Bug#499501: xserver-xorg-core: does not detect video devices anymore (kfreebsd-amd64)

[Julien Cristau <jcristau@debian.org>]

On Fri, Sep 19, 2008 at 12:50:09 +0200, Petr Salinger wrote:

> I found the cause, there have been change in GNU/kFreeBSD specific headers.
> The identification (struct pcisel) have been extended by domain field in  
> FreeBSD 7.x series. There is a ABI compatibility layer - the reason why  
> 2:1.4.2-1 works. With current interface, the io.pi_sel.pc_domain is not  
> initialized, it contains garbage, in the first iteration
> it have been luckily zeroed -> some entries have been found.
>
> In long term, it should properly handle domains, but in short term
> (for current sid and our lenny snapshot) please, could you add
> the patch bellow. It really does not affect any official release
> architectures.
>
Why should domain be set to 0, as opposed to PCI_DOM_FROM_TAG(tag)?
(I don't really care either way, just trying to understand this.)

FWIW, libpciaccess is used in newer versions of X for this, and has:
#if __FreeBSD_version >= 700053
#define DOMAIN_SUPPORT 1
#else
#define DOMAIN_SUPPORT 0
#endif

and then sets io.pi_sel.pc_domain if DOMAIN_SUPPORT is non-zero.

Cheers,
Julien