Re: [PATCH V4 12/16] Documentation: DT: bindings: Add power domain info for NVIDIA PMC

From: Jon Hunter
Date: Fri Jan 15 2016 - 04:43:17 EST



On 14/01/16 14:41, Thierry Reding wrote:
> * PGP Signed by an unknown key
>
> On Fri, Dec 04, 2015 at 02:57:13PM +0000, Jon Hunter wrote:
>> Add power-domain binding documentation for the NVIDIA PMC driver in
>> order to support generic power-domains.
>>
>> Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
>>
>> ---
>>
>> Please note that I have been debating whether I add this
>> "nvidia,powergate-clock-disable" property or just leave the clocks
>> disabled by default. Some downstream kernels leave the clocks enabled
>> for the audio power-domain because the clocks required for powering up
>> the power-domain are needed by all modules within the power-domain.
>> However are the same time there are other power-domains that may need
>> to be on, but not always clocked and so having the ability to specify if
>> the clocks should be disabled seems useful. However, I can also remove
>> this and just have the appropriate devices turn on the clocks as well.
>> ---
>> .../bindings/arm/tegra/nvidia,tegra20-pmc.txt | 61 ++++++++++++++++++++++
>> 1 file changed, 61 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
>> index 838e1a69ec0a..8e4641db51a9 100644
>> --- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
>> +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
>> @@ -1,5 +1,7 @@
>> NVIDIA Tegra Power Management Controller (PMC)
>>
>> +== Power Management Controller Node ==
>> +
>> The PMC block interacts with an external Power Management Unit. The PMC
>> mostly controls the entry and exit of the system from different sleep
>> modes. It provides power-gating controllers for SoC and CPU power-islands.
>> @@ -69,6 +71,10 @@ Optional properties for hardware-triggered thermal reset (inside 'i2c-thermtrip'
>> Defaults to 0. Valid values are described in section 12.5.2
>> "Pinmux Support" of the Tegra4 Technical Reference Manual.
>>
>> +Optional nodes:
>> +- pm-domains : This node contains a hierarchy of PM domain nodes, which should
>> + match the power-domains on the Tegra SoC.
>> +
>
> pm-domains is a linuxism. Perhaps name this after what Tegra calls this:
> "powergates"?

Ok.

Jon