[PATCH net-next 10/15] net: lan969x: add PTP handler function

[Daniel Machon <daniel.machon@microchip.com>]

Add PTP IRQ handler for lan969x. This is required, as the PTP registers
are placed in two different targets on Sparx5 and lan969x. The
implementation is otherwise the same as on Sparx5.

Also, expose sparx5_get_hwtimestamp() for use by lan969x.

Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
---
 drivers/net/ethernet/microchip/lan969x/lan969x.c   | 90 ++++++++++++++++++++++
 .../net/ethernet/microchip/sparx5/sparx5_main.h    |  5 ++
 drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c |  7 +-
 3 files changed, 99 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan969x/lan969x.c b/drivers/net/ethernet/microchip/lan969x/lan969x.c
index c92f04647f12..692b81e829ef 100644
--- a/drivers/net/ethernet/microchip/lan969x/lan969x.c
+++ b/drivers/net/ethernet/microchip/lan969x/lan969x.c
@@ -201,6 +201,95 @@ static int lan969x_port_mux_set(struct sparx5 *sparx5, struct sparx5_port *port,
 	return 0;
 }
 
+static irqreturn_t lan969x_ptp_irq_handler(int irq, void *args)
+{
+	int budget = SPARX5_MAX_PTP_ID;
+	struct sparx5 *sparx5 = args;
+
+	while (budget--) {
+		struct sk_buff *skb, *skb_tmp, *skb_match = NULL;
+		struct skb_shared_hwtstamps shhwtstamps;
+		struct sparx5_port *port;
+		struct timespec64 ts;
+		unsigned long flags;
+		u32 val, id, txport;
+		u32 delay;
+
+		val = spx5_rd(sparx5, PTP_PTP_TWOSTEP_CTRL);
+
+		/* Check if a timestamp can be retrieved */
+		if (!(val & PTP_PTP_TWOSTEP_CTRL_PTP_VLD))
+			break;
+
+		WARN_ON(val & PTP_PTP_TWOSTEP_CTRL_PTP_OVFL);
+
+		if (!(val & PTP_PTP_TWOSTEP_CTRL_STAMP_TX))
+			continue;
+
+		/* Retrieve the ts Tx port */
+		txport = PTP_PTP_TWOSTEP_CTRL_STAMP_PORT_GET(val);
+
+		/* Retrieve its associated skb */
+		port = sparx5->ports[txport];
+
+		/* Retrieve the delay */
+		delay = spx5_rd(sparx5, PTP_PTP_TWOSTEP_STAMP_NSEC);
+		delay = PTP_PTP_TWOSTEP_STAMP_NSEC_STAMP_NSEC_GET(delay);
+
+		/* Get next timestamp from fifo, which needs to be the
+		 * rx timestamp which represents the id of the frame
+		 */
+		spx5_rmw(PTP_PTP_TWOSTEP_CTRL_PTP_NXT_SET(1),
+			 PTP_PTP_TWOSTEP_CTRL_PTP_NXT,
+			 sparx5, PTP_PTP_TWOSTEP_CTRL);
+
+		val = spx5_rd(sparx5, PTP_PTP_TWOSTEP_CTRL);
+
+		/* Check if a timestamp can be retrieved */
+		if (!(val & PTP_PTP_TWOSTEP_CTRL_PTP_VLD))
+			break;
+
+		/* Read RX timestamping to get the ID */
+		id = spx5_rd(sparx5, PTP_PTP_TWOSTEP_STAMP_NSEC);
+		id <<= 8;
+		id |= spx5_rd(sparx5, PTP_PTP_TWOSTEP_STAMP_SUBNS);
+
+		spin_lock_irqsave(&port->tx_skbs.lock, flags);
+		skb_queue_walk_safe(&port->tx_skbs, skb, skb_tmp) {
+			if (SPARX5_SKB_CB(skb)->ts_id != id)
+				continue;
+
+			__skb_unlink(skb, &port->tx_skbs);
+			skb_match = skb;
+			break;
+		}
+		spin_unlock_irqrestore(&port->tx_skbs.lock, flags);
+
+		/* Next ts */
+		spx5_rmw(PTP_PTP_TWOSTEP_CTRL_PTP_NXT_SET(1),
+			 PTP_PTP_TWOSTEP_CTRL_PTP_NXT,
+			 sparx5, PTP_PTP_TWOSTEP_CTRL);
+
+		if (WARN_ON(!skb_match))
+			continue;
+
+		spin_lock(&sparx5->ptp_ts_id_lock);
+		sparx5->ptp_skbs--;
+		spin_unlock(&sparx5->ptp_ts_id_lock);
+
+		/* Get the h/w timestamp */
+		sparx5_get_hwtimestamp(sparx5, &ts, delay);
+
+		/* Set the timestamp in the skb */
+		shhwtstamps.hwtstamp = ktime_set(ts.tv_sec, ts.tv_nsec);
+		skb_tstamp_tx(skb_match, &shhwtstamps);
+
+		dev_kfree_skb_any(skb_match);
+	}
+
+	return IRQ_HANDLED;
+}
+
 static const struct sparx5_regs lan969x_regs = {
 	.tsize = lan969x_tsize,
 	.gaddr = lan969x_gaddr,
@@ -242,6 +331,7 @@ static const struct sparx5_ops lan969x_ops = {
 	.get_hsch_max_group_rate = &lan969x_get_hsch_max_group_rate,
 	.get_sdlb_group          = &lan969x_get_sdlb_group,
 	.set_port_mux            = &lan969x_port_mux_set,
+	.ptp_irq_handler         = &lan969x_ptp_irq_handler,
 };
 
 const struct sparx5_match_data lan969x_desc = {
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
index 15f5d38776c4..3f66045c57ef 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
@@ -114,6 +114,8 @@ enum sparx5_vlan_port_type {
 #define SPX5_DSM_CAL_LEN               64
 #define SPX5_DSM_CAL_MAX_DEVS_PER_TAXI 13
 
+#define SPARX5_MAX_PTP_ID	512
+
 struct sparx5;
 
 struct sparx5_calendar_data {
@@ -499,6 +501,9 @@ void sparx5_ptp_txtstamp_release(struct sparx5_port *port,
 				 struct sk_buff *skb);
 irqreturn_t sparx5_ptp_irq_handler(int irq, void *args);
 int sparx5_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts);
+void sparx5_get_hwtimestamp(struct sparx5 *sparx5,
+			    struct timespec64 *ts,
+			    u32 nsec);
 
 /* sparx5_vcap_impl.c */
 int sparx5_vcap_init(struct sparx5 *sparx5);
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c b/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c
index a511f14312f1..9568e21e1c0e 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c
@@ -275,9 +275,9 @@ void sparx5_ptp_txtstamp_release(struct sparx5_port *port,
 	spin_unlock_irqrestore(&sparx5->ptp_ts_id_lock, flags);
 }
 
-static void sparx5_get_hwtimestamp(struct sparx5 *sparx5,
-				   struct timespec64 *ts,
-				   u32 nsec)
+void sparx5_get_hwtimestamp(struct sparx5 *sparx5,
+			    struct timespec64 *ts,
+			    u32 nsec)
 {
 	/* Read current PTP time to get seconds */
 	const struct sparx5_consts *consts = sparx5->data->consts;
@@ -305,6 +305,7 @@ static void sparx5_get_hwtimestamp(struct sparx5 *sparx5,
 
 	spin_unlock_irqrestore(&sparx5->ptp_clock_lock, flags);
 }
+EXPORT_SYMBOL_GPL(sparx5_get_hwtimestamp);
 
 irqreturn_t sparx5_ptp_irq_handler(int irq, void *args)
 {

-- 
2.34.1