Re: [PATCH 2/3] dt-bindings: amlogic: Add Internal Clock Measurer bindings

From: Neil Armstrong
Date: Tue Jul 17 2018 - 07:30:45 EST


Hi Rob,

On 16/07/2018 23:45, Rob Herring wrote:
> On Tue, Jul 03, 2018 at 03:21:49PM +0200, Neil Armstrong wrote:
>> The Amlogic Meson GX SoCs embeds a clock measurer IP to measure the internal
>> clock paths frequencies.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/soc/amlogic/clk-measure.txt | 15 +++++++++++++++
>> 1 file changed, 15 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/soc/amlogic/clk-measure.txt
>>
>> diff --git a/Documentation/devicetree/bindings/soc/amlogic/clk-measure.txt b/Documentation/devicetree/bindings/soc/amlogic/clk-measure.txt
>> new file mode 100644
>> index 0000000..ba9183a
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/soc/amlogic/clk-measure.txt
>> @@ -0,0 +1,15 @@
>> +Amlogic Internal Clock Measurer
>> +===============================
>> +
>> +The Amlogic SoCs contains an IP to measure the internal clocks.
>> +The precision is multiple of MHz, useful to debug the clock states.
>
> What a simple yet useful debug tool.
>
>> +
>> +Required properties:
>> +- compatible: Shall contain "amlogic,meson-gx-clk-measure"
>> +- reg: base address and size of the Clock Measurer register space.
>> +
>> +Example:
>> + clock-measure@8758 {
>> + compatible = "amlogic,meson-gx-clk-measure";
>> + reg = <0x0 0x8758 0x0 0x10>;
>
> This doesn't really look like its own block though. Can't the parent
> device instantiate the driver for this?

As weird as it seems, on the GX family the registers are not on a aligned boundary, but yes it's its own block.
On newer SoCs, they have a more aligned register address, with the exact same register set.

Neil

>
>
>> + };
>> --
>> 2.7.4
>>
>>
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