1 # SPDX-License-Identifier: GPL-2.0-only
3 # For a description of the syntax of this configuration file,
4 # see Documentation/kbuild/kconfig-language.rst.
15 select ARCH_CLOCKSOURCE_INIT
16 select ARCH_SUPPORTS_ATOMIC_RMW
17 select ARCH_HAS_BINFMT_FLAT
18 select ARCH_HAS_DEBUG_VM_PGTABLE
19 select ARCH_HAS_DEBUG_VIRTUAL if MMU
20 select ARCH_HAS_DEBUG_WX
21 select ARCH_HAS_GCOV_PROFILE_ALL
22 select ARCH_HAS_GIGANTIC_PAGE
24 select ARCH_HAS_MMIOWB
25 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
26 select ARCH_HAS_PTE_SPECIAL
27 select ARCH_HAS_SET_DIRECT_MAP
28 select ARCH_HAS_SET_MEMORY
29 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
30 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
31 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
32 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
33 select ARCH_WANT_FRAME_POINTERS
34 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
35 select CLONE_BACKWARDS
36 select CLINT_TIMER if !MMU
39 select GENERIC_ARCH_TOPOLOGY
40 select GENERIC_ATOMIC64 if !64BIT
41 select GENERIC_CLOCKEVENTS
42 select GENERIC_EARLY_IOREMAP
43 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
44 select GENERIC_IOREMAP
45 select GENERIC_IRQ_MULTI_HANDLER
46 select GENERIC_IRQ_SHOW
47 select GENERIC_PCI_IOMAP
48 select GENERIC_PTDUMP if MMU
49 select GENERIC_SCHED_CLOCK
50 select GENERIC_SMP_IDLE_THREAD
51 select GENERIC_STRNCPY_FROM_USER if MMU
52 select GENERIC_STRNLEN_USER if MMU
53 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
54 select HANDLE_DOMAIN_IRQ
55 select HAVE_ARCH_AUDITSYSCALL
56 select HAVE_ARCH_JUMP_LABEL
57 select HAVE_ARCH_JUMP_LABEL_RELATIVE
58 select HAVE_ARCH_KASAN if MMU && 64BIT
60 select HAVE_ARCH_KGDB_QXFER_PKT
61 select HAVE_ARCH_MMAP_RND_BITS if MMU
62 select HAVE_ARCH_SECCOMP_FILTER
63 select HAVE_ARCH_TRACEHOOK
64 select HAVE_ASM_MODVERSIONS
65 select HAVE_CONTEXT_TRACKING
66 select HAVE_DEBUG_KMEMLEAK
67 select HAVE_DMA_CONTIGUOUS if MMU
68 select HAVE_EBPF_JIT if MMU
69 select HAVE_FUTEX_CMPXCHG if FUTEX
70 select HAVE_GCC_PLUGINS
71 select HAVE_GENERIC_VDSO if MMU && 64BIT
73 select HAVE_PERF_EVENTS
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_STACKPROTECTOR
77 select HAVE_SYSCALL_TRACEPOINTS
79 select MODULES_USE_ELF_RELA if MODULES
80 select MODULE_SECTIONS if MODULES
82 select OF_EARLY_FLATTREE
84 select PCI_DOMAINS_GENERIC if PCI
87 select RISCV_TIMER if RISCV_SBI
89 select SYSCTL_EXCEPTION_TRACE
90 select THREAD_INFO_IN_TASK
91 select UACCESS_MEMCPY if !MMU
93 config ARCH_MMAP_RND_BITS_MIN
97 # max bits determined by the following formula:
98 # VA_BITS - PAGE_SHIFT - 3
99 config ARCH_MMAP_RND_BITS_MAX
100 default 24 if 64BIT # SV39 based
103 # set if we run in machine mode, cleared if we run in supervisor mode
108 # set if we are running in S-mode and can use SBI calls
111 depends on !RISCV_M_MODE
115 bool "MMU-based Paged Memory Management Support"
118 Select if you want MMU-based virtualised addressing space
119 support by paged memory management. If unsure, say 'Y'.
137 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
138 default 0x80000000 if 64BIT && !MMU
139 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
140 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
142 config KASAN_SHADOW_OFFSET
144 depends on KASAN_GENERIC
145 default 0xdfffffc800000000 if 64BIT
146 default 0xffffffff if 32BIT
148 config ARCH_FLATMEM_ENABLE
151 config ARCH_SPARSEMEM_ENABLE
154 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
155 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
157 config ARCH_SELECT_MEMORY_MODEL
158 def_bool ARCH_SPARSEMEM_ENABLE
160 config ARCH_WANT_GENERAL_HUGETLB
163 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
166 config SYS_SUPPORTS_HUGETLBFS
170 config STACKTRACE_SUPPORT
173 config TRACE_IRQFLAGS_SUPPORT
179 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
181 config GENERIC_BUG_RELATIVE_POINTERS
184 config GENERIC_CALIBRATE_DELAY
190 config GENERIC_HWEIGHT
193 config FIX_EARLYCON_MEM
196 config PGTABLE_LEVELS
201 config LOCKDEP_SUPPORT
204 source "arch/riscv/Kconfig.socs"
212 This selects the base ISA that this kernel will target and must match
218 select GENERIC_LIB_ASHLDI3
219 select GENERIC_LIB_ASHRDI3
220 select GENERIC_LIB_LSHRDI3
221 select GENERIC_LIB_UCMPDI2
227 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
228 select HAVE_DYNAMIC_FTRACE if MMU
229 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
230 select HAVE_FTRACE_MCOUNT_RECORD
231 select HAVE_FUNCTION_GRAPH_TRACER
232 select HAVE_FUNCTION_TRACER
233 select SWIOTLB if MMU
237 # We must be able to map all physical memory into the kernel, but the compiler
238 # is still a bit more efficient when generating code if it's setup in a manner
239 # such that it can only map 2GiB of memory.
241 prompt "Kernel Code Model"
242 default CMODEL_MEDLOW if 32BIT
243 default CMODEL_MEDANY if 64BIT
246 bool "medium low code model"
248 bool "medium any code model"
251 config MODULE_SECTIONS
253 select HAVE_MOD_ARCH_SPECIFIC
256 prompt "Maximum Physical Memory"
257 default MAXPHYSMEM_1GB if 32BIT
258 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
259 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
261 config MAXPHYSMEM_1GB
264 config MAXPHYSMEM_2GB
265 depends on 64BIT && CMODEL_MEDLOW
267 config MAXPHYSMEM_128GB
268 depends on 64BIT && CMODEL_MEDANY
274 bool "Symmetric Multi-Processing"
276 This enables support for systems with more than one CPU. If
277 you say N here, the kernel will run on single and
278 multiprocessor machines, but will use only one CPU of a
279 multiprocessor machine. If you say Y here, the kernel will run
280 on many, but not all, single processor machines. On a single
281 processor machine, the kernel will run faster if you say N
284 If you don't know what to do here, say N.
287 int "Maximum number of CPUs (2-32)"
293 bool "Support for hot-pluggable CPUs"
295 select GENERIC_IRQ_MIGRATION
298 Say Y here to experiment with turning CPUs off and on. CPUs
299 can be controlled through /sys/devices/system/cpu.
301 Say N if you want to disable CPU hotplug.
313 bool "Emit compressed instructions when building Linux"
316 Adds "C" to the ISA subsets that the toolchain is allowed to emit
317 when building Linux, which results in compressed instructions in the
320 If you don't know what to do here, say Y.
322 menu "supported PMU type"
323 depends on PERF_EVENTS
325 config RISCV_BASE_PMU
326 bool "Base Performance Monitoring Unit"
329 A base PMU that serves as a reference implementation and has limited
330 feature of perf. It can run on any RISC-V machines so serves as the
331 fallback, but this option can also be disable to reduce kernel size.
335 config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
337 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
338 depends on AS_IS_GNU && AS_VERSION >= 23800
340 Newer binutils versions default to ISA spec version 20191213 which
341 moves some instructions from the I extension to the Zicsr and Zifencei
344 config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
346 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
347 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
348 depends on CC_IS_CLANG && CLANG_VERSION < 170000
350 Certain versions of clang do not support zicsr and zifencei via -march
351 but newer versions of binutils require it for the reasons noted in the
352 help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
353 option causes an older ISA spec compatible with these older versions
354 of clang to be passed to GAS, which has the same result as passing zicsr
355 and zifencei to -march.
361 Say N here if you want to disable all floating-point related procedure
364 If you don't know what to do here, say Y.
368 menu "Kernel features"
370 source "kernel/Kconfig.hz"
373 bool "SBI v0.1 support"
377 This config allows kernel to use SBI v0.1 APIs. This will be
378 deprecated in future once legacy M-mode software are no longer in use.
384 string "Built-in kernel command line"
386 For most platforms, the arguments for the kernel's command line
387 are provided at run-time, during boot. However, there are cases
388 where either no arguments are being provided or the provided
389 arguments are insufficient or even invalid.
391 When that occurs, it is possible to define a built-in command
392 line here and choose how the kernel should use it later on.
395 prompt "Built-in command line usage" if CMDLINE != ""
396 default CMDLINE_FALLBACK
398 Choose how the kernel will handle the provided built-in command
401 config CMDLINE_FALLBACK
402 bool "Use bootloader kernel arguments if available"
404 Use the built-in command line as fallback in case we get nothing
405 during boot. This is the default behaviour.
407 config CMDLINE_EXTEND
408 bool "Extend bootloader kernel arguments"
410 The command-line arguments provided during boot will be
411 appended to the built-in command line. This is useful in
412 cases where the provided arguments are insufficient and
413 you don't want to or cannot modify them.
417 bool "Always use the default kernel command string"
419 Always use the built-in command line, even if we get one during
420 boot. This is useful in case you need to override the provided
421 command line on systems where you don't have or want control
430 bool "UEFI runtime support"
434 select EFI_PARAMS_FROM_FDT
436 select EFI_GENERIC_STUB
437 select EFI_RUNTIME_WRAPPERS
442 This option provides support for runtime services provided
443 by UEFI firmware (such as non-volatile variables, realtime
444 clock, and platform reset). A UEFI stub is also provided to
445 allow the kernel to be booted as an EFI application. This
446 is only useful on systems that have UEFI firmware.
448 config CC_HAVE_STACKPROTECTOR_TLS
449 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
451 config STACKPROTECTOR_PER_TASK
453 depends on !GCC_PLUGIN_RANDSTRUCT
454 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
460 depends on RISCV_M_MODE
463 menu "Power management options"
465 source "kernel/power/Kconfig"
469 source "drivers/firmware/Kconfig"