+/*
+ * AT24C128N EEPROM at I2C0-0x53.
+ *
+ * That Atmel EEPROM has 128kbit of memory (16kByte) divided into 256 pages
+ * of 64 bytes per page. The chip uses 2-byte addresses and has a max write
+ * cycle time of 20ms according to the datasheet.
+ *
+ * NOTE: Our environment is stored on regular direct-attached FLASH, this
+ * chip is only used as a write-protected backup for certain key settings
+ * such as the serial# and macaddr values. (EG: "env import")
+ */
+#define CONFIG_CMD_EEPROM
+#define CONFIG_ENV_EEPROM_IS_ON_I2C
+#define CONFIG_SYS_I2C_EEPROM_ADDR 0x53
+#define CONFIG_SYS_I2C_EEPROM_ADDR_LEN 2
+#define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS 6 /* 1 << 6 == 64 byte pages */
+#define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS 21
+
+/*
+ * PCA9554 is at I2C1-0x3f (I know it says "PCA953X", it's a PCA9554). You
+ * must first select the I2C1 bus with "i2c dev 1" or the "pca953x" command
+ * will not be able to access the chip.
+ */