u-boot has a standard "serial#" environment variable that is suitable for storing the iSerial number we will supply via the USB device descriptor. serial# is automatically picked up by the disk subsystem in u-boot - thus providing a handy unique identifier in /dev/disk/by-id as detailed below.
Storing the hardware serial identifier in serial# means we can change the serial# if we want before USB enumeration - thus making iSerial automatic via OTP but overridable if necessary.
This patch reads the defined OTP fuse and sets environment variable "serial#" to the value read.
With this patch in place the USB mass storage device will appear in /dev/disk/by-id with a unique name based on the OTP value. For example
/dev/disk/by-id/usb-Linux_UMS_disk_0_WaRP7-0xf42400d3000001d4-0:0
Signed-off-by: Bryan O'Donoghue bryan.odonoghue@linaro.org Cc: Fabio Estevam fabio.estevam@nxp.com Cc: Rui Miguel Silva rui.silva@linaro.org Cc: Ryan Harkin ryan.harkin@linaro.org --- board/warp7/warp7.c | 14 ++++++++++++++ include/configs/warp7.h | 3 +++ 2 files changed, 17 insertions(+)
diff --git a/board/warp7/warp7.c b/board/warp7/warp7.c index d422d63..327f656 100644 --- a/board/warp7/warp7.c +++ b/board/warp7/warp7.c @@ -23,6 +23,8 @@ #include <power/pmic.h> #include <power/pfuze3000_pmic.h> #include "../freescale/common/pfuze.h" +#include <asm/setup.h> +#include <asm/bootm.h>
DECLARE_GLOBAL_DATA_PTR;
@@ -186,6 +188,10 @@ int board_usb_phy_mode(int port) int board_late_init(void) { struct wdog_regs *wdog = (struct wdog_regs *)WDOG1_BASE_ADDR; +#ifdef CONFIG_SERIAL_TAG + struct tag_serialnr serialnr; + char serial_string[0x20]; +#endif
imx_iomux_v3_setup_multiple_pads(wdog_pads, ARRAY_SIZE(wdog_pads));
@@ -197,5 +203,13 @@ int board_late_init(void) */ clrsetbits_le16(&wdog->wcr, 0, 0x10);
+#ifdef CONFIG_SERIAL_TAG + /* Set serial# standard environment variable based on OTP settings */ + get_board_serial(&serialnr); + snprintf(serial_string, sizeof(serial_string), "WaRP7-0x%08x%08x", + serialnr.low, serialnr.high); + env_set("serial#", serial_string); +#endif + return 0; } diff --git a/include/configs/warp7.h b/include/configs/warp7.h index fe96988..0c3b605 100644 --- a/include/configs/warp7.h +++ b/include/configs/warp7.h @@ -24,6 +24,9 @@ #define CONFIG_SYS_FSL_ESDHC_HAS_DDR_MODE #define CONFIG_SYS_MMC_IMG_LOAD_PART 1
+/* Switch on SERIAL_TAG */ +#define CONFIG_SERIAL_TAG + #define CONFIG_DFU_ENV_SETTINGS \ "dfu_alt_info=boot raw 0x2 0x400 mmcpart 1\0" \