Re: [PATCH V3 1/2] Documentation: DT: Add binding documentation for NVIDIA ADMA

From: Jon Hunter
Date: Mon Oct 19 2015 - 07:23:06 EST



On 16/10/15 17:09, Stephen Warren wrote:
> On 10/16/2015 01:35 AM, Jon Hunter wrote:
>> Add device-tree binding documentation for the Tegra210 Audio DMA
>> controller.
>
>> diff --git a/Documentation/devicetree/bindings/dma/tegra210-adma.txt
>> b/Documentation/devicetree/bindings/dma/tegra210-adma.txt
>
>> +Required properties:
>
>> +- interrupt-parent: Phandle to the interrupt parent controller.
>
> Nit: Since that is more of a "system level"/standard property, it's
> typical not to document it. The property is not actually required if the
> inherited value is already correct. Still, it's obvious enough what this
> means, so I'd only suggest fixing this if you have to respin for some
> other reason.

Ok.

>> +- clocks: Must contain one entry for the ADMA module clock, "adma_ape".
>> +- clock-names: Must contain the entry "adma_ape".
>
> Which clock is this in the CAR? I don't see any adma_ape clock
> documented in the TRM.

Darn. I thought I had checked this. Yes it should be the AHUB clock and
looking at the current t210 clock patches for mainline this is
TEGRA210_CLK_D_AUDIO. Ok will fix this.

> Is there a dedicated reset signal for this module? If so, we should
> require a resets property.

No there does not appear to be. Looking at the documentation the ADMA
would be reset by the main APE reset. Seems to be one reset that resets
most modules in the APE.

That raises another issue, the ADMA is in the audio power partition and
currently our downstream driver assumes that this is on. I should at
least check this.

Jon
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