net: ethernet: dm9000: Accept a MAC address as a bootarg for CI20.

The MAC address for the CI20's DM9000 is stored in EEPROM on a different
part of the board. Previously, the DM9000 would make up a random MAC
after failing to read its own EEPROM. This commit makes it possible for
U-BOOT to pass the MAC address to the DM9000 driver. Such as:

bootargs="dm9000.mac_addr=${ethaddr}"

Note: This isn't the "correct" way to do this, but will do for now. The correct
method would be to recompile U-BOOT with CONFIG_OF_LIBFDT and CONFIG_FIT
enabled. Then the kernel should be compiled as a FIT image and U-BOOT can then
add an entry to the DM9000's DT node to set the MAC address (local-mac-address
= [xx xx xx xx xx xx];).

Signed-off-by: Harvey Hunt <harvey.hunt@imgtec.com>

Author: HarveyHunt

drivers/net/ethernet/davicom/dm9000.c

@@ -46,6 +46,11 @@
 
 #include "dm9000.h"
 
+#ifdef CONFIG_JZ4780_CI20
+static char *mac_addr = NULL;
+module_param(mac_addr, charp, 0);
+#endif
+
 /* Board/System/Debug information/definition ---------------- */
 
 #define DM9000_PHY		0x40	/* PHY address 0x01 */
@@ -1438,6 +1443,10 @@ dm9000_probe(struct platform_device *pdev)
 	int reset_gpios;
 	enum of_gpio_flags flags;
 	struct regulator *power;
+#ifdef CONFIG_JZ4780_CI20
+	u8 eth_addr[6];
+	ssize_t sz = 0;
+#endif
 
 	power = devm_regulator_get(dev, "vcc");
 	if (IS_ERR(power)) {
@@ -1666,20 +1675,34 @@ dm9000_probe(struct platform_device *pdev)
 	db->mii.mdio_read    = dm9000_phy_read;
 	db->mii.mdio_write   = dm9000_phy_write;
 
-	mac_src = "eeprom";
+#ifdef CONFIG_JZ4780_CI20
+	mac_src = "bootarg";
+	if (mac_addr)
+		sz = sscanf(mac_addr, "%2x:%2x:%2x:%2x:%2x:%2x",
+				(unsigned int *)eth_addr,
+				(unsigned int *)(eth_addr + 1),
+				(unsigned int *)(eth_addr + 2),
+				(unsigned int *)(eth_addr + 3),
+				(unsigned int *)(eth_addr + 4),
+				(unsigned int *)(eth_addr + 5));
+	if (sz == ETH_ALEN)
+		ether_addr_copy(ndev->dev_addr, eth_addr);
+#endif
 
-	/* try reading the node address from the attached EEPROM */
-	for (i = 0; i < 6; i += 2)
-		dm9000_read_eeprom(db, i / 2, ndev->dev_addr+i);
+	if (!is_valid_ether_addr(ndev->dev_addr)) {
+		/* try reading the node address from the attached EEPROM */
+		mac_src = "eeprom";
+		for (i = 0; i < 6; i += 2)
+			dm9000_read_eeprom(db, i / 2, ndev->dev_addr+i);
+	}
 
 	if (!is_valid_ether_addr(ndev->dev_addr) && pdata != NULL) {
 		mac_src = "platform data";
-		memcpy(ndev->dev_addr, pdata->dev_addr, ETH_ALEN);
+		ether_addr_copy(ndev->dev_addr, pdata->dev_addr);
 	}
 
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		/* try reading from mac */
-
 		mac_src = "chip";
 		for (i = 0; i < 6; i++)
 			ndev->dev_addr[i] = ior(db, i+DM9000_PAR);
@@ -1693,7 +1716,6 @@ dm9000_probe(struct platform_device *pdev)
 		mac_src = "random";
 	}
 
-
 	platform_set_drvdata(pdev, ndev);
 	ret = register_netdev(ndev);