PC Processors

[danielmgessel]

The current hwmon driver for Zen 3 cores appears to be https://github.com/torvalds/linux/blob/master/drivers/hwmon/k10temp.c which, on my Dell Inspiron 5625, reports only a single temperature. If this is not a limitation of the HW, I would like to try my hand at adding features. It would be my first foray into the Linux kernel, so, even with solid HW information, it may go a bit slowly. Any pointers to how to get sensor data or other monitoring info on the 5825U would be helpful.

Thanks - Dan

[cyring · Accepted solution]

Mobile Ryzen processors tested here reported only a single thermal sensor.

Feel free to dig into CoreFreq source code but I believe, as k10temp, it's the same SMU registers set for Thermal DTS and offsets. 

[danielmgessel]

Oh hey, thanks! CoreFreq looks really nice!

But I'm a little disappointed to hear that there are so few temperature sensors available even to the OS...

[cyring]

They might be more but there's a lack of specifications if others exist. 

TSI protocol is worth to try. Still needs an implementation. 

TSI is just documented into the AMD family 17h & 19h PPR.

But by the end of the day, I wonder if all this coding effort will bring more thermal data than the SMU way ?

I even wonder if SMU thermal is just based on TSI interface which brings back us to square one. 

[danielmgessel]

I'll see if I can get any info about what sensors actually exist in the HW and how to get at them. I'm new to this (I worked on GPU drivers), so there's alot to learn (🤯) and any progress will be slow...  If I do get anywhere, I'll ping you here or on the CoreFreq repo on GitHub.