PCI bus numbering and orphaned devices

[M. Warner Losh]

In message: <361340000.1055367125 at caspian.scsiguy.com>
            "Justin T. Gibbs" <gibbs at scsiguy.com> writes:
: > I'm thinking that the loop should be more like:
: >
: > 		pcifunchigh = 0;
: > 		f = 0;
: > 		hdrtype	= REG(PCIR_HEADERTYPE, 1);
: > 		if (hdrtype & 0x7f > 2)
: > 			continue;
: 
: My only complaint about this is that if no device is present in the
: slot, won't you just get all bits set in whatever you read?  If so,
: the headertype check should be better bounded.

hdrtype would be 0xff.  0xff & 0x7f is 0x7f, which is greater than 2.
What would the problem be?  The only valid header types are 0, 1, and
2 (at least the only ones that we understand).  Technically, if it is
a header type we don't know, we're supposed to disable the device in
the command register too.

Warner