linux/drivers/pci/Kconfig

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# SPDX-License-Identifier: GPL-2.0
#
# PCI configuration
#
# select this to offer the PCI prompt
config HAVE_PCI
bool
# select this to unconditionally force on PCI support
config FORCE_PCI
bool
select HAVE_PCI
select PCI
menuconfig PCI
bool "PCI support"
depends on HAVE_PCI
help
This option enables support for the PCI local bus, including
support for PCI-X and the foundations for PCI Express support.
Say 'Y' here unless you know what you are doing.
if PCI
config PCI_DOMAINS
bool
depends on PCI
config PCI_DOMAINS_GENERIC
bool
select PCI_DOMAINS
config PCI_SYSCALL
bool
source "drivers/pci/pcie/Kconfig"
config PCI_MSI
bool "Message Signaled Interrupts (MSI and MSI-X)"
select GENERIC_MSI_IRQ
help
This allows device drivers to enable MSI (Message Signaled
Interrupts). Message Signaled Interrupts enable a device to
generate an interrupt using an inbound Memory Write on its
PCI bus instead of asserting a device IRQ pin.
Use of PCI MSI interrupts can be disabled at kernel boot time
by using the 'pci=nomsi' option. This disables MSI for the
entire system.
If you don't know what to do here, say Y.
config PCI_MSI_IRQ_DOMAIN
def_bool ARC || ARM || ARM64 || X86
depends on PCI_MSI
select GENERIC_MSI_IRQ_DOMAIN
config PCI_QUIRKS
default y
bool "Enable PCI quirk workarounds" if EXPERT
help
This enables workarounds for various PCI chipset bugs/quirks.
Disable this only if your target machine is unaffected by PCI
quirks.
config PCI_DEBUG
bool "PCI Debugging"
depends on DEBUG_KERNEL
help
Say Y here if you want the PCI core to produce a bunch of debug
messages to the system log. Select this if you are having a
problem with PCI support and want to see more of what is going on.
When in doubt, say N.
config PCI_REALLOC_ENABLE_AUTO
bool "Enable PCI resource re-allocation detection"
depends on PCI_IOV
help
Say Y here if you want the PCI core to detect if PCI resource
re-allocation needs to be enabled. You can always use pci=realloc=on
or pci=realloc=off to override it. It will automatically
re-allocate PCI resources if SR-IOV BARs have not been allocated by
the BIOS.
When in doubt, say N.
config PCI_STUB
tristate "PCI Stub driver"
help
Say Y or M here if you want be able to reserve a PCI device
when it is going to be assigned to a guest operating system.
When in doubt, say N.
config PCI_PF_STUB
tristate "PCI PF Stub driver"
depends on PCI_IOV
help
Say Y or M here if you want to enable support for devices that
require SR-IOV support, while at the same time the PF (Physical
Function) itself is not providing any actual services on the
host itself such as storage or networking.
When in doubt, say N.
config XEN_PCIDEV_FRONTEND
tristate "Xen PCI Frontend"
depends on X86 && XEN
select PCI_XEN
select XEN_XENBUS_FRONTEND
default y
help
The PCI device frontend driver allows the kernel to import arbitrary
PCI devices from a PCI backend to support PCI driver domains.
config PCI_ATS
bool
config PCI_ECAM
bool
config PCI_LOCKLESS_CONFIG
bool
PCI: Introduce PCI bridge emulated config space common logic Some PCI host controllers do not expose a configuration space for the root port PCI bridge. Due to this, the Marvell Armada 370/38x/XP PCI controller driver (pci-mvebu) emulates a root port PCI bridge configuration space, and uses that to (among other things) dynamically create the memory windows that correspond to the PCI MEM and I/O regions. Since we now need to add a very similar logic for the Marvell Armada 37xx PCI controller driver (pci-aardvark), instead of duplicating the code, we create in this commit a common logic called pci-bridge-emul. The idea of this logic is to emulate a root port PCI bridge configuration space by providing configuration space read/write operations, and faking behind the scenes the configuration space of a PCI bridge. A PCI host controller driver simply has to call pci_bridge_emul_conf_read() and pci_bridge_emul_conf_write() to read/write the configuration space of the bridge. By default, the PCI bridge configuration space is simply emulated by a chunk of memory, but the PCI host controller can override the behavior of the read and write operations on a per-register basis to do additional actions if needed. We take care of complying with the behavior of the PCI configuration space registers in terms of bits that are read-write, read-only, reserved and write-1-to-clear. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-18 15:37:16 +00:00
config PCI_BRIDGE_EMUL
bool
config PCI_IOV
bool "PCI IOV support"
select PCI_ATS
help
I/O Virtualization is a PCI feature supported by some devices
which allows them to create virtual devices which share their
physical resources.
If unsure, say N.
config PCI_PRI
bool "PCI PRI support"
select PCI_ATS
help
PRI is the PCI Page Request Interface. It allows PCI devices that are
behind an IOMMU to recover from page faults.
If unsure, say N.
config PCI_PASID
bool "PCI PASID support"
select PCI_ATS
help
Process Address Space Identifiers (PASIDs) can be used by PCI devices
to access more than one IO address space at the same time. To make
use of this feature an IOMMU is required which also supports PASIDs.
Select this option if you have such an IOMMU and want to compile the
driver for it into your kernel.
If unsure, say N.
PCI/P2PDMA: Support peer-to-peer memory Some PCI devices may have memory mapped in a BAR space that's intended for use in peer-to-peer transactions. To enable such transactions the memory must be registered with ZONE_DEVICE pages so it can be used by DMA interfaces in existing drivers. Add an interface for other subsystems to find and allocate chunks of P2P memory as necessary to facilitate transfers between two PCI peers: struct pci_dev *pci_p2pmem_find[_many](); int pci_p2pdma_distance[_many](); void *pci_alloc_p2pmem(); The new interface requires a driver to collect a list of client devices involved in the transaction then call pci_p2pmem_find() to obtain any suitable P2P memory. Alternatively, if the caller knows a device which provides P2P memory, they can use pci_p2pdma_distance() to determine if it is usable. With a suitable p2pmem device, memory can then be allocated with pci_alloc_p2pmem() for use in DMA transactions. Depending on hardware, using peer-to-peer memory may reduce the bandwidth of the transfer but can significantly reduce pressure on system memory. This may be desirable in many cases: for example a system could be designed with a small CPU connected to a PCIe switch by a small number of lanes which would maximize the number of lanes available to connect to NVMe devices. The code is designed to only utilize the p2pmem device if all the devices involved in a transfer are behind the same PCI bridge. This is because we have no way of knowing whether peer-to-peer routing between PCIe Root Ports is supported (PCIe r4.0, sec 1.3.1). Additionally, the benefits of P2P transfers that go through the RC is limited to only reducing DRAM usage and, in some cases, coding convenience. The PCI-SIG may be exploring adding a new capability bit to advertise whether this is possible for future hardware. This commit includes significant rework and feedback from Christoph Hellwig. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> [bhelgaas: fold in fix from Keith Busch <keith.busch@intel.com>: https://lore.kernel.org/linux-pci/20181012155920.15418-1-keith.busch@intel.com, to address comment from Dan Carpenter <dan.carpenter@oracle.com>, fold in https://lore.kernel.org/linux-pci/20181017160510.17926-1-logang@deltatee.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-10-04 21:27:35 +00:00
config PCI_P2PDMA
bool "PCI peer-to-peer transfer support"
depends on ZONE_DEVICE
PCI/P2PDMA: Support peer-to-peer memory Some PCI devices may have memory mapped in a BAR space that's intended for use in peer-to-peer transactions. To enable such transactions the memory must be registered with ZONE_DEVICE pages so it can be used by DMA interfaces in existing drivers. Add an interface for other subsystems to find and allocate chunks of P2P memory as necessary to facilitate transfers between two PCI peers: struct pci_dev *pci_p2pmem_find[_many](); int pci_p2pdma_distance[_many](); void *pci_alloc_p2pmem(); The new interface requires a driver to collect a list of client devices involved in the transaction then call pci_p2pmem_find() to obtain any suitable P2P memory. Alternatively, if the caller knows a device which provides P2P memory, they can use pci_p2pdma_distance() to determine if it is usable. With a suitable p2pmem device, memory can then be allocated with pci_alloc_p2pmem() for use in DMA transactions. Depending on hardware, using peer-to-peer memory may reduce the bandwidth of the transfer but can significantly reduce pressure on system memory. This may be desirable in many cases: for example a system could be designed with a small CPU connected to a PCIe switch by a small number of lanes which would maximize the number of lanes available to connect to NVMe devices. The code is designed to only utilize the p2pmem device if all the devices involved in a transfer are behind the same PCI bridge. This is because we have no way of knowing whether peer-to-peer routing between PCIe Root Ports is supported (PCIe r4.0, sec 1.3.1). Additionally, the benefits of P2P transfers that go through the RC is limited to only reducing DRAM usage and, in some cases, coding convenience. The PCI-SIG may be exploring adding a new capability bit to advertise whether this is possible for future hardware. This commit includes significant rework and feedback from Christoph Hellwig. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> [bhelgaas: fold in fix from Keith Busch <keith.busch@intel.com>: https://lore.kernel.org/linux-pci/20181012155920.15418-1-keith.busch@intel.com, to address comment from Dan Carpenter <dan.carpenter@oracle.com>, fold in https://lore.kernel.org/linux-pci/20181017160510.17926-1-logang@deltatee.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-10-04 21:27:35 +00:00
select GENERIC_ALLOCATOR
help
Enableѕ drivers to do PCI peer-to-peer transactions to and from
BARs that are exposed in other devices that are the part of
the hierarchy where peer-to-peer DMA is guaranteed by the PCI
specification to work (ie. anything below a single PCI bridge).
Many PCIe root complexes do not support P2P transactions and
it's hard to tell which support it at all, so at this time,
P2P DMA transations must be between devices behind the same root
port.
If unsure, say N.
config PCI_LABEL
def_bool y if (DMI || ACPI)
select NLS
config PCI_HYPERV
tristate "Hyper-V PCI Frontend"
depends on X86 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && X86_64
help
The PCI device frontend driver allows the kernel to import arbitrary
PCI devices from a PCI backend to support PCI driver domains.
source "drivers/pci/hotplug/Kconfig"
source "drivers/pci/controller/Kconfig"
source "drivers/pci/endpoint/Kconfig"
MicroSemi Switchtec management interface driver Microsemi's "Switchtec" line of PCI switch devices is already well supported by the kernel with standard PCI switch drivers. However, the Switchtec device advertises a special management endpoint with a separate PCI function address and class code. This endpoint enables some additional functionality which includes: * Packet and Byte Counters * Switch Firmware Upgrades * Event and Error logs * Querying port link status * Custom user firmware commands Add a switchtec kernel module which provides PCI driver that exposes a char device. The char device provides userspace access to this interface through read, write and (optionally) poll calls. A userspace tool and library which utilizes this interface is available at [1]. This tool takes inspiration (and borrows some code) from nvme-cli [2]. The tool is largely complete at this time but additional features may be added in the future. [1] https://github.com/sbates130272/switchtec-user [2] https://github.com/linux-nvme/nvme-cli [Dan Carpenter <dan.carpenter@oracle.com>: don't invert error codes] [Christophe JAILLET <christophe.jaillet@wanadoo.fr>: fix switchtec_dev_open() error handling] Tested-by: Krishna Dhulipala <krishnad@fb.com> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Stephen Bates <stephen.bates@microsemi.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Wei Zhang <wzhang@fb.com> Reviewed-by: Jens Axboe <axboe@fb.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-07 00:30:54 +00:00
source "drivers/pci/switch/Kconfig"
endif