Bug 201523

Suspending a Dell XPS 13 9370 laptop fails to enter c0ix sleep states.

I followed this guide to check if c0ix states are supported: https://01.org/blogs/qwang59/2018/how-achieve-s0ix-states-linux. Confirmed that this system supports c0ix states.

To reproduce:
$ sudo powertop --auto-tune
$ sudo turbostat --show SYS%LPI rtcwake -m freeze -s 15
rtcwake: wakeup from "freeze" using /dev/rtc0 at Fri Oct 26 16:30:17 2018
16.767175 sec
SYS%LPI
0.00
0.00
$ cat /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us
0

I expect system to enter LPI states, but it doesn't.

Idle driver:
$ cat /sys/devices/system/cpu/cpuidle/current_driver
intel_idle

Turbostat:
$ sudo turbostat --show sysfs --quiet sleep 10
10.007904 sec
POLL	C1	C1E	C3	C6	C7s	C8	C9	C10	POLL%	C1%	C1E%	C3%	C6%	C7s%	C8%	C9%	C10%
2	80	380	460	2270	12	2515	152	4267	0.00	0.03	0.07	0.07	1.75	0.01	2.97	0.82	91.95
0	9	72	90	274	0	444	45	743	0.00	0.00	0.06	0.09	1.50	0.00	4.24	1.33	90.39
1	8	49	65	206	0	191	8	556	0.00	0.02	0.06	0.07	1.30	0.00	1.82	0.23	93.90
0	32	87	67	552	1	275	26	448	0.00	0.15	0.22	0.12	3.62	0.01	2.44	0.74	89.78
0	1	4	10	94	0	64	0	348	0.00	0.00	0.00	0.01	0.63	0.00	0.57	0.00	97.39
0	4	20	24	267	5	478	11	425	0.00	0.00	0.05	0.06	1.95	0.04	4.29	0.24	91.42
0	1	12	24	143	0	107	5	269	0.00	0.00	0.01	0.03	0.82	0.00	0.92	0.17	96.40
0	22	80	112	528	4	718	51	936	0.00	0.03	0.10	0.10	2.92	0.02	7.32	3.76	82.35
1	3	56	68	206	2	238	6	542	0.00	0.00	0.08	0.07	1.28	0.02	2.15	0.07	93.97


I enabled pm debug messages:
# echo 1 > /sys/power/pm_debug_messages

[  211.128966] PM: suspend entry (s2idle)
[  211.128968] PM: Syncing filesystems ... done.
[  211.129324] PM: Preparing system for sleep (s2idle)
[  211.130639] Freezing user space processes ... (elapsed 0.003 seconds) done.
[  211.133986] OOM killer disabled.
[  211.133987] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[  211.135499] PM: Suspending system (s2idle)
[  211.135501] Suspending console(s) (use no_console_suspend to debug)
[  211.350902] psmouse serio1: Failed to disable mouse on isa0060/serio1
[  213.144012] PM: suspend of devices complete after 2008.173 msecs
[  213.144016] PM: suspend devices took 2.009 seconds
[  213.159851] PM: late suspend of devices complete after 15.822 msecs
[  213.176969] PM: suspend-to-idle
[  213.214718] PM: noirq suspend of devices aborted after 37.662 msecs
[  213.214721] ACPI: \_PR_.PR00: LPI: Device not power manageable
[  213.214722] ACPI: \_PR_.PR01: LPI: Device not power manageable
[  213.214723] ACPI: \_PR_.PR02: LPI: Device not power manageable
[  213.214724] ACPI: \_PR_.PR03: LPI: Device not power manageable
[  213.214725] ACPI: \_PR_.PR04: LPI: Device not power manageable
[  213.214726] ACPI: \_PR_.PR05: LPI: Device not power manageable
[  213.214727] ACPI: \_PR_.PR06: LPI: Device not power manageable
[  213.214728] ACPI: \_PR_.PR07: LPI: Device not power manageable
[  213.214729] ACPI: \_SB_.PCI0.GFX0: LPI: Device not power manageable
[  213.214732] ACPI: \_SB_.PCI0.RP03.PXSX: LPI: Device not power manageable
[  213.214733] ACPI: \_SB_.PCI0.RP09.PXSX: LPI: Device not power manageable
[  213.244585] PM: noirq resume of devices complete after 29.837 msecs
[  213.290838] PM: noirq suspend of devices complete after 46.088 msecs
[  226.521418] PM: Timekeeping suspended for 14.000 seconds
[  226.554553] PM: noirq resume of devices complete after 32.920 msecs
[  226.554842] PM: resume from suspend-to-idle
[  226.568725] PM: early resume of devices complete after 3.425 msecs
[  226.604769] ACPI: button: The lid device is not compliant to SW_LID.
[  226.715600] r8152 4-2.2:1.0 enp57s0u2u2: carrier on
[  227.261899] ath10k_pci 0000:02:00.0: Unknown eventid: 118809
[  227.264979] ath10k_pci 0000:02:00.0: Unknown eventid: 90118
[  227.361172] PM: resume of devices complete after 792.449 msecs
[  227.361613] PM: resume devices took 0.793 seconds
[  227.361615] PM: Finishing wakeup.
[  227.361615] OOM killer enabled.
[  227.361616] Restarting tasks ... done.
[  227.408015] PM: suspend exit