net: stmmac: Add support for external trigger timestamping

The Synopsis MAC controller supports auxiliary snapshot feature that
allows user to store a snapshot of the system time based on an external
event.

This patch add supports to the above mentioned feature. Users will be
able to triggered capturing the time snapshot from user-space using
application such as testptp or any other applications that uses the
PTP_EXTTS_REQUEST ioctl request.

Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Tan Tee Min <tee.min.tan@intel.com>
Co-developed-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 39 insertions, 0 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
index 113c51bcc0b5..074e2cdfb0fa 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
@@ -12,8 +12,11 @@
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/delay.h>
+#include <linux/ptp_clock_kernel.h>
 #include "common.h"
 #include "stmmac_ptp.h"
+#include "dwmac4.h"
+#include "stmmac.h"
 
 static void config_hw_tstamping(void __iomem *ioaddr, u32 data)
 {
@@ -163,6 +166,41 @@ static void get_ptptime(void __iomem *ptpaddr, u64 *ptp_time)
 	*ptp_time = ns;
 }
 
+static void timestamp_interrupt(struct stmmac_priv *priv)
+{
+	u32 num_snapshot, ts_status, tsync_int;
+	struct ptp_clock_event event;
+	unsigned long flags;
+	u64 ptp_time;
+	int i;
+
+	tsync_int = readl(priv->ioaddr + GMAC_INT_STATUS) & GMAC_INT_TSIE;
+
+	if (!tsync_int)
+		return;
+
+	/* Read timestamp status to clear interrupt from either external
+	 * timestamp or start/end of PPS.
+	 */
+	ts_status = readl(priv->ioaddr + GMAC_TIMESTAMP_STATUS);
+
+	if (!priv->plat->ext_snapshot_en)
+		return;
+
+	num_snapshot = (ts_status & GMAC_TIMESTAMP_ATSNS_MASK) >>
+		       GMAC_TIMESTAMP_ATSNS_SHIFT;
+
+	for (i = 0; i < num_snapshot; i++) {
+		spin_lock_irqsave(&priv->ptp_lock, flags);
+		get_ptptime(priv->ptpaddr, &ptp_time);
+		spin_unlock_irqrestore(&priv->ptp_lock, flags);
+		event.type = PTP_CLOCK_EXTTS;
+		event.index = 0;
+		event.timestamp = ptp_time;
+		ptp_clock_event(priv->ptp_clock, &event);
+	}
+}
+
 const struct stmmac_hwtimestamp stmmac_ptp = {
 	.config_hw_tstamping = config_hw_tstamping,
 	.init_systime = init_systime,
@@ -171,4 +209,5 @@ const struct stmmac_hwtimestamp stmmac_ptp = {
 	.adjust_systime = adjust_systime,
 	.get_systime = get_systime,
 	.get_ptptime = get_ptptime,
+	.timestamp_interrupt = timestamp_interrupt,
 };