Messages in this thread | | | Date | Fri, 16 Jul 1999 00:40:54 -0700 | From | David Hinds <> | Subject | Re: New kernel/resource.c |
| |
On Thu, Jul 15, 1999 at 10:27:17PM -0700, Linus Torvalds wrote: > > On Thu, 15 Jul 1999, David Hinds wrote: > > > > You've lost me again. inb/outb and readb/writeb are not PCI specific, > > so how can they be arbitrated using a PCI-specific resource tree? > > They ARE PCI specific. > > What's the problem?
I've still got a laptop on my desk that doesn't have a PCI bus. As far as I can tell, all its drivers use inb/outb and readb/writeb in exactly the same way as they are used on another laptop on my desk that does have a PCI bus. I'm not trying to be obtuse here: I really don't understand what you're trying to say.
Glancing through the kernel tree, use of inb()/outb() seems to be fairly common on platforms that do not have PCI busses. On some platforms, addresses obtained from ioremap() are dereferenced without using read[bwl] but I don't know if this is kosher or not, as there is little documentation of such things.
On my PCI-based laptop, there are also a dozen or so devices that reside behind a PCI-to-ISA bus bridge. They are accessed using inb/outb and readb/writeb. It isn't clear to me where their resources should go, if you want separate resource trees for each bus. They are not PCI devices, but they clearly occupy the same flat address space as real PCI devices.
-- Dave Hinds
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |