Subject: Re: looking for devices on PCI bus
To: None <jonathan@DSG.Stanford.EDU, wrstuden@zembu.com>
From: None <eeh@netbsd.org>
List: tech-kern
Date: 05/03/2001 00:56:28
	I am definitly talking just about PCI. I'm not sure how to expand these
	ideas to other direct connect busses. Do say TURBOchannel or VME or SBus
	support hot-swap? I think I'm talking about duplicating less of the PCI
	machinery than you think I am. :-)

SBus slots may not but entire SBuses can be hotswapped.  These are not
PCI-specific issues and should be generalized.  However, some aspects
of hotswap, such as detection and probing/reprobing are bus-specific.

	> I am suggesting that if we need to go scan everything *anyway*, why
	> *bother* keeping the locators/match arguments around? Just keep track
	> of which devices have already been grabbed by drivers, using an extent
	> map for some unique attribute (for PCI, header block address, maybe?).

	A map of which devices have been grabbed would work. But it doesn't help
	as much with the, "there but unconfigured" case.

Since the device could be replaced, there's no point in keeping information
about the "there but unconfigured" case.

Eduard