[PATCH net-next v3 3/4] net: macb: Add ARP support to WOL

[Vineeth Karumanchi <vineeth.karumanchi@amd.com>]

Extend wake-on LAN support with an ARP packet.

Advertise wake-on LAN supported modes by default without relying on
dt node. By default, wake-on LAN will be in disabled state.
Using ethtool users can enable/disable or choose packet types.

For wake-on LAN via ARP, ensure the IP address is assigned and
report an error otherwise.

Co-developed-by: Harini Katakam <harini.katakam@amd.com>
Signed-off-by: Harini Katakam <harini.katakam@amd.com>
Signed-off-by: Vineeth Karumanchi <vineeth.karumanchi@amd.com>
---
 drivers/net/ethernet/cadence/macb.h      |  1 +
 drivers/net/ethernet/cadence/macb_main.c | 50 +++++++++++++++---------
 2 files changed, 32 insertions(+), 19 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 50cd35ef21ad..122663ff7834 100644
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -1306,6 +1306,7 @@ struct macb {
 	unsigned int		jumbo_max_len;
 
 	u32			wol;
+	u32			wolopts;
 
 	/* holds value of rx watermark value for pbuf_rxcutthru register */
 	u32			rx_watermark;
diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 4007b291526f..7eabd9c01f23 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -38,6 +38,7 @@
 #include <linux/ptp_classify.h>
 #include <linux/reset.h>
 #include <linux/firmware/xlnx-zynqmp.h>
+#include <linux/inetdevice.h>
 #include "macb.h"
 
 /* This structure is only used for MACB on SiFive FU540 devices */
@@ -84,8 +85,9 @@ struct sifive_fu540_macb_mgmt {
 #define GEM_MTU_MIN_SIZE	ETH_MIN_MTU
 #define MACB_NETIF_LSO		NETIF_F_TSO
 
-#define MACB_WOL_HAS_MAGIC_PACKET	(0x1 << 0)
-#define MACB_WOL_ENABLED		(0x1 << 1)
+#define MACB_WOL_ENABLED		(0x1 << 0)
+#define MACB_WOL_HAS_MAGIC_PACKET	(0x1 << 1)
+#define MACB_WOL_HAS_ARP_PACKET		(0x1 << 2)
 
 #define HS_SPEED_10000M			4
 #define MACB_SERDES_RATE_10G		1
@@ -3278,13 +3280,11 @@ static void macb_get_wol(struct net_device *netdev, struct ethtool_wolinfo *wol)
 {
 	struct macb *bp = netdev_priv(netdev);
 
-	if (bp->wol & MACB_WOL_HAS_MAGIC_PACKET) {
-		phylink_ethtool_get_wol(bp->phylink, wol);
-		wol->supported |= WAKE_MAGIC;
-
-		if (bp->wol & MACB_WOL_ENABLED)
-			wol->wolopts |= WAKE_MAGIC;
-	}
+	phylink_ethtool_get_wol(bp->phylink, wol);
+	wol->supported |= (bp->wol & MACB_WOL_HAS_MAGIC_PACKET) ? WAKE_MAGIC : 0;
+	wol->supported |= (bp->wol & MACB_WOL_HAS_ARP_PACKET) ? WAKE_ARP : 0;
+	/* Pass wolopts to ethtool */
+	wol->wolopts = bp->wolopts;
 }
 
 static int macb_set_wol(struct net_device *netdev, struct ethtool_wolinfo *wol)
@@ -3300,11 +3300,10 @@ static int macb_set_wol(struct net_device *netdev, struct ethtool_wolinfo *wol)
 	if (!ret || ret != -EOPNOTSUPP)
 		return ret;
 
-	if (!(bp->wol & MACB_WOL_HAS_MAGIC_PACKET) ||
-	    (wol->wolopts & ~WAKE_MAGIC))
-		return -EOPNOTSUPP;
+	bp->wolopts = (wol->wolopts & WAKE_MAGIC) ? WAKE_MAGIC : 0;
+	bp->wolopts |= (wol->wolopts & WAKE_ARP) ? WAKE_ARP : 0;
 
-	if (wol->wolopts & WAKE_MAGIC)
+	if (bp->wolopts)
 		bp->wol |= MACB_WOL_ENABLED;
 	else
 		bp->wol &= ~MACB_WOL_ENABLED;
@@ -5085,10 +5084,8 @@ static int macb_probe(struct platform_device *pdev)
 	else
 		bp->max_tx_length = GEM_MAX_TX_LEN;
 
-	bp->wol = 0;
-	if (of_property_read_bool(np, "magic-packet"))
-		bp->wol |= MACB_WOL_HAS_MAGIC_PACKET;
-	device_set_wakeup_capable(&pdev->dev, bp->wol & MACB_WOL_HAS_MAGIC_PACKET);
+	bp->wol = (MACB_WOL_HAS_ARP_PACKET | MACB_WOL_HAS_MAGIC_PACKET);
+	device_set_wakeup_capable(&pdev->dev, 1);
 
 	bp->usrio = macb_config->usrio;
 
@@ -5245,6 +5242,7 @@ static int __maybe_unused macb_suspend(struct device *dev)
 	struct net_device *netdev = dev_get_drvdata(dev);
 	struct macb *bp = netdev_priv(netdev);
 	struct macb_queue *queue;
+	struct in_ifaddr *ifa;
 	unsigned long flags;
 	unsigned int q;
 	int err;
@@ -5257,6 +5255,12 @@ static int __maybe_unused macb_suspend(struct device *dev)
 		return 0;
 
 	if (bp->wol & MACB_WOL_ENABLED) {
+		/* Check for IP address in WOL ARP mode */
+		ifa = rcu_dereference(__in_dev_get_rcu(bp->dev)->ifa_list);
+		if ((bp->wolopts & WAKE_ARP) && !ifa) {
+			netdev_err(netdev, "IP address not assigned\n");
+			return -EOPNOTSUPP;
+		}
 		spin_lock_irqsave(&bp->lock, flags);
 
 		/* Disable Tx and Rx engines before  disabling the queues,
@@ -5290,6 +5294,14 @@ static int __maybe_unused macb_suspend(struct device *dev)
 		macb_writel(bp, TSR, -1);
 		macb_writel(bp, RSR, -1);
 
+		tmp = (bp->wolopts & WAKE_MAGIC) ? MACB_BIT(MAG) : 0;
+		if (bp->wolopts & WAKE_ARP) {
+			tmp |= MACB_BIT(ARP);
+			/* write IP address into register */
+			tmp |= MACB_BFEXT(IP,
+					 (__force u32)(cpu_to_be32p((uint32_t *)&ifa->ifa_local)));
+		}
+
 		/* Change interrupt handler and
 		 * Enable WoL IRQ on queue 0
 		 */
@@ -5305,7 +5317,7 @@ static int __maybe_unused macb_suspend(struct device *dev)
 				return err;
 			}
 			queue_writel(bp->queues, IER, GEM_BIT(WOL));
-			gem_writel(bp, WOL, MACB_BIT(MAG));
+			gem_writel(bp, WOL, tmp);
 		} else {
 			err = devm_request_irq(dev, bp->queues[0].irq, macb_wol_interrupt,
 					       IRQF_SHARED, netdev->name, bp->queues);
@@ -5317,7 +5329,7 @@ static int __maybe_unused macb_suspend(struct device *dev)
 				return err;
 			}
 			queue_writel(bp->queues, IER, MACB_BIT(WOL));
-			macb_writel(bp, WOL, MACB_BIT(MAG));
+			macb_writel(bp, WOL, tmp);
 		}
 		spin_unlock_irqrestore(&bp->lock, flags);
 
-- 
2.34.1