From mboxrd@z Thu Jan 1 00:00:00 1970 From: mperttunen@nvidia.com (Mikko Perttunen) Date: Wed, 13 Aug 2014 13:59:00 +0300 Subject: [PATCH 0/3] Thermal reset support in PMC In-Reply-To: <20140813105354.GA4843@ulmo> References: <1407226380-747-1-git-send-email-mperttunen@nvidia.com> <20140813080744.GD7735@ulmo> <53EB1DF5.301@nvidia.com> <53EB250D.5070207@nvidia.com> <20140813085728.GF7735@ulmo> <53EB3556.9010504@nvidia.com> <20140813103613.GA7624@ulmo> <53EB40F0.4000300@nvidia.com> <20140813105354.GA4843@ulmo> Message-ID: <53EB44F4.6090808@nvidia.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 13/08/14 13:53, Thierry Reding wrote: > * PGP Signed by an unknown key > > On Wed, Aug 13, 2014 at 01:41:52PM +0300, Mikko Perttunen wrote: >> >> >> On 13/08/14 13:36, Thierry Reding wrote: >>>> Old Signed by an unknown key >>> >>> On Wed, Aug 13, 2014 at 12:52:22PM +0300, Mikko Perttunen wrote: >>>> On 13/08/14 11:57, Thierry Reding wrote: >>>>>> Old Signed by an unknown key >>>>> >>>>> On Wed, Aug 13, 2014 at 11:42:53AM +0300, Mikko Perttunen wrote: >>>>>> >>>>>> >>>>>> On 13/08/14 11:12, Mikko Perttunen wrote: >>>>>>> On 13/08/14 11:07, Thierry Reding wrote: >>>>>>>>> Old Signed by an unknown key >>>>>>>> >>>>>>>> On Tue, Aug 05, 2014 at 11:12:57AM +0300, Mikko Perttunen wrote: >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> this series adds support for hardware-triggered thermal reset to the PMC >>>>>>>>> driver. Namely, it adds device tree properties for specifying the I2C >>>>>>>>> command to be sent when thermtrip is triggered. It is to be noted >>>>>>>>> that thermtrip won't be ever triggered without a soctherm driver to >>>>>>>>> calibrate the sensors, but I'll follow up with that patch. >>>>>>>>> >>>>>>>>> pmc.c required some juggling around to make the match data usable in >>>>>>>>> probe, since I didn't want to put the code into the initcall either, since >>>>>>>>> the soctherm driver won't be initialized by that point anyway. >>>>>>>>> >>>>>>>>> Series tested on Jetson-TK1. Should work on Tegra30 and Tegra114 too. >>>>>>>> >>>>>>>> Can you describe the procedure used to test this? We currently have a >>>>>>>> bunch of features in Tegra that some people have tested at some point >>>>>>>> during development but the test procedures never got documented. That >>>>>>>> means whenever we want to test something we need to go and reinvent a >>>>>>>> bunch of tests after the fact. >>>>>>>> >>>>>>>> So what I'd like to start doing is collect tests (preferably in some >>>>>>>> scripted way) so that they can be kept in a repository that people can >>>>>>>> easily clone and run on devices. >>>>>>>> >>>>>>>> Could you provide something like that for thermtrip? >>>>>>> >>>>>>> Sure. I'll see if I can make a just a test script or if a local patch is >>>>>>> needed to test. Btw, I also have a pretty nice test script for EMC >>>>>>> ready, and I agree that such a repository would be very nice. >>>>>> >>>>>> Here is a test program. It it works, the device with immediately shut down. >>>>>> >>>>>> https://gist.github.com/cyndis/66126c9c176b5f94a76f >>>>> >>>>> Is there a way to set the trip temperature without going through >>>>> /dev/mem? I'd expect the device to have a sysfs interface of some >>>>> sort. >>>> >>>> The thermtrip "device" isn't currently exposed in any way. If it were >>>> exposed, I suppose it would be exposed as thermal zone devices, each with >>>> one trip point. Even then, the thermal framework doesn't really support this >>>> properly; none of the trip point types really apply to this kind of trip >>>> point, and x86 systems don't expose their trips either. >>> >>> Okay. The reason why I asked is because I'm not sure yet that having C >>> programs in the test suite would be good, so having something that's >>> easily scriptable would be preferred. >> >> I agree. Looks like Python's stdlib has mmap support, so maybe we could use >> that. > > Yes, possibly. It still means that somebody needs to have some kind of > advanced scripting available to test this. While having a testsuite is > useful, it would still be nice to occasionally be able to test things > with just simple shell commands. > >>>> Anyway, since debugging is pretty much the only use case for modifying >>>> the trip temperature, I thought adding the tz_devices would be a bit >>>> overkill. >>> >>> An alternative could be a file in debugfs. >> >> True, though there's the "don't expose dangerous stuff in debugfs" argument >> against that. I don't really have problem with it, though. >> Although in this case I think the script approach would be good enough. > > I've said this before and I don't think "dangerous stuff in debugfs" is > a valid argument. You need superuser privileges to access debugfs, and > if you have such privileges you can do pretty much what you want (run > the test program you posted for example). I agree with you completely. I guess I can add a debugfs entry to the soctherm driver, probably in a separate patch once the original series is in. It is then up to the thermal maintainers whether they agree with us or not. > > Thierry > > * Unknown Key > * 0x7F3EB3A1 >