[U-Boot] [PATCH v2 2/5] sunxi: net: Allow the sunxi to set the MAC from an EEPROM

[Olliver Schinagl]

This patch uses the newly introduced Kconfig options to set the MAC
address from an EEPROM, this will be especially useful for the Olimex
OLinuXino series of sunxi boards as they all have an 2k i2c eeprom chip.

The MAC address is in the eeprom is ignored if there is already a MAC
address in the environment or (if enabled) the CRC8 check fails.

Signed-off-by: Olliver Schinagl <o.schinagl at ultimaker.com>
---
 board/sunxi/Kconfig |  4 ++++
 board/sunxi/board.c | 36 ++++++++++++++++++++++++++++++++++++
 net/Kconfig         |  1 +
 3 files changed, 41 insertions(+)

diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
index 2dd9d3b..a2da3a6 100644
--- a/board/sunxi/Kconfig
+++ b/board/sunxi/Kconfig
@@ -339,18 +339,21 @@ config I2C0_ENABLE
 
 config I2C1_ENABLE
 	bool "Enable I2C/TWI controller 1"
+	default y if (NET_ETHADDR_EEPROM_I2C_BUS = 1)
 	default n
 	---help---
 	See I2C0_ENABLE help text.
 
 config I2C2_ENABLE
 	bool "Enable I2C/TWI controller 2"
+	default y if NET_ETHADDR_EEPROM_I2C_BUS = 2
 	default n
 	---help---
 	See I2C0_ENABLE help text.
 
 if MACH_SUN6I || MACH_SUN7I
 config I2C3_ENABLE
+	default y if NET_ETHADDR_EEPROM_I2C_BUS = 3
 	bool "Enable I2C/TWI controller 3"
 	default n
 	---help---
@@ -359,6 +362,7 @@ endif
 
 if MACH_SUN7I
 config I2C4_ENABLE
+	default y if NET_ETHADDR_EEPROM_I2C_BUS = 4
 	bool "Enable I2C/TWI controller 4"
 	default n
 	---help---
diff --git a/board/sunxi/board.c b/board/sunxi/board.c
index 6ac398c..28310a2 100644
--- a/board/sunxi/board.c
+++ b/board/sunxi/board.c
@@ -12,6 +12,7 @@
  */
 
 #include <common.h>
+#include <i2c.h>
 #include <mmc.h>
 #include <axp_pmic.h>
 #include <asm/arch/clock.h>
@@ -23,6 +24,7 @@
 #include <asm/arch/usb_phy.h>
 #include <asm/gpio.h>
 #include <asm/io.h>
+#include <linux/crc8.h>
 #include <nand.h>
 #include <net.h>
 
@@ -510,6 +512,37 @@ void get_board_serial(struct tag_serialnr *serialnr)
 }
 #endif
 
+#if defined(CONFIG_NET_ETHADDR_EEPROM) && defined(CONFIG_NET_ETHADDR_EEPROM_I2C)
+static int read_mac_from_eeprom(uint8_t *mac_addr)
+{
+	uint8_t eeprom[7];
+	int old_i2c_bus;
+
+	old_i2c_bus = i2c_get_bus_num();
+	i2c_set_bus_num(CONFIG_NET_ETHADDR_EEPROM_I2C_BUS);
+	if (i2c_read(CONFIG_NET_ETHADDR_EEPROM_I2C_ADDR,
+		     CONFIG_NET_ETHADDR_EEPROM_OFFSET,
+		     CONFIG_NET_ETHADDR_EEPROM_I2C_ADDRLEN,
+		     eeprom, 7)) {
+		i2c_set_bus_num(old_i2c_bus);
+		puts("Could not read the EEPROM; EEPROM missing?\n");
+		return -1;
+	}
+	i2c_set_bus_num(old_i2c_bus);
+#ifdef CONFIG_NET_ETHADDR_EEPROM_CRC8
+	if (crc8(eeprom, 6) != eeprom[6]) {
+		puts("CRC error on MAC address from EEPROM.\n");
+		return -1;
+	}
+#endif
+	memcpy(mac_addr, eeprom, 6);
+
+	return 0;
+}
+#else
+static int read_mac_from_eeprom(uint8_t *mac_addr) { return -1; }
+#endif
+
 #if !defined(CONFIG_SPL_BUILD)
 #include <asm/arch/spl.h>
 
@@ -553,6 +586,9 @@ int misc_init_r(void)
 	}
 #endif
 
+	if ((!getenv("ethaddr")) && (!read_mac_from_eeprom(mac_addr)))
+		eth_setenv_enetaddr("ethaddr", mac_addr);
+
 	ret = sunxi_get_sid(sid);
 	if (ret == 0 && sid[0] != 0 && sid[3] != 0) {
 		if (!getenv("ethaddr")) {
diff --git a/net/Kconfig b/net/Kconfig
index aced51e..0f4cc5a 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -8,6 +8,7 @@ menuconfig NET
 if NET
 
 config NET_ETHADDR_EEPROM
+	depends on ARCH_SUNXI
 	bool "Get ethaddr from eeprom"
 	help
 	  Selecting this will try to get the Ethernet address from an onboard
-- 
2.6.2