Re: [PATCH v4 6/8] arm64: dts: add SRAM, MHU mailbox and SCPI support on Juno

[Sudeep Holla]

On 08/06/15 14:51, Jon Medhurst (Tixy) wrote:
> On Mon, 2015-06-08 at 11:40 +0100, Sudeep Holla wrote:
> [...]
> > +
> > +	scpi {
> > +		compatible = "arm,scpi";
> > +		mboxes = <&mailbox 1>;
> > +		shmem = <&cpu_scp_hpri>;
> > +
> > +		clocks {
> > +			compatible = "arm,scpi-clocks";
> > +
> > +			scpi_dvfs: scpi_clocks@0 {
> > +				compatible = "arm,scpi-dvfs-clocks";
> > +				#clock-cells = <1>;
> > +				clock-indices = <0>, <1>, <2>;
> > +				clock-output-names = "vbig", "vlittle", "vgpu";
>
>  From where do the clock names derive? They look more like names for
> voltage domains rather than clocks. My (admittedly very old) Juno docs,
> have the clocks as ATLCLK, APLCLK and GPUCLK.

I agree, I just copied it from SCPI spec which just deals with power
domain names in the context of DVFS. I will update as per Juno doc.

> > +			};
> > +			scpi_clk: scpi_clocks@3 {
> > +				compatible = "arm,scpi-variable-clocks";
> > +				#clock-cells = <1>;
> > +				clock-indices = <3>, <4>;
> > +				clock-output-names = "pxlclk0", "pxlclk1";
>
> Can we also have clock index 5, name 'i2s_clk', for used by audio?
> (I don't know what other clocks the SCP currently supports, but audio is
> one being currently used by the out-of-tree code).

I will update.

> Also, I believe that both display outputs share the same clock, and so
> pxlclk0 and pxlclk1 can't be controlled independently. But I guess these
> device-tree entries are for the interface to the SCP firmware, not the
> hardware, and if that pretends the clocks are independent...

Yes, this is bit tricky, I will let Liviu answer this.

Regards,
Sudeep
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