On Fri, Mar 07, 2003 at 11:27:52AM -0800, David Hopper wrote:

 > Ah, okay...  I didn't think the console was bright enough to cough up what 
 > the driver interface needs.  I really am operating under the assumption 
 > that the present codebase "should just work" with multiple PCI buses, and 
 > go from there.  Then we can call it a bug, and track 4.3.0 without forking 
 > for our tree.  (By the way, how does Open/FreeBSD do this stuff?  Just what 
 > is all that hae_* frobbing stuff that we've thrown out?).

HAE == somethine-or-other Address Extension (Host, I think...) Anyway,
reprogramming it changes the address at which PCI addresses are decoded,
leading to all sorts of lossage if, say, an interrupt were to come in
while it had the wrong value.

 > BusID is general enough right now (BusID PCI:01:xx:xx and BusID 
 > PCI:00:xx:xx), but it just doesn't function correctly in the new scanpci 
 > code (and it needs to, to tell me what the BusID parameters should be).  I 
 > _have_ seen XFree4 work on this AS1200 once before; it was with Simon 
 > Burge's initial patches to the XF code on alpha (January 2001).  That was a 
 > different scanpci codebase-- it's all changed quite a bit since then.

No, that's actually NOT general enough for a system with multiple
primary PCI busses (like the AS1200), since a system like that can
have *multiple* PCI:00:xx:xx busses.

NetBSD/alpha tries to work around this XFree86 braindamage by limiting
user access to the PCI heirarchy which has the graphics adapter.

-- 
        -- Jason R. Thorpe <thorpej@wasabisystems.com>