	/*
 	 * Enable sideband channel for each retimer. We can do this
@@ -490,8 +492,10 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 			break;
 	}
 
-	if (!last_idx)
-		return 0;
+	if (!last_idx) {
+		ret = 0;
+		goto out;
+	}
 
 	/* Add on-board retimers if they do not exist already */
 	for (i = 1; i <= last_idx; i++) {
@@ -507,7 +511,11 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 		}
 	}
 
-	return 0;
+out:
+	pm_runtime_mark_last_busy(&usb4->dev);
+	pm_runtime_put_autosuspend(&usb4->dev);
+
+	return ret;
 }
 
 static int remove_retimer(struct device *dev, void *data)
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 3014146081c1..d026e305fe5d 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -13,6 +13,7 @@
 #include <linux/sched/signal.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
+#include <linux/module.h>
 
 #include "tb.h"
 
@@ -26,6 +27,10 @@ struct nvm_auth_status {
 	u32 status;
 };
 
+static bool clx_enabled = true;
+module_param_named(clx, clx_enabled, bool, 0444);
+MODULE_PARM_DESC(clx, "allow low power states on the high-speed lanes (default: true)");
+
 /*
  * Hold NVM authentication failure status per switch This information
  * needs to stay around even when the switch gets power cycled so we
@@ -623,6 +628,9 @@ int tb_port_add_nfc_credits(struct tb_port *port, int credits)
 		return 0;
 
 	nfc_credits = port->config.nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
+	if (credits < 0)
+		credits = max_t(int, -nfc_credits, credits);
+
 	nfc_credits += credits;
 
 	tb_port_dbg(port, "adding %d NFC credits to %lu", credits,
@@ -1319,7 +1327,9 @@ int tb_dp_port_hpd_clear(struct tb_port *port)
  * @aux_tx: AUX TX Hop ID
  * @aux_rx: AUX RX Hop ID
  *
- * Programs specified Hop IDs for DP IN/OUT port.
+ * Programs specified Hop IDs for DP IN/OUT port. Can be called for USB4
+ * router DP adapters too but does not program the values as the fields
+ * are read-only.
  */
 int tb_dp_port_set_hops(struct tb_port *port, unsigned int video,
 			unsigned int aux_tx, unsigned int aux_rx)
@@ -1327,6 +1337,9 @@ int tb_dp_port_set_hops(struct tb_port *port, unsigned int video,
 	u32 data[2];
 	int ret;
 
+	if (tb_switch_is_usb4(port->sw))
+		return 0;
+
 	ret = tb_port_read(port, data, TB_CFG_PORT,
 			   port->cap_adap + ADP_DP_CS_0, ARRAY_SIZE(data));
 	if (ret)
@@ -1449,6 +1462,40 @@ int tb_switch_reset(struct tb_switch *sw)
 	return res.err;
 }
 
+/**
+ * tb_switch_wait_for_bit() - Wait for specified value of bits in offset
+ * @sw: Router to read the offset value from
+ * @offset: Offset in the router config space to read from
+ * @bit: Bit mask in the offset to wait for
+ * @value: Value of the bits to wait for
+ * @timeout_msec: Timeout in ms how long to wait
+ *
+ * Wait till the specified bits in specified offset reach specified value.
+ * Returns %0 in case of success, %-ETIMEDOUT if the @value was not reached
+ * within the given timeout or a negative errno in case of failure.
+ */
+int tb_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit,
+			   u32 value, int timeout_msec)
+{
+	ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
+
+	do {
+		u32 val;
+		int ret;
+
+		ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
+		if (ret)
+			return ret;
+
+		if ((val & bit) == value)
+			return 0;
+
+		usleep_range(50, 100);
+	} while (ktime_before(ktime_get(), timeout));
+
+	return -ETIMEDOUT;
+}
+
 /*
  * tb_plug_events_active() - enable/disable plug events on a switch
  *
@@ -2186,10 +2233,18 @@ struct tb_switch *tb_switch_alloc(struct tb *tb, struct device *parent,
 	if (ret > 0)
 		sw->cap_plug_events = ret;
 
+	ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_TIME2);
+	if (ret > 0)
+		sw->cap_vsec_tmu = ret;
+
 	ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
 	if (ret > 0)
 		sw->cap_lc = ret;
 
+	ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_CP_LP);
+	if (ret > 0)
+		sw->cap_lp = ret;
+
 	/* Root switch is always authorized */
 	if (!route)
 		sw->authorized = true;
@@ -2996,6 +3051,13 @@ void tb_switch_suspend(struct tb_switch *sw, bool runtime)
 
 	tb_sw_dbg(sw, "suspending switch\n");
 
+	/*
+	 * Actually only needed for Titan Ridge but for simplicity can be
+	 * done for USB4 device too as CLx is re-enabled at resume.
+	 */
+	if (tb_switch_disable_clx(sw, TB_CL0S))
+		tb_sw_warn(sw, "failed to disable CLx on upstream port\n");
+
 	err = tb_plug_events_active(sw, false);
 	if (err)
 		return;
@@ -3048,9 +3110,20 @@ bool tb_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
  */
 int tb_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
 {
+	int ret;
+
 	if (tb_switch_is_usb4(sw))
-		return usb4_switch_alloc_dp_resource(sw, in);
-	return tb_lc_dp_sink_alloc(sw, in);
+		ret = usb4_switch_alloc_dp_resource(sw, in);
+	else
+		ret = tb_lc_dp_sink_alloc(sw, in);
+
+	if (ret)
+		tb_sw_warn(sw, "failed to allocate DP resource for port %d\n",
+			   in->port);
+	else
+		tb_sw_dbg(sw, "allocated DP resource for port %d\n", in->port);
+
+	return ret;
 }
 
 /**
@@ -3073,6 +3146,8 @@ void tb_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
 	if (ret)
 		tb_sw_warn(sw, "failed to de-allocate DP resource for port %d\n",
 			   in->port);
+	else
+		tb_sw_dbg(sw, "released DP resource for port %d\n", in->port);
 }
 
 struct tb_sw_lookup {
@@ -3202,3 +3277,415 @@ struct tb_port *tb_switch_find_port(struct tb_switch *sw,
 
 	return NULL;
 }
+
+static int __tb_port_pm_secondary_set(struct tb_port *port, bool secondary)
+{
+	u32 phy;
+	int ret;
+
+	ret = tb_port_read(port, &phy, TB_CFG_PORT,
+			   port->cap_phy + LANE_ADP_CS_1, 1);
+	if (ret)
+		return ret;
+
+	if (secondary)
+		phy |= LANE_ADP_CS_1_PMS;
+	else
+		phy &= ~LANE_ADP_CS_1_PMS;
+
+	return tb_port_write(port, &phy, TB_CFG_PORT,
+			     port->cap_phy + LANE_ADP_CS_1, 1);
+}
+
+static int tb_port_pm_secondary_enable(struct tb_port *port)
+{
+	return __tb_port_pm_secondary_set(port, true);
+}
+
+static int tb_port_pm_secondary_disable(struct tb_port *port)
+{
+	return __tb_port_pm_secondary_set(port, false);
+}
+
+static int tb_switch_pm_secondary_resolve(struct tb_switch *sw)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	struct tb_port *up, *down;
+	int ret;
+
+	if (!tb_route(sw))
+		return 0;
+
+	up = tb_upstream_port(sw);
+	down = tb_port_at(tb_route(sw), parent);
+	ret = tb_port_pm_secondary_enable(up);
+	if (ret)
+		return ret;
+
+	return tb_port_pm_secondary_disable(down);
+}
+
+/* Called for USB4 or Titan Ridge routers only */
+static bool tb_port_clx_supported(struct tb_port *port, enum tb_clx clx)
+{
+	u32 mask, val;
+	bool ret;
+
+	/* Don't enable CLx in case of two single-lane links */
+	if (!port->bonded && port->dual_link_port)
+		return false;
+
+	/* Don't enable CLx in case of inter-domain link */
+	if (port->xdomain)
+		return false;
+
+	if (tb_switch_is_usb4(port->sw)) {
+		if (!usb4_port_clx_supported(port))
+			return false;
+	} else if (!tb_lc_is_clx_supported(port)) {
+		return false;
+	}
+
+	switch (clx) {
+	case TB_CL0S:
+		/* CL0s support requires also CL1 support */
+		mask = LANE_ADP_CS_0_CL0S_SUPPORT | LANE_ADP_CS_0_CL1_SUPPORT;
+		break;
+
+	/* For now we support only CL0s. Not CL1, CL2 */
+	case TB_CL1:
+	case TB_CL2:
+	default:
+		return false;
+	}
+
+	ret = tb_port_read(port, &val, TB_CFG_PORT,
+			   port->cap_phy + LANE_ADP_CS_0, 1);
+	if (ret)
+		return false;
+
+	return !!(val & mask);
+}
+
+static inline bool tb_port_cl0s_supported(struct tb_port *port)
+{
+	return tb_port_clx_supported(port, TB_CL0S);
+}
+
+static int __tb_port_cl0s_set(struct tb_port *port, bool enable)
+{
+	u32 phy, mask;
+	int ret;
+
+	/* To enable CL0s also required to enable CL1 */
+	mask = LANE_ADP_CS_1_CL0S_ENABLE | LANE_ADP_CS_1_CL1_ENABLE;
+	ret = tb_port_read(port, &phy, TB_CFG_PORT,
+			   port->cap_phy + LANE_ADP_CS_1, 1);
+	if (ret)
+		return ret;
+
+	if (enable)
+		phy |= mask;
+	else
+		phy &= ~mask;
+
+	return tb_port_write(port, &phy, TB_CFG_PORT,
+			     port->cap_phy + LANE_ADP_CS_1, 1);
+}
+
+static int tb_port_cl0s_disable(struct tb_port *port)
+{
+	return __tb_port_cl0s_set(port, false);
+}
+
+static int tb_port_cl0s_enable(struct tb_port *port)
+{
+	return __tb_port_cl0s_set(port, true);
+}
+
+static int tb_switch_enable_cl0s(struct tb_switch *sw)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	bool up_cl0s_support, down_cl0s_support;
+	struct tb_port *up, *down;
+	int ret;
+
+	if (!tb_switch_is_clx_supported(sw))
+		return 0;
+
+	/*
+	 * Enable CLx for host router's downstream port as part of the
+	 * downstream router enabling procedure.
+	 */
+	if (!tb_route(sw))
+		return 0;
+
+	/* Enable CLx only for first hop router (depth = 1) */
+	if (tb_route(parent))
+		return 0;
+
+	ret = tb_switch_pm_secondary_resolve(sw);
+	if (ret)
+		return ret;
+
+	up = tb_upstream_port(sw);
+	down = tb_port_at(tb_route(sw), parent);
+
+	up_cl0s_support = tb_port_cl0s_supported(up);
+	down_cl0s_support = tb_port_cl0s_supported(down);
+
+	tb_port_dbg(up, "CL0s %ssupported\n",
+		    up_cl0s_support ? "" : "not ");
+	tb_port_dbg(down, "CL0s %ssupported\n",
+		    down_cl0s_support ? "" : "not ");
+
+	if (!up_cl0s_support || !down_cl0s_support)
+		return -EOPNOTSUPP;
+
+	ret = tb_port_cl0s_enable(up);
+	if (ret)
+		return ret;
+
+	ret = tb_port_cl0s_enable(down);
+	if (ret) {
+		tb_port_cl0s_disable(up);
+		return ret;
+	}
+
+	ret = tb_switch_mask_clx_objections(sw);
+	if (ret) {
+		tb_port_cl0s_disable(up);
+		tb_port_cl0s_disable(down);
+		return ret;
+	}
+
+	sw->clx = TB_CL0S;
+
+	tb_port_dbg(up, "CL0s enabled\n");
+	return 0;
+}
+
+/**
+ * tb_switch_enable_clx() - Enable CLx on upstream port of specified router
+ * @sw: Router to enable CLx for
+ * @clx: The CLx state to enable
+ *
+ * Enable CLx state only for first hop router. That is the most common
+ * use-case, that is intended for better thermal management, and so helps
+ * to improve performance. CLx is enabled only if both sides of the link
+ * support CLx, and if both sides of the link are not configured as two
+ * single lane links and only if the link is not inter-domain link. The
+ * complete set of conditions is descibed in CM Guide 1.0 section 8.1.
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_switch_enable_clx(struct tb_switch *sw, enum tb_clx clx)
+{
+	struct tb_switch *root_sw = sw->tb->root_switch;
+
+	if (!clx_enabled)
+		return 0;
+
+	/*
+	 * CLx is not enabled and validated on Intel USB4 platforms before
+	 * Alder Lake.
+	 */
+	if (root_sw->generation < 4 || tb_switch_is_tiger_lake(root_sw))
+		return 0;
+
+	switch (clx) {
+	case TB_CL0S:
+		return tb_switch_enable_cl0s(sw);
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int tb_switch_disable_cl0s(struct tb_switch *sw)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	struct tb_port *up, *down;
+	int ret;
+
+	if (!tb_switch_is_clx_supported(sw))
+		return 0;
+
+	/*
+	 * Disable CLx for host router's downstream port as part of the
+	 * downstream router enabling procedure.
+	 */
+	if (!tb_route(sw))
+		return 0;
+
+	/* Disable CLx only for first hop router (depth = 1) */
+	if (tb_route(parent))
+		return 0;
+
+	up = tb_upstream_port(sw);
+	down = tb_port_at(tb_route(sw), parent);
+	ret = tb_port_cl0s_disable(up);
+	if (ret)
+		return ret;
+
+	ret = tb_port_cl0s_disable(down);
+	if (ret)
+		return ret;
+
+	sw->clx = TB_CLX_DISABLE;
+
+	tb_port_dbg(up, "CL0s disabled\n");
+	return 0;
+}
+
+/**
+ * tb_switch_disable_clx() - Disable CLx on upstream port of specified router
+ * @sw: Router to disable CLx for
+ * @clx: The CLx state to disable
+ *
+ * Return: Returns 0 on success or an error code on failure.
+ */
+int tb_switch_disable_clx(struct tb_switch *sw, enum tb_clx clx)
+{
+	if (!clx_enabled)
+		return 0;
+
+	switch (clx) {
+	case TB_CL0S:
+		return tb_switch_disable_cl0s(sw);
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/**
+ * tb_switch_mask_clx_objections() - Mask CLx objections for a router
+ * @sw: Router to mask objections for
+ *
+ * Mask the objections coming from the second depth routers in order to
+ * stop these objections from interfering with the CLx states of the first
+ * depth link.
+ */
+int tb_switch_mask_clx_objections(struct tb_switch *sw)
+{
+	int up_port = sw->config.upstream_port_number;
+	u32 offset, val[2], mask_obj, unmask_obj;
+	int ret, i;
+
+	/* Only Titan Ridge of pre-USB4 devices support CLx states */
+	if (!tb_switch_is_titan_ridge(sw))
+		return 0;
+
+	if (!tb_route(sw))
+		return 0;
+
+	/*
+	 * In Titan Ridge there are only 2 dual-lane Thunderbolt ports:
+	 * Port A consists of lane adapters 1,2 and
+	 * Port B consists of lane adapters 3,4
+	 * If upstream port is A, (lanes are 1,2), we mask objections from
+	 * port B (lanes 3,4) and unmask objections from Port A and vice-versa.
+	 */
+	if (up_port == 1) {
+		mask_obj = TB_LOW_PWR_C0_PORT_B_MASK;
+		unmask_obj = TB_LOW_PWR_C1_PORT_A_MASK;
+		offset = TB_LOW_PWR_C1_CL1;
+	} else {
+		mask_obj = TB_LOW_PWR_C1_PORT_A_MASK;
+		unmask_obj = TB_LOW_PWR_C0_PORT_B_MASK;
+		offset = TB_LOW_PWR_C3_CL1;
+	}
+
+	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
+			 sw->cap_lp + offset, ARRAY_SIZE(val));
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(val); i++) {
+		val[i] |= mask_obj;
+		val[i] &= ~unmask_obj;
+	}
+
+	return tb_sw_write(sw, &val, TB_CFG_SWITCH,
+			   sw->cap_lp + offset, ARRAY_SIZE(val));
+}
+
+/*
+ * Can be used for read/write a specified PCIe bridge for any Thunderbolt 3
+ * device. For now used only for Titan Ridge.
+ */
+static int tb_switch_pcie_bridge_write(struct tb_switch *sw, unsigned int bridge,
+				       unsigned int pcie_offset, u32 value)
+{
+	u32 offset, command, val;
+	int ret;
+
+	if (sw->generation != 3)
+		return -EOPNOTSUPP;
+
+	offset = sw->cap_plug_events + TB_PLUG_EVENTS_PCIE_WR_DATA;
+	ret = tb_sw_write(sw, &value, TB_CFG_SWITCH, offset, 1);
+	if (ret)
+		return ret;
+
+	command = pcie_offset & TB_PLUG_EVENTS_PCIE_CMD_DW_OFFSET_MASK;
+	command |= BIT(bridge + TB_PLUG_EVENTS_PCIE_CMD_BR_SHIFT);
+	command |= TB_PLUG_EVENTS_PCIE_CMD_RD_WR_MASK;
+	command |= TB_PLUG_EVENTS_PCIE_CMD_COMMAND_VAL
+			<< TB_PLUG_EVENTS_PCIE_CMD_COMMAND_SHIFT;
+	command |= TB_PLUG_EVENTS_PCIE_CMD_REQ_ACK_MASK;
+
+	offset = sw->cap_plug_events + TB_PLUG_EVENTS_PCIE_CMD;
+
+	ret = tb_sw_write(sw, &command, TB_CFG_SWITCH, offset, 1);
+	if (ret)
+		return ret;
+
+	ret = tb_switch_wait_for_bit(sw, offset,
+				     TB_PLUG_EVENTS_PCIE_CMD_REQ_ACK_MASK, 0, 100);
+	if (ret)
+		return ret;
+
+	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
+	if (ret)
+		return ret;
+
+	if (val & TB_PLUG_EVENTS_PCIE_CMD_TIMEOUT_MASK)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+/**
+ * tb_switch_pcie_l1_enable() - Enable PCIe link to enter L1 state
+ * @sw: Router to enable PCIe L1
+ *
+ * For Titan Ridge switch to enter CLx state, its PCIe bridges shall enable
+ * entry to PCIe L1 state. Shall be called after the upstream PCIe tunnel
+ * was configured. Due to Intel platforms limitation, shall be called only
+ * for first hop switch.
+ */
+int tb_switch_pcie_l1_enable(struct tb_switch *sw)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	int ret;
+
+	if (!tb_route(sw))
+		return 0;
+
+	if (!tb_switch_is_titan_ridge(sw))
+		return 0;
+
+	/* Enable PCIe L1 enable only for first hop router (depth = 1) */
+	if (tb_route(parent))
+		return 0;
+
+	/* Write to downstream PCIe bridge #5 aka Dn4 */
+	ret = tb_switch_pcie_bridge_write(sw, 5, 0x143, 0x0c7806b1);
+	if (ret)
+		return ret;
+
+	/* Write to Upstream PCIe bridge #0 aka Up0 */
+	return tb_switch_pcie_bridge_write(sw, 0, 0x143, 0x0c5806b1);
+}
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 2897a77d44c3..cbd0ad85ffb1 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -105,10 +105,11 @@ static void tb_remove_dp_resources(struct tb_switch *sw)
 	}
 }
 
-static void tb_discover_tunnels(struct tb_switch *sw)
+static void tb_switch_discover_tunnels(struct tb_switch *sw,
+				       struct list_head *list,
+				       bool alloc_hopids)
 {
 	struct tb *tb = sw->tb;
-	struct tb_cm *tcm = tb_priv(tb);
 	struct tb_port *port;
 
 	tb_switch_for_each_port(sw, port) {
@@ -116,24 +117,41 @@ static void tb_discover_tunnels(struct tb_switch *sw)
 
 		switch (port->config.type) {
 		case TB_TYPE_DP_HDMI_IN:
-			tunnel = tb_tunnel_discover_dp(tb, port);
+			tunnel = tb_tunnel_discover_dp(tb, port, alloc_hopids);
 			break;
 
 		case TB_TYPE_PCIE_DOWN:
-			tunnel = tb_tunnel_discover_pci(tb, port);
+			tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids);
 			break;
 
 		case TB_TYPE_USB3_DOWN:
-			tunnel = tb_tunnel_discover_usb3(tb, port);
+			tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids);
 			break;
 
 		default:
 			break;
 		}
 
-		if (!tunnel)
-			continue;
+		if (tunnel)
+			list_add_tail(&tunnel->list, list);
+	}
+
+	tb_switch_for_each_port(sw, port) {
+		if (tb_port_has_remote(port)) {
+			tb_switch_discover_tunnels(port->remote->sw, list,
+						   alloc_hopids);
+		}
+	}
+}
 
+static void tb_discover_tunnels(struct tb *tb)
+{
+	struct tb_cm *tcm = tb_priv(tb);
+	struct tb_tunnel *tunnel;
+
+	tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true);
+
+	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 		if (tb_tunnel_is_pci(tunnel)) {
 			struct tb_switch *parent = tunnel->dst_port->sw;
 
@@ -146,13 +164,6 @@ static void tb_discover_tunnels(struct tb_switch *sw)
 			pm_runtime_get_sync(&tunnel->src_port->sw->dev);
 			pm_runtime_get_sync(&tunnel->dst_port->sw->dev);
 		}
-
-		list_add_tail(&tunnel->list, &tcm->tunnel_list);
-	}
-
-	tb_switch_for_each_port(sw, port) {
-		if (tb_port_has_remote(port))
-			tb_discover_tunnels(port->remote->sw);
 	}
 }
 
@@ -210,7 +221,7 @@ static int tb_enable_tmu(struct tb_switch *sw)
 	int ret;
 
 	/* If it is already enabled in correct mode, don't touch it */
-	if (tb_switch_tmu_is_enabled(sw))
+	if (tb_switch_tmu_hifi_is_enabled(sw, sw->tmu.unidirectional_request))
 		return 0;
 
 	ret = tb_switch_tmu_disable(sw);
@@ -658,6 +669,11 @@ static void tb_scan_port(struct tb_port *port)
 	tb_switch_lane_bonding_enable(sw);
 	/* Set the link configured */
 	tb_switch_configure_link(sw);
+	if (tb_switch_enable_clx(sw, TB_CL0S))
+		tb_sw_warn(sw, "failed to enable CLx on upstream port\n");
+
+	tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_HIFI,
+				tb_switch_is_clx_enabled(sw));
 
 	if (tb_enable_tmu(sw))
 		tb_sw_warn(sw, "failed to enable TMU\n");
@@ -1076,6 +1092,13 @@ static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
 		return -EIO;
 	}
 
+	/*
+	 * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it
+	 * here.
+	 */
+	if (tb_switch_pcie_l1_enable(sw))
+		tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n");
+
 	list_add_tail(&tunnel->list, &tcm->tunnel_list);
 	return 0;
 }
@@ -1364,12 +1387,13 @@ static int tb_start(struct tb *tb)
 		return ret;
 	}
 
+	tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_RATE_HIFI, false);
 	/* Enable TMU if it is off */
 	tb_switch_tmu_enable(tb->root_switch);
 	/* Full scan to discover devices added before the driver was loaded. */
 	tb_scan_switch(tb->root_switch);
 	/* Find out tunnels created by the boot firmware */
-	tb_discover_tunnels(tb->root_switch);
+	tb_discover_tunnels(tb);
 	/*
 	 * If the boot firmware did not create USB 3.x tunnels create them
 	 * now for the whole topology.
@@ -1407,6 +1431,14 @@ static void tb_restore_children(struct tb_switch *sw)
 	if (sw->is_unplugged)
 		return;
 
+	if (tb_switch_enable_clx(sw, TB_CL0S))
+		tb_sw_warn(sw, "failed to re-enable CLx on upstream port\n");
+
+	/*
+	 * tb_switch_tmu_configure() was already called when the switch was
+	 * added before entering system sleep or runtime suspend,
+	 * so no need to call it again before enabling TMU.
+	 */
 	if (tb_enable_tmu(sw))
 		tb_sw_warn(sw, "failed to restore TMU configuration\n");
 
@@ -1429,6 +1461,8 @@ static int tb_resume_noirq(struct tb *tb)
 {
 	struct tb_cm *tcm = tb_priv(tb);
 	struct tb_tunnel *tunnel, *n;
+	unsigned int usb3_delay = 0;
+	LIST_HEAD(tunnels);
 
 	tb_dbg(tb, "resuming...\n");
 
@@ -1439,8 +1473,31 @@ static int tb_resume_noirq(struct tb *tb)
 	tb_free_invalid_tunnels(tb);
 	tb_free_unplugged_children(tb->root_switch);
 	tb_restore_children(tb->root_switch);
-	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
+
+	/*
+	 * If we get here from suspend to disk the boot firmware or the
+	 * restore kernel might have created tunnels of its own. Since
+	 * we cannot be sure they are usable for us we find and tear
+	 * them down.
+	 */
+	tb_switch_discover_tunnels(tb->root_switch, &tunnels, false);
+	list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) {
+		if (tb_tunnel_is_usb3(tunnel))
+			usb3_delay = 500;
+		tb_tunnel_deactivate(tunnel);
+		tb_tunnel_free(tunnel);
+	}
+
+	/* Re-create our tunnels now */
+	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
+		/* USB3 requires delay before it can be re-activated */
+		if (tb_tunnel_is_usb3(tunnel)) {
+			msleep(usb3_delay);
+			/* Only need to do it once */
+			usb3_delay = 0;
+		}
 		tb_tunnel_restart(tunnel);
+	}
 	if (!list_empty(&tcm->tunnel_list)) {
 		/*
 		 * the pcie links need some time to get going.
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 725104c83e3d..74d3b14f004e 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -89,15 +89,31 @@ enum tb_switch_tmu_rate {
  * @cap: Offset to the TMU capability (%0 if not found)
  * @has_ucap: Does the switch support uni-directional mode
  * @rate: TMU refresh rate related to upstream switch. In case of root
- *	  switch this holds the domain rate.
+ *	  switch this holds the domain rate. Reflects the HW setting.
  * @unidirectional: Is the TMU in uni-directional or bi-directional mode
- *		    related to upstream switch. Don't case for root switch.
+ *		    related to upstream switch. Don't care for root switch.
+ *		    Reflects the HW setting.
+ * @unidirectional_request: Is the new TMU mode: uni-directional or bi-directional
+ *			    that is requested to be set. Related to upstream switch.
+ *			    Don't care for root switch.
+ * @rate_request: TMU new refresh rate related to upstream switch that is
+ *		  requested to be set. In case of root switch, this holds
+ *		  the new domain rate that is requested to be set.
  */
 struct tb_switch_tmu {
 	int cap;
 	bool has_ucap;
 	enum tb_switch_tmu_rate rate;
 	bool unidirectional;
+	bool unidirectional_request;
+	enum tb_switch_tmu_rate rate_request;
+};
+
+enum tb_clx {
+	TB_CLX_DISABLE,
+	TB_CL0S,
+	TB_CL1,
+	TB_CL2,
 };
 
 /**
@@ -122,7 +138,9 @@ struct tb_switch_tmu {
  * @link_usb4: Upstream link is USB4
  * @generation: Switch Thunderbolt generation
  * @cap_plug_events: Offset to the plug events capability (%0 if not found)
+ * @cap_vsec_tmu: Offset to the TMU vendor specific capability (%0 if not found)
  * @cap_lc: Offset to the link controller capability (%0 if not found)
+ * @cap_lp: Offset to the low power (CLx for TBT) capability (%0 if not found)
  * @is_unplugged: The switch is going away
  * @drom: DROM of the switch (%NULL if not found)
  * @nvm: Pointer to the NVM if the switch has one (%NULL otherwise)
@@ -148,6 +166,7 @@ struct tb_switch_tmu {
  * @min_dp_main_credits: Router preferred minimum number of buffers for DP MAIN
  * @max_pcie_credits: Router preferred number of buffers for PCIe
  * @max_dma_credits: Router preferred number of buffers for DMA/P2P
+ * @clx: CLx state on the upstream link of the router
  *
  * When the switch is being added or removed to the domain (other
  * switches) you need to have domain lock held.
@@ -172,7 +191,9 @@ struct tb_switch {
 	bool link_usb4;
 	unsigned int generation;
 	int cap_plug_events;
+	int cap_vsec_tmu;
 	int cap_lc;
+	int cap_lp;
 	bool is_unplugged;
 	u8 *drom;
 	struct tb_nvm *nvm;
@@ -196,6 +217,7 @@ struct tb_switch {
 	unsigned int min_dp_main_credits;
 	unsigned int max_pcie_credits;
 	unsigned int max_dma_credits;
+	enum tb_clx clx;
 };
 
 /**
@@ -354,6 +376,7 @@ enum tb_path_port {
  *	      when deactivating this path
  * @hops: Path hops
  * @path_length: How many hops the path uses
+ * @alloc_hopid: Does this path consume port HopID
  *
  * A path consists of a number of hops (see &struct tb_path_hop). To
  * establish a PCIe tunnel two paths have to be created between the two
@@ -374,6 +397,7 @@ struct tb_path {
 	bool clear_fc;
 	struct tb_path_hop *hops;
 	int path_length;
+	bool alloc_hopid;
 };
 
 /* HopIDs 0-7 are reserved by the Thunderbolt protocol */
@@ -740,6 +764,8 @@ void tb_switch_remove(struct tb_switch *sw);
 void tb_switch_suspend(struct tb_switch *sw, bool runtime);
 int tb_switch_resume(struct tb_switch *sw);
 int tb_switch_reset(struct tb_switch *sw);
+int tb_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit,
+			   u32 value, int timeout_msec);
 void tb_sw_set_unplugged(struct tb_switch *sw);
 struct tb_port *tb_switch_find_port(struct tb_switch *sw,
 				    enum tb_port_type type);
@@ -851,6 +877,20 @@ static inline bool tb_switch_is_titan_ridge(const struct tb_switch *sw)
 	return false;
 }
 
+static inline bool tb_switch_is_tiger_lake(const struct tb_switch *sw)
+{
+	if (sw->config.vendor_id == PCI_VENDOR_ID_INTEL) {
+		switch (sw->config.device_id) {
+		case PCI_DEVICE_ID_INTEL_TGL_NHI0:
+		case PCI_DEVICE_ID_INTEL_TGL_NHI1:
+		case PCI_DEVICE_ID_INTEL_TGL_H_NHI0:
+		case PCI_DEVICE_ID_INTEL_TGL_H_NHI1:
+			return true;
+		}
+	}
+	return false;
+}
+
 /**
  * tb_switch_is_usb4() - Is the switch USB4 compliant
  * @sw: Switch to check
@@ -889,13 +929,64 @@ int tb_switch_tmu_init(struct tb_switch *sw);
 int tb_switch_tmu_post_time(struct tb_switch *sw);
 int tb_switch_tmu_disable(struct tb_switch *sw);
 int tb_switch_tmu_enable(struct tb_switch *sw);
-
-static inline bool tb_switch_tmu_is_enabled(const struct tb_switch *sw)
+void tb_switch_tmu_configure(struct tb_switch *sw,
+			     enum tb_switch_tmu_rate rate,
+			     bool unidirectional);
+/**
+ * tb_switch_tmu_hifi_is_enabled() - Checks if the specified TMU mode is enabled
+ * @sw: Router whose TMU mode to check
+ * @unidirectional: If uni-directional (bi-directional otherwise)
+ *
+ * Return true if hardware TMU configuration matches the one passed in
+ * as parameter. That is HiFi and either uni-directional or bi-directional.
+ */
+static inline bool tb_switch_tmu_hifi_is_enabled(const struct tb_switch *sw,
+						 bool unidirectional)
 {
 	return sw->tmu.rate == TB_SWITCH_TMU_RATE_HIFI &&
-	       !sw->tmu.unidirectional;
+	       sw->tmu.unidirectional == unidirectional;
 }
 
+int tb_switch_enable_clx(struct tb_switch *sw, enum tb_clx clx);
+int tb_switch_disable_clx(struct tb_switch *sw, enum tb_clx clx);
+
+/**
+ * tb_switch_is_clx_enabled() - Checks if the CLx is enabled
+ * @sw: Router to check the CLx state for
+ *
+ * Checks if the CLx is enabled on the router upstream link.
+ * Not applicable for a host router.
+ */
+static inline bool tb_switch_is_clx_enabled(const struct tb_switch *sw)
+{
+	return sw->clx != TB_CLX_DISABLE;
+}
+
+/**
+ * tb_switch_is_cl0s_enabled() - Checks if the CL0s is enabled
+ * @sw: Router to check for the CL0s
+ *
+ * Checks if the CL0s is enabled on the router upstream link.
+ * Not applicable for a host router.
+ */
+static inline bool tb_switch_is_cl0s_enabled(const struct tb_switch *sw)
+{
+	return sw->clx == TB_CL0S;
+}
+
+/**
+ * tb_switch_is_clx_supported() - Is CLx supported on this type of router
+ * @sw: The router to check CLx support for
+ */
+static inline bool tb_switch_is_clx_supported(const struct tb_switch *sw)
+{
+	return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
+}
+
+int tb_switch_mask_clx_objections(struct tb_switch *sw);
+
+int tb_switch_pcie_l1_enable(struct tb_switch *sw);
+
 int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged);
 int tb_port_add_nfc_credits(struct tb_port *port, int credits);
 int tb_port_clear_counter(struct tb_port *port, int counter);
@@ -957,7 +1048,8 @@ int tb_dp_port_enable(struct tb_port *port, bool enable);
 
 struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid,
 				 struct tb_port *dst, int dst_hopid,
-				 struct tb_port **last, const char *name);
+				 struct tb_port **last, const char *name,
+				 bool alloc_hopid);
 struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid,
 			      struct tb_port *dst, int dst_hopid, int link_nr,
 			      const char *name);
@@ -988,6 +1080,7 @@ void tb_lc_unconfigure_port(struct tb_port *port);
 int tb_lc_configure_xdomain(struct tb_port *port);
 void tb_lc_unconfigure_xdomain(struct tb_port *port);
 int tb_lc_start_lane_initialization(struct tb_port *port);
+bool tb_lc_is_clx_supported(struct tb_port *port);
 int tb_lc_set_wake(struct tb_switch *sw, unsigned int flags);
 int tb_lc_set_sleep(struct tb_switch *sw);
 bool tb_lc_lane_bonding_possible(struct tb_switch *sw);
@@ -1074,6 +1167,7 @@ void usb4_port_unconfigure_xdomain(struct tb_port *port);
 int usb4_port_router_offline(struct tb_port *port);
 int usb4_port_router_online(struct tb_port *port);
 int usb4_port_enumerate_retimers(struct tb_port *port);
+bool usb4_port_clx_supported(struct tb_port *port);
 
 int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index);
 int usb4_port_retimer_read(struct tb_port *port, u8 index, u8 reg, void *buf,
diff --git a/drivers/thunderbolt/tb_msgs.h b/drivers/thunderbolt/tb_msgs.h
index bcabfcb2fd03..fe1afa44c56d 100644
--- a/drivers/thunderbolt/tb_msgs.h
+++ b/drivers/thunderbolt/tb_msgs.h
@@ -535,15 +535,25 @@ struct tb_xdp_header {
 	u32 type;
 };
 
+struct tb_xdp_error_response {
+	struct tb_xdp_header hdr;
+	u32 error;
+};
+
 struct tb_xdp_uuid {
 	struct tb_xdp_header hdr;
 };
 
 struct tb_xdp_uuid_response {
-	struct tb_xdp_header hdr;
-	uuid_t src_uuid;
-	u32 src_route_hi;
-	u32 src_route_lo;
+	union {
+		struct tb_xdp_error_response err;
+		struct {
+			struct tb_xdp_header hdr;
+			uuid_t src_uuid;
+			u32 src_route_hi;
+			u32 src_route_lo;
+		};
+	};
 };
 
 struct tb_xdp_properties {
@@ -555,13 +565,18 @@ struct tb_xdp_properties {
 };
 
 struct tb_xdp_properties_response {
-	struct tb_xdp_header hdr;
-	uuid_t src_uuid;
-	uuid_t dst_uuid;
-	u16 offset;
-	u16 data_length;
-	u32 generation;
-	u32 data[0];
+	union {
+		struct tb_xdp_error_response err;
+		struct {
+			struct tb_xdp_header hdr;
+			uuid_t src_uuid;
+			uuid_t dst_uuid;
+			u16 offset;
+			u16 data_length;
+			u32 generation;
+			u32 data[];
+		};
+	};
 };
 
 /*
@@ -580,7 +595,10 @@ struct tb_xdp_properties_changed {
 };
 
 struct tb_xdp_properties_changed_response {
-	struct tb_xdp_header hdr;
+	union {
+		struct tb_xdp_error_response err;
+		struct tb_xdp_header hdr;
+	};
 };
 
 enum tb_xdp_error {
@@ -591,9 +609,4 @@ enum tb_xdp_error {
 	ERROR_NOT_READY,
 };
 
-struct tb_xdp_error_response {
-	struct tb_xdp_header hdr;
-	u32 error;
-};
-
 #endif
diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
index 484f25be2849..a74f4878d3e7 100644
--- a/drivers/thunderbolt/tb_regs.h
+++ b/drivers/thunderbolt/tb_regs.h
@@ -33,7 +33,7 @@ enum tb_switch_cap {
 enum tb_switch_vse_cap {
 	TB_VSE_CAP_PLUG_EVENTS		= 0x01, /* also EEPROM */
 	TB_VSE_CAP_TIME2		= 0x03,
-	TB_VSE_CAP_IECS			= 0x04,
+	TB_VSE_CAP_CP_LP		= 0x04,
 	TB_VSE_CAP_LINK_CONTROLLER	= 0x06, /* also IECS */
 };
 
@@ -246,6 +246,7 @@ enum usb4_switch_op {
 #define TMU_RTR_CS_3_TS_PACKET_INTERVAL_SHIFT	16
 #define TMU_RTR_CS_22				0x16
 #define TMU_RTR_CS_24				0x18
+#define TMU_RTR_CS_25				0x19
 
 enum tb_port_type {
 	TB_TYPE_INACTIVE	= 0x000000,
@@ -305,16 +306,22 @@ struct tb_regs_port_header {
 /* TMU adapter registers */
 #define TMU_ADP_CS_3				0x03
 #define TMU_ADP_CS_3_UDM			BIT(29)
+#define TMU_ADP_CS_6				0x06
+#define TMU_ADP_CS_6_DTS			BIT(1)
 
 /* Lane adapter registers */
 #define LANE_ADP_CS_0				0x00
 #define LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK	GENMASK(25, 20)
 #define LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT	20
+#define LANE_ADP_CS_0_CL0S_SUPPORT		BIT(26)
+#define LANE_ADP_CS_0_CL1_SUPPORT		BIT(27)
 #define LANE_ADP_CS_1				0x01
 #define LANE_ADP_CS_1_TARGET_WIDTH_MASK		GENMASK(9, 4)
 #define LANE_ADP_CS_1_TARGET_WIDTH_SHIFT	4
 #define LANE_ADP_CS_1_TARGET_WIDTH_SINGLE	0x1
 #define LANE_ADP_CS_1_TARGET_WIDTH_DUAL		0x3
+#define LANE_ADP_CS_1_CL0S_ENABLE		BIT(10)
+#define LANE_ADP_CS_1_CL1_ENABLE		BIT(11)
 #define LANE_ADP_CS_1_LD			BIT(14)
 #define LANE_ADP_CS_1_LB			BIT(15)
 #define LANE_ADP_CS_1_CURRENT_SPEED_MASK	GENMASK(19, 16)
@@ -323,6 +330,7 @@ struct tb_regs_port_header {
 #define LANE_ADP_CS_1_CURRENT_SPEED_GEN3	0x4
 #define LANE_ADP_CS_1_CURRENT_WIDTH_MASK	GENMASK(25, 20)
 #define LANE_ADP_CS_1_CURRENT_WIDTH_SHIFT	20
+#define LANE_ADP_CS_1_PMS			BIT(30)
 
 /* USB4 port registers */
 #define PORT_CS_1				0x01
@@ -338,6 +346,7 @@ struct tb_regs_port_header {
 #define PORT_CS_18				0x12
 #define PORT_CS_18_BE				BIT(8)
 #define PORT_CS_18_TCM				BIT(9)
+#define PORT_CS_18_CPS				BIT(10)
 #define PORT_CS_18_WOU4S			BIT(18)
 #define PORT_CS_19				0x13
 #define PORT_CS_19_PC				BIT(3)
@@ -437,39 +446,79 @@ struct tb_regs_hop {
 	u32 unknown3:3; /* set to zero */
 } __packed;
 
+/* TMU Thunderbolt 3 registers */
+#define TB_TIME_VSEC_3_CS_9			0x9
+#define TB_TIME_VSEC_3_CS_9_TMU_OBJ_MASK	GENMASK(17, 16)
+#define TB_TIME_VSEC_3_CS_26			0x1a
+#define TB_TIME_VSEC_3_CS_26_TD			BIT(22)
+
+/*
+ * Used for Titan Ridge only. Bits are part of the same register: TMU_ADP_CS_6
+ * (see above) as in USB4 spec, but these specific bits used for Titan Ridge
+ * only and reserved in USB4 spec.
+ */
+#define TMU_ADP_CS_6_DISABLE_TMU_OBJ_MASK	GENMASK(3, 2)
+#define TMU_ADP_CS_6_DISABLE_TMU_OBJ_CL1	BIT(2)
+#define TMU_ADP_CS_6_DISABLE_TMU_OBJ_CL2	BIT(3)
+
+/* Plug Events registers */
+#define TB_PLUG_EVENTS_PCIE_WR_DATA		0x1b
+#define TB_PLUG_EVENTS_PCIE_CMD			0x1c
+#define TB_PLUG_EVENTS_PCIE_CMD_DW_OFFSET_MASK	GENMASK(9, 0)
+#define TB_PLUG_EVENTS_PCIE_CMD_BR_SHIFT	10
+#define TB_PLUG_EVENTS_PCIE_CMD_BR_MASK		GENMASK(17, 10)
+#define TB_PLUG_EVENTS_PCIE_CMD_RD_WR_MASK	BIT(21)
+#define TB_PLUG_EVENTS_PCIE_CMD_WR		0x1
+#define TB_PLUG_EVENTS_PCIE_CMD_COMMAND_SHIFT	22
+#define TB_PLUG_EVENTS_PCIE_CMD_COMMAND_MASK	GENMASK(24, 22)
+#define TB_PLUG_EVENTS_PCIE_CMD_COMMAND_VAL	0x2
+#define TB_PLUG_EVENTS_PCIE_CMD_REQ_ACK_MASK	BIT(30)
+#define TB_PLUG_EVENTS_PCIE_CMD_TIMEOUT_MASK	BIT(31)
+#define TB_PLUG_EVENTS_PCIE_CMD_RD_DATA		0x1d
+
+/* CP Low Power registers */
+#define TB_LOW_PWR_C1_CL1			0x1
+#define TB_LOW_PWR_C1_CL1_OBJ_MASK		GENMASK(4, 1)
+#define TB_LOW_PWR_C1_CL2_OBJ_MASK		GENMASK(4, 1)
+#define TB_LOW_PWR_C1_PORT_A_MASK		GENMASK(2, 1)
+#define TB_LOW_PWR_C0_PORT_B_MASK		GENMASK(4, 3)
+#define TB_LOW_PWR_C3_CL1			0x3
+
 /* Common link controller registers */
-#define TB_LC_DESC			0x02
-#define TB_LC_DESC_NLC_MASK		GENMASK(3, 0)
-#define TB_LC_DESC_SIZE_SHIFT		8
-#define TB_LC_DESC_SIZE_MASK		GENMASK(15, 8)
-#define TB_LC_DESC_PORT_SIZE_SHIFT	16
-#define TB_LC_DESC_PORT_SIZE_MASK	GENMASK(27, 16)
-#define TB_LC_FUSE			0x03
-#define TB_LC_SNK_ALLOCATION		0x10
-#define TB_LC_SNK_ALLOCATION_SNK0_MASK	GENMASK(3, 0)
-#define TB_LC_SNK_ALLOCATION_SNK0_CM	0x1
-#define TB_LC_SNK_ALLOCATION_SNK1_SHIFT	4
-#define TB_LC_SNK_ALLOCATION_SNK1_MASK	GENMASK(7, 4)
-#define TB_LC_SNK_ALLOCATION_SNK1_CM	0x1
-#define TB_LC_POWER			0x740
+#define TB_LC_DESC				0x02
+#define TB_LC_DESC_NLC_MASK			GENMASK(3, 0)
+#define TB_LC_DESC_SIZE_SHIFT			8
+#define TB_LC_DESC_SIZE_MASK			GENMASK(15, 8)
+#define TB_LC_DESC_PORT_SIZE_SHIFT		16
+#define TB_LC_DESC_PORT_SIZE_MASK		GENMASK(27, 16)
+#define TB_LC_FUSE				0x03
+#define TB_LC_SNK_ALLOCATION			0x10
+#define TB_LC_SNK_ALLOCATION_SNK0_MASK		GENMASK(3, 0)
+#define TB_LC_SNK_ALLOCATION_SNK0_CM		0x1
+#define TB_LC_SNK_ALLOCATION_SNK1_SHIFT		4
+#define TB_LC_SNK_ALLOCATION_SNK1_MASK		GENMASK(7, 4)
+#define TB_LC_SNK_ALLOCATION_SNK1_CM		0x1
+#define TB_LC_POWER				0x740
 
 /* Link controller registers */
-#define TB_LC_PORT_ATTR			0x8d
-#define TB_LC_PORT_ATTR_BE		BIT(12)
-
-#define TB_LC_SX_CTRL			0x96
-#define TB_LC_SX_CTRL_WOC		BIT(1)
-#define TB_LC_SX_CTRL_WOD		BIT(2)
-#define TB_LC_SX_CTRL_WODPC		BIT(3)
-#define TB_LC_SX_CTRL_WODPD		BIT(4)
-#define TB_LC_SX_CTRL_WOU4		BIT(5)
-#define TB_LC_SX_CTRL_WOP		BIT(6)
-#define TB_LC_SX_CTRL_L1C		BIT(16)
-#define TB_LC_SX_CTRL_L1D		BIT(17)
-#define TB_LC_SX_CTRL_L2C		BIT(20)
-#define TB_LC_SX_CTRL_L2D		BIT(21)
-#define TB_LC_SX_CTRL_SLI		BIT(29)
-#define TB_LC_SX_CTRL_UPSTREAM		BIT(30)
-#define TB_LC_SX_CTRL_SLP		BIT(31)
+#define TB_LC_PORT_ATTR				0x8d
+#define TB_LC_PORT_ATTR_BE			BIT(12)
+
+#define TB_LC_SX_CTRL				0x96
+#define TB_LC_SX_CTRL_WOC			BIT(1)
+#define TB_LC_SX_CTRL_WOD			BIT(2)
+#define TB_LC_SX_CTRL_WODPC			BIT(3)
+#define TB_LC_SX_CTRL_WODPD			BIT(4)
+#define TB_LC_SX_CTRL_WOU4			BIT(5)
+#define TB_LC_SX_CTRL_WOP			BIT(6)
+#define TB_LC_SX_CTRL_L1C			BIT(16)
+#define TB_LC_SX_CTRL_L1D			BIT(17)
+#define TB_LC_SX_CTRL_L2C			BIT(20)
+#define TB_LC_SX_CTRL_L2D			BIT(21)
+#define TB_LC_SX_CTRL_SLI			BIT(29)
+#define TB_LC_SX_CTRL_UPSTREAM			BIT(30)
+#define TB_LC_SX_CTRL_SLP			BIT(31)
+#define TB_LC_LINK_ATTR				0x97
+#define TB_LC_LINK_ATTR_CPS			BIT(18)
 
 #endif
diff --git a/drivers/thunderbolt/tmu.c b/drivers/thunderbolt/tmu.c
index 039c42a06000..e4a07a26f693 100644
--- a/drivers/thunderbolt/tmu.c
+++ b/drivers/thunderbolt/tmu.c
@@ -115,6 +115,11 @@ static inline int tb_port_tmu_unidirectional_disable(struct tb_port *port)
 	return tb_port_tmu_set_unidirectional(port, false);
 }
 
+static inline int tb_port_tmu_unidirectional_enable(struct tb_port *port)
+{
+	return tb_port_tmu_set_unidirectional(port, true);
+}
+
 static bool tb_port_tmu_is_unidirectional(struct tb_port *port)
 {
 	int ret;
@@ -128,23 +133,46 @@ static bool tb_port_tmu_is_unidirectional(struct tb_port *port)
 	return val & TMU_ADP_CS_3_UDM;
 }
 
+static int tb_port_tmu_time_sync(struct tb_port *port, bool time_sync)
+{
+	u32 val = time_sync ? TMU_ADP_CS_6_DTS : 0;
+
+	return tb_port_tmu_write(port, TMU_ADP_CS_6, TMU_ADP_CS_6_DTS, val);
+}
+
+static int tb_port_tmu_time_sync_disable(struct tb_port *port)
+{
+	return tb_port_tmu_time_sync(port, true);
+}
+
+static int tb_port_tmu_time_sync_enable(struct tb_port *port)
+{
+	return tb_port_tmu_time_sync(port, false);
+}
+
 static int tb_switch_tmu_set_time_disruption(struct tb_switch *sw, bool set)
 {
+	u32 val, offset, bit;
 	int ret;
-	u32 val;
 
-	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
-			 sw->tmu.cap + TMU_RTR_CS_0, 1);
+	if (tb_switch_is_usb4(sw)) {
+		offset = sw->tmu.cap + TMU_RTR_CS_0;
+		bit = TMU_RTR_CS_0_TD;
+	} else {
+		offset = sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_26;
+		bit = TB_TIME_VSEC_3_CS_26_TD;
+	}
+
+	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
 	if (ret)
 		return ret;
 
 	if (set)
-		val |= TMU_RTR_CS_0_TD;
+		val |= bit;
 	else
-		val &= ~TMU_RTR_CS_0_TD;
+		val &= ~bit;
 
-	return tb_sw_write(sw, &val, TB_CFG_SWITCH,
-			   sw->tmu.cap + TMU_RTR_CS_0, 1);
+	return tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 1);
 }
 
 /**
@@ -207,7 +235,8 @@ int tb_switch_tmu_init(struct tb_switch *sw)
  */
 int tb_switch_tmu_post_time(struct tb_switch *sw)
 {
-	unsigned int  post_local_time_offset, post_time_offset;
+	unsigned int post_time_high_offset, post_time_high = 0;
+	unsigned int post_local_time_offset, post_time_offset;
 	struct tb_switch *root_switch = sw->tb->root_switch;
 	u64 hi, mid, lo, local_time, post_time;
 	int i, ret, retries = 100;
@@ -247,6 +276,7 @@ int tb_switch_tmu_post_time(struct tb_switch *sw)
 
 	post_local_time_offset = sw->tmu.cap + TMU_RTR_CS_22;
 	post_time_offset = sw->tmu.cap + TMU_RTR_CS_24;
+	post_time_high_offset = sw->tmu.cap + TMU_RTR_CS_25;
 
 	/*
 	 * Write the Grandmaster time to the Post Local Time registers
@@ -258,17 +288,24 @@ int tb_switch_tmu_post_time(struct tb_switch *sw)
 		goto out;
 
 	/*
-	 * Have the new switch update its local time (by writing 1 to
-	 * the post_time registers) and wait for the completion of the
-	 * same (post_time register becomes 0). This means the time has
-	 * been converged properly.
+	 * Have the new switch update its local time by:
+	 * 1) writing 0x1 to the Post Time Low register and 0xffffffff to
+	 * Post Time High register.
+	 * 2) write 0 to Post Time High register and then wait for
+	 * the completion of the post_time register becomes 0.
+	 * This means the time has been converged properly.
 	 */
-	post_time = 1;
+	post_time = 0xffffffff00000001ULL;
 
 	ret = tb_sw_write(sw, &post_time, TB_CFG_SWITCH, post_time_offset, 2);
 	if (ret)
 		goto out;
 
+	ret = tb_sw_write(sw, &post_time_high, TB_CFG_SWITCH,
+			  post_time_high_offset, 1);
+	if (ret)
+		goto out;
+
 	do {
 		usleep_range(5, 10);
 		ret = tb_sw_read(sw, &post_time, TB_CFG_SWITCH,
@@ -297,30 +334,54 @@ out:
  */
 int tb_switch_tmu_disable(struct tb_switch *sw)
 {
-	int ret;
-
-	if (!tb_switch_is_usb4(sw))
+	/*
+	 * No need to disable TMU on devices that don't support CLx since
+	 * on these devices e.g. Alpine Ridge and earlier, the TMU mode
+	 * HiFi bi-directional is enabled by default and we don't change it.
+	 */
+	if (!tb_switch_is_clx_supported(sw))
 		return 0;
 
 	/* Already disabled? */
 	if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF)
 		return 0;
 
-	if (sw->tmu.unidirectional) {
+
+	if (tb_route(sw)) {
+		bool unidirectional = tb_switch_tmu_hifi_is_enabled(sw, true);
 		struct tb_switch *parent = tb_switch_parent(sw);
-		struct tb_port *up, *down;
+		struct tb_port *down, *up;
+		int ret;
 
-		up = tb_upstream_port(sw);
 		down = tb_port_at(tb_route(sw), parent);
-
-		/* The switch may be unplugged so ignore any errors */
-		tb_port_tmu_unidirectional_disable(up);
-		ret = tb_port_tmu_unidirectional_disable(down);
+		up = tb_upstream_port(sw);
+		/*
+		 * In case of uni-directional time sync, TMU handshake is
+		 * initiated by upstream router. In case of bi-directional
+		 * time sync, TMU handshake is initiated by downstream router.
+		 * Therefore, we change the rate to off in the respective
+		 * router.
+		 */
+		if (unidirectional)
+			tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_OFF);
+		else
+			tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
+
+		tb_port_tmu_time_sync_disable(up);
+		ret = tb_port_tmu_time_sync_disable(down);
 		if (ret)
 			return ret;
-	}
 
-	tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
+		if (unidirectional) {
+			/* The switch may be unplugged so ignore any errors */
+			tb_port_tmu_unidirectional_disable(up);
+			ret = tb_port_tmu_unidirectional_disable(down);
+			if (ret)
+				return ret;
+		}
+	} else {
+		tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
+	}
 
 	sw->tmu.unidirectional = false;
 	sw->tmu.rate = TB_SWITCH_TMU_RATE_OFF;
@@ -329,55 +390,231 @@ int tb_switch_tmu_disable(struct tb_switch *sw)
 	return 0;
 }
 
-/**
- * tb_switch_tmu_enable() - Enable TMU on a switch
- * @sw: Switch whose TMU to enable
- *
- * Enables TMU of a switch to be in bi-directional, HiFi mode. In this mode
- * all tunneling should work.
+static void __tb_switch_tmu_off(struct tb_switch *sw, bool unidirectional)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	struct tb_port *down, *up;
+
+	down = tb_port_at(tb_route(sw), parent);
+	up = tb_upstream_port(sw);
+	/*
+	 * In case of any failure in one of the steps when setting
+	 * bi-directional or uni-directional TMU mode, get back to the TMU
+	 * configurations in off mode. In case of additional failures in
+	 * the functions below, ignore them since the caller shall already
+	 * report a failure.
+	 */
+	tb_port_tmu_time_sync_disable(down);
+	tb_port_tmu_time_sync_disable(up);
+	if (unidirectional)
+		tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_OFF);
+	else
+		tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
+
+	tb_port_tmu_unidirectional_disable(down);
+	tb_port_tmu_unidirectional_disable(up);
+}
+
+/*
+ * This function is called when the previous TMU mode was
+ * TB_SWITCH_TMU_RATE_OFF.
  */
-int tb_switch_tmu_enable(struct tb_switch *sw)
+static int __tb_switch_tmu_enable_bidirectional(struct tb_switch *sw)
 {
+	struct tb_switch *parent = tb_switch_parent(sw);
+	struct tb_port *up, *down;
 	int ret;
 
-	if (!tb_switch_is_usb4(sw))
-		return 0;
+	up = tb_upstream_port(sw);
+	down = tb_port_at(tb_route(sw), parent);
 
-	if (tb_switch_tmu_is_enabled(sw))
-		return 0;
+	ret = tb_port_tmu_unidirectional_disable(up);
+	if (ret)
+		return ret;
 
-	ret = tb_switch_tmu_set_time_disruption(sw, true);
+	ret = tb_port_tmu_unidirectional_disable(down);
+	if (ret)
+		goto out;
+
+	ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI);
+	if (ret)
+		goto out;
+
+	ret = tb_port_tmu_time_sync_enable(up);
+	if (ret)
+		goto out;
+
+	ret = tb_port_tmu_time_sync_enable(down);
+	if (ret)
+		goto out;
+
+	return 0;
+
+out:
+	__tb_switch_tmu_off(sw, false);
+	return ret;
+}
+
+static int tb_switch_tmu_objection_mask(struct tb_switch *sw)
+{
+	u32 val;
+	int ret;
+
+	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH,
+			 sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_9, 1);
 	if (ret)
 		return ret;
 
-	/* Change mode to bi-directional */
-	if (tb_route(sw) && sw->tmu.unidirectional) {
-		struct tb_switch *parent = tb_switch_parent(sw);
-		struct tb_port *up, *down;
+	val &= ~TB_TIME_VSEC_3_CS_9_TMU_OBJ_MASK;
 
-		up = tb_upstream_port(sw);
-		down = tb_port_at(tb_route(sw), parent);
+	return tb_sw_write(sw, &val, TB_CFG_SWITCH,
+			   sw->cap_vsec_tmu + TB_TIME_VSEC_3_CS_9, 1);
+}
 
-		ret = tb_port_tmu_unidirectional_disable(down);
-		if (ret)
-			return ret;
+static int tb_switch_tmu_unidirectional_enable(struct tb_switch *sw)
+{
+	struct tb_port *up = tb_upstream_port(sw);
 
-		ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI);
+	return tb_port_tmu_write(up, TMU_ADP_CS_6,
+				 TMU_ADP_CS_6_DISABLE_TMU_OBJ_MASK,
+				 TMU_ADP_CS_6_DISABLE_TMU_OBJ_MASK);
+}
+
+/*
+ * This function is called when the previous TMU mode was
+ * TB_SWITCH_TMU_RATE_OFF.
+ */
+static int __tb_switch_tmu_enable_unidirectional(struct tb_switch *sw)
+{
+	struct tb_switch *parent = tb_switch_parent(sw);
+	struct tb_port *up, *down;
+	int ret;
+
+	up = tb_upstream_port(sw);
+	down = tb_port_at(tb_route(sw), parent);
+	ret = tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_HIFI);
+	if (ret)
+		return ret;
+
+	ret = tb_port_tmu_unidirectional_enable(up);
+	if (ret)
+		goto out;
+
+	ret = tb_port_tmu_time_sync_enable(up);
+	if (ret)
+		goto out;
+
+	ret = tb_port_tmu_unidirectional_enable(down);
+	if (ret)
+		goto out;
+
+	ret = tb_port_tmu_time_sync_enable(down);
+	if (ret)
+		goto out;
+
+	return 0;
+
+out:
+	__tb_switch_tmu_off(sw, true);
+	return ret;
+}
+
+static int tb_switch_tmu_hifi_enable(struct tb_switch *sw)
+{
+	bool unidirectional = sw->tmu.unidirectional_request;
+	int ret;
+
+	if (unidirectional && !sw->tmu.has_ucap)
+		return -EOPNOTSUPP;
+
+	/*
+	 * No need to enable TMU on devices that don't support CLx since on
+	 * these devices e.g. Alpine Ridge and earlier, the TMU mode HiFi
+	 * bi-directional is enabled by default.
+	 */
+	if (!tb_switch_is_clx_supported(sw))
+		return 0;
+
+	if (tb_switch_tmu_hifi_is_enabled(sw, sw->tmu.unidirectional_request))
+		return 0;
+
+	if (tb_switch_is_titan_ridge(sw) && unidirectional) {
+		/* Titan Ridge supports only CL0s */
+		if (!tb_switch_is_cl0s_enabled(sw))
+			return -EOPNOTSUPP;
+
+		ret = tb_switch_tmu_objection_mask(sw);
 		if (ret)
 			return ret;
 
-		ret = tb_port_tmu_unidirectional_disable(up);
+		ret = tb_switch_tmu_unidirectional_enable(sw);
 		if (ret)
 			return ret;
+	}
+
+	ret = tb_switch_tmu_set_time_disruption(sw, true);
+	if (ret)
+		return ret;
+
+	if (tb_route(sw)) {
+		/* The used mode changes are from OFF to HiFi-Uni/HiFi-BiDir */
+		if (sw->tmu.rate == TB_SWITCH_TMU_RATE_OFF) {
+			if (unidirectional)
+				ret = __tb_switch_tmu_enable_unidirectional(sw);
+			else
+				ret = __tb_switch_tmu_enable_bidirectional(sw);
+			if (ret)
+				return ret;
+		}
+		sw->tmu.unidirectional = unidirectional;
 	} else {
+		/*
+		 * Host router port configurations are written as
+		 * part of configurations for downstream port of the parent
+		 * of the child node - see above.
+		 * Here only the host router' rate configuration is written.
+		 */
 		ret = tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_HIFI);
 		if (ret)
 			return ret;
 	}
 
-	sw->tmu.unidirectional = false;
 	sw->tmu.rate = TB_SWITCH_TMU_RATE_HIFI;
-	tb_sw_dbg(sw, "TMU: mode set to: %s\n", tb_switch_tmu_mode_name(sw));
 
+	tb_sw_dbg(sw, "TMU: mode set to: %s\n", tb_switch_tmu_mode_name(sw));
 	return tb_switch_tmu_set_time_disruption(sw, false);
 }
+
+/**
+ * tb_switch_tmu_enable() - Enable TMU on a router
+ * @sw: Router whose TMU to enable
+ *
+ * Enables TMU of a router to be in uni-directional or bi-directional HiFi mode.
+ * Calling tb_switch_tmu_configure() is required before calling this function,
+ * to select the mode HiFi and directionality (uni-directional/bi-directional).
+ * In both modes all tunneling should work. Uni-directional mode is required for
+ * CLx (Link Low-Power) to work.
+ */
+int tb_switch_tmu_enable(struct tb_switch *sw)
+{
+	if (sw->tmu.rate_request == TB_SWITCH_TMU_RATE_NORMAL)
+		return -EOPNOTSUPP;
+
+	return tb_switch_tmu_hifi_enable(sw);
+}
+
+/**
+ * tb_switch_tmu_configure() - Configure the TMU rate and directionality
+ * @sw: Router whose mode to change
+ * @rate: Rate to configure Off/LowRes/HiFi
+ * @unidirectional: If uni-directional (bi-directional otherwise)
+ *
+ * Selects the rate of the TMU and directionality (uni-directional or
+ * bi-directional). Must be called before tb_switch_tmu_enable().
+ */
+void tb_switch_tmu_configure(struct tb_switch *sw,
+			     enum tb_switch_tmu_rate rate, bool unidirectional)
+{
+	sw->tmu.unidirectional_request = unidirectional;
+	sw->tmu.rate_request = rate;
+}
diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c
index bb5cc480fc9a..a473cc7d9a8d 100644
--- a/drivers/thunderbolt/tunnel.c
+++ b/drivers/thunderbolt/tunnel.c
@@ -207,12 +207,14 @@ static int tb_pci_init_path(struct tb_path *path)
  * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
  * @tb: Pointer to the domain structure
  * @down: PCIe downstream adapter
+ * @alloc_hopid: Allocate HopIDs from visited ports
  *
  * If @down adapter is active, follows the tunnel to the PCIe upstream
  * adapter and back. Returns the discovered tunnel or %NULL if there was
  * no tunnel.
  */
-struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
+struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down,
+					 bool alloc_hopid)
 {
 	struct tb_tunnel *tunnel;
 	struct tb_path *path;
@@ -233,7 +235,7 @@ struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
 	 * case.
 	 */
 	path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
-				&tunnel->dst_port, "PCIe Up");
+				&tunnel->dst_port, "PCIe Up", alloc_hopid);
 	if (!path) {
 		/* Just disable the downstream port */
 		tb_pci_port_enable(down, false);
@@ -244,7 +246,7 @@ struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
 		goto err_free;
 
 	path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
-				"PCIe Down");
+				"PCIe Down", alloc_hopid);
 	if (!path)
 		goto err_deactivate;
 	tunnel->paths[TB_PCI_PATH_DOWN] = path;
@@ -761,6 +763,7 @@ static int tb_dp_init_video_path(struct tb_path *path)
  * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
  * @tb: Pointer to the domain structure
  * @in: DP in adapter
+ * @alloc_hopid: Allocate HopIDs from visited ports
  *
  * If @in adapter is active, follows the tunnel to the DP out adapter
  * and back. Returns the discovered tunnel or %NULL if there was no
@@ -768,7 +771,8 @@ static int tb_dp_init_video_path(struct tb_path *path)
  *
  * Return: DP tunnel or %NULL if no tunnel found.
  */
-struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
+struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
+					bool alloc_hopid)
 {
 	struct tb_tunnel *tunnel;
 	struct tb_port *port;
@@ -787,7 +791,7 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
 	tunnel->src_port = in;
 
 	path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
-				&tunnel->dst_port, "Video");
+				&tunnel->dst_port, "Video", alloc_hopid);
 	if (!path) {
 		/* Just disable the DP IN port */
 		tb_dp_port_enable(in, false);
@@ -797,14 +801,15 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
 	if (tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT]))
 		goto err_free;
 
-	path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
+	path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX",
+				alloc_hopid);
 	if (!path)
 		goto err_deactivate;
 	tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
 	tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
 
 	path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
-				&port, "AUX RX");
+				&port, "AUX RX", alloc_hopid);
 	if (!path)
 		goto err_deactivate;
 	tunnel->paths[TB_DP_AUX_PATH_IN] = path;
@@ -1343,12 +1348,14 @@ static void tb_usb3_init_path(struct tb_path *path)
  * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
  * @tb: Pointer to the domain structure
  * @down: USB3 downstream adapter
+ * @alloc_hopid: Allocate HopIDs from visited ports
  *
  * If @down adapter is active, follows the tunnel to the USB3 upstream
  * adapter and back. Returns the discovered tunnel or %NULL if there was
  * no tunnel.
  */
-struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
+struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down,
+					  bool alloc_hopid)
 {
 	struct tb_tunnel *tunnel;
 	struct tb_path *path;
@@ -1369,7 +1376,7 @@ struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
 	 * case.
 	 */
 	path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
-				&tunnel->dst_port, "USB3 Down");
+				&tunnel->dst_port, "USB3 Down", alloc_hopid);
 	if (!path) {
 		/* Just disable the downstream port */
 		tb_usb3_port_enable(down, false);
@@ -1379,7 +1386,7 @@ struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
 	tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
 
 	path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
-				"USB3 Up");
+				"USB3 Up", alloc_hopid);
 	if (!path)
 		goto err_deactivate;
 	tunnel->paths[TB_USB3_PATH_UP] = path;
diff --git a/drivers/thunderbolt/tunnel.h b/drivers/thunderbolt/tunnel.h
index eea14e24f7e0..03e56076b5bc 100644
--- a/drivers/thunderbolt/tunnel.h
+++ b/drivers/thunderbolt/tunnel.h
@@ -64,10 +64,12 @@ struct tb_tunnel {
 	int allocated_down;
 };
 
-struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down);
+struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down,
+					 bool alloc_hopid);
 struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
 				      struct tb_port *down);
-struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in);
+struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
+					bool alloc_hopid);
 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
 				     struct tb_port *out, int max_up,
 				     int max_down);
@@ -77,7 +79,8 @@ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
 				      int receive_ring);
 bool tb_tunnel_match_dma(const struct tb_tunnel *tunnel, int transmit_path,
 			 int transmit_ring, int receive_path, int receive_ring);
-struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down);
+struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down,
+					  bool alloc_hopid);
 struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
 				       struct tb_port *down, int max_up,
 				       int max_down);
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index ceddbe7e9f93..3a2e7126db9d 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -50,28 +50,6 @@ enum usb4_ba_index {
 #define USB4_BA_VALUE_MASK		GENMASK(31, 16)
 #define USB4_BA_VALUE_SHIFT		16
 
-static int usb4_switch_wait_for_bit(struct tb_switch *sw, u32 offset, u32 bit,
-				    u32 value, int timeout_msec)
-{
-	ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
-
-	do {
-		u32 val;
-		int ret;
-
-		ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, offset, 1);
-		if (ret)
-			return ret;
-
-		if ((val & bit) == value)
-			return 0;
-
-		usleep_range(50, 100);
-	} while (ktime_before(ktime_get(), timeout));
-
-	return -ETIMEDOUT;
-}
-
 static int usb4_native_switch_op(struct tb_switch *sw, u16 opcode,
 				 u32 *metadata, u8 *status,
 				 const void *tx_data, size_t tx_dwords,
@@ -97,7 +75,7 @@ static int usb4_native_switch_op(struct tb_switch *sw, u16 opcode,
 	if (ret)
 		return ret;
 
-	ret = usb4_switch_wait_for_bit(sw, ROUTER_CS_26, ROUTER_CS_26_OV, 0, 500);
+	ret = tb_switch_wait_for_bit(sw, ROUTER_CS_26, ROUTER_CS_26_OV, 0, 500);
 	if (ret)
 		return ret;
 
@@ -303,8 +281,8 @@ int usb4_switch_setup(struct tb_switch *sw)
 	if (ret)
 		return ret;
 
-	return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_CR,
-					ROUTER_CS_6_CR, 50);
+	return tb_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_CR,
+				      ROUTER_CS_6_CR, 50);
 }
 
 /**
@@ -480,8 +458,8 @@ int usb4_switch_set_sleep(struct tb_switch *sw)
 	if (ret)
 		return ret;
 
-	return usb4_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_SLPR,
-					ROUTER_CS_6_SLPR, 500);
+	return tb_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_SLPR,
+				      ROUTER_CS_6_SLPR, 500);
 }
 
 /**
@@ -1386,6 +1364,26 @@ int usb4_port_enumerate_retimers(struct tb_port *port)
 				  USB4_SB_OPCODE, &val, sizeof(val));
 }
 
+/**
+ * usb4_port_clx_supported() - Check if CLx is supported by the link
+ * @port: Port to check for CLx support for
+ *
+ * PORT_CS_18_CPS bit reflects if the link supports CLx including
+ * active cables (if connected on the link).
+ */
+bool usb4_port_clx_supported(struct tb_port *port)
+{
+	int ret;
+	u32 val;
+
+	ret = tb_port_read(port, &val, TB_CFG_PORT,
+			   port->cap_usb4 + PORT_CS_18, 1);
+	if (ret)
+		return false;
+
+	return !!(val & PORT_CS_18_CPS);
+}
+
 static inline int usb4_port_retimer_op(struct tb_port *port, u8 index,
 				       enum usb4_sb_opcode opcode,
 				       int timeout_msec)
diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
index eff32499610f..01d6b724ca51 100644
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -214,16 +214,12 @@ static inline void tb_xdp_fill_header(struct tb_xdp_header *hdr, u64 route,
 	memcpy(&hdr->uuid, &tb_xdp_uuid, sizeof(tb_xdp_uuid));
 }
 
-static int tb_xdp_handle_error(const struct tb_xdp_header *hdr)
+static int tb_xdp_handle_error(const struct tb_xdp_error_response *res)
 {
-	const struct tb_xdp_error_response *error;
-
-	if (hdr->type != ERROR_RESPONSE)
+	if (res->hdr.type != ERROR_RESPONSE)
 		return 0;
 
-	error = (const struct tb_xdp_error_response *)hdr;
-
-	switch (error->error) {
+	switch (res->error) {
 	case ERROR_UNKNOWN_PACKET:
 	case ERROR_UNKNOWN_DOMAIN:
 		return -EIO;
@@ -257,7 +253,7 @@ static int tb_xdp_uuid_request(struct tb_ctl *ctl, u64 route, int retry,
 	if (ret)
 		return ret;
 
-	ret = tb_xdp_handle_error(&res.hdr);
+	ret = tb_xdp_handle_error(&res.err);
 	if (ret)
 		return ret;
 
@@ -329,7 +325,7 @@ static int tb_xdp_properties_request(struct tb_ctl *ctl, u64 route,
 		if (ret)
 			goto err;
 
-		ret = tb_xdp_handle_error(&res->hdr);
+		ret = tb_xdp_handle_error(&res->err);
 		if (ret)
 			goto err;
 
@@ -462,7 +458,7 @@ static int tb_xdp_properties_changed_request(struct tb_ctl *ctl, u64 route,
 	if (ret)
 		return ret;
 
-	return tb_xdp_handle_error(&res.hdr);
+	return tb_xdp_handle_error(&res.err);
 }
 
 static int