Re: CVS commit: src/sys/arch/x86/pci

[David Young <dyoung%pobox.com@localhost>]

On Mon, Feb 04, 2008 at 02:01:38PM +0100, Julio M. Merino Vidal wrote:
> On Jan 14, 2008, at 7:44 PM, David Young wrote:
> 
> >
> >Module Name: src
> >Committed By:        dyoung
> >Date:                Mon Jan 14 18:44:18 UTC 2008
> >
> >Modified Files:
> >     src/sys/arch/x86/pci: pci_machdep.c
> >
> >Log Message:
> >KASSERT() that reads/writes from/to PCI configuration space are
> >aligned on 32-bit boundaries.
> 
> This breaks the mpt(4) driver and does not let NetBSD/amd64 boot  
> successfully in VMware Fusion.  The machine seems to emulate a  
> 53C1030 chip, and sys/dev/pci/mpt_pci.c has:
> 
>       if ((PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_SYMBIOS_1030) &&
>           (PCI_REVISION(pa->pa_class) < 0x08)) {
>               aprint_normal("%s: applying 1030 quirk\n",
>                   mpt->sc_dev.dv_xname);
>               reg = pci_conf_read(pa->pa_pc, pa->pa_tag, 0x6a);
>               reg &= 0x8f;
>               pci_conf_write(pa->pa_pc, pa->pa_tag, 0x6a, reg);
>       }
> 
> Note the 0x6a register value in there, which will trigger the  
> assertion you added.  I've been looking around to see if that value  
> is correct, but the only thing I found is the Linux code which does  
> the same as us (maybe we borrowed the fix from there in the first  
> place, or the other way around).
> 
> Any idea on how to resolve this?

There are two ways to resolve it.  You can delete that code, since both
the read and the write probably failed.  Or, you can read 0x68, apply
mask 0x008f0000, and write back to 0x68, which seems to be intended.

Dave

-- 
David Young             OJC Technologies
dyoung%ojctech.com@localhost      Urbana, IL * (217) 278-3933 ext 24