[coreboot] v3 comments - was Serengeti vga hang

[ron minnich]

On Wed, Oct 15, 2008 at 4:10 PM, Marc Jones <Marc.Jones at amd.com> wrote:

> Your explanation of what it is makes sense. What doesn't make sense is that
> it is never called during phase4. It is no better than v2 if name doesn't
> tell you when it is used. The only time it is used is in pci device scan
> which is really phase1.
>

I think you've just pointed out a bug that's been in there since I
brought this code over from v2.

In truth, the v2 use of enable is very inconsistent. I compiled all
the ways that it was used in v2 and it turns out to be pretty ad-hoc.
The reason for this is the very messy nature of pc hardware; as more
and more strange cases showed up, people used device functions in
dfifferent ways.

I think I did not get it right in v3. I think that we're going to have
to go through and fix this ... look at each phase4 enable usage and
see what it really means. Sorry for this mistake.

I think that
phase4_enable_disable needs a new name, which will make it easy to
hunt down usage and try to figure out where it ought to go.

phase4_resource_control? Meaning that it enables or disables resource
read/write depending on enabled? I believe most uses of it belong in
phase3_enable_scan actually.

ron

ron