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>

1 files changed, 33 insertions, 22 deletions

diff --git a/drivers/net/fec.c b/drivers/net/fec.c
index 5f9c2c1a9d40..32a4f17d35fc 100644
--- 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];