Re: 2.6.10-rc2 doesn't boot (if no floppy device)

[Len Brown <len.brown@intel.com>]

On Mon, 2004-11-22 at 15:02, Linus Torvalds wrote:
> 
> On Mon, 22 Nov 2004, Len Brown wrote:
> >
> > When we enable a link, we must set the ELCR.
> > When we disable a link, we must clear the ELCR.
> > We need to be able to enable and disable all links in the system.
> >
> > The bug was that while we were were setting the ELCR
> > when we enabled a link, we were not clearing it when we disabled
> one.
> 
> Fair enough. ...

> But feel free to send me a patch that doesn't just clear ELCR totally,
> but clears the bits we are disabling. I just don't believe in the
> "let's just clear everything" approach.

Will do.

> 
> > But if you're more comfortable with disabling the associated ELCR
> bit> only when we disable links directed at that entry, we can do that
> too.
> > The complication with that approach is that links are many to one,
> so
> > clearing the bit without disabling all links directed to that entry
> > would result in a failure.  Also, the SCI uses the ELCR too, and it
> > isn't described by links at all.
> 
> Wouldn't it be nicer to take the _reverse_ approach: let's assume that
> any PCI interrupts that we have already enabled are fine and should
> not be disabled? Mark them in the ELCR, and _report_ when the ELCR
> seems to be incorrect (let's make a wild guess here, and realize that
> the screaming VIA interrupts you talk about are exactly because the
> ELCR was wrong).

I think the VIA case is more complicated than that, but I'll take
another look at it.


thanks,
-Len