linux/drivers/pci
Lukas Wunner 8ef0217227 PCI/PM: Observe reset delay irrespective of bridge_d3
If a PCI bridge is suspended to D3cold upon entering system sleep,
resuming it entails a Fundamental Reset per PCIe r6.0 sec 5.8.

The delay prescribed after a Fundamental Reset in PCIe r6.0 sec 6.6.1
is sought to be observed by:

  pci_pm_resume_noirq()
    pci_pm_bridge_power_up_actions()
      pci_bridge_wait_for_secondary_bus()

However, pci_bridge_wait_for_secondary_bus() bails out if the bridge_d3
flag is not set.  That flag indicates whether a bridge is allowed to
suspend to D3cold at *runtime*.

Hence *no* delay is observed on resume from system sleep if runtime
D3cold is forbidden.  That doesn't make any sense, so drop the bridge_d3
check from pci_bridge_wait_for_secondary_bus().

The purpose of the bridge_d3 check was probably to avoid delays if a
bridge remained in D0 during suspend.  However the sole caller of
pci_bridge_wait_for_secondary_bus(), pci_pm_bridge_power_up_actions(),
is only invoked if the previous power state was D3cold.  Hence the
additional bridge_d3 check seems superfluous.

Fixes: ad9001f2f4 ("PCI/PM: Add missing link delays required by the PCIe spec")
Link: https://lore.kernel.org/r/eb37fa345285ec8bacabbf06b020b803f77bdd3d.1673769517.git.lukas@wunner.de
Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: stable@vger.kernel.org # v5.5+
2023-02-07 11:54:03 -06:00
..
controller phy-for-6.2 2022-12-19 08:40:58 -06:00
endpoint Merge branch 'remotes/lorenzo/pci/misc' 2022-12-10 10:36:40 -06:00
hotplug PCI: pciehp: Enable Command Completed Interrupt only if supported 2022-12-07 08:27:20 -06:00
msi PCI/MSI: Provide pci_ims_alloc/free_irq() 2022-12-05 22:22:35 +01:00
pcie pci-v6.2-changes 2022-12-14 09:54:10 -08:00
switch PCI: switchtec: Prefer ida_alloc()/free() over ida_simple_get()/remove() 2022-06-09 12:28:21 -05:00
access.c PCI: Access Link 2 registers only for devices with Links 2022-11-04 10:38:11 -05:00
ats.c PCI: Enable PASID only when ACS RR & UF enabled on upstream path 2022-11-03 15:47:47 +01:00
bus.c PCI: Skip allocate_resource() if too little space available 2022-12-10 10:31:47 -06:00
doe.c PCI/DOE: Fix maximum data object length miscalculation 2022-11-16 14:26:46 -06:00
ecam.c
host-bridge.c
iov.c PCI/IOV: Fix wrong kernel-doc identifier 2022-03-07 12:06:10 -07:00
irq.c PCI: Check for alloc failure in pci_request_irq() 2022-11-21 16:55:18 -06:00
Kconfig genirq: Get rid of GENERIC_MSI_IRQ_DOMAIN 2022-11-17 15:15:20 +01:00
Makefile PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
mmap.c PCI: Remove pci_mmap_page_range() wrapper 2022-07-29 12:08:44 -05:00
of.c IOMMU Updates for Linux v5.19 2022-05-31 09:56:54 -07:00
p2pdma.c for-6.2/block-2022-12-08 2022-12-13 10:43:59 -08:00
pci-acpi.c PCI/ACPI: Use METHOD_NAME__UID instead of plain string 2022-11-07 15:22:52 -06:00
pci-bridge-emul.c PCI: pci-bridge-emul: Set position of PCI capabilities to real HW value 2022-08-25 12:07:56 +02:00
pci-bridge-emul.h PCI: pci-bridge-emul: Set position of PCI capabilities to real HW value 2022-08-25 12:07:56 +02:00
pci-driver.c PCI/PM: Remove unused 'state' parameter to pci_legacy_suspend_late() 2022-10-26 11:26:11 -05:00
pci-label.c
pci-mid.c
pci-pf-stub.c
pci-stub.c PCI: pci_stub: Set driver_managed_dma 2022-04-28 15:32:20 +02:00
pci-sysfs.c pci-v6.2-changes 2022-12-14 09:54:10 -08:00
pci.c PCI/PM: Observe reset delay irrespective of bridge_d3 2023-02-07 11:54:03 -06:00
pci.h PCI: Access Link 2 registers only for devices with Links 2022-11-04 10:38:11 -05:00
probe.c pci-v6.2-changes 2022-12-14 09:54:10 -08:00
proc.c PCI: Remove pci_mmap_page_range() wrapper 2022-07-29 12:08:44 -05:00
quirks.c PCI/DPC: Quirk PIO log size for certain Intel Root Ports 2022-09-27 18:13:18 -05:00
remove.c PCI: Assign PCI domain IDs by ida_alloc() 2022-11-08 11:14:18 -06:00
rom.c
search.c
setup-bus.c Revert "PCI: Distribute available resources for root buses, too" 2022-10-14 14:27:58 -05:00
setup-irq.c
setup-res.c PCI: Sanitise firmware BAR assignments behind a PCI-PCI bridge 2022-09-21 17:52:47 -05:00
slot.c
syscall.c
vc.c
vgaarb.c PCI/VGA: Replace full MIT license text with SPDX identifier 2022-03-09 18:31:34 -06:00
vpd.c
xen-pcifront.c xen/pcifront: move xenstore config scanning into sub-function 2022-10-07 07:36:44 +02:00