mx7ulp: add getting a board serial number

Get Unique ID of SoC iMX7ULP, using the logic described in Fusemap
(IMX7ULPRMB2_Rev0_Fusemap) attached in the i.MX 7ULP APRM [1].

[1]
https://www.nxp.com/docs/en/reference-manual/IMX7ULPRMB2.pdf

Signed-off-by: Ricardo Salveti <ricardo@foundries.io>
Co-developed-by: Oleksandr Suvorov <oleksandr.suvorov@foundries.io>
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@foundries.io>
Reviewed-by: Fabio Estevam <festevam@gmail.com>

diff --git a/arch/arm/mach-imx/mx7ulp/soc.c b/arch/arm/mach-imx/mx7ulp/soc.c
index 7f097d6..c90ce22 100644 (file)
--- a/arch/arm/mach-imx/mx7ulp/soc.c
+++ b/arch/arm/mach-imx/mx7ulp/soc.c
@@ -13,6 +13,7 @@
 #include <asm/arch/sys_proto.h>
 #include <asm/mach-imx/boot_mode.h>
 #include <asm/mach-imx/hab.h>
+#include <asm/setup.h>
 #include <linux/bitops.h>
 
 #define PMC0_BASE_ADDR         0x410a1000
@@ -380,3 +381,25 @@ enum boot_device get_boot_device(void)
 
        return boot_dev;
 }
+
+#ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
+/*
+ * OCOTP_CFG (SJC CHALLENGE, Unique ID)
+ * i.MX 7ULP Applications Processor Reference Manual, Rev. 0, 09/2020
+ *
+ * OCOTP_CFG0 offset 0x4B0: 15:0 -> 15:0  bits of Unique ID
+ * OCOTP_CFG1 offset 0x4C0: 15:0 -> 31:16 bits of Unique ID
+ * OCOTP_CFG2 offset 0x4D0: 15:0 -> 47:32 bits of Unique ID
+ * OCOTP_CFG3 offset 0x4E0: 15:0 -> 63:48 bits of Unique ID
+ */
+void get_board_serial(struct tag_serialnr *serialnr)
+{
+       struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR;
+       struct fuse_bank *bank = &ocotp->bank[1];
+       struct fuse_bank1_regs *fuse =
+               (struct fuse_bank1_regs *)bank->fuse_regs;
+
+       serialnr->low = (fuse->cfg0 & 0xFFFF) + ((fuse->cfg1 & 0xFFFF) << 16);
+       serialnr->high = (fuse->cfg2 & 0xFFFF) + ((fuse->cfg3 & 0xFFFF) << 16);
+}
+#endif /* CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG */