diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
index ea80354c410a..43de2938d1e4 100644
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -38,6 +38,7 @@
 #define COUNTER_SET_LEN		3
 
 #define HW_MARGINING_DWORDS		3
+#define SW_MARGINING_DWORDS		4
 
 /*
  * USB4 spec doesn't specify dwell range, the range of 100 ms to 500 ms
@@ -496,7 +497,7 @@ struct tb_margining {
 	unsigned int gen;
 	bool asym_rx;
 	u32 caps[3];
-	u32 results[3];
+	u32 results[5];
 	enum usb4_margining_lane lanes;
 	unsigned int min_ber_level;
 	unsigned int max_ber_level;
@@ -614,6 +615,11 @@ supports_optional_voltage_offset_range(const struct tb_margining *margining)
 	return margining->caps[0] & USB4_MARGIN_CAP_0_OPT_VOLTAGE_SUPPORT;
 }
 
+static bool supports_extended_error_counter(const struct tb_margining *margining)
+{
+	return margining->caps[0] & USB4_MARGIN_CAP_0_EXT_ERR_COUNTER;
+}
+
 static ssize_t
 margining_ber_level_write(struct file *file, const char __user *user_buf,
 			   size_t count, loff_t *ppos)
@@ -703,6 +709,8 @@ static int margining_caps_show(struct seq_file *s, void *not_used)
 		ber_level_show(s, margining->max_ber_level);
 	} else {
 		seq_puts(s, "# hardware margining: no\n");
+		seq_printf(s, "# extended error counter: %s\n",
+			   str_yes_no(supports_extended_error_counter(margining)));
 	}
 
 	seq_printf(s, "# all lanes simultaneously: %s\n",
@@ -1157,10 +1165,16 @@ static int margining_run_sw(struct tb_margining *margining,
 {
 	u32 nsamples = margining->dwell_time / DWELL_SAMPLE_INTERVAL;
 	int ret, i;
+	u32 dwords;
 
 	if (params->error_counter != USB4_MARGIN_SW_ERROR_COUNTER_START)
 		goto out_stop_or_clear;
 
+	if (supports_extended_error_counter(margining))
+		dwords = SW_MARGINING_DWORDS;
+	else
+		dwords = 1;
+
 	ret = usb4_port_sw_margin(margining->port, margining->target, margining->index,
 				  params, margining->results);
 	if (ret)
@@ -1170,7 +1184,8 @@ static int margining_run_sw(struct tb_margining *margining,
 		u32 errors = 0;
 
 		ret = usb4_port_sw_margin_errors(margining->port, margining->target,
-						 margining->index, &margining->results[1]);
+						 margining->index, &margining->results[1],
+						 dwords);
 		if (ret) {
 			tb_port_warn(margining->port, "failed to read margining error counters\n");
 			break;
@@ -1450,18 +1465,30 @@ static int margining_results_show(struct seq_file *s, void *not_used)
 		u32 lane_errors, result;
 
 		seq_printf(s, "0x%08x\n", margining->results[1]);
+		if (supports_extended_error_counter(margining)) {
+			seq_printf(s, "0x%08x\n", margining->results[2]);
+			seq_printf(s, "0x%08x\n", margining->results[3]);
+			seq_printf(s, "0x%08x\n", margining->results[4]);
+		}
+
 
 		result = FIELD_GET(USB4_MARGIN_SW_LANES_MASK, margining->results[0]);
 		if (result == USB4_MARGINING_LANE_RX0 ||
 		    result == USB4_MARGINING_LANE_ALL) {
 			lane_errors = FIELD_GET(USB4_MARGIN_SW_ERR_COUNTER_LANE_0_MASK,
 						margining->results[1]);
+			if (supports_extended_error_counter(margining))
+				lane_errors |= FIELD_PREP(USB4_MARGIN_SW_EXT_ERR_COUNTER_MASK,
+							  margining->results[2]);
 			seq_printf(s, "# lane 0 errors: %u\n", lane_errors);
 		}
 		if (result == USB4_MARGINING_LANE_RX1 ||
 		    result == USB4_MARGINING_LANE_ALL) {
 			lane_errors = FIELD_GET(USB4_MARGIN_SW_ERR_COUNTER_LANE_1_MASK,
 						margining->results[1]);
+			if (supports_extended_error_counter(margining))
+				lane_errors |= FIELD_PREP(USB4_MARGIN_SW_EXT_ERR_COUNTER_MASK,
+							  margining->results[3]);
 			seq_printf(s, "# lane 1 errors: %u\n", lane_errors);
 		}
 		if (margining->asym_rx &&
@@ -1469,6 +1496,9 @@ static int margining_results_show(struct seq_file *s, void *not_used)
 		     result == USB4_MARGINING_LANE_ALL)) {
 			lane_errors = FIELD_GET(USB4_MARGIN_SW_ERR_COUNTER_LANE_2_MASK,
 						margining->results[1]);
+			if (supports_extended_error_counter(margining))
+				lane_errors |= FIELD_PREP(USB4_MARGIN_SW_EXT_ERR_COUNTER_MASK,
+							  margining->results[4]);
 			seq_printf(s, "# lane 2 errors: %u\n", lane_errors);
 		}
 	}
diff --git a/drivers/thunderbolt/sb_regs.h b/drivers/thunderbolt/sb_regs.h
index 5391502a4b87..b801f3a694be 100644
--- a/drivers/thunderbolt/sb_regs.h
+++ b/drivers/thunderbolt/sb_regs.h
@@ -59,6 +59,7 @@ enum usb4_sb_opcode {
 #define USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_MASK GENMASK(18, 13)
 #define USB4_MARGIN_CAP_0_OPT_VOLTAGE_SUPPORT	BIT(19)
 #define USB4_MARGIN_CAP_0_VOLT_STEPS_OPT_MASK	GENMASK(26, 20)
+#define USB4_MARGIN_CAP_0_EXT_ERR_COUNTER	BIT(28)
 #define USB4_MARGIN_CAP_1_MAX_VOLT_OFS_OPT_MASK GENMASK(7, 0)
 #define USB4_MARGIN_CAP_1_TIME_DESTR		BIT(8)
 #define USB4_MARGIN_CAP_1_TIME_INDP_MASK	GENMASK(10, 9)
@@ -108,5 +109,6 @@ enum usb4_sb_opcode {
 #define USB4_MARGIN_SW_ERR_COUNTER_LANE_0_MASK	GENMASK(3, 0)
 #define USB4_MARGIN_SW_ERR_COUNTER_LANE_1_MASK	GENMASK(7, 4)
 #define USB4_MARGIN_SW_ERR_COUNTER_LANE_2_MASK	GENMASK(11, 8)
+#define USB4_MARGIN_SW_EXT_ERR_COUNTER_MASK	GENMASK(15, 4)
 
 #endif
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index c112954ce3fd..e86845762e22 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -1442,7 +1442,7 @@ int usb4_port_sw_margin(struct tb_port *port, enum usb4_sb_target target,
 			u8 index, const struct usb4_port_margining_params *params,
 			u32 *results);
 int usb4_port_sw_margin_errors(struct tb_port *port, enum usb4_sb_target target,
-			       u8 index, u32 *errors);
+			       u8 index, u32 *errors, size_t dwords);
 
 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);
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 5fd4fe070f25..fe1b061f7055 100644
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -1826,13 +1826,14 @@ int usb4_port_sw_margin(struct tb_port *port, enum usb4_sb_target target,
  * @target: Sideband target
  * @index: Retimer index if target is %USB4_SB_TARGET_RETIMER
  * @errors: Error metadata is copied here.
+ * @dwords: Number of dwords to read error counter values
  *
  * This reads back the software margining error counters from the port.
  *
  * Return: %0 on success, negative errno otherwise.
  */
 int usb4_port_sw_margin_errors(struct tb_port *port, enum usb4_sb_target target,
-			       u8 index, u32 *errors)
+			       u8 index, u32 *errors, size_t dwords)
 {
 	int ret;
 
@@ -1842,7 +1843,7 @@ int usb4_port_sw_margin_errors(struct tb_port *port, enum usb4_sb_target target,
 		return ret;
 
 	return usb4_port_sb_read(port, target, index, USB4_SB_METADATA, errors,
-				 sizeof(*errors));
+				 sizeof(*errors) * dwords);
 }
 
 static inline int usb4_port_retimer_op(struct tb_port *port, u8 index,