topic Re: list of c-states, p-states and operation of HWPM. in Mobile and Desktop Processors

list of c-states, p-states and operation of HWPM.

Steve_Kruglov — Thu, 16 Sep 2021 07:46:15 GMT

Dear Sirs, I have two questions about Intel CPU architecture:

1) Does the number of p-states and c-states is predefined for each processor core and where I can search for the list of the states for a particular processor? For example for Xeon E5-2690 V2

2) Where can I read in more details about Hardware Power Management (HWPM)? I am interested in how processor control unit (PCU) perform autonomous control and how it interacts with operating system via native mode?

Thank you in advance.

Re:list of c-states, p-states and operation of HWPM.

Leonardo_C_Intel — Thu, 16 Sep 2021 19:22:49 GMT

Hello StepanKruglo,

Thank you for posting in the Intel Community.

We would like to share with you that due to the Intel® Xeon® Processor E5-2690 v2https://ark.intel.com/content/www/us/en/ark/products/75279/intel-xeon-processor-e5-2690-v2-25m-cache-3-00-ghz.htmldiscontinued status, Intel Customer Service no longer supports inquiries for it, but perhaps fellow community members have the knowledge to jump in and help.

Regards,

Leonardo C.

Intel Customer Support Technician

Re: list of c-states, p-states and operation of HWPM.

n_scott_pearson — Thu, 16 Sep 2021 20:45:23 GMT

The answer to the first question, and perhaps the second, can be found in the datasheets, which you can download from here: https://www.intel.com/content/www/us/en/processors/xeon/xeon-technical-resources.html.

Here is the information included therein regarding the states supported:

1. Processor Package and Core States

ACPI C-states as implemented by the following processor C-states:
- Package: PC0, PC1/PC1e, PC2, PC3, PC6 (Package C7 is not supported)
- Core: CC0, CC1, CC1E, CC3, CC6 (Processor Core C7 is not supported)
Enhanced Intel SpeedStep® Technology

2. System States Supported:

S0, S1, S3, S4, S5

Hope this helps,

...S

Re: Re:list of c-states, p-states and operation of HWPM.

Steve_Kruglov — Fri, 17 Sep 2021 06:41:00 GMT

Dear Leonardo,

this link doesn't contain the information I need. If you don't support this processor give me the same information for any of currently supported. for example for Intel® Xeon® E-2386G Processor (12M Cache, 3.50 GHz).

Stepan

Re: list of c-states, p-states and operation of HWPM.

Steve_Kruglov — Fri, 17 Sep 2021 07:25:05 GMT

Dear Scott,

thank you, you are very helpful. that is part of what I searched for.

May I ask you to give a link to the specific document where you took the information from?

I must be blind because the only information I found was in this document, and it is less comprehensive.

Re: list of c-states, p-states and operation of HWPM.

n_scott_pearson — Sun, 19 Sep 2021 05:56:55 GMT

Stepan,

As I said, the information was gleaned from the processor family datasheet that covers this processor. As I also said, documents, including datasheets, for Xeon processors can be downloaded from this page: https://www.intel.com/content/www/us/en/processors/xeon/xeon-technical-resources.html. I agree that the only description for the interface offered by this page is HORRIBLE!

To help you out, here are the links for this processor family that includes the Xeon E5-2690 V2:

The information I detailed can be found in Datasheet Volume 1, Section 1.3, Power Management Support.

...S

Re: list of c-states, p-states and operation of HWPM.

Steve_Kruglov — Mon, 20 Sep 2021 07:52:40 GMT

Dear Scott,

unfortunately the links to Datasheet volume1 and volume2 redirects me to https://www.intel.com/content/www/us/en/products/details/processors/xeon/scalable.html. Is it a problem with a link or on my side? Do those links work for you?

Re: list of c-states, p-states and operation of HWPM.

n_scott_pearson — Mon, 20 Sep 2021 08:27:50 GMT

As I said, page is HORRIBLE; links broken all over the place. Intel Customer Support (@Ronny_G_Intel?) is going to have to step in here and sort out how this page gets fixed and these documents can be downloaded.

In the meantime, I have attached the old versions that I had in my archive.

...S

Re: list of c-states, p-states and operation of HWPM.

Ronny_G_Intel — Tue, 21 Sep 2021 21:12:12 GMT

Hi @n_scott_pearson, @Steve_Kruglov

I totally see what you are saying, let me report this up to the Processors team, and thanks for the feedback!

Regards,

Ronny G

Re: list of c-states, p-states and operation of HWPM.

Steve_Kruglov — Thu, 30 Sep 2021 14:23:10 GMT

Thank you.