[U-Boot] SPI flash protection

[Reinhard Meyer <u-boot@emk-elektronik.de>]

Dear Albert ARIBAUD, Simon Guinot,
>
>>>> Here is the protect area map for a MX25L4005A 4Mb flash:
>>>>
>>>>     bit  2 1 0 | protect level
>>>>    ____________|_______________
>>>>          0 0 0 | none
>>>>          0 0 1 | block 7
>>>>          0 1 0 | block 6-7
>>>>          0 1 1 | block 4-7
>>>>          1 * * | all
>> Block size is 64KB. The compiled U-Boot image is about 220KB and
>> environment is 4KB. So, 4 blocks are required for U-Boot.

I don't know your particular hardware, but is not u-boot (or the
initial bootloader if there is any) fetched from the *beginning*
of the flash?

If so, you would have to *hardware* protect the *entire* flash.

In this case, a *software* protection mechanism like for NOR flash
would be a better choice.

Best Regards,
Reinhard