In message: <[email protected]> John Baldwin <[email protected]> writes: : On Tuesday, August 24, 2010 12:09:45 am M. Warner Losh wrote: : > In message: <[email protected]> : > John Baldwin <[email protected]> writes: : > : > So more or less it's for BIOSes with ISA that doesn't feature plug : > : > and play (286s, 386s, some 486s?)? Just trying to fill in the gap :). : > : : > : Yes, it may perhaps still be useful for some x86 embedded systems, though : > : it is doubtful that those would use a ppc(4) device perhaps. : > : > Many embedded x86 systems use ppc(4) as a DIO port. ppi attaches to : > it and can be used to frob bits. : > : > These days, of course, almost all boards have ACPI, so that means they : > get enumerated that way. Only boards that don't run windows might not : > have ACPI, in which case the devices are usually enumerated via : > PNPBIOS. But not always, since those boards tend to have the buggiest : > BIOSes on the planet in this area. Hints are needed on a few of these : > boards since nothing else will work. And they have Atom processors on : > them... : : The specific code I am referring to is the code in ppc_isa_probe() that tries : to auto-identify a ppc port by poking at various I/O ports directly. It is : not enabled by default. You'd have to have a ppc hint that did not include an : I/O port for this code to be triggered I think as it only gets executed if a : ppc(4) device does not have an I/O port resource from ACPI/PnPBIOS/hints.
Ah, that code... Yes, you're right... : I was mostly thinking of this in terms of ISA cards, and I doubt that even : modern embedded systems have ISA slots. :) There are still a few PC-104 boards knocking around (which is ISA in a different form-factor), but mostly people have moved PC-104+ which is really PCI or other things... Warner _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "[email protected]"
