On Thu, Dec 06, 2007 at 12:32:54PM +0000, Ralf Baechle wrote: > > > What I don't understand is thus why you are calling resource_to_bus on > > > 0x1f0 > > > which is -not- a resource value, but is already a BAR value... > > > > 0x1f0 is resource value on MIPS Cobalt. > > All RAW BAR values contain the offset(0x10000000) on it. > > In arch/mips/cobalt/pci.c: > > static struct resource cobalt_io_resource = { > .start = 0x1000, > .end = GT_DEF_PCI0_IO_SIZE - 1, > .name = "PCI I/O", > .flags = IORESOURCE_IO, > }; > > static struct pci_controller cobalt_pci_controller = { > [...] > .io_resource = &cobalt_io_resource, > .io_offset = 0 - GT_DEF_PCI0_IO_BASE, > }; > > The .io_offset initialization looks odd; no other platform is trying to > use a negative offset here. I think there was something odd with the > Galileo GT-64111 which (unlike its later sucessors such as the GT-64120) > passes memory accesses in the range 0x10000000 ... 0x11ffffff to the PCI > bus unmodified. That is for example a load or store to physical address > 0x100003f8 will become an I/O port access to 0x100003f8. > > I hope this is just a missconfiguration of the GT-64111, time for manual > reading.
The GT-64120 has remapping register which the GT-64111 is lacking. So the way things are I don't see how it would be possibly to generate an I/O port address below GT_DEF_PCI0_IO_BASE (0x10000000) on that system controller. Which of course mean any sort of device that requires legacy I/O port addressing is out of question unless one intentionally (ab-)uses aliases due to only partial decoding of the I/O port address. Which would mean no chance of using legacy I/O port devices with the Galileo. There must be something I'm missing here, I just can't believe somebody could possibly design such a lunatic system controller. 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/