On Sat, 2010-12-11 at 18:06 +0200, Gleb Natapov wrote:
http://playground.sun.com/pub/p1275/bindings/pci/pci2_1.pdf has table on page 10 that defines how pci class code should be translated into OF name. This is what my patch is using. pci-ata does not look spec compliant (or is there more up-to-date spec?)
What should we dowith
ata-2@600 vs drive@1?
There is no available IDE OF binding spec, so I when with the way OpenBIOS reports ata on qemu-x86. I have no idea what 600 in ata-2@600 may mean, but looking at g3_beige_300.html there is no such node there and looking at any other device tree in http://penguinppc.org/historical/dev-trees-html/
Those are old and I wouldn't look too closely at what Apple does.
ATA doesn't really need anything complex, mostly the ata controller, generally named "ata" nowadays with a #address-cells of 1 and a #size-cells of 0. Children are then typically disk, cdrom, ... (ie block devices) with a unit address of 0 for master and 1 for slave.
In the case of controllers with multiple ports, typically you have one such "ata" node per bus. "pci-ata" is a liberal use by Apple here representing the actual host controller PCI device.
In any case, what matters is the "compatible" property. This is what defines the programming interface of a device.
I haven't found one that use this kind of addressing for pci-ata. http://penguinppc.org/historical/dev-trees-html/g3bw_400.html for instance has pci@80000000/pci-bridge@d/pci-ata@1/ata-4. ata-2@600 kind of addressing is used by devices on mac-io bus which I do not think we emulate in qemu. So it looks like OpneBIOS is wrong here.
Well, it's possible that the @600 represents a register offset within pci-ata, this is entirely up to pci-ata to do as it wishes there to define it's own internal binding. Is there a "ranges" property defining translation accross "pci-ata" ?
Cheers, Ben.