[flashrom] Sapphire IPC-E350M1 mainboard read success

[Stefan Tauner]

On Fri, 19 Jul 2013 19:17:44 +0200
Stefan Tauner <stefan.tauner at student.tuwien.ac.at> wrote:

> On Fri, 19 Jul 2013 19:24:36 +0400
> Антон Кочков <anton.kochkov at gmail.com> wrote:
> 
> > Just downloaded flashrom trunk and tried to read
> > http://paste.flashrom.org/view.php?id=1695 - as you can see it fails
> 
> very interesting result (with r1701). Thanks for testing that.
> Can you please test r1700, and if that does not help r1697?

Carl-Daniel explained what happens on IRC:

"there is an old standard (never mentioned anywhere, but tradition for
all 32bit capable chipsets since forever). the agreed-upon convention
is that the ROM mapping window is exactly 16 MB big, and top-aligned to
4G. for LPC/FWH, there's also the convention that (from top of the
window to bottom of the window) you have 4 MB flash space, 4 MB
register space, 4 MB flash space, 4 MB register space. this also means
the BIOS usually tells the OS that the top 16 MB are reserved, but
stuff below the top 16 MB may be marked as unused or unusable. and
there are some newer standards which place certain mmapped registers
directly below the top 16 MB. so even on SPI chipsets, mapping more
than 16 MB is simply impossible. and if it works, the SPI chip wouldn't
be completely accessible; you only get the last 16 MB of a bigger flash
chip."

The good news is that we do not face some weird problems with C types
and that I am aware of yet another detail to fix for big flash chips.
The bad news is that we can not even probe for those large chips on
some chipsets and since we can not easily control this have to remove
them for now. This shouldn't be a huge problem for anybody....

Thanks a lot for noticing this problem before we tagged 0.9.7 :)
-- 
Kind regards/Mit freundlichen Grüßen, Stefan Tauner