diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index 3e01f41e9d66..0abdb69ee9f4 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -32,14 +32,15 @@ config USB4_DEBUGFS_WRITE
 	  this for production systems or distro kernels.
 
 config USB4_DEBUGFS_MARGINING
-	bool "Expose receiver lane margining operations under USB4 ports (DANGEROUS)"
+	bool "Expose receiver lane margining operations under USB4 ports and retimers (DANGEROUS)"
 	depends on DEBUG_FS
 	depends on USB4_DEBUGFS_WRITE
 	help
-	  Enables hardware and software based receiver lane margining support
-	  under each USB4 port. Used for electrical quality and robustness
-	  validation during manufacturing. Should not be enabled by distro
-	  kernels.
+	  Enables hardware and software based receiver lane margining
+	  support under each USB4 port and retimer, including retimers
+	  on the other side of the cable. Used for electrical quality
+	  and robustness validation during manufacturing. Should not be
+	  enabled by distro kernels.
 
 config USB4_KUNIT_TEST
 	bool "KUnit tests" if !KUNIT_ALL_TESTS
diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
index 87b2c91a4656..c2a735421609 100644
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -380,6 +380,9 @@ static ssize_t retimer_sb_regs_write(struct file *file,
 /**
  * struct tb_margining - Lane margining support
  * @port: USB4 port through which the margining operations are run
+ * @target: Sideband target
+ * @index: Retimer index if taget is %USB4_SB_TARGET_RETIMER
+ * @dev: Pointer to the device that is the target (USB4 port or retimer)
  * @caps: Port lane margining capabilities
  * @results: Last lane margining results
  * @lanes: %0, %1 or %7 (all)
@@ -397,6 +400,9 @@ static ssize_t retimer_sb_regs_write(struct file *file,
  */
 struct tb_margining {
 	struct tb_port *port;
+	enum usb4_sb_target target;
+	u8 index;
+	struct device *dev;
 	u32 caps[2];
 	u32 results[2];
 	unsigned int lanes;
@@ -736,6 +742,7 @@ static int margining_run_write(void *data, u64 val)
 {
 	struct tb_margining *margining = data;
 	struct tb_port *port = margining->port;
+	struct device *dev = margining->dev;
 	struct tb_switch *sw = port->sw;
 	struct tb_switch *down_sw;
 	struct tb *tb = sw->tb;
@@ -744,7 +751,7 @@ static int margining_run_write(void *data, u64 val)
 	if (val != 1)
 		return -EINVAL;
 
-	pm_runtime_get_sync(&sw->dev);
+	pm_runtime_get_sync(dev);
 
 	if (mutex_lock_interruptible(&tb->lock)) {
 		ret = -ERESTARTSYS;
@@ -772,24 +779,29 @@ static int margining_run_write(void *data, u64 val)
 	}
 
 	if (margining->software) {
-		tb_port_dbg(port, "running software %s lane margining for lanes %u\n",
-			    margining->time ? "time" : "voltage", margining->lanes);
-		ret = usb4_port_sw_margin(port, USB4_SB_TARGET_ROUTER, 0,
+		tb_port_dbg(port,
+			    "running software %s lane margining for %s lanes %u\n",
+			    margining->time ? "time" : "voltage", dev_name(dev),
+			    margining->lanes);
+		ret = usb4_port_sw_margin(port, margining->target, margining->index,
 					  margining->lanes, margining->time,
 					  margining->right_high,
 					  USB4_MARGIN_SW_COUNTER_CLEAR);
 		if (ret)
 			goto out_clx;
 
-		ret = usb4_port_sw_margin_errors(port, USB4_SB_TARGET_ROUTER, 0,
+		ret = usb4_port_sw_margin_errors(port, margining->target,
+						 margining->index,
 						 &margining->results[0]);
 	} else {
-		tb_port_dbg(port, "running hardware %s lane margining for lanes %u\n",
-			    margining->time ? "time" : "voltage", margining->lanes);
+		tb_port_dbg(port,
+			    "running hardware %s lane margining for %s lanes %u\n",
+			    margining->time ? "time" : "voltage", dev_name(dev),
+			    margining->lanes);
 		/* Clear the results */
 		margining->results[0] = 0;
 		margining->results[1] = 0;
-		ret = usb4_port_hw_margin(port, USB4_SB_TARGET_ROUTER, 0,
+		ret = usb4_port_hw_margin(port, margining->target, margining->index,
 					  margining->lanes, margining->ber_level,
 					  margining->time, margining->right_high,
 					  margining->results);
@@ -801,8 +813,8 @@ static int margining_run_write(void *data, u64 val)
 out_unlock:
 	mutex_unlock(&tb->lock);
 out_rpm_put:
-	pm_runtime_mark_last_busy(&sw->dev);
-	pm_runtime_put_autosuspend(&sw->dev);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
 
 	return ret;
 }
@@ -1044,33 +1056,29 @@ static int margining_margin_show(struct seq_file *s, void *not_used)
 }
 DEBUGFS_ATTR_RW(margining_margin);
 
-static void margining_port_init(struct tb_port *port)
+static struct tb_margining *margining_alloc(struct tb_port *port,
+					    struct device *dev,
+					    enum usb4_sb_target target,
+					    u8 index, struct dentry *parent)
 {
 	struct tb_margining *margining;
-	struct dentry *dir, *parent;
-	struct usb4_port *usb4;
-	char dir_name[10];
+	struct dentry *dir;
 	unsigned int val;
 	int ret;
 
-	usb4 = port->usb4;
-	if (!usb4)
-		return;
-
-	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
-	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
-
 	margining = kzalloc(sizeof(*margining), GFP_KERNEL);
 	if (!margining)
-		return;
+		return NULL;
 
 	margining->port = port;
+	margining->target = target;
+	margining->index = index;
+	margining->dev = dev;
 
-	ret = usb4_port_margining_caps(port, USB4_SB_TARGET_ROUTER, 0,
-				       margining->caps);
+	ret = usb4_port_margining_caps(port, target, index, margining->caps);
 	if (ret) {
 		kfree(margining);
-		return;
+		return NULL;
 	}
 
 	/* Set the initial mode */
@@ -1124,8 +1132,22 @@ static void margining_port_init(struct tb_port *port)
 	     independent_time_margins(margining) == USB4_MARGIN_CAP_1_TIME_LR))
 		debugfs_create_file("margin", 0600, dir, margining,
 				    &margining_margin_fops);
+	return margining;
+}
 
-	usb4->margining = margining;
+static void margining_port_init(struct tb_port *port)
+{
+	struct dentry *parent;
+	char dir_name[10];
+
+	if (!port->usb4)
+		return;
+
+	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
+	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
+	port->usb4->margining = margining_alloc(port, &port->usb4->dev,
+						USB4_SB_TARGET_ROUTER, 0,
+						parent);
 }
 
 static void margining_port_remove(struct tb_port *port)
@@ -1199,11 +1221,27 @@ static void margining_xdomain_remove(struct tb_xdomain *xd)
 	downstream = tb_port_at(xd->route, parent_sw);
 	margining_port_remove(downstream);
 }
+
+static void margining_retimer_init(struct tb_retimer *rt, struct dentry *debugfs_dir)
+{
+	rt->margining = margining_alloc(rt->port, &rt->dev,
+					USB4_SB_TARGET_RETIMER, rt->index,
+					debugfs_dir);
+}
+
+static void margining_retimer_remove(struct tb_retimer *rt)
+{
+	kfree(rt->margining);
+	rt->margining = NULL;
+}
 #else
 static inline void margining_switch_init(struct tb_switch *sw) { }
 static inline void margining_switch_remove(struct tb_switch *sw) { }
 static inline void margining_xdomain_init(struct tb_xdomain *xd) { }
 static inline void margining_xdomain_remove(struct tb_xdomain *xd) { }
+static inline void margining_retimer_init(struct tb_retimer *rt,
+					  struct dentry *debugfs_dir) { }
+static inline void margining_retimer_remove(struct tb_retimer *rt) { }
 #endif
 
 static int port_clear_all_counters(struct tb_port *port)
@@ -1864,6 +1902,7 @@ void tb_retimer_debugfs_init(struct tb_retimer *rt)
 	debugfs_dir = debugfs_create_dir(dev_name(&rt->dev), tb_debugfs_root);
 	debugfs_create_file("sb_regs", DEBUGFS_MODE, debugfs_dir, rt,
 			    &retimer_sb_regs_fops);
+	margining_retimer_init(rt, debugfs_dir);
 }
 
 /**
@@ -1875,6 +1914,7 @@ void tb_retimer_debugfs_init(struct tb_retimer *rt)
 void tb_retimer_debugfs_remove(struct tb_retimer *rt)
 {
 	debugfs_lookup_and_remove(dev_name(&rt->dev), tb_debugfs_root);
+	margining_retimer_remove(rt);
 }
 
 void tb_debugfs_init(void)
diff --git a/drivers/thunderbolt/retimer.c b/drivers/thunderbolt/retimer.c
index 8ce1dc7bbfad..721319329afa 100644
--- a/drivers/thunderbolt/retimer.c
+++ b/drivers/thunderbolt/retimer.c
@@ -14,7 +14,11 @@
 #include "sb_regs.h"
 #include "tb.h"
 
+#if IS_ENABLED(CONFIG_USB4_DEBUGFS_MARGINING)
 #define TB_MAX_RETIMER_INDEX	6
+#else
+#define TB_MAX_RETIMER_INDEX	2
+#endif
 
 /**
  * tb_retimer_nvm_read() - Read contents of retimer NVM
@@ -319,6 +323,8 @@ static ssize_t nvm_version_show(struct device *dev,
 
 	if (!rt->nvm)
 		ret = -EAGAIN;
+	else if (rt->no_nvm_upgrade)
+		ret = -EOPNOTSUPP;
 	else
 		ret = sysfs_emit(buf, "%x.%x\n", rt->nvm->major, rt->nvm->minor);
 
@@ -366,7 +372,8 @@ const struct device_type tb_retimer_type = {
 	.release = tb_retimer_release,
 };
 
-static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
+static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status,
+			  bool on_board)
 {
 	struct tb_retimer *rt;
 	u32 vendor, device;
@@ -388,13 +395,6 @@ static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
 		return ret;
 	}
 
-	/*
-	 * Check that it supports NVM operations. If not then don't add
-	 * the device at all.
-	 */
-	ret = usb4_port_retimer_nvm_sector_size(port, index);
-	if (ret < 0)
-		return ret;
 
 	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
 	if (!rt)
@@ -407,6 +407,13 @@ static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
 	rt->port = port;
 	rt->tb = port->sw->tb;
 
+	/*
+	 * Only support NVM upgrade for on-board retimers. The retimers
+	 * on the other side of the connection.
+	 */
+	if (!on_board || usb4_port_retimer_nvm_sector_size(port, index) <= 0)
+		rt->no_nvm_upgrade = true;
+
 	rt->dev.parent = &port->usb4->dev;
 	rt->dev.bus = &tb_bus_type;
 	rt->dev.type = &tb_retimer_type;
@@ -487,7 +494,7 @@ static struct tb_retimer *tb_port_find_retimer(struct tb_port *port, u8 index)
 int tb_retimer_scan(struct tb_port *port, bool add)
 {
 	u32 status[TB_MAX_RETIMER_INDEX + 1] = {};
-	int ret, i, last_idx = 0;
+	int ret, i, max, last_idx = 0;
 
 	/*
 	 * Send broadcast RT to make sure retimer indices facing this
@@ -522,26 +529,28 @@ int tb_retimer_scan(struct tb_port *port, bool add)
 			break;
 	}
 
-	tb_retimer_unset_inbound_sbtx(port);
-
-	if (!last_idx)
-		return 0;
-
-	/* Add on-board retimers if they do not exist already */
+	max = i;
 	ret = 0;
-	for (i = 1; i <= last_idx; i++) {
+
+	/* Add retimers if they do not exist already */
+	for (i = 1; i <= max; i++) {
 		struct tb_retimer *rt;
 
+		/* Skip cable retimers */
+		if (usb4_port_retimer_is_cable(port, i))
+			continue;
+
 		rt = tb_port_find_retimer(port, i);
 		if (rt) {
 			put_device(&rt->dev);
 		} else if (add) {
-			ret = tb_retimer_add(port, i, status[i]);
+			ret = tb_retimer_add(port, i, status[i], i <= last_idx);
 			if (ret && ret != -EOPNOTSUPP)
 				break;
 		}
 	}
 
+	tb_retimer_unset_inbound_sbtx(port);
 	return ret;
 }
 
diff --git a/drivers/thunderbolt/sb_regs.h b/drivers/thunderbolt/sb_regs.h
index b2a6add82161..a29ef3c19422 100644
--- a/drivers/thunderbolt/sb_regs.h
+++ b/drivers/thunderbolt/sb_regs.h
@@ -26,6 +26,7 @@ enum usb4_sb_opcode {
 	USB4_SB_OPCODE_SET_INBOUND_SBTX = 0x5055534c,		/* "LSUP" */
 	USB4_SB_OPCODE_UNSET_INBOUND_SBTX = 0x50555355,		/* "USUP" */
 	USB4_SB_OPCODE_QUERY_LAST_RETIMER = 0x5453414c,		/* "LAST" */
+	USB4_SB_OPCODE_QUERY_CABLE_RETIMER = 0x524c4243,	/* "CBLR" */
 	USB4_SB_OPCODE_GET_NVM_SECTOR_SIZE = 0x53534e47,	/* "GNSS" */
 	USB4_SB_OPCODE_NVM_SET_OFFSET = 0x53504f42,		/* "BOPS" */
 	USB4_SB_OPCODE_NVM_BLOCK_WRITE = 0x574b4c42,		/* "BLKW" */
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 2f3de3d3c2e0..b47f7873c847 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -329,6 +329,7 @@ struct usb4_port {
  * @nvm: Pointer to the NVM if the retimer has one (%NULL otherwise)
  * @no_nvm_upgrade: Prevent NVM upgrade of this retimer
  * @auth_status: Status of last NVM authentication
+ * @margining: Pointer to margining structure if enabled
  */
 struct tb_retimer {
 	struct device dev;
@@ -340,6 +341,9 @@ struct tb_retimer {
 	struct tb_nvm *nvm;
 	bool no_nvm_upgrade;
 	u32 auth_status;
+#ifdef CONFIG_USB4_DEBUGFS_MARGINING
+	struct tb_margining *margining;
+#endif
 };
 
 /**
@@ -1363,6 +1367,7 @@ int usb4_port_sw_margin_errors(struct tb_port *port, enum usb4_sb_target target,
 int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index);
 int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index);
 int usb4_port_retimer_is_last(struct tb_port *port, u8 index);
+int usb4_port_retimer_is_cable(struct tb_port *port, u8 index);
 int usb4_port_retimer_nvm_sector_size(struct tb_port *port, u8 index);
 int usb4_port_retimer_nvm_set_offset(struct tb_port *port, u8 index,
 				     unsigned int address);
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index d952de07493f..4d83b65afb5b 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1830,6 +1830,30 @@ int usb4_port_retimer_is_last(struct tb_port *port, u8 index)
 	return ret ? ret : metadata & 1;
 }
 
+/**
+ * usb4_port_retimer_is_cable() - Is the retimer cable retimer
+ * @port: USB4 port
+ * @index: Retimer index
+ *
+ * If the retimer at @index is last cable retimer this function returns
+ * %1 and %0 if it is on-board retimer. In case a retimer is not present
+ * at @index returns %-ENODEV. Otherwise returns negative errno.
+ */
+int usb4_port_retimer_is_cable(struct tb_port *port, u8 index)
+{
+	u32 metadata;
+	int ret;
+
+	ret = usb4_port_retimer_op(port, index, USB4_SB_OPCODE_QUERY_CABLE_RETIMER,
+				   500);
+	if (ret)
+		return ret;
+
+	ret = usb4_port_sb_read(port, USB4_SB_TARGET_RETIMER, index,
+				USB4_SB_METADATA, &metadata, sizeof(metadata));
+	return ret ? ret : metadata & 1;
+}
+
 /**
  * usb4_port_retimer_nvm_sector_size() - Read retimer NVM sector size
  * @port: USB4 port