On Mon, 2010-11-29 at 20:36 +0100, Sebastian Andrzej Siewior wrote: > > This also works with the flat tree, right?
Yes, of course. You use similar references in your interrupt-map :-) > Okay, so we want this for a quirk at a later point in time. Now I > understand. More precisely, if something has to depend on a specific revision/errata/feature, in the future, it would be problematic to have to modify the device-tree. The "rule" for compatible is to be a list going from a reasonably precise description of the specific device to the more generic programming interface the device implements. > Would "isa-bridge" be acceptable? So I don't have to add a new bus to > the probe list for every new SoC. Just call it 'isa', as for device_type, we shouldn't need it. The default "probe list" is crap. If you want to have platform devices instanciated for the ISA devices from the device-tree, I'd rather you explicitely do it from the architecture code. As Scott said, "isa" doesn't quite qualify as a "generic" simple bus. > Yes. of_address_to_resource() will do the right thing in this case. It > can only be used after unflatten_device_tree() and I need this > earlier. This probably means you are doing the unflattening too late... > Now using unflatten_device_tree() earlier isn't that easy, or is it. > I defered the ioapic init a little, so it is now called from > x86_init.mpparse.get_smp_config() so I have alloc_bootmem() working. You can probably do the unflattening way before alloc_bootmem is available. The unflattening does a first pass to scan for the size, so all you need is a way to get a single contiguous chunk of memory, I'm sure x86 has ways to provide that sort of thing really early before bootmem is initialized (what about memblock btw ?). > So unflatten_device_tree() seems to work here. The ugly part comes > now: > early_init_dt_alloc_memory_arch() expects u64 which works with > phys_to_virt() and the other way around. This isn't really the case > with > what __alloc_bootmem(). This looks like phys_map to me. Since the dtb > code > simply uses phys_to_virt() it doesn't really matter. So it works and > I > probably can use of_address_to_resource(). Yeah just __pa what alloc_bootmem returns but as I said, it should probably be unflattened earlier than that. Peter (CC) should be able to help finding the right spot/API there. Cheers, Ben. > > Cheers, > > Ben. > > Sebastian > -- > 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/ _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
