where is the crc stored?

What area of memory is the crc stored for a partition?
I would like to find some detailed documentation on the crc (how big is it, where it is stored, how to invalidate to force the booting from a second area).

Dear John Stile,

Which sort of partitions are you talking here?

In general, erasing the whole region will usually work ;-)

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Q:  Why do mountain climbers rope themselves together?
A:  To prevent the sensible ones from going home.

Maybe partition is the wrong word for a memory address region.

I am a total new-bee, but I have read there is a crc check in u-boot.

The crc check can result in a:
Warning: Bad CRC, using default environment

The crc is considered during the bootcmd.

I would like to know where this crc is stored.

I would like to know is it 8-bit, 16-bit, and 32-bit, or other.

Dear John Stile,

Actually there are several such checks, for several different purposes.

THis is when checking if there is a valid environment. So we are talkign about the CRC which protects the persistent environment copy. The structure of this is defined in "include/environment.h", see struct environment_s - as you can see, this is a CRC32.

No, this has absolutely nothing to do with bootcmd.

In the first 4 bytes of the external representation of the environment.

32 bit.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
The ultimate barrier is one's viewpoint.
                        - Terry Pratchett, _The Dark Side of the Sun_