On Tue, Dec 11, 2007 at 11:27:24AM +1100, Benjamin Herrenschmidt wrote: > > The GT-64111 system controller doesn't provide any kind of mapping > > functionality that would help here. So legacy port addressing can only > > work by exploiting aliases due to incomplete decoding of legacy ioport > > addreses by the VT82C586 - but direct addressing is impossible. > > Ok, that explains how the "fix" that we reverted worked. It caused crap > to be added to the top bits of the address :-) > > So here, what you really want to do is not a call to > pcibios_resource_to_bus(), but you actually want to use a different bus > address in the first place, that you know the HW will decode the same > way. > > The best way to achieve that imho, is to do a header quirk that is run > just after the generic probe code, which offsets the fixed legacy > resources by 0x10000000 since that's really the bus address you are > going to emit. > > Later on, your pcibios_fixup code should take that remove 0x10000000 > from all IO resources, since your 0xd0000000 mapping already maps > 0x10000000 as you probably already do. > > The trick is, you don't want to convert a "resource" into a "bus > address" here, but really issue a different bus address.
Oh well, I've cooked up a patch and posted it to linux-mips for testing. Ralf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
