We want to be able to set the USB device descriptor number iSerial number or indeed a disk-label unique identifier based on a chip-specific piece of data for the purposes of differentiating between WaRP7 boards via lsusb when connected to a host machine.
In order to do this we want to have a serial number encoded in hardware, which will persist across bootloader, filesystem and config file changes.
This patch utilises OCOTP_TESTER0 AND OCOTP_TESTER1 respectively for this purpose. OCOTP_TESTER is a unique identifier for each chip representing
31:0 OCOTP_TESTER0 (most significant) - FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID
OCOTP_TESTER1 (least significant) 31:24 - The X-coordinate of the die location on the wafer/SJC CHALLENGE/ Unique ID 23:16 - The Y-coordinate of the die location on the wafer/SJC CHALLENGE/ Unique ID 15:11 - The wafer number of the wafer on which the device was fabricated/SJC CHALLENGE/ Unique ID 10:0 - FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID
The 64 bits of data generate a unique serial number per-chip.
Signed-off-by: Bryan O'Donoghue bryan.odonoghue@linaro.org Cc: Fabio Estevam fabio.estevam@nxp.com Reviewed-by: Rui Miguel Silva rui.silva@linaro.org Reviewed-by: Ryan Harkin ryan.harkin@linaro.org --- board/warp7/warp7.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+)
diff --git a/board/warp7/warp7.c b/board/warp7/warp7.c index d422d63..2cec448 100644 --- a/board/warp7/warp7.c +++ b/board/warp7/warp7.c @@ -23,6 +23,7 @@ #include <power/pmic.h> #include <power/pfuze3000_pmic.h> #include "../freescale/common/pfuze.h" +#include <fuse.h>
DECLARE_GLOBAL_DATA_PTR;
@@ -90,6 +91,58 @@ static struct fsl_esdhc_cfg usdhc_cfg[1] = { {USDHC3_BASE_ADDR}, };
+/* + * OCOTP_TESTER + * i.MX 7Solo Applications Processor Reference Manual, Rev. 0.1, 08/2016 + * OCOTP_TESTER describes a unique ID based on silicon wafer + * and die X/Y position + * + * OCOTOP_TESTER offset 0x410 + * 31:0 fuse 0 + * FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID + * + * OCOTP_TESTER1 offset 0x420 + * 31:24 fuse 1 + * The X-coordinate of the die location on the wafer/SJC CHALLENGE/ Unique ID + * 23:16 fuse 1 + * The Y-coordinate of the die location on the wafer/SJC CHALLENGE/ Unique ID + * 15:11 fuse 1 + * The wafer number of the wafer on which the device was fabricated/SJC + * CHALLENGE/ Unique ID + * 10:0 fuse 1 + * FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID + */ +#define WARP7_USB_SERIALID_BANK 0 +#define WARP7_USB_SERIALID_MSWORD 1 +#define WARP7_USB_SERIALID_LSWORD 2 + +static int warp7_get_serialid(u64 *id) +{ + u32 val; + int ret; + + if (!id) + return -EINVAL; + + /* Read first word */ + ret = fuse_read(WARP7_USB_SERIALID_BANK, WARP7_USB_SERIALID_MSWORD, &val); + if (ret) + goto done; + + *id = val; + *id <<= 32; + + /* Read second word */ + ret = fuse_read(WARP7_USB_SERIALID_BANK, WARP7_USB_SERIALID_LSWORD, &val); + if (ret) + goto done; + + *id |= val; + +done: + return ret; +} + int board_mmc_getcd(struct mmc *mmc) { /* Assume uSDHC3 emmc is always present */