linux/drivers
Mika Westerberg bbe54ea533 PCI: pciehp: Disable Data Link Layer State Changed event on suspend
Commit 0e157e5286 ("PCI/PME: Implement runtime PM callbacks") tried to
solve an issue where the hierarchy immediately wakes up when it is
transitioned into D3cold.  However, it turns out to prevent PME
propagation on some systems that do not support D3cold.

I looked more closely at what might cause the immediate wakeup.  It happens
when the ACPI power resource of the root port is turned off.  The AML code
associated with the _OFF() method of the ACPI power resource starts a PCIe
L2/L3 Ready transition and waits for it to complete.  Right after the L2/L3
Ready transition is started the root port receives a PME from the
downstream port.

The simplest hierarchy where this happens looks like this:

  00:1d.0 PCIe Root Port
    ^
    |
    v
    05:00.0 PCIe switch #1 upstream port
      06:01.0 PCIe switch #1 downstream hotplug port
        ^
        |
        v
        08:00.0 PCIe switch #2 upstream port

It seems that the PCIe link between the two switches, before
PME_Turn_Off/PME_TO_Ack is complete for the whole hierarchy, goes
inactive and triggers PME towards the root port bringing it back to D0.
The L2/L3 Ready sequence is described in PCIe r4.0 spec sections 5.2 and
5.3.3 but unfortunately they do not state what happens if DLLSCE is
enabled during the sequence.

Disabling Data Link Layer State Changed event (DLLSCE) seems to prevent
the issue and still allows the downstream hotplug port to notice when a
device is plugged/unplugged.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=202593
Fixes: 0e157e5286 ("PCI/PME: Implement runtime PM callbacks")
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org	# v4.20+
2019-02-15 14:18:00 -06:00
..
accessibility
acpi Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
amba
android binder: implement binderfs 2018-12-19 09:40:13 +01:00
ata for-4.21/libata-20190102 2019-01-02 18:47:56 -08:00
atm
auxdisplay auxdisplay: charlcd: fix x/y command parsing 2018-12-21 21:27:21 +01:00
base Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:25:58 -08:00
bcma
block block: sunvdc: don't run hw queue synchronously from irq context 2019-01-03 08:21:47 -07:00
bluetooth Bluetooth: hci_bcm: Handle specific unknown packets after firmware loading 2018-12-19 13:43:42 +01:00
bus ARM: SoC driver updates 2018-12-31 17:32:35 -08:00
cdrom gdrom: fix a memory leak bug 2018-12-29 08:20:44 -07:00
char Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
clk Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2019-01-02 18:56:59 -08:00
clocksource arch/csky patches for 4.21-rc1 2019-01-05 09:50:07 -08:00
connector
cpufreq powerpc updates for 4.21 2018-12-27 10:43:24 -08:00
cpuidle powerpc updates for 4.21 2018-12-27 10:43:24 -08:00
crypto Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
dax mm, devm_memremap_pages: fix shutdown handling 2018-12-28 12:11:47 -08:00
dca
devfreq
dio
dma Merge branch 'next/drivers' into next/late 2019-01-04 14:31:38 -08:00
dma-buf drivers/dma-buf/udmabuf.c: convert to use vm_fault_t 2019-01-04 13:13:46 -08:00
edac EDAC, fsl_ddr: Add LS1021A to the list of supported hardware 2018-12-19 11:57:45 +01:00
eisa
extcon
firewire FireWire (IEEE 1394) subsystem patch: 2019-01-05 18:33:21 -08:00
firmware arm64 fixes for -rc1 2019-01-05 11:28:39 -08:00
fmc
fpga Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
fsi
gnss
gpio This is the bulk of GPIO changes for the v4.21 kernel series: 2018-12-28 20:00:21 -08:00
gpu drm i915 gvt, amdgpu, core fixes 2019-01-05 18:25:19 -08:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2019-01-05 17:53:40 -08:00
hsi
hv Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
hwmon Kconfig updates for v4.21 2018-12-29 13:03:29 -08:00
hwspinlock hwspinlock: fix return value check in stm32_hwspinlock_probe() 2019-01-03 11:42:10 -08:00
hwtracing intel_th: msu: Fix an off-by-one in attribute store 2018-12-19 20:21:06 +01:00
i2c Merge branch 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2019-01-05 18:13:35 -08:00
i3c
ide for-4.21/block-20181221 2018-12-28 13:19:59 -08:00
idle
iio Staging/IIO driver patches for 4.21-rc1 2018-12-28 20:39:58 -08:00
infiniband 4.21 merge window 2nd pull request 2019-01-05 18:20:51 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2019-01-02 18:56:59 -08:00
iommu IOMMU Updates for Linux v4.21 2019-01-01 15:55:29 -08:00
ipack
irqchip Xtensa updates for v4.21: 2018-12-29 09:40:40 -08:00
isdn isdn: fix kernel-infoleak in capi_unlocked_ioctl 2019-01-02 10:31:39 -08:00
leds LEDs for 4.21-rc1 2018-12-25 14:52:50 -08:00
lightnvm lightnvm: pblk: fix use-after-free bug 2018-12-22 14:45:35 -07:00
macintosh Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
mailbox mailbox: tegra-hsp: Use device-managed registration API 2018-12-21 22:31:26 -06:00
mcb
md Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md into for-linus 2019-01-03 08:21:02 -07:00
media Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
memory ARM: SoC: late updates 2019-01-05 11:30:37 -08:00
memstick MMC core: 2018-12-28 16:52:18 -08:00
message scsi: flip the default on use_clustering 2018-12-18 23:13:12 -05:00
mfd
misc Merge branch 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2019-01-05 18:13:35 -08:00
mmc MMC core: 2018-12-28 16:52:18 -08:00
mtd Kbuild updates for v4.21 2018-12-29 12:03:17 -08:00
mux
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-03 12:53:47 -08:00
nfc
ntb
nubus
nvdimm Merge branch 'akpm' (patches from Andrew) 2018-12-28 16:55:46 -08:00
nvme nvme-pci: trace SQ status on completions 2018-12-19 08:35:36 +01:00
nvmem
of Merge tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux 2018-12-28 20:08:34 -08:00
opp
oprofile
parisc Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
parport
pci PCI: pciehp: Disable Data Link Layer State Changed event on suspend 2019-02-15 14:18:00 -06:00
pcmcia Included in this update: 2019-01-05 11:23:17 -08:00
perf drivers/perf: hisi: Fixup one DDRC PMU register offset 2019-01-04 10:13:27 +00:00
phy
pinctrl Pin control bulk changes for the v4.21 kernel cycle: 2019-01-01 13:19:16 -08:00
platform chrome platform changes for v4.21 2019-01-06 11:40:06 -08:00
pnp Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
power power supply and reset changes for the v4.21 series 2018-12-28 20:22:45 -08:00
powercap
pps Kconfig updates for v4.21 2018-12-29 13:03:29 -08:00
ps3
ptp Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
pwm pwm: imx: Add ipg clock operation 2018-12-24 12:06:56 +01:00
rapidio
ras treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
regulator Merge remote-tracking branch 'regulator/topic/coupled' into regulator-next 2018-12-21 13:43:35 +00:00
remoteproc
reset
rpmsg
rtc RTC for 4.21 2019-01-01 13:24:31 -08:00
s390 s390 updates for the 4.21 merge window 2019-01-02 18:37:01 -08:00
sbus Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next 2018-12-26 10:32:18 -08:00
scsi Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
sfi
sh
siox
slimbus
sn
soc ARM: SoC driver updates 2018-12-31 17:32:35 -08:00
soundwire
spi spi: Updates for v4.21 2018-12-25 14:43:54 -08:00
spmi
ssb
staging Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
target SCSI misc on 20181224 2018-12-28 14:48:06 -08:00
tc
tee OP-TEE dynamic shm log message 2018-12-31 13:06:30 -08:00
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2019-01-05 16:07:28 -08:00
thunderbolt
tty ARM: SoC: late updates 2019-01-05 11:30:37 -08:00
uio Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
usb pci-v4.21-changes 2019-01-05 17:57:34 -08:00
uwb
vfio IOMMU Updates for Linux v4.21 2019-01-01 15:55:29 -08:00
vhost Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
video fbdev changes for v4.21: 2019-01-05 18:15:37 -08:00
virt
virtio virtio, vhost: features, fixes, cleanups 2019-01-02 18:54:45 -08:00
visorbus
vlynq
vme
w1 treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
watchdog linux-watchdog 4.21-rc1 tag 2019-01-01 13:16:45 -08:00
xen Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
zorro
Kconfig Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
Makefile