[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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