r6040: warn about MAC address being unset

Some bootloader/BIOSes do not set the MAC
address, warn about that.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/r6040.c b/drivers/net/r6040.c
index 7ac6fed..3354cce 100644
--- a/drivers/net/r6040.c
+++ b/drivers/net/r6040.c
@@ -1141,6 +1141,11 @@
 	adrp[1] = ioread16(ioaddr + MID_0M);
 	adrp[2] = ioread16(ioaddr + MID_0H);
 
+	/* Some bootloader/BIOSes do not initialize
+	 * MAC address, warn about that */
+	if (!(adrp[0] || adrp[1] || adrp[2]))
+		printk(KERN_WARNING DRV_NAME ": MAC address not initialized\n");
+
 	/* Link new device into r6040_root_dev */
 	lp->pdev = pdev;
 	lp->dev = dev;