On 19/08/13 14:02, Rob Herring wrote: > On 08/19/2013 05:19 AM, Mark Rutland wrote: >> On Sat, Aug 17, 2013 at 11:09:36PM +0100, Benjamin Herrenschmidt wrote: >>> On Sat, 2013-08-17 at 12:50 +0200, Tomasz Figa wrote: >>>> I wonder how would this handle uniprocessor ARM (pre-v7) cores, for >>>> which >>>> the updated bindings[1] define #address-cells = <0> and so no reg >>>> property. >>>> >>>> [1] - http://thread.gmane.org/gmane.linux.ports.arm.kernel/260795 >>> >>> Why did you do that in the binding ? That sounds like looking to create >>> problems ... >>> >>> Traditionally, UP setups just used "0" as the "reg" property on other >>> architectures, why do differently ? >> >> The decision was taken because we defined our reg property to refer to >> the MPIDR register's Aff{2,1,0} bitfields, and on UP cores before v7 >> there's no MPIDR register at all. Given there can only be a single CPU >> in that case, describing a register that wasn't present didn't seem >> necessary or helpful. > > What exactly reg represents is up to the binding definition, but it > still should be present IMO. I don't see any issue with it being > different for pre-v7. > Yes it's better to have 'reg' with value 0 than not having it. Otherwise this generic of_get_cpu_node implementation would need some _hack_ to handle that case. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
