m68knommu: fix FEC driver locking

It's easy: grab locks before talking to hardware and realease
them afterwards. The one big lock has been splitted into a hw_lock
and mii_lock.

Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/net/fec.c b/drivers/net/fec.c
index 5f9c2c1..32a4f17 100644 (file)
--- a/drivers/net/fec.c
+++ b/drivers/net/fec.c
@@ -209,7 +209,10 @@ struct fec_enet_private {
        cbd_t   *cur_rx, *cur_tx;               /* The next free ring entry */
        cbd_t   *dirty_tx;      /* The ring entries to be free()ed. */
        uint    tx_full;
-       spinlock_t lock;
+       /* hold while accessing the HW like ringbuffer for tx/rx but not MAC */
+       spinlock_t hw_lock;
+       /* hold while accessing the mii_list_t() elements */
+       spinlock_t mii_lock;
 
        uint    phy_id;
        uint    phy_id_done;
@@ -313,6 +316,7 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
        volatile fec_t  *fecp;
        volatile cbd_t  *bdp;
        unsigned short  status;
+       unsigned long flags;
 
        fep = netdev_priv(dev);
        fecp = (volatile fec_t*)dev->base_addr;
@@ -322,6 +326,7 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
                return 1;
        }
 
+       spin_lock_irqsave(&fep->hw_lock, flags);
        /* Fill in a Tx ring entry */
        bdp = fep->cur_tx;
 
@@ -332,6 +337,7 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 * This should not happen, since dev->tbusy should be set.
                 */
                printk("%s: tx queue full!.\n", dev->name);
+               spin_unlock_irqrestore(&fep->hw_lock, flags);
                return 1;
        }
 #endif
@@ -370,8 +376,6 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
        flush_dcache_range((unsigned long)skb->data,
                           (unsigned long)skb->data + skb->len);
 
-       spin_lock_irq(&fep->lock);
-
        /* Send it on its way.  Tell FEC it's ready, interrupt when done,
         * it's the last BD of the frame, and to put the CRC on the end.
         */
@@ -400,7 +404,7 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
        fep->cur_tx = (cbd_t *)bdp;
 
-       spin_unlock_irq(&fep->lock);
+       spin_unlock_irqrestore(&fep->hw_lock, flags);
 
        return 0;
 }
@@ -458,19 +462,20 @@ fec_enet_interrupt(int irq, void * dev_id)
        struct  net_device *dev = dev_id;
        volatile fec_t  *fecp;
        uint    int_events;
-       int handled = 0;
+       irqreturn_t ret = IRQ_NONE;
 
        fecp = (volatile fec_t*)dev->base_addr;
 
        /* Get the interrupt events that caused us to be here.
        */
-       while ((int_events = fecp->fec_ievent) != 0) {
+       do {
+               int_events = fecp->fec_ievent;
                fecp->fec_ievent = int_events;
 
                /* Handle receive event in its own function.
                 */
                if (int_events & FEC_ENET_RXF) {
-                       handled = 1;
+                       ret = IRQ_HANDLED;
                        fec_enet_rx(dev);
                }
 
@@ -479,17 +484,18 @@ fec_enet_interrupt(int irq, void * dev_id)
                   them as part of the transmit process.
                */
                if (int_events & FEC_ENET_TXF) {
-                       handled = 1;
+                       ret = IRQ_HANDLED;
                        fec_enet_tx(dev);
                }
 
                if (int_events & FEC_ENET_MII) {
-                       handled = 1;
+                       ret = IRQ_HANDLED;
                        fec_enet_mii(dev);
                }
 
-       }
-       return IRQ_RETVAL(handled);
+       } while (int_events);
+
+       return ret;
 }
 
 
@@ -502,7 +508,7 @@ fec_enet_tx(struct net_device *dev)
        struct  sk_buff *skb;
 
        fep = netdev_priv(dev);
-       spin_lock(&fep->lock);
+       spin_lock_irq(&fep->hw_lock);
        bdp = fep->dirty_tx;
 
        while (((status = bdp->cbd_sc) & BD_ENET_TX_READY) == 0) {
@@ -561,7 +567,7 @@ fec_enet_tx(struct net_device *dev)
                }
        }
        fep->dirty_tx = (cbd_t *)bdp;
-       spin_unlock(&fep->lock);
+       spin_unlock_irq(&fep->hw_lock);
 }
 
 
@@ -588,6 +594,8 @@ fec_enet_rx(struct net_device *dev)
        fep = netdev_priv(dev);
        fecp = (volatile fec_t*)dev->base_addr;
 
+       spin_lock_irq(&fep->hw_lock);
+
        /* First, grab all of the stats for the incoming packet.
         * These get messed up if we get called due to a busy condition.
         */
@@ -693,6 +701,8 @@ while (!((status = bdp->cbd_sc) & BD_ENET_RX_EMPTY)) {
         */
        fecp->fec_r_des_active = 0;
 #endif
+
+       spin_unlock_irq(&fep->hw_lock);
 }
 
 
@@ -706,11 +716,11 @@ fec_enet_mii(struct net_device *dev)
        uint            mii_reg;
 
        fep = netdev_priv(dev);
+       spin_lock_irq(&fep->mii_lock);
+
        ep = fep->hwp;
        mii_reg = ep->fec_mii_data;
 
-       spin_lock(&fep->lock);
-
        if ((mip = mii_head) == NULL) {
                printk("MII and no head!\n");
                goto unlock;
@@ -727,7 +737,7 @@ fec_enet_mii(struct net_device *dev)
                ep->fec_mii_data = mip->mii_regval;
 
 unlock:
-       spin_unlock(&fep->lock);
+       spin_unlock_irq(&fep->mii_lock);
 }
 
 static int
@@ -741,12 +751,11 @@ mii_queue(struct net_device *dev, int regval, void (*func)(uint, struct net_devi
        /* Add PHY address to register command.
        */
        fep = netdev_priv(dev);
-       regval |= fep->phy_addr << 23;
+       spin_lock_irqsave(&fep->mii_lock, flags);
 
+       regval |= fep->phy_addr << 23;
        retval = 0;
 
-       spin_lock_irqsave(&fep->lock,flags);
-
        if ((mip = mii_free) != NULL) {
                mii_free = mip->mii_next;
                mip->mii_regval = regval;
@@ -763,9 +772,8 @@ mii_queue(struct net_device *dev, int regval, void (*func)(uint, struct net_devi
                retval = 1;
        }
 
-       spin_unlock_irqrestore(&fep->lock,flags);
-
-       return(retval);
+       spin_unlock_irqrestore(&fep->mii_lock, flags);
+       return retval;
 }
 
 static void mii_do_cmd(struct net_device *dev, const phy_cmd_t *c)
@@ -2308,6 +2316,9 @@ int __init fec_enet_init(struct net_device *dev)
                return -ENOMEM;
        }
 
+       spin_lock_init(&fep->hw_lock);
+       spin_lock_init(&fep->mii_lock);
+
        /* Create an Ethernet device instance.
        */
        fecp = (volatile fec_t *) fec_hw[index];