[COMMIT] pirq_routing.c

Ronald G. Minnich rminnich at lanl.gov
Thu Nov 14 00:12:01 CET 2002

On Thu, 14 Nov 2002, Andrew Ip wrote:

> On pcm-5823,
> 1. pirq routing table failed to copy when COMPRESS is on

This one is weird. Oh, wait, I get it, see below. This one is not weird, 
it makes sense now.

> 2. When COMPRESS is off, pirq routing table also failed to copy to 0xf0000.
> However, Linux kernel is able to find the pirq routing table at 0xc00f6c90.

I get this now. So in other words, it is not getting copied, but the
kernel is finding the table in FLASH since it is uncompressed. Now I
wonder why linuxbios would try to copy to f0000, since that is a FLASH
area. I think it is because linuxbios is now thinking that the memory hole
at 0xf0000 is not there, and that it is dram. We need to see what
assumptions linuxbios is making about the memory hole at 0xf0000.
Something has changed recently.

The reason it won't work with COMPRESS: The PIRQ table is compressed, 
hence unreadable; the copy to 0xf0000 fails because it has no memory. So, 
in the end, Linux can not find the table in RAM or in FLASH.

It is a good thing in the long term to make the 0xf0000 region RAM, but 
something has obviously gone wrong somewhere.

I will have to see how the MTRRs are set on the pcm-5823.


More information about the coreboot mailing list