On Fri, Jan 6, 2012 at 3:24 PM, Mitch Bradley <w...@firmworks.com> wrote: > On 1/6/2012 12:09 PM, Grant Likely wrote: >> >> On Thu, Jan 05, 2012 at 08:39:50PM -0800, Olof Johansson wrote: >>> >>> Hi, >>> >>> I'm considering how to best describe the data that ramoops needs in >>> the device tree. >>> >>> The idea is really about describing a memory area that is (likely to >>> be) nonvolatile across reboots. Said area is not to be included in the >>> regular memory map of the system (i.e. not covered by /memory). >>> >>> I have a few options on where to do it. It's not really a hardware >>> device per se, so it's a gray area for the device tree alltogether. >>> >>> How about something like? >>> >>> compatible = "linux,ramoops" >>> linux,ramoops-start =<start address of preserved ram> >>> linux,ramoops-size = ... >> >> >> I'm not a fan of using separate start& size properties. I'd rather >> >> see a 'reg' type property like "linux,ramoops-mem =<start size>;", >> but doing it in separate properties does may early boot code easier to >> write. I assume that is why the initrd start and size values are >> passed separately. > > > Separate properties admit the possibility of errors where one is present but > not the other. I prefer atomicity. It's either there, with all the > information, or it isn't.
.... I was /going/ to argue that having a single property requires parsing #{address,size}-cells whereas passing separately does not... but thinking about it more that isn't actually true (although the cells size could be inferred when using separate properties). So, yes, I agree with Mitch. A single property is better. g. _______________________________________________ devicetree-discuss mailing list devicetree-discuss@lists.ozlabs.org https://lists.ozlabs.org/listinfo/devicetree-discuss