Public bug reported:

===SRU Justification===
[Impact]
Intel CPU can't reach beyond Package C-State 3 (PC3). Drains lots of power.

[Test]
Check the value of 
/sys/devices/pci0000:00/0000:00:17.0/ata1/host0/scsi_host/host0/link_power_management_policy.

It's med_power_with_dipm as default.
Also check the powertop, it can reach PC8.

[Fix]
Introduce a new config to let AHCI pick med_power_with_dipm for mobile 
platforms.

[Regression Potential]
Medium. Some SATA devices are broken under med_power_with_dipm or min_power.
Fortunately this is for -oem kernel only, so every SATA device gets tested 
before shipping to customers.

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

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https://bugs.launchpad.net/bugs/1778029

Title:
  Use "Medium power with Device Initiated PM" as default LPM policy for
  mobile SATA devices

Status in linux-oem package in Ubuntu:
  New

Bug description:
  ===SRU Justification===
  [Impact]
  Intel CPU can't reach beyond Package C-State 3 (PC3). Drains lots of power.

  [Test]
  Check the value of 
/sys/devices/pci0000:00/0000:00:17.0/ata1/host0/scsi_host/host0/link_power_management_policy.

  It's med_power_with_dipm as default.
  Also check the powertop, it can reach PC8.

  [Fix]
  Introduce a new config to let AHCI pick med_power_with_dipm for mobile 
platforms.

  [Regression Potential]
  Medium. Some SATA devices are broken under med_power_with_dipm or min_power.
  Fortunately this is for -oem kernel only, so every SATA device gets tested 
before shipping to customers.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-oem/+bug/1778029/+subscriptions

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