The tester registers provide a unique chip-level identifier which get_board_serial() returns in a "struct tag_serialnr".
This patch documents the properties of the registers; in summary. 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.odonog...@linaro.org> Cc: Fabio Estevam <fabio.este...@nxp.com> Cc: Peng Fan <peng....@nxp.com> Cc: Stefano Babic <sba...@denx.de> Reviewed-by: Fabio Estevam <fabio.este...@nxp.com> --- arch/arm/mach-imx/mx7/soc.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/arm/mach-imx/mx7/soc.c b/arch/arm/mach-imx/mx7/soc.c index 1602585..fb92a26 100644 --- a/arch/arm/mach-imx/mx7/soc.c +++ b/arch/arm/mach-imx/mx7/soc.c @@ -202,6 +202,27 @@ int arch_misc_init(void) #endif #ifdef CONFIG_SERIAL_TAG +/* + * 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 + */ void get_board_serial(struct tag_serialnr *serialnr) { struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR; -- 2.7.4 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot