[GPU] Add missing sensors for mac mini m1

[enen92]

Hey @narugit,

Hope you're doing well. Unfortunately while doing xbmc/xbmc#23770 I found out the gpu temperature tests are failing on our CI. The CI runs on mac minis (M1 CPU).
Runtime testing it (smctemp -l) I figure out those must be the two sensors reported by TGPro for the GPU (they are even the only ones starting with Tg). Interesting stuff - the OS only seems to report data to those sensors when the GPU is under load (otherwise it reports 0.0). TGPro, when the GPU doesn't have any load reports a static 30.0ºC which also matches the average temperature of the machine (the overall sensors the app has combined). So this pretty much indicates they are also using the same strategy smctemp is doing but simply use a fallback temperature when there's no data.
When the GPU is under load the temperature match the one reported by TGPro pretty close!

[narugit]

@enen92
I think the modification itself is good.
However, I am sure there are other sensors that start with Tg, but I would like to know how you were able to determine that these two sensors are needed as a know-how to find effective sensors in the future.

• Tg4b
• Tg1b

[enen92]

@enen92 I think the modification itself is good. However, I am sure there are other sensors that start with Tg, but I would like to know how you were able to determine that these two sensors are needed as a know-how to find effective sensors in the future.

• Tg4b
• Tg1b

In this specific machine only those 2 sensors are available and start with Tg. The metodology was quite easy: checking against TgPro. By default those sensors have a 0.0ºC temperature while TgPro shows a constant value of 30ºC (which also matches the average machine temperature the app displays). Once you put some load on the GPU (by using gpu benchmark from the app store or simply running https://www.matthew-x83.com/online/gpu-test.php) the values on those two sensors (as well as tgpro) start to increase and having similar values. Since we don't really know the polling time (and it's not easy to keep both in sync) you'll have to watch smctemp for a while. Stopping the test makes the temperatures go down until 0.0 again (and 30 on tgpro)

[narugit]

@enen92
Thank you for the clear explanation. The steps you provided are excellent know-how to identify the sensors.

[narugit]

LGTM

[enen92]

Thanks for the merge @narugit. If not asking for too much mins tagging a new version?
Reason is the Mac mini is precisely the Mac version mostly used for media center applications :)

[narugit]

@enen92
Here is it :)
https://github.com/narugit/smctemp/releases/tag/0.2.1