ucc_geth: Fix TX watchdog timeout handling

The timeout handling code is currently broken in several ways:

- It calls stop() (which frees all the memory and IRQ), and then
  calls startup() (which won't re-request IRQ, neither it will
  re-init the Fast UCC structure).
- It calls these routines from the softirq context, which is wrong,
  since stop() calls free_irq() (which might sleep) and startup()
  allocates things with GFP_KERNEL.
- It won't soft-reset the PHY. We need the PHY reset for at least
  MPC8360E-MDS boards with Marvell 88E1111 PHY, the PHY won't recover
  from timeouts w/o the reset.

So the patch fixes these problems by implementing the workqueue for the
timeout handling, and there we fully re-open the device via close() and
open() calls. The close/open paths do the right things, and I can see
that the driver actually survive the timeouts.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ucc_geth.c b/drivers/net/ucc_geth.c
index fa25dc1fcdf1bab31b1c89cae9bede38efe53a9d..6ebefe951b951162603627c4ca4ee6de385e4fd1 100644 (file)
--- a/drivers/net/ucc_geth.c
+++ b/drivers/net/ucc_geth.c
@@ -3355,13 +3355,17 @@ static int ucc_geth_startup(struct ucc_geth_private *ugeth)
        return 0;
 }
 
-/* ucc_geth_timeout gets called when a packet has not been
- * transmitted after a set amount of time.
- * For now, assume that clearing out all the structures, and
- * starting over will fix the problem. */
-static void ucc_geth_timeout(struct net_device *dev)
+static int ucc_geth_close(struct net_device *dev);
+static int ucc_geth_open(struct net_device *dev);
+
+/* Reopen device. This will reset the MAC and PHY. */
+static void ucc_geth_timeout_work(struct work_struct *work)
 {
-       struct ucc_geth_private *ugeth = netdev_priv(dev);
+       struct ucc_geth_private *ugeth;
+       struct net_device *dev;
+
+       ugeth = container_of(work, struct ucc_geth_private, timeout_work);
+       dev = ugeth->dev;
 
        ugeth_vdbg("%s: IN", __func__);
 
@@ -3370,13 +3374,29 @@ static void ucc_geth_timeout(struct net_device *dev)
        ugeth_dump_regs(ugeth);
 
        if (dev->flags & IFF_UP) {
-               ucc_geth_stop(ugeth);
-               ucc_geth_startup(ugeth);
+               /*
+                * Must reset MAC *and* PHY. This is done by reopening
+                * the device.
+                */
+               ucc_geth_close(dev);
+               ucc_geth_open(dev);
        }
 
        netif_tx_schedule_all(dev);
 }
 
+/*
+ * ucc_geth_timeout gets called when a packet has not been
+ * transmitted after a set amount of time.
+ */
+static void ucc_geth_timeout(struct net_device *dev)
+{
+       struct ucc_geth_private *ugeth = netdev_priv(dev);
+
+       netif_carrier_off(dev);
+       schedule_work(&ugeth->timeout_work);
+}
+
 /* This is called by the kernel when a frame is ready for transmission. */
 /* It is pointed to by the dev->hard_start_xmit function pointer */
 static int ucc_geth_start_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -4027,6 +4047,7 @@ static int ucc_geth_probe(struct of_device* ofdev, const struct of_device_id *ma
        dev->hard_start_xmit = ucc_geth_start_xmit;
        dev->tx_timeout = ucc_geth_timeout;
        dev->watchdog_timeo = TX_TIMEOUT;
+       INIT_WORK(&ugeth->timeout_work, ucc_geth_timeout_work);
        netif_napi_add(dev, &ugeth->napi, ucc_geth_poll, UCC_GETH_DEV_WEIGHT);
 #ifdef CONFIG_NET_POLL_CONTROLLER
        dev->poll_controller = ucc_netpoll;

diff --git a/drivers/net/ucc_geth.h b/drivers/net/ucc_geth.h
index abc0e224263487efb7a28ab7a07f4d40bdce9d87..d74d2f7cb73968e8e98e3a7f1ef65f8ddb20c794 100644 (file)
--- a/drivers/net/ucc_geth.h
+++ b/drivers/net/ucc_geth.h
@@ -1186,6 +1186,7 @@ struct ucc_geth_private {
        struct ucc_fast_private *uccf;
        struct net_device *dev;
        struct napi_struct napi;
+       struct work_struct timeout_work;
        struct ucc_geth __iomem *ug_regs;
        struct ucc_geth_init_pram *p_init_enet_param_shadow;
        struct ucc_geth_exf_global_pram __iomem *p_exf_glbl_param;