Subject: Re: 7025-F40 Support
To: Cory Bajus <cbajus@mts.net>
From: Tim Rightnour <root@garbled.net>
List: port-prep
Date: 09/11/2006 14:44:27
On 11-Sep-2006 Cory Bajus wrote:
> I don't think slots 1&2 are on a secondary bus.  According to the
> IBM docs, slots 1-3 are in a primary bus and 4-9 are on a secondary
> bus (i.e. behind a ppb).  The 7043-140 is similar, with slots 1&2
> primary and 3-5 secondary.  What makes slots 1&2 unique on F40's is
> that they are 64-bit slots - do these need to be treated differently
> by NetBSD?

According to the residual data: 
http://www.garbled.net/tmp/residual/residual.7025-F40

There are three complete PCI bridges on the machine.  When scanning the primary
host bridge, you see the pci-pci bridge on there.  However, even scanning both
bridges, we never see the third bridge.  Given the fact that they number the
bridge 128, and give a parent locator of 0 (supposedly meaning it's
cpu-attached) I suspect this third bridge is actually a second host bridge.  So
what I think this machine needs is:

pci0 at mainbus
ppb0 at pci0
pci1 at ppb0
pci2 at mainbus

Complications arise here, because the second primary bus seems to have a
different base address than the primary bus, (which makes sense actually).  So
I need to rewrite some of the attachment code in mainbus I believe.

Note that in the residual, "Pci Slot 3" is noted as being under the primary
bus, (DEVICE 2) and slots 1 and 2 are under this third, wierd bus.  The bridge
is listed as having slots 4-9.

Given that you say they are 64 bit slots.. it wouldn't surprise me at all if
IBM put a second primary bus in the machine to make them run extra-fast.

I'd like to see the IBM docs you spoke of..  do you have a part number for the
book, or have it in PDF form?

---
Tim Rightnour <root@garbled.net>
NetBSD: Free multi-architecture OS http://www.netbsd.org/
Genecys: Open Source 3D MMORPG: http://www.genecys.org/