Is there CPPC Support on Threadripper 3000 platform?

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I’ve been wondering; Has people with Threadripper 3000 been able to enable CPPC and use AMD P-State driver?
Currently, the Gigabyte TRX40 AORUS XTREME on AGESA 1.0.0.7 (P6) does show CPPC in the bios, but it doesn’t do anything. Probably faulty / un supported configuration not sure.
I want to use AMD P-state driver out of mild curiosity what kind of performance impact it has over the default one.

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@FutureFade I’ve been wondering the exact same thing. I’ve done everything necessary to enable CPPC and the AMD P-State driver on a system with an ASUS TRX40 Zenith II Extreme, and when I check journalctl for amd-pstate, there’s an entry that says the kernel doesn’t see a _CPC object.

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I cannot figure out what CPPC is truly for. What is a use case where it makes a significant difference? Why was it developed in the first place? What I can find online looks like CPU optimization masturbation, so I assume there must be more to it.

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Just put the latest BIOS on my Zenith II Extreme, and I’m running kernel 6.4.1, and the AMD P-State driver is still not working. Same error as before: “amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled”

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I’ve been working on the same thing with the 6.4 kernel where it is suppose to be enabled by default but alas i’m getting the same as you - some SBIOS _CPC flag not on the cpu feature extensions. I"m running the TRX40-Prime Pro with a 3960X.

I have gotten this to work on my laptop 5900HS full ACPI suppose since there were patches - So 5.something kernel.

My guess is with others - its not been enabled in the bios. I have still been updating mine as recent as the last couple months.

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Hi,

Can someone with AMD P-STATE working on their system please do the following:

  1. copy the files under /sys/firmware/acpi/tables/ to a local directory
  2. chmod or chown them to give yourself access
  3. run iasl -d * on the files
  4. grep the files for ‘_CPC’, hopfully this will help identify which ACPI table has the CPC data.
  5. post one of the ‘Scope’ sections that has the structure inside that contains the _CPC data

thanks

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Some good news dropped at phoronix

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Good news! Just installed kernel 6.8.9 on OpenSUSE Leap 15.5, and added amd_pstate=active to the kernel command line. Scaling driver is now amd-pstate-epp. It was the line change in the kernel that was done recently. That was the whole problem.

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