Le Mon, Nov 18, 2024 at 01:01:11AM +0100, Tobias Heider a écrit :
> Here is the promised diff to get scmi for cpu frequency management
> working on the Snapdragon X Elite.  Roughly speaking this adds two
> big new features: mailbox transport and the scmi perf protocol.
> 
> Mailbox transport is very similar to smc which we already support.
> Messages are written to a shared memory region, instead of an SMC call we
> use a mailbox doorbell to notify the platform that our request is ready.
> On X Elites this is done using the CPUCP mailbox which we support via
> qccpucp(4). The attach function for the mbox transport is deferred to make
> sure our mailbox driver is available when we need it.
> There are a lot of possible optimization here, instead of polling we could
> use mailbox interrupts and for PERFORMANCE_LEVEL_GET we probably want to
> switch to using a fast channel at some point.
> 
> The perf protocol allows us to read and set the performance level of our
> performance domains. On the X Elite we have 3 domains, each spanning 4 cpu
> cores. This patch adds sensors to expose the current frequency and power
> consumption for each domain. It is a bit pointless since the level doesn't
> really change currently. Eventually we probably want to hook this up to
> cpu(4) to expose it to apm(8).
> 
> The output on my T14s looks like this:
> $ sysctl | grep scmi                                                   
> hw.sensors.scmi0.power0=0.22 W
> hw.sensors.scmi0.power1=0.29 W
> hw.sensors.scmi0.power2=0.31 W
> hw.sensors.scmi0.frequency0=2976000000.00 Hz
> hw.sensors.scmi0.frequency1=3417600000.00 Hz
> hw.sensors.scmi0.frequency2=3417600000.00 Hz
> 
> Test feedback and reviews welcome. I don't have a machine using scmi-smc or
> the clock protocol so I'd appreciate if someone could test those too.

on the omnibook x14 i get this difference in dmesg:

-"scmi" at mainbus0 not configured
+scmi0 at mainbus0
...
+scmi0: no tx mbox

and no hw.sensors.scmi0.

where should i look to figure out what to change ?