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_PTE_SPECIAL
26 select ARCH_HAS_SET_DIRECT_MAP
27 select ARCH_HAS_SET_MEMORY
28 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
29 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
30 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
31 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
32 select ARCH_WANT_FRAME_POINTERS
33 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
34 select CLONE_BACKWARDS
37 select GENERIC_ARCH_TOPOLOGY if SMP
38 select GENERIC_ATOMIC64 if !64BIT
39 select GENERIC_CLOCKEVENTS
40 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
41 select GENERIC_IOREMAP
42 select GENERIC_IRQ_MULTI_HANDLER
43 select GENERIC_IRQ_SHOW
44 select GENERIC_PCI_IOMAP
45 select GENERIC_PTDUMP if MMU
46 select GENERIC_SCHED_CLOCK
47 select GENERIC_SMP_IDLE_THREAD
48 select GENERIC_STRNCPY_FROM_USER if MMU
49 select GENERIC_STRNLEN_USER if MMU
50 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
51 select HANDLE_DOMAIN_IRQ
52 select HAVE_ARCH_AUDITSYSCALL
53 select HAVE_ARCH_JUMP_LABEL
54 select HAVE_ARCH_JUMP_LABEL_RELATIVE
55 select HAVE_ARCH_KASAN if MMU && 64BIT
57 select HAVE_ARCH_KGDB_QXFER_PKT
58 select HAVE_ARCH_MMAP_RND_BITS if MMU
59 select HAVE_ARCH_SECCOMP_FILTER
60 select HAVE_ARCH_TRACEHOOK
61 select HAVE_ASM_MODVERSIONS
62 select HAVE_CONTEXT_TRACKING
63 select HAVE_DEBUG_KMEMLEAK
64 select HAVE_DMA_CONTIGUOUS if MMU
65 select HAVE_EBPF_JIT if MMU
66 select HAVE_FUTEX_CMPXCHG if FUTEX
67 select HAVE_GCC_PLUGINS
68 select HAVE_GENERIC_VDSO if MMU && 64BIT
70 select HAVE_PERF_EVENTS
72 select HAVE_PERF_USER_STACK_DUMP
73 select HAVE_STACKPROTECTOR
74 select HAVE_SYSCALL_TRACEPOINTS
76 select MODULES_USE_ELF_RELA if MODULES
77 select MODULE_SECTIONS if MODULES
79 select OF_EARLY_FLATTREE
81 select PCI_DOMAINS_GENERIC if PCI
85 select SPARSEMEM_STATIC if 32BIT
87 select SYSCTL_EXCEPTION_TRACE
88 select THREAD_INFO_IN_TASK
90 config ARCH_MMAP_RND_BITS_MIN
94 # max bits determined by the following formula:
95 # VA_BITS - PAGE_SHIFT - 3
96 config ARCH_MMAP_RND_BITS_MAX
97 default 24 if 64BIT # SV39 based
100 # set if we run in machine mode, cleared if we run in supervisor mode
105 # set if we are running in S-mode and can use SBI calls
108 depends on !RISCV_M_MODE
112 bool "MMU-based Paged Memory Management Support"
115 Select if you want MMU-based virtualised addressing space
116 support by paged memory management. If unsure, say 'Y'.
134 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
135 default 0x80000000 if 64BIT && !MMU
136 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
137 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
139 config ARCH_FLATMEM_ENABLE
142 config ARCH_SPARSEMEM_ENABLE
145 select SPARSEMEM_VMEMMAP_ENABLE
147 config ARCH_SELECT_MEMORY_MODEL
148 def_bool ARCH_SPARSEMEM_ENABLE
150 config ARCH_WANT_GENERAL_HUGETLB
153 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
156 config SYS_SUPPORTS_HUGETLBFS
160 config STACKTRACE_SUPPORT
163 config TRACE_IRQFLAGS_SUPPORT
169 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
171 config GENERIC_BUG_RELATIVE_POINTERS
174 config GENERIC_CALIBRATE_DELAY
180 config GENERIC_HWEIGHT
183 config FIX_EARLYCON_MEM
186 config PGTABLE_LEVELS
191 config LOCKDEP_SUPPORT
194 source "arch/riscv/Kconfig.socs"
202 This selects the base ISA that this kernel will target and must match
208 select GENERIC_LIB_ASHLDI3
209 select GENERIC_LIB_ASHRDI3
210 select GENERIC_LIB_LSHRDI3
211 select GENERIC_LIB_UCMPDI2
217 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
218 select HAVE_DYNAMIC_FTRACE if MMU
219 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
220 select HAVE_FTRACE_MCOUNT_RECORD
221 select HAVE_FUNCTION_GRAPH_TRACER
222 select HAVE_FUNCTION_TRACER
223 select SWIOTLB if MMU
227 # We must be able to map all physical memory into the kernel, but the compiler
228 # is still a bit more efficient when generating code if it's setup in a manner
229 # such that it can only map 2GiB of memory.
231 prompt "Kernel Code Model"
232 default CMODEL_MEDLOW if 32BIT
233 default CMODEL_MEDANY if 64BIT
236 bool "medium low code model"
238 bool "medium any code model"
241 config MODULE_SECTIONS
243 select HAVE_MOD_ARCH_SPECIFIC
246 prompt "Maximum Physical Memory"
247 default MAXPHYSMEM_2GB if 32BIT
248 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
249 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
251 config MAXPHYSMEM_2GB
253 config MAXPHYSMEM_128GB
254 depends on 64BIT && CMODEL_MEDANY
260 bool "Symmetric Multi-Processing"
262 This enables support for systems with more than one CPU. If
263 you say N here, the kernel will run on single and
264 multiprocessor machines, but will use only one CPU of a
265 multiprocessor machine. If you say Y here, the kernel will run
266 on many, but not all, single processor machines. On a single
267 processor machine, the kernel will run faster if you say N
270 If you don't know what to do here, say N.
273 int "Maximum number of CPUs (2-32)"
279 bool "Support for hot-pluggable CPUs"
281 select GENERIC_IRQ_MIGRATION
284 Say Y here to experiment with turning CPUs off and on. CPUs
285 can be controlled through /sys/devices/system/cpu.
287 Say N if you want to disable CPU hotplug.
299 bool "Emit compressed instructions when building Linux"
302 Adds "C" to the ISA subsets that the toolchain is allowed to emit
303 when building Linux, which results in compressed instructions in the
306 If you don't know what to do here, say Y.
308 menu "supported PMU type"
309 depends on PERF_EVENTS
311 config RISCV_BASE_PMU
312 bool "Base Performance Monitoring Unit"
315 A base PMU that serves as a reference implementation and has limited
316 feature of perf. It can run on any RISC-V machines so serves as the
317 fallback, but this option can also be disable to reduce kernel size.
325 Say N here if you want to disable all floating-point related procedure
328 If you don't know what to do here, say Y.
332 menu "Kernel features"
334 source "kernel/Kconfig.hz"
337 bool "Enable seccomp to safely compute untrusted bytecode"
339 This kernel feature is useful for number crunching applications
340 that may need to compute untrusted bytecode during their
341 execution. By using pipes or other transports made available to
342 the process as file descriptors supporting the read/write
343 syscalls, it's possible to isolate those applications in
344 their own address space using seccomp. Once seccomp is
345 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
346 and the task is only allowed to execute a few safe syscalls
347 defined by each seccomp mode.
350 bool "SBI v0.1 support"
354 This config allows kernel to use SBI v0.1 APIs. This will be
355 deprecated in future once legacy M-mode software are no longer in use.
361 string "Built-in kernel command line"
363 For most platforms, the arguments for the kernel's command line
364 are provided at run-time, during boot. However, there are cases
365 where either no arguments are being provided or the provided
366 arguments are insufficient or even invalid.
368 When that occurs, it is possible to define a built-in command
369 line here and choose how the kernel should use it later on.
372 prompt "Built-in command line usage" if CMDLINE != ""
373 default CMDLINE_FALLBACK
375 Choose how the kernel will handle the provided built-in command
378 config CMDLINE_FALLBACK
379 bool "Use bootloader kernel arguments if available"
381 Use the built-in command line as fallback in case we get nothing
382 during boot. This is the default behaviour.
384 config CMDLINE_EXTEND
385 bool "Extend bootloader kernel arguments"
387 The command-line arguments provided during boot will be
388 appended to the built-in command line. This is useful in
389 cases where the provided arguments are insufficient and
390 you don't want to or cannot modify them.
394 bool "Always use the default kernel command string"
396 Always use the built-in command line, even if we get one during
397 boot. This is useful in case you need to override the provided
398 command line on systems where you don't have or want control
407 depends on RISCV_M_MODE
410 menu "Power management options"
412 source "kernel/power/Kconfig"