[COMMIT] Infrastructure Updates 4

Eric W. Biederman ebiederman at lnxi.com
Tue Sep 2 15:11:01 CEST 2003


Stefan Reinauer <stepan at suse.de> writes:

> * Eric W. Biederman <ebiederman at lnxi.com> [030902 19:28]:
> > If you want all of your hypertransport devices to be on bus 0, that is
> > feasible but it will take a little more work.  Right now each
> > hypertranport chain get's it's own bus.
> 
> What is missing to achieve this? 

Just a little code.  Merging busses into bus 0 is an interesting
logicistics feat, but the current infrastructure will allow it.

> Can this cause trouble with current board implementations? 

Not it is software only.

> In the Tyan update code, some hardcoded bus numbers were changed.

We should be able to complete remove that.  Right now each
Hypertransport chains appears to be it's own bus and all of that
information is dynamically calculated.

The busses that are Hypertranpsort chains are enumerated just like
other busses.  

The way to look at the code is that:
- device.c has the logic to enumerate and assign resources to devices and busses.
- pci_device.c has the methods for doing that on pci devices.
- hypertransport.c has the methods for doing that with hypertranport devices.
- northbridge/amd/amdk8/northbridge.c has the drivers for the amdk8 specific
  northbridge.

In short dynamic resource assignment should now be pretty simple and should
remove the need for most of the hard codes. 

I have committed the code not in a final perfect state.  But in a state where
it works well enough to be useful.  And whatever details we encounter are minor
things.

Passing information to the dynamic device tree from the static device
tree is currently a weak area.  But we are building one tree from the
other so it is just a matter of a small amount of refactoring if we
want to do something better.   

Basically what remains is to dive into the code see what it is doing,
and tweak it a little if is not doing quite the right thing.  But
usually all that needs to happen is to improve a method of a device so
that it operates better.

Eric




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