From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B9816524F for ; Tue, 10 Oct 2023 12:25:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RB9t1Xi6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2A470C433C7; Tue, 10 Oct 2023 12:24:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696940705; bh=omFIqKia3wy7Xbwqgl3lEDlQS0jMr0mlUIHVa8ZY/jQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RB9t1Xi6C6UY8MEAUWcmpc14/Xjsaa4NraUXJX6ziZ6S77LJRYcw5jPz1uuO9fARo r+70AQEjYZjsYmbjTpHHdqjp8Q80rxgQpZNdtZkrZKZcaUuCSZhzMFM0MMNJLrc6OO 35nHg0XtxoELdzajsUHQF2HW6wg85SteBC9WdymQikpsZTy+65jjOvwVI54Sdk2amZ Lkqar4AL7Hfzm2z7jAXAIytZOxyGCV9QxKa26KqGzt8mWu84II+BDaG6/plyWnLrtv 7QZeOUeSd0dC8DTMW1o2gSOzVWOCJq+FICgRYyiBeTUz9OvqK6CGJZ9BvKe7kn7HHm aWmLRQoVsbMDg== Date: Tue, 10 Oct 2023 17:54:47 +0530 From: Manivannan Sadhasivam To: Bjorn Andersson Cc: Dmitry Baryshkov , Caleb Connolly , Andy Gross , Bhupesh Sharma , Bjorn Andersson , Konrad Dybcio , Mathieu Poirier , Rob Herring , Krzysztof Kozlowski , Conor Dooley , "Rafael J. Wysocki" , Daniel Lezcano , Amit Kucheria , Zhang Rui , Sibi Sankar , Thara Gopinath , linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org, devicetree@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH 0/4] thermal: Introduce Qualcomm Thermal Mitigation Device support Message-ID: <20231010122447.GJ4884@thinkpad> References: <20230905-caleb-qmi_cooling-v1-0-5aa39d4164a7@linaro.org> <20231001155701.GA53767@thinkpad> <20231002145239.GA12041@thinkpad> <20231002155814.GB12041@thinkpad> <20231002161308.GC12041@thinkpad> <20231005023658.GE3553829@hu-bjorande-lv.qualcomm.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20231005023658.GE3553829@hu-bjorande-lv.qualcomm.com> On Wed, Oct 04, 2023 at 07:36:58PM -0700, Bjorn Andersson wrote: > On Mon, Oct 02, 2023 at 09:43:08PM +0530, Manivannan Sadhasivam wrote: > > On Mon, Oct 02, 2023 at 07:00:27PM +0300, Dmitry Baryshkov wrote: > > > On Mon, 2 Oct 2023 at 18:58, Manivannan Sadhasivam wrote: > > > > > > > > On Mon, Oct 02, 2023 at 06:00:37PM +0300, Dmitry Baryshkov wrote: > > > > > On Mon, 2 Oct 2023 at 17:52, Manivannan Sadhasivam wrote: > > > > > > > > > > > > On Sun, Oct 01, 2023 at 06:26:14PM +0100, Caleb Connolly wrote: > > > > > > > > > > > > > > > > > > > > > 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? > > > > > > > > > > > > Thermal framework expects each thermal zone represented in DT to have atleast > > > > > > one corresponding thermal sensor defined using "thermal-sensors" property. But > > > > > > with TMD, there is no thermal sensor AFAIK. > > > > > > > > > > As far as I understand, no. It is perfectly fine to have 'cooling' > > > > > devices, which react to external thermal monitoring events. I might be > > > > > mistaken, but I think that is the case here, isn't it? > > > > > > > > > > > > > Yes it is represented as cooling device(s). But I do not see any cognizant way > > > > to plug it with thermal zones i.e., unless TMD itself reports temperature of the > > > > modem, using it as a cooling device for external temperature events doesn't > > > > sound good to me. > > > > > > Why? We have compute, q6, wlan tsens sensors. So it seems natural to > > > tell CDSP to slow down if compute sensor reports overheating. > > > > > > > TMD is for external devices such as PCIe modems as well. Is there a temperature > > sensor for that? > > > > According to the schematics for the SC8280XP CRD sys_therm5 would be the > sensor you're looking for. > Hmm, then it seems fine from my end as long we have the correct sensor data to hook up these cooling devices. - Mani > Regards, > Bjorn -- மணிவண்ணன் சதாசிவம்