flashrom: Add -T to automatically test all flash chip operations

[stuge]

Maybe require -f to actually perform the test, since it will potentially fail to restore the flash chip to it's original state.

[hailfinger]

Good idea.

[hailfinger]

For -T to work, you have to remove the mutual exclusion between -r and -w in a meaningful way. This may require a rewrite of the main loop.

[stuge]

dup #103

[stuge]

Carl-Daniel Hailfinger wrote:

The self-test mode has to execute:

1. read (and store on disk)

I think the point is that it goes to disk to allow out-of-band restoration in case writing back with flashrom fails?

I would prefer no file. I don't want to have to remove files after testing, and not having a file would encourage testing strictly with flash chips without valuable contents. I think that is a very good thing™!

There's always -r to do a manual backup first, but I like the idea of making the difficult path more labor intense, to discourage testing with critical flash chips.

3. write (old contents)

I think it has to write all 0 to the chip rather than the original contents. If the chip is blank to begin with there would be a false positive when erase or write does not work, and flashrom can't tell.

[hailfinger]

Flashrom now has a partial test infrastructure (among others, it can generate test patterns for write). The rest of this ticket is indeed a dup of #103.