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ec8f24b7 | 1 | # SPDX-License-Identifier: GPL-2.0-only |
04851772 MF |
2 | menu "EFI (Extensible Firmware Interface) Support" |
3 | depends on EFI | |
4 | ||
5 | config EFI_VARS | |
6 | tristate "EFI Variable Support via sysfs" | |
963fabf3 | 7 | depends on EFI && (X86 || IA64) |
04851772 MF |
8 | default n |
9 | help | |
10 | If you say Y here, you are able to get EFI (Extensible Firmware | |
11 | Interface) variable information via sysfs. You may read, | |
12 | write, create, and destroy EFI variables through this interface. | |
963fabf3 AB |
13 | Note that this driver is only retained for compatibility with |
14 | legacy users: new users should use the efivarfs filesystem | |
15 | instead. | |
04851772 | 16 | |
3846c158 PJ |
17 | config EFI_ESRT |
18 | bool | |
19 | depends on EFI && !IA64 | |
20 | default y | |
21 | ||
04851772 MF |
22 | config EFI_VARS_PSTORE |
23 | tristate "Register efivars backend for pstore" | |
232f4eb6 | 24 | depends on PSTORE |
04851772 MF |
25 | default y |
26 | help | |
27 | Say Y here to enable use efivars as a backend to pstore. This | |
28 | will allow writing console messages, crash dumps, or anything | |
29 | else supported by pstore to EFI variables. | |
30 | ||
31 | config EFI_VARS_PSTORE_DEFAULT_DISABLE | |
32 | bool "Disable using efivars as a pstore backend by default" | |
33 | depends on EFI_VARS_PSTORE | |
34 | default n | |
35 | help | |
36 | Saying Y here will disable the use of efivars as a storage | |
37 | backend for pstore by default. This setting can be overridden | |
38 | using the efivars module's pstore_disable parameter. | |
39 | ||
926172d4 DY |
40 | config EFI_RUNTIME_MAP |
41 | bool "Export efi runtime maps to sysfs" | |
2965faa5 | 42 | depends on X86 && EFI && KEXEC_CORE |
926172d4 DY |
43 | default y |
44 | help | |
45 | Export efi runtime memory maps to /sys/firmware/efi/runtime-map. | |
46 | That memory map is used for example by kexec to set up efi virtual | |
47 | mapping the 2nd kernel, but can also be used for debugging purposes. | |
48 | ||
49 | See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map. | |
50 | ||
0f96a99d TI |
51 | config EFI_FAKE_MEMMAP |
52 | bool "Enable EFI fake memory map" | |
53 | depends on EFI && X86 | |
54 | default n | |
55 | help | |
56 | Saying Y here will enable "efi_fake_mem" boot option. | |
57 | By specifying this parameter, you can add arbitrary attribute | |
58 | to specific memory range by updating original (firmware provided) | |
59 | EFI memmap. | |
60 | This is useful for debugging of EFI memmap related feature. | |
61 | e.g. Address Range Mirroring feature. | |
62 | ||
63 | config EFI_MAX_FAKE_MEM | |
64 | int "maximum allowable number of ranges in efi_fake_mem boot option" | |
65 | depends on EFI_FAKE_MEMMAP | |
66 | range 1 128 | |
67 | default 8 | |
68 | help | |
69 | Maximum allowable number of ranges in efi_fake_mem boot option. | |
70 | Ranges can be set up to this value using comma-separated list. | |
71 | The default value is 8. | |
72 | ||
b617c526 DW |
73 | config EFI_SOFT_RESERVE |
74 | bool "Reserve EFI Specific Purpose Memory" | |
75 | depends on EFI && EFI_STUB && ACPI_HMAT | |
76 | default ACPI_HMAT | |
77 | help | |
78 | On systems that have mixed performance classes of memory EFI | |
79 | may indicate specific purpose memory with an attribute (See | |
80 | EFI_MEMORY_SP in UEFI 2.8). A memory range tagged with this | |
81 | attribute may have unique performance characteristics compared | |
82 | to the system's general purpose "System RAM" pool. On the | |
83 | expectation that such memory has application specific usage, | |
84 | and its base EFI memory type is "conventional" answer Y to | |
85 | arrange for the kernel to reserve it as a "Soft Reserved" | |
86 | resource, and set aside for direct-access (device-dax) by | |
87 | default. The memory range can later be optionally assigned to | |
88 | the page allocator by system administrator policy via the | |
89 | device-dax kmem facility. Say N to have the kernel treat this | |
90 | memory as "System RAM" by default. | |
91 | ||
92 | If unsure, say Y. | |
93 | ||
0302f71c MS |
94 | config EFI_PARAMS_FROM_FDT |
95 | bool | |
96 | help | |
97 | Select this config option from the architecture Kconfig if | |
98 | the EFI runtime support gets system table address, memory | |
99 | map address, and other parameters from the device tree. | |
100 | ||
022ee6c5 AB |
101 | config EFI_RUNTIME_WRAPPERS |
102 | bool | |
103 | ||
2e0eb483 | 104 | config EFI_GENERIC_STUB |
f4f75ad5 AB |
105 | bool |
106 | ||
3d7ee348 AB |
107 | config EFI_ARMSTUB_DTB_LOADER |
108 | bool "Enable the DTB loader" | |
d7071743 | 109 | depends on EFI_GENERIC_STUB && !RISCV |
d3109593 | 110 | default y |
3d7ee348 AB |
111 | help |
112 | Select this config option to add support for the dtb= command | |
113 | line parameter, allowing a device tree blob to be loaded into | |
114 | memory from the EFI System Partition by the stub. | |
115 | ||
d3109593 SB |
116 | If the device tree is provided by the platform or by |
117 | the bootloader this option may not be needed. | |
118 | But, for various development reasons and to maintain existing | |
119 | functionality for bootloaders that do not have such support | |
120 | this option is necessary. | |
3d7ee348 | 121 | |
cf6b8366 | 122 | config EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER |
4da0b2b7 AB |
123 | bool "Enable the command line initrd loader" if !X86 |
124 | depends on EFI_STUB && (EFI_GENERIC_STUB || X86) | |
6edcf9dc | 125 | default y if X86 |
d7071743 | 126 | depends on !RISCV |
cf6b8366 AB |
127 | help |
128 | Select this config option to add support for the initrd= command | |
129 | line parameter, allowing an initrd that resides on the same volume | |
130 | as the kernel image to be loaded into memory. | |
131 | ||
132 | This method is deprecated. | |
133 | ||
06f7d4a1 CJ |
134 | config EFI_BOOTLOADER_CONTROL |
135 | tristate "EFI Bootloader Control" | |
06f7d4a1 | 136 | default n |
a7f7f624 | 137 | help |
06f7d4a1 CJ |
138 | This module installs a reboot hook, such that if reboot() is |
139 | invoked with a string argument NNN, "NNN" is copied to the | |
140 | "LoaderEntryOneShot" EFI variable, to be read by the | |
141 | bootloader. If the string matches one of the boot labels | |
142 | defined in its configuration, the bootloader will boot once | |
143 | to that label. The "LoaderEntryRebootReason" EFI variable is | |
144 | set with the reboot reason: "reboot" or "shutdown". The | |
145 | bootloader reads this reboot reason and takes particular | |
146 | action according to its policy. | |
147 | ||
65117f1a KHL |
148 | config EFI_CAPSULE_LOADER |
149 | tristate "EFI capsule loader" | |
150 | depends on EFI | |
151 | help | |
152 | This option exposes a loader interface "/dev/efi_capsule_loader" for | |
153 | users to load EFI capsules. This driver requires working runtime | |
154 | capsule support in the firmware, which many OEMs do not provide. | |
155 | ||
156 | Most users should say N. | |
157 | ||
2959c95d | 158 | config EFI_CAPSULE_QUIRK_QUARK_CSH |
1ae83c5c | 159 | bool "Add support for Quark capsules with non-standard headers" |
2959c95d JK |
160 | depends on X86 && !64BIT |
161 | select EFI_CAPSULE_LOADER | |
162 | default y | |
163 | help | |
164 | Add support for processing Quark X1000 EFI capsules, whose header | |
165 | layout deviates from the layout mandated by the UEFI specification. | |
166 | ||
ff6301da IH |
167 | config EFI_TEST |
168 | tristate "EFI Runtime Service Tests Support" | |
169 | depends on EFI | |
170 | default n | |
171 | help | |
172 | This driver uses the efi.<service> function pointers directly instead | |
173 | of going through the efivar API, because it is not trying to test the | |
174 | kernel subsystem, just for testing the UEFI runtime service | |
175 | interfaces which are provided by the firmware. This driver is used | |
176 | by the Firmware Test Suite (FWTS) for testing the UEFI runtime | |
177 | interfaces readiness of the firmware. | |
178 | Details for FWTS are available from: | |
179 | <https://wiki.ubuntu.com/FirmwareTestSuite> | |
180 | ||
181 | Say Y here to enable the runtime services support via /dev/efi_test. | |
182 | If unsure, say N. | |
183 | ||
58c5475a LW |
184 | config APPLE_PROPERTIES |
185 | bool "Apple Device Properties" | |
186 | depends on EFI_STUB && X86 | |
187 | select EFI_DEV_PATH_PARSER | |
188 | select UCS2_STRING | |
189 | help | |
190 | Retrieve properties from EFI on Apple Macs and assign them to | |
191 | devices, allowing for improved support of Apple hardware. | |
192 | Properties that would otherwise be missing include the | |
193 | Thunderbolt Device ROM and GPU configuration data. | |
194 | ||
195 | If unsure, say Y if you have a Mac. Otherwise N. | |
196 | ||
ccc829ba MG |
197 | config RESET_ATTACK_MITIGATION |
198 | bool "Reset memory attack mitigation" | |
199 | depends on EFI_STUB | |
200 | help | |
201 | Request that the firmware clear the contents of RAM after a reboot | |
202 | using the TCG Platform Reset Attack Mitigation specification. This | |
203 | protects against an attacker forcibly rebooting the system while it | |
204 | still contains secrets in RAM, booting another OS and extracting the | |
a5c03c31 MG |
205 | secrets. This should only be enabled when userland is configured to |
206 | clear the MemoryOverwriteRequest flag on clean shutdown after secrets | |
207 | have been evicted, since otherwise it will trigger even on clean | |
208 | reboots. | |
ccc829ba | 209 | |
1c5fecb6 N |
210 | config EFI_RCI2_TABLE |
211 | bool "EFI Runtime Configuration Interface Table Version 2 Support" | |
0b6b30c6 | 212 | depends on X86 || COMPILE_TEST |
1c5fecb6 N |
213 | help |
214 | Displays the content of the Runtime Configuration Interface | |
215 | Table version 2 on Dell EMC PowerEdge systems as a binary | |
216 | attribute 'rci2' under /sys/firmware/efi/tables directory. | |
217 | ||
218 | RCI2 table contains BIOS HII in XML format and is used to populate | |
219 | BIOS setup page in Dell EMC OpenManage Server Administrator tool. | |
220 | The BIOS setup page contains BIOS tokens which can be configured. | |
221 | ||
222 | Say Y here for Dell EMC PowerEdge systems. | |
223 | ||
4444f854 MG |
224 | config EFI_DISABLE_PCI_DMA |
225 | bool "Clear Busmaster bit on PCI bridges during ExitBootServices()" | |
226 | help | |
227 | Disable the busmaster bit in the control register on all PCI bridges | |
228 | while calling ExitBootServices() and passing control to the runtime | |
229 | kernel. System firmware may configure the IOMMU to prevent malicious | |
230 | PCI devices from being able to attack the OS via DMA. However, since | |
231 | firmware can't guarantee that the OS is IOMMU-aware, it will tear | |
232 | down IOMMU configuration when ExitBootServices() is called. This | |
233 | leaves a window between where a hostile device could still cause | |
234 | damage before Linux configures the IOMMU again. | |
235 | ||
236 | If you say Y here, the EFI stub will clear the busmaster bit on all | |
237 | PCI bridges before ExitBootServices() is called. This will prevent | |
238 | any malicious PCI devices from being able to perform DMA until the | |
239 | kernel reenables busmastering after configuring the IOMMU. | |
240 | ||
241 | This option will cause failures with some poorly behaved hardware | |
242 | and should not be enabled without testing. The kernel commandline | |
243 | options "efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma" | |
244 | may be used to override this option. | |
245 | ||
04851772 | 246 | endmenu |
fce7d3bf | 247 | |
f0df68d5 HG |
248 | config EFI_EMBEDDED_FIRMWARE |
249 | bool | |
250 | depends on EFI | |
251 | select CRYPTO_LIB_SHA256 | |
252 | ||
fce7d3bf JB |
253 | config UEFI_CPER |
254 | bool | |
46cd4b75 | 255 | |
c6d8c8ef TB |
256 | config UEFI_CPER_ARM |
257 | bool | |
258 | depends on UEFI_CPER && ( ARM || ARM64 ) | |
259 | default y | |
260 | ||
f9e1bdb9 YG |
261 | config UEFI_CPER_X86 |
262 | bool | |
263 | depends on UEFI_CPER && X86 | |
264 | default y | |
265 | ||
46cd4b75 LW |
266 | config EFI_DEV_PATH_PARSER |
267 | bool | |
268 | depends on ACPI | |
269 | default n | |
69c1f396 AB |
270 | |
271 | config EFI_EARLYCON | |
272 | def_bool y | |
273 | depends on SERIAL_EARLYCON && !ARM && !IA64 | |
274 | select FONT_SUPPORT | |
275 | select ARCH_USE_MEMREMAP_PROT | |
435d1a47 PJ |
276 | |
277 | config EFI_CUSTOM_SSDT_OVERLAYS | |
278 | bool "Load custom ACPI SSDT overlay from an EFI variable" | |
5ee70cd6 | 279 | depends on EFI && ACPI |
435d1a47 PJ |
280 | default ACPI_TABLE_UPGRADE |
281 | help | |
282 | Allow loading of an ACPI SSDT overlay from an EFI variable specified | |
283 | by a kernel command line option. | |
284 | ||
285 | See Documentation/admin-guide/acpi/ssdt-overlays.rst for more | |
286 | information. |