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# SPDX-License-Identifier: GPL-2.0
#
# CONFIG_PCI Express Port Bus Configuration
#
config CONFIG_PCIEPORTBUS
	bool "PCI Express Port Bus support"
	depends on CONFIG_PCI
	help
	  This enables CONFIG_PCI Express Port Bus support. Users can then enable
	  support for Native Hot-Plug, Advanced Error Reporting, Power
	  Management Events, and Downstream Port Containment.

#
# Include service Kconfig here
#
config CONFIG_HOTPLUG_PCI_PCIE
	bool "PCI Express Hotplug driver"
	depends on CONFIG_HOTPLUG_PCI && CONFIG_PCIEPORTBUS
	help
	  Say Y here if you have a motherboard that supports CONFIG_PCI Express Native
	  Hotplug

	  When in doubt, say N.

config CONFIG_PCIEAER
	bool "PCI Express Advanced Error Reporting support"
	depends on CONFIG_PCIEPORTBUS
	select CONFIG_RAS
	default y
	help
	  This enables CONFIG_PCI Express Root Port Advanced Error Reporting
	  (AER) driver support. Error reporting messages sent to Root
	  Port will be handled by CONFIG_PCI Express AER driver.

config CONFIG_PCIEAER_INJECT
	tristate "PCI Express error injection support"
	depends on CONFIG_PCIEAER
	help
	  This enables CONFIG_PCI Express Root Port Advanced Error Reporting
	  (AER) software error injector.

	  Debugging AER code is quite difficult because it is hard
	  to trigger various real hardware errors. Software-based
	  error injection can fake almost all kinds of errors with the
	  help of a user space helper tool aer-inject, which can be
	  gotten from:
	     http://www.kernel.org/pub/linux/utils/pci/aer-inject/

#
# CONFIG_PCI Express ECRC
#
config CONFIG_PCIE_ECRC
	bool "PCI Express ECRC settings control"
	depends on CONFIG_PCIEAER
	help
	  Used to override firmware/bios settings for CONFIG_PCI Express ECRC
	  (transaction layer end-to-end CRC checking).

	  When in doubt, say N.

#
# CONFIG_PCI Express ASPM
#
config CONFIG_PCIEASPM
	bool "PCI Express ASPM control" if CONFIG_EXPERT
	depends on CONFIG_PCI && CONFIG_PCIEPORTBUS
	default y
	help
	  This enables OS control over CONFIG_PCI Express ASPM (Active State
	  Power Management) and Clock Power Management. ASPM supports
	  state L0/L0s/L1.

	  ASPM is initially set up by the firmware. With this option enabled,
	  Linux can modify this state in order to disable ASPM on known-bad
	  hardware or configurations and enable it when known-safe.

	  ASPM can be disabled or enabled at runtime via
	  /sys/module/pcie_aspm/parameters/policy

	  When in doubt, say Y.

config CONFIG_PCIEASPM_DEBUG
	bool "Debug PCI Express ASPM"
	depends on CONFIG_PCIEASPM
	help
	  This enables CONFIG_PCI Express ASPM debug support. It will add per-device
	  interface to control ASPM.

choice
	prompt "Default ASPM policy"
	default CONFIG_PCIEASPM_DEFAULT
	depends on CONFIG_PCIEASPM

config CONFIG_PCIEASPM_DEFAULT
	bool "BIOS default"
	depends on CONFIG_PCIEASPM
	help
	  Use the BIOS defaults for CONFIG_PCI Express ASPM.

config CONFIG_PCIEASPM_POWERSAVE
	bool "Powersave"
	depends on CONFIG_PCIEASPM
	help
	  Enable CONFIG_PCI Express ASPM L0s and L1 where possible, even if the
	  BIOS did not.

config CONFIG_PCIEASPM_POWER_SUPERSAVE
	bool "Power Supersave"
	depends on CONFIG_PCIEASPM
	help
	  Same as CONFIG_PCIEASPM_POWERSAVE, except it also enables L1 substates where
	  possible. This would result in higher power savings while staying in L1
	  where the components support it.

config CONFIG_PCIEASPM_PERFORMANCE
	bool "Performance"
	depends on CONFIG_PCIEASPM
	help
	  Disable CONFIG_PCI Express ASPM L0s and L1, even if the BIOS enabled them.
endchoice

config CONFIG_PCIE_PME
	def_bool y
	depends on CONFIG_PCIEPORTBUS && CONFIG_PM

config CONFIG_PCIE_DPC
	bool "PCI Express Downstream Port Containment support"
	depends on CONFIG_PCIEPORTBUS && CONFIG_PCIEAER
	help
	  This enables CONFIG_PCI Express Downstream Port Containment (DPC)
	  driver support.  DPC events from Root and Downstream ports
	  will be handled by the DPC driver.  If your system doesn't
	  have this capability or you do not want to use this feature,
	  it is safe to answer N.

config CONFIG_PCIE_PTM
	bool "PCI Express Precision Time Measurement support"
	depends on CONFIG_PCIEPORTBUS
	help
	  This enables CONFIG_PCI Express Precision Time Measurement (PTM)
	  support.

	  This is only useful if you have devices that support PTM, but it
	  is safe to enable even if you don't.

config CONFIG_PCIE_BW
	bool "PCI Express Bandwidth Change Notification"
	depends on CONFIG_PCIEPORTBUS
	help
	  This enables CONFIG_PCI Express Bandwidth Change Notification.  If
	  you know link width or rate changes occur only to correct
	  unreliable links, you may answer Y.