Hi Ganapathi,

> OK; Thanks for this; I read it as 'these two issues have different root
> causes';

Not sure if that's the case since we enable link power saving after
every suspend again.

> it is enabled(above output of lspci -vvv); but is there a seperate check to
> know if it could be *entered*;

I don't think there is, maybe there are unofficial debugging tools by
Intel or related manufacturers to read statistics about those states
from the chipset.

> cat: /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us: No
> such file or directory

Sounds like the processor used in the Pro 4 isn't new enough, from the
cpu residency it sounds like S0Ix is working. You can read more about
those states here: https://01.org/blogs/qwang59/2018/how-achieve-s0ix-
states-linux


Also I figured out what the fix for the "Firmware wakeup failed" errors I wrote 
about was: Sleeping for about a second before writing to the PCI power state 
register, so not really a fix, just a workaround...

If you fail to reproduce the issue on the Pro 4 maybe you can get a Pro
2017 and try it on that?

Thanks,
Jonas

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1730924

Title:
  Wifi does down "crash" in Surface Pro 4

Status in Linux:
  Confirmed
Status in linux package in Ubuntu:
  Incomplete

Bug description:
  I have a Surface Pro 4. The wifi works well in principle, but unfortunately 
it drops every x minutes. The only way to fix it I've found is to reboot the 
computer.
  lsb_release -rd
  Description:    Ubuntu 17.10
  Release:        17.10

  ProblemType: Bug
  DistroRelease: Ubuntu 17.10
  Package: linux-image-4.13.0-16-generic 4.13.0-16.19
  ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4
  Uname: Linux 4.13.0-16-generic x86_64
  ApportVersion: 2.20.7-0ubuntu3.1
  Architecture: amd64
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  predatux   1537 F.... pulseaudio
  CurrentDesktop: KDE
  Date: Wed Nov  8 10:41:26 2017
  HibernationDevice: RESUME=UUID=147af4ba-a4ce-41fe-a176-b36a1f6a590b
  Lsusb:
   Bus 002 Device 002: ID 045e:090c Microsoft Corp. 
   Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
   Bus 001 Device 002: ID 045e:07e8 Microsoft Corp. 
   Bus 001 Device 003: ID 1286:204c Marvell Semiconductor, Inc. 
   Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
  MachineType: Microsoft Corporation Surface Pro 4
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.13.0-16-generic 
root=UUID=125200b0-7377-4985-a217-15503781a525 ro quiet splash vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-4.13.0-16-generic N/A
   linux-backports-modules-4.13.0-16-generic  N/A
   linux-firmware                             1.169
  SourcePackage: linux
  UpgradeStatus: Upgraded to artful on 2017-10-22 (16 days ago)
  dmi.bios.date: 02/24/2017
  dmi.bios.vendor: Microsoft Corporation
  dmi.bios.version: 106.1624.768
  dmi.board.name: Surface Pro 4
  dmi.board.vendor: Microsoft Corporation
  dmi.chassis.type: 9
  dmi.chassis.vendor: Microsoft Corporation
  dmi.modalias: 
dmi:bvnMicrosoftCorporation:bvr106.1624.768:bd02/24/2017:svnMicrosoftCorporation:pnSurfacePro4:pvrD0B08F1C03P38:rvnMicrosoftCorporation:rnSurfacePro4:rvr:cvnMicrosoftCorporation:ct9:cvr:
  dmi.product.family: Surface
  dmi.product.name: Surface Pro 4
  dmi.product.version: D:0B:08F:1C:03P:38
  dmi.sys.vendor: Microsoft Corporation

To manage notifications about this bug go to:
https://bugs.launchpad.net/linux/+bug/1730924/+subscriptions

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to