[PATCH] bcm43xx-softmac: Fix system hang for x86-64 with >1GB RAM

The bcm43xx-softmac software currently fails when running on x86_64 systems
with more than 1GB RAM and one of the card variants with 30-bit DMA addressing.
This patch uses the address extension bits in the hardware to set the correct
DMA mask for the specific card in use.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/bcm43xx/bcm43xx_dma.c

@@ -705,11 +705,30 @@ int bcm43xx_dma_init(struct bcm43xx_private *bcm)
 	struct bcm43xx_dmaring *ring;
 	int err = -ENOMEM;
 	int dma64 = 0;
-	u32 sbtmstatehi;
+	u64 mask = bcm43xx_get_supported_dma_mask(bcm);
+	int nobits;
 
-	sbtmstatehi = bcm43xx_read32(bcm, BCM43xx_CIR_SBTMSTATEHIGH);
-	if (sbtmstatehi & BCM43xx_SBTMSTATEHIGH_DMA64BIT)
+	if (mask == DMA_64BIT_MASK) {
 		dma64 = 1;
+		nobits = 64;
+	} else if (mask == DMA_32BIT_MASK)
+		nobits = 32;
+	else
+		nobits = 30;
+	err = pci_set_dma_mask(bcm->pci_dev, mask);
+	err |= pci_set_consistent_dma_mask(bcm->pci_dev, mask);
+	if (err) {
+#ifdef CONFIG_BCM43XX_PIO
+		printk(KERN_WARNING PFX "DMA not supported on this device."
+					" Falling back to PIO.\n");
+		bcm->__using_pio = 1;
+		return -ENOSYS;
+#else
+		printk(KERN_ERR PFX "FATAL: DMA not supported and PIO not configured. "
+				    "Please recompile the driver with PIO support.\n");
+		return -ENODEV;
+#endif /* CONFIG_BCM43XX_PIO */
+	}
 
 	/* setup TX DMA channels. */
 	ring = bcm43xx_setup_dmaring(bcm, 0, 1, dma64);
@@ -755,8 +774,7 @@ int bcm43xx_dma_init(struct bcm43xx_private *bcm)
 		dma->rx_ring3 = ring;
 	}
 
-	dprintk(KERN_INFO PFX "%s DMA initialized\n",
-			dma64 ? "64-bit" : "32-bit");
+	dprintk(KERN_INFO PFX "%d-bit DMA initialized\n", nobits);
 	err = 0;
 out:
 	return err;