1# SPDX-License-Identifier: GPL-2.0
2menu "Generic Driver Options"
3
4config AUXILIARY_BUS
5	bool
6
7config UEVENT_HELPER
8	bool "Support for uevent helper"
9	help
10	  The uevent helper program is forked by the kernel for
11	  every uevent.
12	  Before the switch to the netlink-based uevent source, this was
13	  used to hook hotplug scripts into kernel device events. It
14	  usually pointed to a shell script at /sbin/hotplug.
15	  This should not be used today, because usual systems create
16	  many events at bootup or device discovery in a very short time
17	  frame. One forked process per event can create so many processes
18	  that it creates a high system load, or on smaller systems
19	  it is known to create out-of-memory situations during bootup.
20
21config UEVENT_HELPER_PATH
22	string "path to uevent helper"
23	depends on UEVENT_HELPER
24	default ""
25	help
26	  To disable user space helper program execution at by default
27	  specify an empty string here. This setting can still be altered
28	  via /proc/sys/kernel/hotplug or via /sys/kernel/uevent_helper
29	  later at runtime.
30
31config DEVTMPFS
32	bool "Maintain a devtmpfs filesystem to mount at /dev"
33	help
34	  This creates a tmpfs/ramfs filesystem instance early at bootup.
35	  In this filesystem, the kernel driver core maintains device
36	  nodes with their default names and permissions for all
37	  registered devices with an assigned major/minor number.
38	  Userspace can modify the filesystem content as needed, add
39	  symlinks, and apply needed permissions.
40	  It provides a fully functional /dev directory, where usually
41	  udev runs on top, managing permissions and adding meaningful
42	  symlinks.
43	  In very limited environments, it may provide a sufficient
44	  functional /dev without any further help. It also allows simple
45	  rescue systems, and reliably handles dynamic major/minor numbers.
46
47	  Notice: if CONFIG_TMPFS isn't enabled, the simpler ramfs
48	  file system will be used instead.
49
50config DEVTMPFS_MOUNT
51	bool "Automount devtmpfs at /dev, after the kernel mounted the rootfs"
52	depends on DEVTMPFS
53	help
54	  This will instruct the kernel to automatically mount the
55	  devtmpfs filesystem at /dev, directly after the kernel has
56	  mounted the root filesystem. The behavior can be overridden
57	  with the commandline parameter: devtmpfs.mount=0|1.
58	  This option does not affect initramfs based booting, here
59	  the devtmpfs filesystem always needs to be mounted manually
60	  after the rootfs is mounted.
61	  With this option enabled, it allows to bring up a system in
62	  rescue mode with init=/bin/sh, even when the /dev directory
63	  on the rootfs is completely empty.
64
65config STANDALONE
66	bool "Select only drivers that don't need compile-time external firmware"
67	default y
68	help
69	  Select this option if you don't have magic firmware for drivers that
70	  need it.
71
72	  If unsure, say Y.
73
74config PREVENT_FIRMWARE_BUILD
75	bool "Disable drivers features which enable custom firmware building"
76	default y
77	help
78	  Say yes to disable driver features which enable building a custom
79	  driver firmware at kernel build time. These drivers do not use the
80	  kernel firmware API to load firmware (CONFIG_FW_LOADER), instead they
81	  use their own custom loading mechanism. The required firmware is
82	  usually shipped with the driver, building the driver firmware
83	  should only be needed if you have an updated firmware source.
84
85	  Firmware should not be being built as part of kernel, these days
86	  you should always prevent this and say Y here. There are only two
87	  old drivers which enable building of its firmware at kernel build
88	  time:
89
90	    o CONFIG_WANXL through CONFIG_WANXL_BUILD_FIRMWARE
91	    o CONFIG_SCSI_AIC79XX through CONFIG_AIC79XX_BUILD_FIRMWARE
92
93source "drivers/base/firmware_loader/Kconfig"
94
95config WANT_DEV_COREDUMP
96	bool
97	help
98	  Drivers should "select" this option if they desire to use the
99	  device coredump mechanism.
100
101config ALLOW_DEV_COREDUMP
102	bool "Allow device coredump" if EXPERT
103	default y
104	help
105	  This option controls if the device coredump mechanism is available or
106	  not; if disabled, the mechanism will be omitted even if drivers that
107	  can use it are enabled.
108	  Say 'N' for more sensitive systems or systems that don't want
109	  to ever access the information to not have the code, nor keep any
110	  data.
111
112	  If unsure, say Y.
113
114config DEV_COREDUMP
115	bool
116	default y if WANT_DEV_COREDUMP
117	depends on ALLOW_DEV_COREDUMP
118
119config DEBUG_DRIVER
120	bool "Driver Core verbose debug messages"
121	depends on DEBUG_KERNEL
122	help
123	  Say Y here if you want the Driver core to produce a bunch of
124	  debug messages to the system log. Select this if you are having a
125	  problem with the driver core and want to see more of what is
126	  going on.
127
128	  If you are unsure about this, say N here.
129
130config DEBUG_DEVRES
131	bool "Managed device resources verbose debug messages"
132	depends on DEBUG_KERNEL
133	help
134	  This option enables kernel parameter devres.log. If set to
135	  non-zero, devres debug messages are printed. Select this if
136	  you are having a problem with devres or want to debug
137	  resource management for a managed device. devres.log can be
138	  switched on and off from sysfs node.
139
140	  If you are unsure about this, Say N here.
141
142config DEBUG_TEST_DRIVER_REMOVE
143	bool "Test driver remove calls during probe (UNSTABLE)"
144	depends on DEBUG_KERNEL
145	help
146	  Say Y here if you want the Driver core to test driver remove functions
147	  by calling probe, remove, probe. This tests the remove path without
148	  having to unbind the driver or unload the driver module.
149
150	  This option is expected to find errors and may render your system
151	  unusable. You should say N here unless you are explicitly looking to
152	  test this functionality.
153
154config PM_QOS_KUNIT_TEST
155	bool "KUnit Test for PM QoS features" if !KUNIT_ALL_TESTS
156	depends on KUNIT=y
157	default KUNIT_ALL_TESTS
158
159config HMEM_REPORTING
160	bool
161	default n
162	depends on NUMA
163	help
164	  Enable reporting for heterogeneous memory access attributes under
165	  their non-uniform memory nodes.
166
167source "drivers/base/test/Kconfig"
168
169config SYS_HYPERVISOR
170	bool
171	default n
172
173config GENERIC_CPU_DEVICES
174	bool
175	default n
176
177config GENERIC_CPU_AUTOPROBE
178	bool
179
180config GENERIC_CPU_VULNERABILITIES
181	bool
182
183config SOC_BUS
184	bool
185	select GLOB
186
187source "drivers/base/regmap/Kconfig"
188
189config DMA_SHARED_BUFFER
190	bool
191	default n
192	select IRQ_WORK
193	help
194	  This option enables the framework for buffer-sharing between
195	  multiple drivers. A buffer is associated with a file using driver
196	  APIs extension; the file's descriptor can then be passed on to other
197	  driver.
198
199config DMA_FENCE_TRACE
200	bool "Enable verbose DMA_FENCE_TRACE messages"
201	depends on DMA_SHARED_BUFFER
202	help
203	  Enable the DMA_FENCE_TRACE printks. This will add extra
204	  spam to the console log, but will make it easier to diagnose
205	  lockup related problems for dma-buffers shared across multiple
206	  devices.
207
208config GENERIC_ARCH_TOPOLOGY
209	bool
210	help
211	  Enable support for architectures common topology code: e.g., parsing
212	  CPU capacity information from DT, usage of such information for
213	  appropriate scaling, sysfs interface for reading capacity values at
214	  runtime.
215
216config GENERIC_ARCH_NUMA
217	bool
218	help
219	  Enable support for generic NUMA implementation. Currently, RISC-V
220	  and ARM64 use it.
221
222endmenu
223