1 files changed, 18 insertions, 2 deletions

diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c
index 06c9f4100cb9..6ad44be08b33 100644
--- a/drivers/net/ethernet/moxa/moxart_ether.c
+++ b/drivers/net/ethernet/moxa/moxart_ether.c
@@ -25,6 +25,7 @@
 #include <linux/of_irq.h>
 #include <linux/crc32.h>
 #include <linux/crc32c.h>
+#include <linux/circ_buf.h>
 
 #include "moxart_ether.h"
 
@@ -278,6 +279,13 @@ rx_next:
         return rx;
 }
 
+static int moxart_tx_queue_space(struct net_device *ndev)
+{
+        struct moxart_mac_priv_t *priv = netdev_priv(ndev);
+
+        return CIRC_SPACE(priv->tx_head, priv->tx_tail, TX_DESC_NUM);
+}
+
 static void moxart_tx_finished(struct net_device *ndev)
 {
         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
@@ -297,6 +305,9 @@ static void moxart_tx_finished(struct net_device *ndev)
                 tx_tail = TX_NEXT(tx_tail);
         }
         priv->tx_tail = tx_tail;
+        if (netif_queue_stopped(ndev) &&
+            moxart_tx_queue_space(ndev) >= TX_WAKE_THRESHOLD)
+                netif_wake_queue(ndev);
 }
 
 static irqreturn_t moxart_mac_interrupt(int irq, void *dev_id)
@@ -324,13 +335,18 @@ static int moxart_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
         struct moxart_mac_priv_t *priv = netdev_priv(ndev);
         void *desc;
         unsigned int len;
-        unsigned int tx_head = priv->tx_head;
+        unsigned int tx_head;
         u32 txdes1;
         int ret = NETDEV_TX_BUSY;
 
+        spin_lock_irq(&priv->txlock);
+
+        tx_head = priv->tx_head;
         desc = priv->tx_desc_base + (TX_REG_DESC_SIZE * tx_head);
 
-        spin_lock_irq(&priv->txlock);
+        if (moxart_tx_queue_space(ndev) == 1)
+                netif_stop_queue(ndev);
+
         if (moxart_desc_read(desc + TX_REG_OFFSET_DESC0) & TX_DESC0_DMA_OWN) {
                 net_dbg_ratelimited("no TX space for packet\n");
                 priv->stats.tx_dropped++;