[LinuxBIOS] Messing with CAR in a big way

ron minnich rminnich at gmail.com
Sat Jan 12 01:43:10 CET 2008

On Jan 11, 2008 4:33 PM, Carl-Daniel Hailfinger
<c-d.hailfinger.devel.2006 at gmx.net> wrote:
> On 12.01.2008 01:18, Rudolf Marek wrote:

> > Temporary data stored in the cache during boot cannot be written back
> > to DRAM
> > after enabling the
> > DRAM controller using a CLFLUSH or WBINVB instruction. The cache should be
> > invalidated after the DRAM controller is initialized with an INVD
> > instruction.

are you sure? I ask because what i am doing on LX (that worked) is to
enable the cache, copy the stack back over itself, and then wbinvd. It
worked well, I think it might work on k8.

> OK, then we simply copy the whole CAR area to some backup memory
> location, disable CAR, then INVD and copy everything back to the
> original location. That way, moving the stack with all of its nasty side
> effects will not happen.

Just see the LX. Copy stack onto itself. Works fine. This was Marc
Jone's idea. Just make sure the
stack is in an area back by memory, like 0x80000



More information about the coreboot mailing list