forcedeth: phy status fix

The driver needs to ack only the phy status bits that it is currently
handling and preserve the other bits for the other handlers. For
example, when reading/writing from the phy, it should not clear the link
change interrupt bit. This will cause a missing link change interrupt.

Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/forcedeth.c

@@ -323,8 +323,8 @@ enum {
 	NvRegMIIStatus = 0x180,
 #define NVREG_MIISTAT_ERROR		0x0001
 #define NVREG_MIISTAT_LINKCHANGE	0x0008
-#define NVREG_MIISTAT_MASK		0x000f
-#define NVREG_MIISTAT_MASK2		0x000f
+#define NVREG_MIISTAT_MASK_RW		0x0007
+#define NVREG_MIISTAT_MASK_ALL		0x000f
 	NvRegMIIMask = 0x184,
 #define NVREG_MII_LINKCHANGE		0x0008
 
@@ -1064,7 +1064,7 @@ static int mii_rw(struct net_device *dev, int addr, int miireg, int value)
 	u32 reg;
 	int retval;
 
-	writel(NVREG_MIISTAT_MASK, base + NvRegMIIStatus);
+	writel(NVREG_MIISTAT_MASK_RW, base + NvRegMIIStatus);
 
 	reg = readl(base + NvRegMIIControl);
 	if (reg & NVREG_MIICTL_INUSE) {
@@ -2995,7 +2995,7 @@ static void nv_link_irq(struct net_device *dev)
 	u32 miistat;
 
 	miistat = readl(base + NvRegMIIStatus);
-	writel(NVREG_MIISTAT_MASK, base + NvRegMIIStatus);
+	writel(NVREG_MIISTAT_LINKCHANGE, base + NvRegMIIStatus);
 	dprintk(KERN_INFO "%s: link change irq, status 0x%x.\n", dev->name, miistat);
 
 	if (miistat & (NVREG_MIISTAT_LINKCHANGE))
@@ -4870,7 +4870,7 @@ static int nv_open(struct net_device *dev)
 
 	writel(0, base + NvRegMIIMask);
 	writel(NVREG_IRQSTAT_MASK, base + NvRegIrqStatus);
-	writel(NVREG_MIISTAT_MASK2, base + NvRegMIIStatus);
+	writel(NVREG_MIISTAT_MASK_ALL, base + NvRegMIIStatus);
 
 	writel(NVREG_MISC1_FORCE | NVREG_MISC1_HD, base + NvRegMisc1);
 	writel(readl(base + NvRegTransmitterStatus), base + NvRegTransmitterStatus);
@@ -4908,7 +4908,7 @@ static int nv_open(struct net_device *dev)
 
 	nv_disable_hw_interrupts(dev, np->irqmask);
 	pci_push(base);
-	writel(NVREG_MIISTAT_MASK2, base + NvRegMIIStatus);
+	writel(NVREG_MIISTAT_MASK_ALL, base + NvRegMIIStatus);
 	writel(NVREG_IRQSTAT_MASK, base + NvRegIrqStatus);
 	pci_push(base);
 
@@ -4931,7 +4931,7 @@ static int nv_open(struct net_device *dev)
 	{
 		u32 miistat;
 		miistat = readl(base + NvRegMIIStatus);
-		writel(NVREG_MIISTAT_MASK, base + NvRegMIIStatus);
+		writel(NVREG_MIISTAT_MASK_ALL, base + NvRegMIIStatus);
 		dprintk(KERN_INFO "startup: got 0x%08x.\n", miistat);
 	}
 	/* set linkspeed to invalid value, thus force nv_update_linkspeed
@@ -5299,7 +5299,7 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i
 		phystate &= ~NVREG_ADAPTCTL_RUNNING;
 		writel(phystate, base + NvRegAdapterControl);
 	}
-	writel(NVREG_MIISTAT_MASK, base + NvRegMIIStatus);
+	writel(NVREG_MIISTAT_MASK_ALL, base + NvRegMIIStatus);
 
 	if (id->driver_data & DEV_HAS_MGMT_UNIT) {
 		/* management unit running on the mac? */