Re: [PATCH v2 0/5] hwmon: k10temp driver improvements

[Ken Moffat]

On Sat, 18 Jan 2020 at 17:26, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> This patch series implements various improvements for the k10temp driver.
>
> Patch 1/5 introduces the use of bit operations.
>
> Patch 2/5 converts the driver to use the devm_hwmon_device_register_with_info
> API. This not only simplifies the code and reduces its size, it also
> makes the code easier to maintain and enhance.
>
> Patch 3/5 adds support for reporting Core Complex Die (CCD) temperatures
> on Ryzen 3 (Zen2) CPUs.
>
> Patch 4/5 adds support for reporting core and SoC current and voltage
> information on Ryzen CPUs.
>
> Patch 5/5 removes the maximum temperature from Tdie for Ryzen CPUs.
> It is inaccurate, misleading, and it just doesn't make sense to report
> wrong information.
>
> With all patches in place, output on Ryzen 3900X CPUs looks as follows
> (with the system under load).
>
> k10temp-pci-00c3
> Adapter: PCI adapter
> Vcore:        +1.36 V
> Vsoc:         +1.18 V
> Tdie:         +86.8ÂC
> Tctl:         +86.8ÂC
> Tccd1:        +80.0ÂC
> Tccd2:        +81.8ÂC
> Icore:       +44.14 A
> Isoc:        +13.83 A
>
> The voltage and current information is limited to Ryzen CPUs. Voltage
> and current reporting on Threadripper and EPYC CPUs is different, and the
> reported information is either incomplete or wrong. Exclude it for the time
> being; it can always be added if/when more information becomes available.
>
> Tested with the following Ryzen CPUs:
>     1300X A user with this CPU in the system reported somewhat unexpected
>           values for Vcore; it isn't entirely if at all clear why that is
>           the case. Overall this does not warrant holding up the series.

As the owner of that machine, very much agreed.

>     1600
>     1800X
>     2200G
>     2400G
>     3800X
>     3900X
>     3950X
>

I also had sensible results for v1 on 2500U and 3400G

> v2: Added tested-by: tags as received.
>     Don't display voltage and current information for Threadripper and EPYC.
>     Stop displaying the fixed (and wrong) maximum temperature of 70 degrees C
>     for Tdie on model 17h/18h CPUs.

For v2 on my 2500U, system idle and then under load -

--- k10temp-idle 2020-01-19 00:16:18.812002121 +0000
+++ k10temp-load 2020-01-19 00:22:05.595470877 +0000
@@ -1,15 +1,15 @@
 k10temp-pci-00c3
 Adapter: PCI adapter
-Vcore:        +0.98 V
+Vcore:        +1.15 V
 Vsoc:         +0.93 V
-Tdie:         +38.2ÂC
-Tctl:         +38.2ÂC
-Icore:       +10.39 A
-Isoc:         +6.49 A
+Tdie:         +76.2ÂC
+Tctl:         +76.2ÂC
+Icore:       +51.96 A
+Isoc:         +7.58 A

 amdgpu-pci-0300
 Adapter: PCI adapter
 vddgfx:           N/A
 vddnb:            N/A
-edge:         +38.0ÂC  (crit = +80.0ÂC, hyst =  +0.0ÂC)
+edge:         +76.0ÂC  (crit = +80.0ÂC, hyst =  +0.0ÂC)

I'll ony test v2 on the 3400G if you think the results would add something.

Äen
-- 
If a man stands before a mirror and sees in it his reflection, what
he sees is not a true reproduction, but a picture of himself when he
was a younger man.        -- de Selby