tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0
2#
3# PCI configuration
4#
5
6# select this to offer the PCI prompt
7config HAVE_PCI
8 bool
9
10# select this to unconditionally force on PCI support
11config FORCE_PCI
12 bool
13 select HAVE_PCI
14 select PCI
15
16menuconfig PCI
17 bool "PCI support"
18 depends on HAVE_PCI
19 help
20 This option enables support for the PCI local bus, including
21 support for PCI-X and the foundations for PCI Express support.
22 Say 'Y' here unless you know what you are doing.
23
24if PCI
25
26config PCI_DOMAINS
27 bool
28 depends on PCI
29
30config PCI_DOMAINS_GENERIC
31 bool
32 select PCI_DOMAINS
33
34config PCI_SYSCALL
35 bool
36
37source "drivers/pci/pcie/Kconfig"
38
39config PCI_MSI
40 bool "Message Signaled Interrupts (MSI and MSI-X)"
41 select GENERIC_MSI_IRQ
42 help
43 This allows device drivers to enable MSI (Message Signaled
44 Interrupts). Message Signaled Interrupts enable a device to
45 generate an interrupt using an inbound Memory Write on its
46 PCI bus instead of asserting a device IRQ pin.
47
48 Use of PCI MSI interrupts can be disabled at kernel boot time
49 by using the 'pci=nomsi' option. This disables MSI for the
50 entire system.
51
52 If you don't know what to do here, say Y.
53
54config PCI_MSI_IRQ_DOMAIN
55 def_bool y
56 depends on PCI_MSI
57 select GENERIC_MSI_IRQ_DOMAIN
58
59config PCI_MSI_ARCH_FALLBACKS
60 bool
61
62config PCI_QUIRKS
63 default y
64 bool "Enable PCI quirk workarounds" if EXPERT
65 help
66 This enables workarounds for various PCI chipset bugs/quirks.
67 Disable this only if your target machine is unaffected by PCI
68 quirks.
69
70config PCI_DEBUG
71 bool "PCI Debugging"
72 depends on DEBUG_KERNEL
73 help
74 Say Y here if you want the PCI core to produce a bunch of debug
75 messages to the system log. Select this if you are having a
76 problem with PCI support and want to see more of what is going on.
77
78 When in doubt, say N.
79
80config PCI_REALLOC_ENABLE_AUTO
81 bool "Enable PCI resource re-allocation detection"
82 depends on PCI_IOV
83 help
84 Say Y here if you want the PCI core to detect if PCI resource
85 re-allocation needs to be enabled. You can always use pci=realloc=on
86 or pci=realloc=off to override it. It will automatically
87 re-allocate PCI resources if SR-IOV BARs have not been allocated by
88 the BIOS.
89
90 When in doubt, say N.
91
92config PCI_STUB
93 tristate "PCI Stub driver"
94 help
95 Say Y or M here if you want be able to reserve a PCI device
96 when it is going to be assigned to a guest operating system.
97
98 When in doubt, say N.
99
100config PCI_PF_STUB
101 tristate "PCI PF Stub driver"
102 depends on PCI_IOV
103 help
104 Say Y or M here if you want to enable support for devices that
105 require SR-IOV support, while at the same time the PF (Physical
106 Function) itself is not providing any actual services on the
107 host itself such as storage or networking.
108
109 When in doubt, say N.
110
111config XEN_PCIDEV_FRONTEND
112 tristate "Xen PCI Frontend"
113 depends on XEN_PV
114 select PCI_XEN
115 select XEN_XENBUS_FRONTEND
116 default y
117 help
118 The PCI device frontend driver allows the kernel to import arbitrary
119 PCI devices from a PCI backend to support PCI driver domains.
120
121config PCI_ATS
122 bool
123
124config PCI_DOE
125 bool
126
127config PCI_ECAM
128 bool
129
130config PCI_LOCKLESS_CONFIG
131 bool
132
133config PCI_BRIDGE_EMUL
134 bool
135
136config PCI_IOV
137 bool "PCI IOV support"
138 select PCI_ATS
139 help
140 I/O Virtualization is a PCI feature supported by some devices
141 which allows them to create virtual devices which share their
142 physical resources.
143
144 If unsure, say N.
145
146config PCI_PRI
147 bool "PCI PRI support"
148 select PCI_ATS
149 help
150 PRI is the PCI Page Request Interface. It allows PCI devices that are
151 behind an IOMMU to recover from page faults.
152
153 If unsure, say N.
154
155config PCI_PASID
156 bool "PCI PASID support"
157 select PCI_ATS
158 help
159 Process Address Space Identifiers (PASIDs) can be used by PCI devices
160 to access more than one IO address space at the same time. To make
161 use of this feature an IOMMU is required which also supports PASIDs.
162 Select this option if you have such an IOMMU and want to compile the
163 driver for it into your kernel.
164
165 If unsure, say N.
166
167config PCI_P2PDMA
168 bool "PCI peer-to-peer transfer support"
169 depends on ZONE_DEVICE
170 #
171 # The need for the scatterlist DMA bus address flag means PCI P2PDMA
172 # requires 64bit
173 #
174 depends on 64BIT
175 select GENERIC_ALLOCATOR
176 help
177 Enableѕ drivers to do PCI peer-to-peer transactions to and from
178 BARs that are exposed in other devices that are the part of
179 the hierarchy where peer-to-peer DMA is guaranteed by the PCI
180 specification to work (ie. anything below a single PCI bridge).
181
182 Many PCIe root complexes do not support P2P transactions and
183 it's hard to tell which support it at all, so at this time,
184 P2P DMA transactions must be between devices behind the same root
185 port.
186
187 If unsure, say N.
188
189config PCI_LABEL
190 def_bool y if (DMI || ACPI)
191 select NLS
192
193config PCI_HYPERV
194 tristate "Hyper-V PCI Frontend"
195 depends on ((X86 && X86_64) || ARM64) && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && SYSFS
196 select PCI_HYPERV_INTERFACE
197 help
198 The PCI device frontend driver allows the kernel to import arbitrary
199 PCI devices from a PCI backend to support PCI driver domains.
200
201choice
202 prompt "PCI Express hierarchy optimization setting"
203 default PCIE_BUS_DEFAULT
204 depends on PCI && EXPERT
205 help
206 MPS (Max Payload Size) and MRRS (Max Read Request Size) are PCIe
207 device parameters that affect performance and the ability to
208 support hotplug and peer-to-peer DMA.
209
210 The following choices set the MPS and MRRS optimization strategy
211 at compile-time. The choices are the same as those offered for
212 the kernel command-line parameter 'pci', i.e.,
213 'pci=pcie_bus_tune_off', 'pci=pcie_bus_safe',
214 'pci=pcie_bus_perf', and 'pci=pcie_bus_peer2peer'.
215
216 This is a compile-time setting and can be overridden by the above
217 command-line parameters. If unsure, choose PCIE_BUS_DEFAULT.
218
219config PCIE_BUS_TUNE_OFF
220 bool "Tune Off"
221 depends on PCI
222 help
223 Use the BIOS defaults; don't touch MPS at all. This is the same
224 as booting with 'pci=pcie_bus_tune_off'.
225
226config PCIE_BUS_DEFAULT
227 bool "Default"
228 depends on PCI
229 help
230 Default choice; ensure that the MPS matches upstream bridge.
231
232config PCIE_BUS_SAFE
233 bool "Safe"
234 depends on PCI
235 help
236 Use largest MPS that boot-time devices support. If you have a
237 closed system with no possibility of adding new devices, this
238 will use the largest MPS that's supported by all devices. This
239 is the same as booting with 'pci=pcie_bus_safe'.
240
241config PCIE_BUS_PERFORMANCE
242 bool "Performance"
243 depends on PCI
244 help
245 Use MPS and MRRS for best performance. Ensure that a given
246 device's MPS is no larger than its parent MPS, which allows us to
247 keep all switches/bridges to the max MPS supported by their
248 parent. This is the same as booting with 'pci=pcie_bus_perf'.
249
250config PCIE_BUS_PEER2PEER
251 bool "Peer2peer"
252 depends on PCI
253 help
254 Set MPS = 128 for all devices. MPS configuration effected by the
255 other options could cause the MPS on one root port to be
256 different than that of the MPS on another, which may cause
257 hot-added devices or peer-to-peer DMA to fail. Set MPS to the
258 smallest possible value (128B) system-wide to avoid these issues.
259 This is the same as booting with 'pci=pcie_bus_peer2peer'.
260
261endchoice
262
263config VGA_ARB
264 bool "VGA Arbitration" if EXPERT
265 default y
266 depends on (PCI && !S390)
267 help
268 Some "legacy" VGA devices implemented on PCI typically have the same
269 hard-decoded addresses as they did on ISA. When multiple PCI devices
270 are accessed at same time they need some kind of coordination. Please
271 see Documentation/gpu/vgaarbiter.rst for more details. Select this to
272 enable VGA arbiter.
273
274config VGA_ARB_MAX_GPUS
275 int "Maximum number of GPUs"
276 default 16
277 depends on VGA_ARB
278 help
279 Reserves space in the kernel to maintain resource locking for
280 multiple GPUS. The overhead for each GPU is very small.
281
282source "drivers/pci/hotplug/Kconfig"
283source "drivers/pci/controller/Kconfig"
284source "drivers/pci/endpoint/Kconfig"
285source "drivers/pci/switch/Kconfig"
286
287endif