On Thu, Aug 28, 2014 at 2:48 AM, Mark Rutland <mark.rutland@xxxxxxx> wrote:
> Hi,
>
>> > + cpus {
>> > + #address-cells = <2>;
>> > + #size-cells = <0>;
>>
>> Why size-cells=2? Can you not fit a cpuid in 32 bits?
>
> As of commit 72aea393a2e7 (arm64: smp: honour #address-size when parsing
> CPU reg property) Linux can handle single-cell cpu node reg entries
> where /cpus/#address-cells = <1>.
>
> I can't make any guarantees about other code (e.g. bootloaders) which
> might try to do things with cpu nodes, YMMV.
Ok. If address-cells is kept at 2 the unit address needs to be changed
to "0,0". So one or the other has to be changed.
> [...]
>
>> > + hsi2c_2: hsi2c@14E60000 {
>>
>> I much prefer lowercase hex in unit addresses (and reg entries) below. I
>> know 32-bit uses uppercase, but let's switch going forward here.
>
> My preference also; I'm happy to enforce that on new dts.
>
> [...]
>
>> > + timer {
>> > + compatible = "arm,armv8-timer";
>> > + interrupts = <1 13 0xff01>,
>> > + <1 14 0xff01>,
>> > + <1 11 0xff01>,
>> > + <1 10 0xff01>;
>> > + clock-frequency = <24000000>;
>> > + use-clocksource-only;
>> > + use-physical-timer;
>>
>> These two properties are not standard, and I would expect any 64-bit
>> platform to come with PSCI such that you have a way to initialize the
>> virtual timers.
>
> Likewise with clock-frequency. It's not a full workaround, and it's not
> hard to initialise CNTFRQ on each CPU.
Technically clock-frequency is documented, but not recommended to be
used unless needed for working around firmware that doesn't setup the
register value. :)
In this case it's likely a cargo cult carry over from 5250 where the
CNTFRQ requirement happened around the same time as we were working on
it so that generation firmware lacked support for it -- it should
since then have been fixed properly.
-Olof
--
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
