[coreboot] v3 HT

[Myles Watson]

> -----Original Message-----
> From: Marc Jones [mailto:Marc.Jones at amd.com]
> Sent: Monday, October 27, 2008 3:10 PM
> To: Myles Watson
> Cc: 'ron minnich'; 'Coreboot'
> Subject: Re: [coreboot] v3 HT
> 
> Myles Watson wrote:
> >
> >> -----Original Message-----
> >> From: ron minnich [mailto:rminnich at gmail.com]
> >> Sent: Monday, October 27, 2008 8:57 AM
> >> To: Myles Watson
> >> Cc: Coreboot
> >> Subject: Re: [coreboot] v3 HT
> >>
> >> On Mon, Oct 27, 2008 at 7:48 AM, Myles Watson <mylesgw at gmail.com>
> wrote:
> >>
> >>> I don't think we need to expand the dts to fix this, we just need to
> >> make
> >>> the code match the structure.
> >> Do you have a rough idea of how this would look in the code? This is a
> >> good catch.
> >
> > Right now the code goes through the list of children and initializes
> them as
> > bridges, without checking to see that they are.  Then it enumerates them
> > with the pci code.
> >
> > I think we'd have to find the children that are bridges and then
> enumerate
> > them with the list of children, so that we can pass parameters
> correctly.  I
> > don't think it would be too hard.
> >
> > 1. Find bridges and set them to not decode
> > 2. Set first bridge to decode all device numbers (HT Unit IDs)
> > 3. Do PCI scan on bridge with remaining non-bridge children
> > 4. Find next bridge
> > 5. Set to decode next device numbers
> > 6. Goto 3
> 
> I think that the dts is can/should to handle arbitrary bus numbering
> (since a bridge can be plugged into any slot making everything change).
> The numbers are not so important if as long as the tree has the same
> connections (bridgeA has device 1, 2, 3 and bridgeB has x, y, z).
> 
> I don't think that you need a bridge scan before the device scan. It can
> be done as one. The device tree just needs to note the appropriate
> decode (bus number) for the bridge and the devices under it. Also, If
> the bus is already numbered we we shouldn't change it. Just use what is
> set.

So the collapse existing enumeration needs to be taken out?

Thanks,
Myles