Resource base 0x1xy for AMD K8 northbridge.

Eric W. Biederman ebiederman at
Wed Nov 24 02:33:00 CET 2004

Li-Ta Lo <ollie at> writes:

> Eric,
> Why you add 0x100 to the resource base register for AMDK8 Function 1, in
> find_mem|io_pair()?

As a general convention I name the resources as the address in the configuration
space.  The k8 distributes functionality across it's pci configuration space,
which makes it atypical in a number of respects.  

In this case the bridges are all in function 0, but the bars for those
bridges are actually in function 1.  Since I am reporting those resources
on function 0 I add 0x100 to indicate that those resources are really
in function 1.    Which is simple and keeps me safe from most conflicts.

It looks like I am also playing with the low address bits to distinguish
which link I am actually dealing with.

Does that make sense?

The resource->index is arbitrary but I try to keep to a convention where
looking at it you can tell which configuration register you are dealing


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