Re: port-amd64/38682: PCI_BUS_FIXUP is missing from amd64 port

[Andrew Doran <ad%netbsd.org@localhost>]

The following reply was made to PR port-amd64/38682; it has been noted by GNATS.

From: Andrew Doran <ad%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: port-amd64/38682: PCI_BUS_FIXUP is missing from amd64 port
Date: Sun, 18 May 2008 15:34:37 +0100

 On Sun, May 18, 2008 at 02:30:02PM +0000, Jared D. McNeill wrote:
 > The following reply was made to PR port-amd64/38682; it has been noted by 
 > GNATS.
 > 
 > From: "Jared D. McNeill" <jmcneill%invisible.ca@localhost>
 > To: gnats-bugs%NetBSD.org@localhost
 > Cc: port-amd64-maintainer%netbsd.org@localhost, 
 > gnats-admin%netbsd.org@localhost, 
 >  netbsd-bugs%netbsd.org@localhost
 > Subject: Re: port-amd64/38682: PCI_BUS_FIXUP is missing from amd64 port
 > Date: Sun, 18 May 2008 10:25:49 -0400
 > 
 >  Andrew Doran wrote:
 >  
 >  >  It would be nice to do this by default. A comment from Linux
 >  >  drivers/pci/setup-bus.c:
 >  >  
 >  >  138    PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
 >  >  139    requires that if there is no I/O ports or memory behind the
 >  >  140    bridge, corresponding range must be turned off by writing base
 >  >  141    value greater than limit to the bridge's base/limit registers.
 >  >  
 >  >  How does it fail at run time without the FIXUP option?
 >  
 >  Without my patch and FIXUP option, the bridge only has i/o accesses 
 >  enabled, so cbb and fwohci can't map mem space.
 
 Is there a specific error message?
   
 >  FYI I moved bus and addr fixup options to x86 last night, and I'm now 
 >  running a kernel with PCI_BUS_FIXUP and PCI_ADDR_FIXUP instead of the 
 >  patch posted in the PR.
 >  
 >  If you want to turn on those two options by default, I'm all for it.
 
 I'm afraid those might have side effects...
 
 Andrew