We have not tested micro-ecc for secure bootloader; since as mentioned earlier we already have a secure boot option which utilizes the hw crypto present in 90x. I have not done footprint analysis though but my guess would be the default secure boot option will have less memory footprint since the crypto functions are present in the ROM.
If you still intend to use micro ecc, you can do so. The porting should not take significant effort. I will just try to provide a brief outline on how to do so (we haven't tried this though)
- Migrate to 43xxx_Wi-Fi/apps/waf/bootloader/bootloader.mk, and add $(NAME)_COMPONENTS += BESL/crypto_internal/micro-ecc in the .mk
- Include uECC.h in the bootloader.c and use uECC as you need it. Also, it is worth checking out the way mbedTLS uses micro-ecc functions inside WICED (Refer: 43xxx_Wi-Fi/WICED/security/BESL/mbedtls_open/library/ecp_alt.c). If your intention is already taken care of by the mbedTLS library, you can compile that as well as a part of bootloader (might need linker script adjustment though)
