net: gem: Allow to set the MAC from an EEPROM

Provide board specific option how to read MAC address from ROM.
Do it in generic way to be reusable by differnet boards.
If this is not enough board specific functions can be created.

Signed-off-by: Joe Hershberger <joe.hershberger@gmail.com> # driver part
Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

arch/arm/mach-zynq/include/mach/sys_proto.h

@@ -19,6 +19,8 @@ extern int zynq_slcr_get_mio_pin_status(const char *periph);
 extern void zynq_ddrc_init(void);
 extern unsigned int zynq_get_silicon_version(void);
 
+int zynq_board_read_rom_ethaddr(unsigned char *ethaddr);
+
 /* Driver extern functions */
 extern void ps7_init(void);
 

board/xilinx/zynq/board.c

@@ -98,6 +98,19 @@ int checkboard(void)
 }
 #endif
 
+int zynq_board_read_rom_ethaddr(unsigned char *ethaddr)
+{
+#if defined(CONFIG_ZYNQ_GEM_EEPROM_ADDR) && \
+    defined(CONFIG_ZYNQ_GEM_I2C_MAC_OFFSET)
+	if (eeprom_read(CONFIG_ZYNQ_GEM_EEPROM_ADDR,
+			CONFIG_ZYNQ_GEM_I2C_MAC_OFFSET,
+			ethaddr, 6))
+		printf("I2C EEPROM MAC address read failed\n");
+#endif
+
+	return 0;
+}
+
 int dram_init(void)
 {
 	int node;

drivers/net/zynq_gem.c

@@ -571,6 +571,23 @@ static void zynq_gem_halt(struct udevice *dev)
 						ZYNQ_GEM_NWCTRL_TXEN_MASK, 0);
 }
 
+__weak int zynq_board_read_rom_ethaddr(unsigned char *ethaddr)
+{
+	return -ENOSYS;
+}
+
+static int zynq_gem_read_rom_mac(struct udevice *dev)
+{
+	int retval;
+	struct eth_pdata *pdata = dev_get_platdata(dev);
+
+	retval = zynq_board_read_rom_ethaddr(pdata->enetaddr);
+	if (retval == -ENOSYS)
+		retval = 0;
+
+	return retval;
+}
+
 static int zynq_gem_miiphy_read(struct mii_dev *bus, int addr,
 				int devad, int reg)
 {
@@ -644,6 +661,7 @@ static const struct eth_ops zynq_gem_ops = {
 	.free_pkt		= zynq_gem_free_pkt,
 	.stop			= zynq_gem_halt,
 	.write_hwaddr		= zynq_gem_setup_mac,
+	.read_rom_hwaddr	= zynq_gem_read_rom_mac,
 };
 
 static int zynq_gem_ofdata_to_platdata(struct udevice *dev)