ptp: ocp: add TOD debug information

TOD information is currently displayed only on module load,
which doesn't provide updated information as the system runs.

Create a debug file which provides the current TOD status information,
and move the information display there.
Signed-off-by: Vadim Fedorenko <vadfed@fb.com>
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ptp/ptp_ocp.c

@@ -88,9 +88,10 @@ struct tod_reg {
 #define TOD_CTRL_GNSS_MASK	((1U << 4) - 1)
 #define TOD_CTRL_GNSS_SHIFT	24
 
-#define TOD_STATUS_UTC_MASK	0xff
-#define TOD_STATUS_UTC_VALID	BIT(8)
-#define TOD_STATUS_LEAP_VALID	BIT(16)
+#define TOD_STATUS_UTC_MASK		0xff
+#define TOD_STATUS_UTC_VALID		BIT(8)
+#define TOD_STATUS_LEAP_ANNOUNCE	BIT(12)
+#define TOD_STATUS_LEAP_VALID		BIT(16)
 
 struct ts_reg {
 	u32	enable;
@@ -862,45 +863,26 @@ ptp_ocp_tod_init(struct ptp_ocp *bp)
 		ptp_ocp_utc_distribute(bp, reg & TOD_STATUS_UTC_MASK);
 }
 
-static void
-ptp_ocp_tod_info(struct ptp_ocp *bp)
+static const char *
+ptp_ocp_tod_proto_name(const int idx)
 {
 	static const char * const proto_name[] = {
 		"NMEA", "NMEA_ZDA", "NMEA_RMC", "NMEA_none",
 		"UBX", "UBX_UTC", "UBX_LS", "UBX_none"
 	};
+	return proto_name[idx];
+}
+
+static const char *
+ptp_ocp_tod_gnss_name(int idx)
+{
 	static const char * const gnss_name[] = {
 		"ALL", "COMBINED", "GPS", "GLONASS", "GALILEO", "BEIDOU",
+		"Unknown"
 	};
-	u32 version, ctrl, reg;
-	int idx;
-
-	version = ioread32(&bp->tod->version);
-	dev_info(&bp->pdev->dev, "TOD Version %d.%d.%d\n",
-		 version >> 24, (version >> 16) & 0xff, version & 0xffff);
-
-	ctrl = ioread32(&bp->tod->ctrl);
-	idx = ctrl & TOD_CTRL_PROTOCOL ? 4 : 0;
-	idx += (ctrl >> 16) & 3;
-	dev_info(&bp->pdev->dev, "control: %x\n", ctrl);
-	dev_info(&bp->pdev->dev, "TOD Protocol %s %s\n", proto_name[idx],
-		 ctrl & TOD_CTRL_ENABLE ? "enabled" : "");
-
-	idx = (ctrl >> TOD_CTRL_GNSS_SHIFT) & TOD_CTRL_GNSS_MASK;
-	if (idx < ARRAY_SIZE(gnss_name))
-		dev_info(&bp->pdev->dev, "GNSS %s\n", gnss_name[idx]);
-
-	reg = ioread32(&bp->tod->status);
-	dev_info(&bp->pdev->dev, "status: %x\n", reg);
-
-	reg = ioread32(&bp->tod->adj_sec);
-	dev_info(&bp->pdev->dev, "correction: %d\n", reg);
-
-	reg = ioread32(&bp->tod->utc_status);
-	dev_info(&bp->pdev->dev, "utc_status: %x\n", reg);
-	dev_info(&bp->pdev->dev, "utc_offset: %d  valid:%d  leap_valid:%d\n",
-		 reg & TOD_STATUS_UTC_MASK, reg & TOD_STATUS_UTC_VALID ? 1 : 0,
-		 reg & TOD_STATUS_LEAP_VALID ? 1 : 0);
+	if (idx > ARRAY_SIZE(gnss_name))
+		idx = ARRAY_SIZE(gnss_name) - 1;
+	return gnss_name[idx];
 }
 
 static int
@@ -2179,6 +2161,57 @@ ptp_ocp_summary_show(struct seq_file *s, void *data)
 }
 DEFINE_SHOW_ATTRIBUTE(ptp_ocp_summary);
 
+static int
+ptp_ocp_tod_status_show(struct seq_file *s, void *data)
+{
+	struct device *dev = s->private;
+	struct ptp_ocp *bp;
+	u32 val;
+	int idx;
+
+	bp = dev_get_drvdata(dev);
+
+	val = ioread32(&bp->tod->ctrl);
+	if (!(val & TOD_CTRL_ENABLE)) {
+		seq_printf(s, "TOD Slave disabled\n");
+		return 0;
+	}
+	seq_printf(s, "TOD Slave enabled, Control Register 0x%08X\n", val);
+
+	idx = val & TOD_CTRL_PROTOCOL ? 4 : 0;
+	idx += (val >> 16) & 3;
+	seq_printf(s, "Protocol %s\n", ptp_ocp_tod_proto_name(idx));
+
+	idx = (val >> TOD_CTRL_GNSS_SHIFT) & TOD_CTRL_GNSS_MASK;
+	seq_printf(s, "GNSS %s\n", ptp_ocp_tod_gnss_name(idx));
+
+	val = ioread32(&bp->tod->version);
+	seq_printf(s, "TOD Version %d.%d.%d\n",
+		val >> 24, (val >> 16) & 0xff, val & 0xffff);
+
+	val = ioread32(&bp->tod->status);
+	seq_printf(s, "Status register: 0x%08X\n", val);
+
+	val = ioread32(&bp->tod->adj_sec);
+	idx = (val & ~INT_MAX) ? -1 : 1;
+	idx *= (val & INT_MAX);
+	seq_printf(s, "Correction seconds: %d\n", idx);
+
+	val = ioread32(&bp->tod->utc_status);
+	seq_printf(s, "UTC status register: 0x%08X\n", val);
+	seq_printf(s, "UTC offset: %d  valid:%d\n",
+		val & TOD_STATUS_UTC_MASK, val & TOD_STATUS_UTC_VALID ? 1 : 0);
+	seq_printf(s, "Leap second info valid:%d, Leap second announce %d\n",
+		val & TOD_STATUS_LEAP_VALID ? 1 : 0,
+		val & TOD_STATUS_LEAP_ANNOUNCE ? 1 : 0);
+
+	val = ioread32(&bp->tod->leap);
+	seq_printf(s, "Time to next leap second (in sec): %d\n", (s32) val);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(ptp_ocp_tod_status);
+
 static struct dentry *ptp_ocp_debugfs_root;
 
 static void
@@ -2190,6 +2223,9 @@ ptp_ocp_debugfs_add_device(struct ptp_ocp *bp)
 	bp->debug_root = d;
 	debugfs_create_file("summary", 0444, bp->debug_root,
 			    &bp->dev, &ptp_ocp_summary_fops);
+	if (bp->tod)
+		debugfs_create_file("tod_status", 0444, bp->debug_root,
+				    &bp->dev, &ptp_ocp_tod_status_fops);
 }
 
 static void
@@ -2368,8 +2404,6 @@ ptp_ocp_info(struct ptp_ocp *bp)
 	u32 reg;
 
 	ptp_ocp_phc_info(bp);
-	if (bp->tod)
-		ptp_ocp_tod_info(bp);
 
 	if (bp->image) {
 		u32 ver = ioread32(&bp->image->version);