ar71xx: fix ethernet MAC reset on DMA hang

Fully reset the chip like on a full up/down, but without the PHY
statemachine restart.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Backport of r48228

SVN-Revision: 48246

diff --git a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
index 9bb099c8a6b80f92622f8e859ab52c276a48ebf6..fbd6bef63d13c576bca6479c0a31eb37b3f6c019 100644 (file)
--- a/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
+++ b/target/linux/ar71xx/files/drivers/net/ethernet/atheros/ag71xx/ag71xx_main.c
@@ -538,7 +538,8 @@ static void ag71xx_hw_start(struct ag71xx *ag)
        netif_wake_queue(ag->dev);
 }
 
-void ag71xx_link_adjust(struct ag71xx *ag)
+static void
+__ag71xx_link_adjust(struct ag71xx *ag, bool update)
 {
        struct ag71xx_platform_data *pdata = ag71xx_get_pdata(ag);
        u32 cfg2;
@@ -546,7 +547,7 @@ void ag71xx_link_adjust(struct ag71xx *ag)
        u32 fifo5;
        u32 fifo3;
 
-       if (!ag->link) {
+       if (!ag->link && update) {
                ag71xx_hw_stop(ag);
                netif_carrier_off(ag->dev);
                if (netif_msg_link(ag))
@@ -598,7 +599,7 @@ void ag71xx_link_adjust(struct ag71xx *ag)
 
        ag71xx_wr(ag, AG71XX_REG_FIFO_CFG3, fifo3);
 
-       if (pdata->set_speed)
+       if (update && pdata->set_speed)
                pdata->set_speed(ag->speed);
 
        ag71xx_wr(ag, AG71XX_REG_MAC_CFG2, cfg2);
@@ -607,7 +608,7 @@ void ag71xx_link_adjust(struct ag71xx *ag)
        ag71xx_hw_start(ag);
 
        netif_carrier_on(ag->dev);
-       if (netif_msg_link(ag))
+       if (update && netif_msg_link(ag))
                pr_info("%s: link up (%sMbps/%s duplex)\n",
                        ag->dev->name,
                        ag71xx_speed_str(ag),
@@ -631,34 +632,66 @@ void ag71xx_link_adjust(struct ag71xx *ag)
                ag71xx_rr(ag, AG71XX_REG_MAC_IFCTL));
 }
 
+void ag71xx_link_adjust(struct ag71xx *ag)
+{
+       __ag71xx_link_adjust(ag, true);
+}
+
+static int ag71xx_hw_enable(struct ag71xx *ag)
+{
+       int ret;
+
+       ret = ag71xx_rings_init(ag);
+       if (ret)
+               return ret;
+
+       napi_enable(&ag->napi);
+       ag71xx_wr(ag, AG71XX_REG_TX_DESC, ag->tx_ring.descs_dma);
+       ag71xx_wr(ag, AG71XX_REG_RX_DESC, ag->rx_ring.descs_dma);
+       netif_start_queue(ag->dev);
+
+       return 0;
+}
+
+static void ag71xx_hw_disable(struct ag71xx *ag)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&ag->lock, flags);
+
+       netif_stop_queue(ag->dev);
+
+       ag71xx_hw_stop(ag);
+       ag71xx_dma_reset(ag);
+
+       napi_disable(&ag->napi);
+       del_timer_sync(&ag->oom_timer);
+
+       spin_unlock_irqrestore(&ag->lock, flags);
+
+       ag71xx_rings_cleanup(ag);
+}
+
 static int ag71xx_open(struct net_device *dev)
 {
        struct ag71xx *ag = netdev_priv(dev);
        unsigned int max_frame_len;
        int ret;
 
+       netif_carrier_off(dev);
        max_frame_len = ag71xx_max_frame_len(dev->mtu);
        ag->rx_buf_size = max_frame_len + NET_SKB_PAD + NET_IP_ALIGN;
 
        /* setup max frame length */
        ag71xx_wr(ag, AG71XX_REG_MAC_MFL, max_frame_len);
+       ag71xx_hw_set_macaddr(ag, dev->dev_addr);
 
-       ret = ag71xx_rings_init(ag);
+       ret = ag71xx_hw_enable(ag);
        if (ret)
                goto err;
 
-       napi_enable(&ag->napi);
-
-       netif_carrier_off(dev);
        ag71xx_phy_start(ag);
 
-       ag71xx_wr(ag, AG71XX_REG_TX_DESC, ag->tx_ring.descs_dma);
-       ag71xx_wr(ag, AG71XX_REG_RX_DESC, ag->rx_ring.descs_dma);
-
-       ag71xx_hw_set_macaddr(ag, dev->dev_addr);
-
-       netif_start_queue(dev);
-
        return 0;
 
 err:
@@ -669,24 +702,10 @@ err:
 static int ag71xx_stop(struct net_device *dev)
 {
        struct ag71xx *ag = netdev_priv(dev);
-       unsigned long flags;
 
        netif_carrier_off(dev);
        ag71xx_phy_stop(ag);
-
-       spin_lock_irqsave(&ag->lock, flags);
-
-       netif_stop_queue(dev);
-
-       ag71xx_hw_stop(ag);
-       ag71xx_dma_reset(ag);
-
-       napi_disable(&ag->napi);
-       del_timer_sync(&ag->oom_timer);
-
-       spin_unlock_irqrestore(&ag->lock, flags);
-
-       ag71xx_rings_cleanup(ag);
+       ag71xx_hw_disable(ag);
 
        return 0;
 }
@@ -870,14 +889,12 @@ static void ag71xx_restart_work_func(struct work_struct *work)
 {
        struct ag71xx *ag = container_of(work, struct ag71xx, restart_work);
 
-       if (ag71xx_get_pdata(ag)->is_ar724x) {
-               ag->link = 0;
-               ag71xx_link_adjust(ag);
-               return;
-       }
-
-       ag71xx_stop(ag->dev);
-       ag71xx_open(ag->dev);
+       rtnl_lock();
+       ag71xx_hw_disable(ag);
+       ag71xx_hw_enable(ag);
+       if (ag->link)
+               __ag71xx_link_adjust(ag, false);
+       rtnl_unlock();
 }
 
 static bool ag71xx_check_dma_stuck(struct ag71xx *ag, unsigned long timestamp)