I have finalised my set-up for secure boot, and am at the stage of closing the device by setting the SEC_CONFIG to 1. However, when trying to blow the bit, I get the following error:
>TX6Q U-Boot > fuse prog -y 0 6 0x2
Programming bank 0 word 0x00000006 to 0x00000002...
mxc_ocotp fuse_prog(): Access protect error
It's a i-MX6 Q module