[PATCH 11/14] arm64: dts: Add initial device tree support for EXYNOS7
Mark Rutland
mark.rutland at arm.com
Thu Aug 28 02:48:46 PDT 2014
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.
[...]
> > + hsi2c_2: hsi2c at 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.
Mark.
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