Re: [PATCH 0/4] thermal: Introduce Qualcomm Thermal Mitigation Device support

[Caleb Connolly <caleb.connolly@linaro.org>]

On 01/10/2023 16:57, Manivannan Sadhasivam wrote:
> On Fri, Sep 29, 2023 at 05:16:16PM +0100, Caleb Connolly wrote:
>> The Thermal Mitigation Device (TMD) Service is a QMI service that runs
>> on remote subsystems (the modem and DSPs) on Qualcomm SoCs.
>> It exposes various mitigations including passive thermal controls and
>> rail voltage restrictions.
>>
>> This series introduces support for exposing TMDs as cooling devices
>> in the kernel through the thermal framework, using the QMI interface.
>>
>> Each TMD client is described as a child of the remoteproc node in
>> devicetree. With subnodes for each control.
>>
> 
> Daniel expressed concerns in the past aganist representing TMD driver as a
> cooling device since it is not tied to thermal zones and the governors cannot
> use it. Instead he suggested to represent it as a powercap device with thermal
> constraints.

Hi Mani,

Forgive me as I'm not yet super familiar with the thermal subsystem.

As I understand it, the DT layout here enables each control to be 
referenced under the thermal zones, at least this is the approach taken 
in CAF 4.9.

Maybe I don't quite understand what you mean, are you saying that using 
thermal zones is the wrong approach?
> 
> So please look into that approach.

Any recommended reading? Or drivers I can use as a reference?

Thanks
> 
> - Mani
> 
>> This series is based on previous work by Bhupesh Sharma which can be
>> found at [1]. I'm sending this as a fresh series as it has been a
>> year since the original version and I have rewritten most of the driver.
>>
>> [1]: https://lore.kernel.org/linux-arm-msm/20220912085049.3517140-1-bhupesh.sharma@linaro.org/
>>
>> ---
>> Caleb Connolly (4):
>>        remoteproc: qcom: probe all child devices
>>        dt-bindings: thermal: Add qcom,qmi-cooling yaml bindings
>>        thermal: qcom: add qmi-cooling driver
>>        MAINTAINERS: Add entry for Qualcomm Cooling Driver
>>
>>   .../bindings/remoteproc/qcom,msm8996-mss-pil.yaml  |  13 +
>>   .../bindings/remoteproc/qcom,pas-common.yaml       |   6 +
>>   .../bindings/thermal/qcom,qmi-cooling.yaml         | 168 +++++++
>>   MAINTAINERS                                        |   8 +
>>   drivers/remoteproc/qcom_q6v5.c                     |   4 +
>>   drivers/remoteproc/qcom_q6v5_mss.c                 |   8 -
>>   drivers/thermal/qcom/Kconfig                       |  13 +
>>   drivers/thermal/qcom/Makefile                      |   1 +
>>   drivers/thermal/qcom/qmi-cooling.c                 | 520 +++++++++++++++++++++
>>   drivers/thermal/qcom/qmi-cooling.h                 | 428 +++++++++++++++++
>>   10 files changed, 1161 insertions(+), 8 deletions(-)
>> ---
>> base-commit: 9067f80db58bbce81d5f0703aa2fd261e88bc812
>>
>> // Caleb (they/them)
>>
> 

-- 
// Caleb (they/them)