Public bug reported:

[Impact]
On some platforms, aggressive C1 auto-demotion may lead to failure to enter
the deepest C-state during suspend-to-idle, causing high power consumption.
To prevent this, disable C1 auto-demotion during suspend and re-enable on
resume.

[Fix]
Below 2 commits in linux-next fix the issue
7a797cc9f809 platform/x86/intel/pmc: Disable C1 auto-demotion during suspend
9fe43c8020a6 platform/x86/intel/pmc: Refactor platform resume functions to use 
cnl_resume()

[Test]
Connect the power meter on the machine(MTL/ARL/LNL) and run s2idle tests 
multiple times,
it should consume ~0.5w during s2idle.

[Where problems could occur]
It's hard to tell what could cause changes to the CPU flags.
So, only submit this to OEM kernel.

** Affects: hwe-next
     Importance: Undecided
         Status: New

** Affects: linux-oem-6.11 (Ubuntu)
     Importance: Undecided
         Status: Invalid

** Affects: linux-oem-6.11 (Ubuntu Noble)
     Importance: Undecided
     Assignee: AceLan Kao (acelankao)
         Status: In Progress


** Tags: jira-wtn-10 oem-priority

** Also affects: linux-oem-6.11 (Ubuntu Noble)
   Importance: Undecided
       Status: New

** Changed in: linux-oem-6.11 (Ubuntu Noble)
       Status: New => In Progress

** Changed in: linux-oem-6.11 (Ubuntu Noble)
     Assignee: (unassigned) => AceLan Kao (acelankao)

** Changed in: linux-oem-6.11 (Ubuntu)
       Status: New => Invalid

** Tags added: jira-wtn-10 oem-priority

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https://bugs.launchpad.net/bugs/2088964

Title:
  Disable C1 auto-demotion during suspend for MTL/ARL/LNL platforms

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