diff mbox series

[v2,4/6] thunderbolt: Split out margining from USB4 port

Message ID 20240614121512.1361184-5-mika.westerberg@linux.intel.com
State New
Headers show
Series thunderbolt: Sideband access and retimer lane margining support | expand

Commit Message

Mika Westerberg June 14, 2024, 12:15 p.m. UTC 
We are going to expand lane margining support for retimers too so split
out the generic margining functionality out of being specific to USB4
ports.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
 drivers/thunderbolt/debugfs.c | 234 ++++++++++++++++------------------
 1 file changed, 112 insertions(+), 122 deletions(-)
diff mbox series

Patch

diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
index 5196ece2ded7..0e871c7ae9c0 100644
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -379,6 +379,7 @@  static ssize_t retimer_sb_regs_write(struct file *file,
 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_MARGINING)
 /**
  * struct tb_margining - Lane margining support
+ * @port: USB4 port through which the margining operations are run
  * @caps: Port lane margining capabilities
  * @results: Last lane margining results
  * @lanes: %0, %1 or %7 (all)
@@ -395,6 +396,7 @@  static ssize_t retimer_sb_regs_write(struct file *file,
  *		right/high
  */
 struct tb_margining {
+	struct tb_port *port;
 	u32 caps[2];
 	u32 results[2];
 	unsigned int lanes;
@@ -410,36 +412,38 @@  struct tb_margining {
 	bool right_high;
 };
 
-static bool supports_software(const struct usb4_port *usb4)
+static bool supports_software(const struct tb_margining *margining)
 {
-	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_SW;
+	return margining->caps[0] & USB4_MARGIN_CAP_0_MODES_SW;
 }
 
-static bool supports_hardware(const struct usb4_port *usb4)
+static bool supports_hardware(const struct tb_margining *margining)
 {
-	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_HW;
+	return margining->caps[0] & USB4_MARGIN_CAP_0_MODES_HW;
 }
 
-static bool both_lanes(const struct usb4_port *usb4)
+static bool both_lanes(const struct tb_margining *margining)
 {
-	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_2_LANES;
+	return margining->caps[0] & USB4_MARGIN_CAP_0_2_LANES;
 }
 
-static unsigned int independent_voltage_margins(const struct usb4_port *usb4)
+static unsigned int
+independent_voltage_margins(const struct tb_margining *margining)
 {
-	return (usb4->margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_INDP_MASK) >>
+	return (margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_INDP_MASK) >>
 		USB4_MARGIN_CAP_0_VOLTAGE_INDP_SHIFT;
 }
 
-static bool supports_time(const struct usb4_port *usb4)
+static bool supports_time(const struct tb_margining *margining)
 {
-	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_TIME;
+	return margining->caps[0] & USB4_MARGIN_CAP_0_TIME;
 }
 
 /* Only applicable if supports_time() returns true */
-static unsigned int independent_time_margins(const struct usb4_port *usb4)
+static unsigned int
+independent_time_margins(const struct tb_margining *margining)
 {
-	return (usb4->margining->caps[1] & USB4_MARGIN_CAP_1_TIME_INDP_MASK) >>
+	return (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_INDP_MASK) >>
 		USB4_MARGIN_CAP_1_TIME_INDP_SHIFT;
 }
 
@@ -448,9 +452,8 @@  margining_ber_level_write(struct file *file, const char __user *user_buf,
 			   size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	unsigned int val;
 	int ret = 0;
 	char *buf;
@@ -458,7 +461,7 @@  margining_ber_level_write(struct file *file, const char __user *user_buf,
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	if (usb4->margining->software) {
+	if (margining->software) {
 		ret = -EINVAL;
 		goto out_unlock;
 	}
@@ -475,13 +478,13 @@  margining_ber_level_write(struct file *file, const char __user *user_buf,
 	if (ret)
 		goto out_free;
 
-	if (val < usb4->margining->min_ber_level ||
-	    val > usb4->margining->max_ber_level) {
+	if (val < margining->min_ber_level ||
+	    val > margining->max_ber_level) {
 		ret = -EINVAL;
 		goto out_free;
 	}
 
-	usb4->margining->ber_level = val;
+	margining->ber_level = val;
 
 out_free:
 	free_page((unsigned long)buf);
@@ -501,52 +504,50 @@  static void ber_level_show(struct seq_file *s, unsigned int val)
 
 static int margining_ber_level_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
+	const struct tb_margining *margining = s->private;
 
-	if (usb4->margining->software)
+	if (margining->software)
 		return -EINVAL;
-	ber_level_show(s, usb4->margining->ber_level);
+	ber_level_show(s, margining->ber_level);
 	return 0;
 }
 DEBUGFS_ATTR_RW(margining_ber_level);
 
 static int margining_caps_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	u32 cap0, cap1;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
 	/* Dump the raw caps first */
-	cap0 = usb4->margining->caps[0];
+	cap0 = margining->caps[0];
 	seq_printf(s, "0x%08x\n", cap0);
-	cap1 = usb4->margining->caps[1];
+	cap1 = margining->caps[1];
 	seq_printf(s, "0x%08x\n", cap1);
 
 	seq_printf(s, "# software margining: %s\n",
-		   supports_software(usb4) ? "yes" : "no");
-	if (supports_hardware(usb4)) {
+		   supports_software(margining) ? "yes" : "no");
+	if (supports_hardware(margining)) {
 		seq_puts(s, "# hardware margining: yes\n");
 		seq_puts(s, "# minimum BER level contour: ");
-		ber_level_show(s, usb4->margining->min_ber_level);
+		ber_level_show(s, margining->min_ber_level);
 		seq_puts(s, "# maximum BER level contour: ");
-		ber_level_show(s, usb4->margining->max_ber_level);
+		ber_level_show(s, margining->max_ber_level);
 	} else {
 		seq_puts(s, "# hardware margining: no\n");
 	}
 
 	seq_printf(s, "# both lanes simultaneously: %s\n",
-		  both_lanes(usb4) ? "yes" : "no");
+		  both_lanes(margining) ? "yes" : "no");
 	seq_printf(s, "# voltage margin steps: %u\n",
-		   usb4->margining->voltage_steps);
+		   margining->voltage_steps);
 	seq_printf(s, "# maximum voltage offset: %u mV\n",
-		   usb4->margining->max_voltage_offset);
+		   margining->max_voltage_offset);
 
-	switch (independent_voltage_margins(usb4)) {
+	switch (independent_voltage_margins(margining)) {
 	case USB4_MARGIN_CAP_0_VOLTAGE_MIN:
 		seq_puts(s, "# returns minimum between high and low voltage margins\n");
 		break;
@@ -558,12 +559,12 @@  static int margining_caps_show(struct seq_file *s, void *not_used)
 		break;
 	}
 
-	if (supports_time(usb4)) {
+	if (supports_time(margining)) {
 		seq_puts(s, "# time margining: yes\n");
 		seq_printf(s, "# time margining is destructive: %s\n",
 			   cap1 & USB4_MARGIN_CAP_1_TIME_DESTR ? "yes" : "no");
 
-		switch (independent_time_margins(usb4)) {
+		switch (independent_time_margins(margining)) {
 		case USB4_MARGIN_CAP_1_TIME_MIN:
 			seq_puts(s, "# returns minimum between left and right time margins\n");
 			break;
@@ -576,9 +577,9 @@  static int margining_caps_show(struct seq_file *s, void *not_used)
 		}
 
 		seq_printf(s, "# time margin steps: %u\n",
-			   usb4->margining->time_steps);
+			   margining->time_steps);
 		seq_printf(s, "# maximum time offset: %u mUI\n",
-			   usb4->margining->max_time_offset);
+			   margining->max_time_offset);
 	} else {
 		seq_puts(s, "# time margining: no\n");
 	}
@@ -593,9 +594,8 @@  margining_lanes_write(struct file *file, const char __user *user_buf,
 		      size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	int ret = 0;
 	char *buf;
 
@@ -611,13 +611,13 @@  margining_lanes_write(struct file *file, const char __user *user_buf,
 	}
 
 	if (!strcmp(buf, "0")) {
-		usb4->margining->lanes = 0;
+		margining->lanes = 0;
 	} else if (!strcmp(buf, "1")) {
-		usb4->margining->lanes = 1;
+		margining->lanes = 1;
 	} else if (!strcmp(buf, "all")) {
 		/* Needs to be supported */
-		if (both_lanes(usb4))
-			usb4->margining->lanes = 7;
+		if (both_lanes(margining))
+			margining->lanes = 7;
 		else
 			ret = -EINVAL;
 	} else {
@@ -633,16 +633,15 @@  margining_lanes_write(struct file *file, const char __user *user_buf,
 
 static int margining_lanes_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	unsigned int lanes;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	lanes = usb4->margining->lanes;
-	if (both_lanes(usb4)) {
+	lanes = margining->lanes;
+	if (both_lanes(margining)) {
 		if (!lanes)
 			seq_puts(s, "[0] 1 all\n");
 		else if (lanes == 1)
@@ -666,9 +665,8 @@  static ssize_t margining_mode_write(struct file *file,
 				   size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	int ret = 0;
 	char *buf;
 
@@ -684,13 +682,13 @@  static ssize_t margining_mode_write(struct file *file,
 	}
 
 	if (!strcmp(buf, "software")) {
-		if (supports_software(usb4))
-			usb4->margining->software = true;
+		if (supports_software(margining))
+			margining->software = true;
 		else
 			ret = -EINVAL;
 	} else if (!strcmp(buf, "hardware")) {
-		if (supports_hardware(usb4))
-			usb4->margining->software = false;
+		if (supports_hardware(margining))
+			margining->software = false;
 		else
 			ret = -EINVAL;
 	} else {
@@ -706,23 +704,22 @@  static ssize_t margining_mode_write(struct file *file,
 
 static int margining_mode_show(struct seq_file *s, void *not_used)
 {
-	const struct tb_port *port = s->private;
-	const struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	const char *space = "";
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	if (supports_software(usb4)) {
-		if (usb4->margining->software)
+	if (supports_software(margining)) {
+		if (margining->software)
 			seq_puts(s, "[software]");
 		else
 			seq_puts(s, "software");
 		space = " ";
 	}
-	if (supports_hardware(usb4)) {
-		if (usb4->margining->software)
+	if (supports_hardware(margining)) {
+		if (margining->software)
 			seq_printf(s, "%shardware", space);
 		else
 			seq_printf(s, "%s[hardware]", space);
@@ -737,10 +734,9 @@  DEBUGFS_ATTR_RW(margining_mode);
 
 static int margining_run_write(void *data, u64 val)
 {
-	struct tb_port *port = data;
-	struct usb4_port *usb4 = port->usb4;
+	struct tb_margining *margining = data;
+	struct tb_port *port = margining->port;
 	struct tb_switch *sw = port->sw;
-	struct tb_margining *margining;
 	struct tb_switch *down_sw;
 	struct tb *tb = sw->tb;
 	int ret, clx;
@@ -775,8 +771,6 @@  static int margining_run_write(void *data, u64 val)
 		clx = ret;
 	}
 
-	margining = usb4->margining;
-
 	if (margining->software) {
 		tb_port_dbg(port, "running software %s lane margining for lanes %u\n",
 			    margining->time ? "time" : "voltage", margining->lanes);
@@ -817,16 +811,15 @@  static ssize_t margining_results_write(struct file *file,
 				       size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
 	/* Just clear the results */
-	usb4->margining->results[0] = 0;
-	usb4->margining->results[1] = 0;
+	margining->results[0] = 0;
+	margining->results[1] = 0;
 
 	mutex_unlock(&tb->lock);
 	return count;
@@ -860,15 +853,12 @@  static void time_margin_show(struct seq_file *s,
 
 static int margining_results_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb_margining *margining;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	margining = usb4->margining;
 	/* Dump the raw results first */
 	seq_printf(s, "0x%08x\n", margining->results[0]);
 	/* Only the hardware margining has two result dwords */
@@ -930,9 +920,8 @@  static ssize_t margining_test_write(struct file *file,
 				    size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	int ret = 0;
 	char *buf;
 
@@ -947,10 +936,10 @@  static ssize_t margining_test_write(struct file *file,
 		goto out_free;
 	}
 
-	if (!strcmp(buf, "time") && supports_time(usb4))
-		usb4->margining->time = true;
+	if (!strcmp(buf, "time") && supports_time(margining))
+		margining->time = true;
 	else if (!strcmp(buf, "voltage"))
-		usb4->margining->time = false;
+		margining->time = false;
 	else
 		ret = -EINVAL;
 
@@ -963,15 +952,14 @@  static ssize_t margining_test_write(struct file *file,
 
 static int margining_test_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	if (supports_time(usb4)) {
-		if (usb4->margining->time)
+	if (supports_time(margining)) {
+		if (margining->time)
 			seq_puts(s, "voltage [time]\n");
 		else
 			seq_puts(s, "[voltage] time\n");
@@ -989,9 +977,8 @@  static ssize_t margining_margin_write(struct file *file,
 				    size_t count, loff_t *ppos)
 {
 	struct seq_file *s = file->private_data;
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 	int ret = 0;
 	char *buf;
 
@@ -1006,18 +993,18 @@  static ssize_t margining_margin_write(struct file *file,
 		goto out_free;
 	}
 
-	if (usb4->margining->time) {
+	if (margining->time) {
 		if (!strcmp(buf, "left"))
-			usb4->margining->right_high = false;
+			margining->right_high = false;
 		else if (!strcmp(buf, "right"))
-			usb4->margining->right_high = true;
+			margining->right_high = true;
 		else
 			ret = -EINVAL;
 	} else {
 		if (!strcmp(buf, "low"))
-			usb4->margining->right_high = false;
+			margining->right_high = false;
 		else if (!strcmp(buf, "high"))
-			usb4->margining->right_high = true;
+			margining->right_high = true;
 		else
 			ret = -EINVAL;
 	}
@@ -1031,20 +1018,19 @@  static ssize_t margining_margin_write(struct file *file,
 
 static int margining_margin_show(struct seq_file *s, void *not_used)
 {
-	struct tb_port *port = s->private;
-	struct usb4_port *usb4 = port->usb4;
-	struct tb *tb = port->sw->tb;
+	struct tb_margining *margining = s->private;
+	struct tb *tb = margining->port->sw->tb;
 
 	if (mutex_lock_interruptible(&tb->lock))
 		return -ERESTARTSYS;
 
-	if (usb4->margining->time) {
-		if (usb4->margining->right_high)
+	if (margining->time) {
+		if (margining->right_high)
 			seq_puts(s, "left [right]\n");
 		else
 			seq_puts(s, "[left] right\n");
 	} else {
-		if (usb4->margining->right_high)
+		if (margining->right_high)
 			seq_puts(s, "low [high]\n");
 		else
 			seq_puts(s, "[low] high\n");
@@ -1075,16 +1061,16 @@  static void margining_port_init(struct tb_port *port)
 	if (!margining)
 		return;
 
+	margining->port = port;
+
 	ret = usb4_port_margining_caps(port, margining->caps);
 	if (ret) {
 		kfree(margining);
 		return;
 	}
 
-	usb4->margining = margining;
-
 	/* Set the initial mode */
-	if (supports_software(usb4))
+	if (supports_software(margining))
 		margining->software = true;
 
 	val = (margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_STEPS_MASK) >>
@@ -1094,7 +1080,7 @@  static void margining_port_init(struct tb_port *port)
 		USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_SHIFT;
 	margining->max_voltage_offset = 74 + val * 2;
 
-	if (supports_time(usb4)) {
+	if (supports_time(margining)) {
 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_STEPS_MASK) >>
 			USB4_MARGIN_CAP_1_TIME_STEPS_SHIFT;
 		margining->time_steps = val;
@@ -1108,7 +1094,7 @@  static void margining_port_init(struct tb_port *port)
 	}
 
 	dir = debugfs_create_dir("margining", parent);
-	if (supports_hardware(usb4)) {
+	if (supports_hardware(margining)) {
 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_MIN_BER_MASK) >>
 			USB4_MARGIN_CAP_1_MIN_BER_SHIFT;
 		margining->min_ber_level = val;
@@ -1119,19 +1105,23 @@  static void margining_port_init(struct tb_port *port)
 		/* Set the default to minimum */
 		margining->ber_level = margining->min_ber_level;
 
-		debugfs_create_file("ber_level_contour", 0400, dir, port,
+		debugfs_create_file("ber_level_contour", 0400, dir, margining,
 				    &margining_ber_level_fops);
 	}
-	debugfs_create_file("caps", 0400, dir, port, &margining_caps_fops);
-	debugfs_create_file("lanes", 0600, dir, port, &margining_lanes_fops);
-	debugfs_create_file("mode", 0600, dir, port, &margining_mode_fops);
-	debugfs_create_file("run", 0600, dir, port, &margining_run_fops);
-	debugfs_create_file("results", 0600, dir, port, &margining_results_fops);
-	debugfs_create_file("test", 0600, dir, port, &margining_test_fops);
-	if (independent_voltage_margins(usb4) == USB4_MARGIN_CAP_0_VOLTAGE_HL ||
-	    (supports_time(usb4) &&
-	     independent_time_margins(usb4) == USB4_MARGIN_CAP_1_TIME_LR))
-		debugfs_create_file("margin", 0600, dir, port, &margining_margin_fops);
+	debugfs_create_file("caps", 0400, dir, margining, &margining_caps_fops);
+	debugfs_create_file("lanes", 0600, dir, margining, &margining_lanes_fops);
+	debugfs_create_file("mode", 0600, dir, margining, &margining_mode_fops);
+	debugfs_create_file("run", 0600, dir, margining, &margining_run_fops);
+	debugfs_create_file("results", 0600, dir, margining,
+			    &margining_results_fops);
+	debugfs_create_file("test", 0600, dir, margining, &margining_test_fops);
+	if (independent_voltage_margins(margining) == USB4_MARGIN_CAP_0_VOLTAGE_HL ||
+	    (supports_time(margining) &&
+	     independent_time_margins(margining) == USB4_MARGIN_CAP_1_TIME_LR))
+		debugfs_create_file("margin", 0600, dir, margining,
+				    &margining_margin_fops);
+
+	usb4->margining = margining;
 }
 
 static void margining_port_remove(struct tb_port *port)