On Fri, May 23, 2014 at 8:28 AM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
> On Tue, May 20, 2014 at 11:09 PM, Rob Herring <robherring2@xxxxxxxxx> wrote:
>
>> From: Rob Herring <robh@xxxxxxxxxx>
>>
>> The versatile dts is missing any clock data. Add the clocks.
>>
>> It is not clear from the documentation where pclk comes from, so for
>> now it is a dummy clock which is sufficient for things to work.
>
> AFAICT (from experiments and measurements on some boards, during which
> I destroyed some boards) that is actually just the 24MHz clock right off.
>
>> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
>
>> + core-module@10000000 {
>> + compatible = "arm,core-module-versatile";
>> + reg = <0x10000000 0x200>;
>> +
>> + osc24M: oscillator@24M {
>> + #clock-cells = <0>;
>> + compatible = "fixed-clock";
>> + clock-frequency = <24000000>;
>> + };
>
> Please follow the naming convention from the Integrator DTS, I am
> pretty sure this is a chrystal:
>
> /* 24 MHz chrystal on the core module */
> xtal24mhz: xtal24mhz@24M {
> #clock-cells = <0>;
> compatible = "fixed-clock";
> clock-frequency = <24000000>;
> };
I'm not too sure I'm happy about this naming convention (yours or
mine). Following that node names are generic, it should probably be
just clk or clock. The unit address is a bit of an abuse as there is
no reg property, but we do need some way to make it unique. I don't
see the point of having the frequency in the name twice either.
>> + /* OSC1 on AB, OSC4 on PB */
>> + osc1: cm_aux_osc@24M {
>> + #clock-cells = <0>;
>> + compatible = "arm,versatile-cm-auxosc";
>> + clocks = <&osc24M>;
>> + };
>
> Name xtal, also: why is this inside the core module node?
> You're explicitly saying it is on the PB (platform baseboard)
> and *not* on the core module!
But it is not a crystal. It is an output of the clock chip. This
follows what you have for integrator in name and location and it is
part of the AB core-module.
Rob
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