iMX6, CONFIG_IMX_HAB and fuse_read()

[Lisandro Pérez Meyer]

Hi!

I am currently not subscribed (already filled the form waiting for
confirmation), so please CC me for the moment.

I am trying to enable Secure Boot/HAB on u-boot 2022.07. In a previous
version this was achieved by enabling CONFIG_SECURE_BOOT, which was
then renamed to CONFIG_IMX_HAB.

Now if I enable this option I get:

```
| arm-tdx-linux-gnueabi-ld.bfd: arch/arm/mach-imx/hab.o: in function
`imx_hab_is_enabled':
| /home/lisandro/myproject/build/tmp/work/apalis_imx6-tdx-linux-gnueabi/u-boot-toradex/1_2022.07-r0/git/arch/arm/mach-imx/hab.c:875:
undefined reference to `fuse_read'
| make[2]: *** [/home/lisandro/myproject/build/tmp/work/apalis_imx6-tdx-linux-gnueabi/u-boot-toradex/1_2022.07-r0/git/scripts/Makefile.spl:525:
spl/u-boot-spl] Error 1
```

Now without IMX_HAB enabled CONFIG_CMD_FUSE is enabled and actually
works, ie, I can read the fuses from u-boot's command line. So I'm
suspecting this is just a missing condition... somewhere. But so far I
have not been able to detect exactly where. Can anyone give me a
non-NULL pointer on this?

Thanks in advance, Lisandro.

--
Lisandro Pérez Meyer
Embedded Platform Engineer