[PATCH] sk98lin: not doing high dma properly

Sk98lin 64bit memory handling is wrong. It doesn't set the
highdma flag; i.e. the kernel always does bounce buffers.
It doesn't fallback to 32 bit mask if it can't get 64 bit mask.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

drivers/net/sk98lin/skge.c

@@ -4775,16 +4775,30 @@ static int __devinit skge_probe_one(struct pci_dev *pdev,
 	struct net_device	*dev = NULL;
 	static int boards_found = 0;
 	int error = -ENODEV;
+	int using_dac = 0;
 	char DeviceStr[80];
 
 	if (pci_enable_device(pdev))
 		goto out;
 
 	/* Configure DMA attributes. */
-	if (pci_set_dma_mask(pdev, DMA_64BIT_MASK) &&
-	    pci_set_dma_mask(pdev, DMA_32BIT_MASK))
-		goto out_disable_device;
-
+	if (sizeof(dma_addr_t) > sizeof(u32) &&
+	    !(error = pci_set_dma_mask(pdev, DMA_64BIT_MASK))) {
+		using_dac = 1;
+		error = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
+		if (error < 0) {
+			printk(KERN_ERR "sk98lin %s unable to obtain 64 bit DMA "
+			       "for consistent allocations\n", pci_name(pdev));
+			goto out_disable_device;
+		}
+	} else {
+		error = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
+		if (error) {
+			printk(KERN_ERR "sk98lin %s no usable DMA configuration\n",
+			       pci_name(pdev));
+			goto out_disable_device;
+		}
+	}
 
 	if ((dev = alloc_etherdev(sizeof(DEV_NET))) == NULL) {
 		printk(KERN_ERR "Unable to allocate etherdev "
@@ -4843,6 +4857,9 @@ static int __devinit skge_probe_one(struct pci_dev *pdev,
 #endif
 	}
 
+	if (using_dac)
+		dev->features |= NETIF_F_HIGHDMA;
+
 	pAC->Index = boards_found++;
 
 	if (SkGeBoardInit(dev, pAC))
@@ -4919,6 +4936,9 @@ static int __devinit skge_probe_one(struct pci_dev *pdev,
 #endif
 		}
 
+		if (using_dac)
+			dev->features |= NETIF_F_HIGHDMA;
+
 		if (register_netdev(dev)) {
 			printk(KERN_ERR "sk98lin: Could not register device for seconf port.\n");
 			free_netdev(dev);