Re: [PATCH v3] thermal: core: Call monitor_thermal_zone() if zone temperature is invalid

[Stefan Lippers-Hollmann <s.l-h@gmx.de>]

Hi

On 2024-07-16, Rafael J. Wysocki wrote:
> On Tue, Jul 16, 2024 at 1:36 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
> > On Tue, Jul 16, 2024 at 1:15 PM Stefan Lippers-Hollmann <s.l-h@gmx.de> wrote:
> > > On 2024-07-16, Stefan Lippers-Hollmann wrote:
> > > > On 2024-07-16, Rafael J. Wysocki wrote:
> > > > > On Tue, Jul 16, 2024 at 1:48 AM Stefan Lippers-Hollmann <s.l-h@gmx.de> wrote:
> > > > > > On 2024-07-15, Rafael J. Wysocki wrote:
> > > > > > > On Mon, Jul 15, 2024 at 2:54 PM Stefan Lippers-Hollmann <s.l-h@gmx.de> wrote:
> > > > > > > > On 2024-07-15, Rafael J. Wysocki wrote:
> > > > > > > > > On Mon, Jul 15, 2024 at 11:09 AM Daniel Lezcano
> > > > > > > > > <daniel.lezcano@linaro.org> wrote:
> > > > > > > > > > On 15/07/2024 06:45, Eric Biggers wrote:
> > > > > > > > > > > On Thu, Jul 04, 2024 at 01:46:26PM +0200, Rafael J. Wysocki wrote:
> > > > > > > > > > >> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > > > > > [...]
> > > > > > > > Silencing the warnings is already a big improvement - and that patch
> > > > > > > > works to this extent for me with an ax200, thanks.
> > > > > > >
> > > > > > > So attached is a patch that should avoid enabling the thermal zone
> > > > > > > when it is not ready for use in the first place, so it should address
> > > > > > > both the message and the useless polling.
> > > > > > >
> > > > > > > I would appreciate giving it a go (please note that it hasn't received
> > > > > > > much testing so far, though).
> > > > > >
> > > > > > Sadly this patch doesn't seem to help:
> > > > >
> > > > > This is likely because it is missing checks for firmware image type.
> > > > > I've added them to the attached new version.  Please try it.
> > > > >
> > > > > I've also added two pr_info() messages to get a better idea of what's
> > > > > going on, so please grep dmesg for "Thermal zone not ready" and
> > > > > "Enabling thermal zone".
> > > >
> > > > This is the output with the patch applied:
> > >
> > > The ax200 wlan interface is currently not up/ configured (system
> > > using its wired ethernet cards instead), the thermal_zone1 stops
> > > if I manually enable the interface (ip link set dev wlp4s0 up)
> > > after booting up:
> >
> > This explains it, thanks!
> >
> > The enabling of the thermal zone in iwl_mvm_load_ucode_wait_alive() is
> > premature or it should get disabled in the other two places that clear
> > the IWL_MVM_STATUS_FIRMWARE_RUNNING bit.
> >
> > I'm not sure why the thermal zone depends on whether or not this bit
> > is set, though. Is it really a good idea to return errors from it if
> > the interface is not up?
[...]
> > > [   22.033468] thermal thermal_zone1: failed to read out thermal zone (-61)
> > > [   22.213120] thermal thermal_zone1: Enabling thermal zone
> > > [   22.283954] iwlwifi 0000:04:00.0: Registered PHC clock: iwlwifi-PTP, with index: 0
> >
> > Thanks for this data point!
> >
> > AFAICS the thermal zone in iwlwifi is always enabled, but only valid
> > if the interface is up.  It looks to me like the thermal core needs a
> > special "don't poll me" error code to be returned in such cases.
>
> Attached is a thermal core patch with an iwlwifi piece along the lines
> above (tested lightly).  It adds a way for a driver to indicate that
> temperature cannot be provided at the moment, but that's OK and the
> core need not worry about that.
>
> Please give it a go.

This seems to fail to build on top of v6.10, should I test Linus' HEAD
or some staging tree instead?

[ I will be offline for the next few hours now, but will test it as soon
  as possible, probably in ~9-10 hours ]

  CC      drivers/thermal/thermal_core.o
drivers/thermal/thermal_core.c: In function 'handle_thermal_trip':
drivers/thermal/thermal_core.c:383:37: error: 'THERMAL_TEMP_INIT' undeclared (first use in this function); did you mean 'THERMAL_TEMP_INVALID'?
  383 |             tz->last_temperature != THERMAL_TEMP_INIT) {
      |                                     ^~~~~~~~~~~~~~~~~
      |                                     THERMAL_TEMP_INVALID
drivers/thermal/thermal_core.c:383:37: note: each undeclared identifier is reported only once for each function it appears in
drivers/thermal/thermal_core.c: In function 'thermal_zone_device_init':
drivers/thermal/thermal_core.c:432:27: error: 'THERMAL_TEMP_INIT' undeclared (first use in this function); did you mean 'THERMAL_TEMP_INVALID'?
  432 |         tz->temperature = THERMAL_TEMP_INIT;
      |                           ^~~~~~~~~~~~~~~~~
      |                           THERMAL_TEMP_INVALID

Regards
	Stefan Lippers-Hollmann