net: dm9000: random mac address support

When an unprogrammed EEPROM is attached to a dm9000, the dm9000 will
come up with a invalid MAC address of ff:ff:ff:ff:ff:ff.  Add code that
gets enabled if CONFIG_RANDOM_MACADDR is enabled that generates a random
(and valid) locally administered MAC address that allows the system to
network boot until a real MAC address can be configured.

Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com>

drivers/net/dm9000x.c

@@ -342,6 +342,15 @@ static int dm9000_init(struct eth_device *dev, bd_t *bd)
 	DM9000_iow(DM9000_ISR, ISR_ROOS | ISR_ROS | ISR_PTS | ISR_PRS);
 
 	printf("MAC: %pM\n", dev->enetaddr);
+	if (!is_valid_ether_addr(dev->enetaddr)) {
+#ifdef CONFIG_RANDOM_MACADDR
+		printf("Bad MAC address (uninitialized EEPROM?), randomizing\n");
+		eth_random_enetaddr(dev->enetaddr);
+		printf("MAC: %pM\n", dev->enetaddr);
+#else
+		printf("WARNING: Bad MAC address (uninitialized EEPROM?)\n");
+#endif
+	}
 
 	/* fill device MAC address registers */
 	for (i = 0, oft = DM9000_PAR; i < 6; i++, oft++)