From: Fabio Estevam festevam@denx.de
The serial number is located at offset 0x14 of the EEPROM under i2c0 bus at address 0x54.
To print the serial number in Linux:
SERNUM=$(cat /proc/device-tree/serial-number) echo $SERNUM
Signed-off-by: Fabio Estevam festevam@denx.de --- .../imx8mm-cl-iot-gate/imx8mm-cl-iot-gate.c | 50 +++++++++++++++++++ 1 file changed, 50 insertions(+)
diff --git a/board/compulab/imx8mm-cl-iot-gate/imx8mm-cl-iot-gate.c b/board/compulab/imx8mm-cl-iot-gate/imx8mm-cl-iot-gate.c index 779b64b140ad..27200f728efe 100644 --- a/board/compulab/imx8mm-cl-iot-gate/imx8mm-cl-iot-gate.c +++ b/board/compulab/imx8mm-cl-iot-gate/imx8mm-cl-iot-gate.c @@ -463,6 +463,52 @@ static int setup_mac_address(void) return 0; }
+static int read_serial_number(void) +{ + unsigned char serialnumber[6]; + unsigned char reversed[6]; + char serial_string[12]; + struct udevice *dev; + int ret, off, i; + + off = fdt_path_offset(gd->fdt_blob, "eeprom0"); + if (off < 0) { + printf("No eeprom0 path offset found in DT\n"); + return off; + } + + ret = uclass_get_device_by_of_offset(UCLASS_I2C_EEPROM, off, &dev); + if (ret) { + printf("%s: Could not find EEPROM\n", __func__); + return ret; + } + + ret = i2c_set_chip_offset_len(dev, 1); + if (ret) + return ret; + + ret = i2c_eeprom_read(dev, 0x14, serialnumber, sizeof(serialnumber)); + if (ret) { + printf("%s: Could not read EEPROM\n", __func__); + return ret; + } + + for (i = sizeof(serialnumber) - 1; i >= 0; i--) + reversed[i] = serialnumber[sizeof(serialnumber) - 1 - i]; + + for (i = 0; i < sizeof(reversed); i++) { + serial_string[i * 2] = (reversed[i] >> 4) & 0xf; + serial_string[i * 2 + 1] = reversed[i] & 0xf; + } + + for (i = 0; i < sizeof(serial_string); i++) + serial_string[i] += '0'; + + env_set("serial#", serial_string); + + return 0; +} + int board_late_init(void) { int ret; @@ -476,5 +522,9 @@ int board_late_init(void) if (ret < 0) printf("Cannot set MAC address from EEPROM\n");
+ ret = read_serial_number(); + if (ret < 0) + printf("Cannot read serial number from EEPROM\n"); + return 0; }