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_VIRTUAL if MMU
19 select ARCH_HAS_DEBUG_WX
20 select ARCH_HAS_GCOV_PROFILE_ALL
21 select ARCH_HAS_GIGANTIC_PAGE
23 select ARCH_HAS_MMIOWB
24 select ARCH_HAS_PTE_SPECIAL
25 select ARCH_HAS_SET_DIRECT_MAP
26 select ARCH_HAS_SET_MEMORY
27 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
28 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
29 select ARCH_WANT_FRAME_POINTERS
30 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
31 select CLONE_BACKWARDS
34 select GENERIC_ARCH_TOPOLOGY if SMP
35 select GENERIC_ATOMIC64 if !64BIT
36 select GENERIC_CLOCKEVENTS
37 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
38 select GENERIC_IOREMAP
39 select GENERIC_IRQ_MULTI_HANDLER
40 select GENERIC_IRQ_SHOW
41 select GENERIC_PCI_IOMAP
42 select GENERIC_PTDUMP if MMU
43 select GENERIC_SCHED_CLOCK
44 select GENERIC_SMP_IDLE_THREAD
45 select GENERIC_STRNCPY_FROM_USER if MMU
46 select GENERIC_STRNLEN_USER if MMU
47 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
48 select HANDLE_DOMAIN_IRQ
49 select HAVE_ARCH_AUDITSYSCALL
50 select HAVE_ARCH_JUMP_LABEL
51 select HAVE_ARCH_JUMP_LABEL_RELATIVE
52 select HAVE_ARCH_KASAN if MMU && 64BIT
54 select HAVE_ARCH_KGDB_QXFER_PKT
55 select HAVE_ARCH_MMAP_RND_BITS if MMU
56 select HAVE_ARCH_SECCOMP_FILTER
57 select HAVE_ARCH_TRACEHOOK
58 select HAVE_ASM_MODVERSIONS
59 select HAVE_CONTEXT_TRACKING
60 select HAVE_COPY_THREAD_TLS
61 select HAVE_DEBUG_KMEMLEAK
62 select HAVE_DMA_CONTIGUOUS if MMU
63 select HAVE_EBPF_JIT if MMU
64 select HAVE_FUTEX_CMPXCHG if FUTEX
65 select HAVE_GCC_PLUGINS
66 select HAVE_GENERIC_VDSO if MMU && 64BIT
68 select HAVE_PERF_EVENTS
70 select HAVE_PERF_USER_STACK_DUMP
71 select HAVE_STACKPROTECTOR
72 select HAVE_SYSCALL_TRACEPOINTS
74 select MODULES_USE_ELF_RELA if MODULES
75 select MODULE_SECTIONS if MODULES
77 select OF_EARLY_FLATTREE
79 select PCI_DOMAINS_GENERIC if PCI
83 select SPARSEMEM_STATIC if 32BIT
85 select SYSCTL_EXCEPTION_TRACE
86 select THREAD_INFO_IN_TASK
88 config ARCH_MMAP_RND_BITS_MIN
92 # max bits determined by the following formula:
93 # VA_BITS - PAGE_SHIFT - 3
94 config ARCH_MMAP_RND_BITS_MAX
95 default 24 if 64BIT # SV39 based
98 # set if we run in machine mode, cleared if we run in supervisor mode
103 # set if we are running in S-mode and can use SBI calls
106 depends on !RISCV_M_MODE
110 bool "MMU-based Paged Memory Management Support"
113 Select if you want MMU-based virtualised addressing space
114 support by paged memory management. If unsure, say 'Y'.
132 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
133 default 0x80000000 if 64BIT && !MMU
134 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
135 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
137 config ARCH_FLATMEM_ENABLE
140 config ARCH_SPARSEMEM_ENABLE
143 select SPARSEMEM_VMEMMAP_ENABLE
145 config ARCH_SELECT_MEMORY_MODEL
146 def_bool ARCH_SPARSEMEM_ENABLE
148 config ARCH_WANT_GENERAL_HUGETLB
151 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
154 config SYS_SUPPORTS_HUGETLBFS
158 config STACKTRACE_SUPPORT
161 config TRACE_IRQFLAGS_SUPPORT
167 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
169 config GENERIC_BUG_RELATIVE_POINTERS
172 config GENERIC_CALIBRATE_DELAY
178 config GENERIC_HWEIGHT
181 config FIX_EARLYCON_MEM
184 config PGTABLE_LEVELS
189 config LOCKDEP_SUPPORT
192 source "arch/riscv/Kconfig.socs"
200 This selects the base ISA that this kernel will target and must match
206 select GENERIC_LIB_ASHLDI3
207 select GENERIC_LIB_ASHRDI3
208 select GENERIC_LIB_LSHRDI3
209 select GENERIC_LIB_UCMPDI2
215 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
216 select HAVE_DYNAMIC_FTRACE if MMU
217 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
218 select HAVE_FTRACE_MCOUNT_RECORD
219 select HAVE_FUNCTION_GRAPH_TRACER
220 select HAVE_FUNCTION_TRACER
221 select SWIOTLB if MMU
225 # We must be able to map all physical memory into the kernel, but the compiler
226 # is still a bit more efficient when generating code if it's setup in a manner
227 # such that it can only map 2GiB of memory.
229 prompt "Kernel Code Model"
230 default CMODEL_MEDLOW if 32BIT
231 default CMODEL_MEDANY if 64BIT
234 bool "medium low code model"
236 bool "medium any code model"
239 config MODULE_SECTIONS
241 select HAVE_MOD_ARCH_SPECIFIC
244 prompt "Maximum Physical Memory"
245 default MAXPHYSMEM_2GB if 32BIT
246 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
247 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
249 config MAXPHYSMEM_2GB
251 config MAXPHYSMEM_128GB
252 depends on 64BIT && CMODEL_MEDANY
258 bool "Symmetric Multi-Processing"
260 This enables support for systems with more than one CPU. If
261 you say N here, the kernel will run on single and
262 multiprocessor machines, but will use only one CPU of a
263 multiprocessor machine. If you say Y here, the kernel will run
264 on many, but not all, single processor machines. On a single
265 processor machine, the kernel will run faster if you say N
268 If you don't know what to do here, say N.
271 int "Maximum number of CPUs (2-32)"
277 bool "Support for hot-pluggable CPUs"
279 select GENERIC_IRQ_MIGRATION
282 Say Y here to experiment with turning CPUs off and on. CPUs
283 can be controlled through /sys/devices/system/cpu.
285 Say N if you want to disable CPU hotplug.
297 bool "Emit compressed instructions when building Linux"
300 Adds "C" to the ISA subsets that the toolchain is allowed to emit
301 when building Linux, which results in compressed instructions in the
304 If you don't know what to do here, say Y.
306 menu "supported PMU type"
307 depends on PERF_EVENTS
309 config RISCV_BASE_PMU
310 bool "Base Performance Monitoring Unit"
313 A base PMU that serves as a reference implementation and has limited
314 feature of perf. It can run on any RISC-V machines so serves as the
315 fallback, but this option can also be disable to reduce kernel size.
323 Say N here if you want to disable all floating-point related procedure
326 If you don't know what to do here, say Y.
330 menu "Kernel features"
332 source "kernel/Kconfig.hz"
335 bool "Enable seccomp to safely compute untrusted bytecode"
337 This kernel feature is useful for number crunching applications
338 that may need to compute untrusted bytecode during their
339 execution. By using pipes or other transports made available to
340 the process as file descriptors supporting the read/write
341 syscalls, it's possible to isolate those applications in
342 their own address space using seccomp. Once seccomp is
343 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
344 and the task is only allowed to execute a few safe syscalls
345 defined by each seccomp mode.
348 bool "SBI v0.1 support"
352 This config allows kernel to use SBI v0.1 APIs. This will be
353 deprecated in future once legacy M-mode software are no longer in use.
359 string "Built-in kernel command line"
361 For most platforms, the arguments for the kernel's command line
362 are provided at run-time, during boot. However, there are cases
363 where either no arguments are being provided or the provided
364 arguments are insufficient or even invalid.
366 When that occurs, it is possible to define a built-in command
367 line here and choose how the kernel should use it later on.
370 prompt "Built-in command line usage" if CMDLINE != ""
371 default CMDLINE_FALLBACK
373 Choose how the kernel will handle the provided built-in command
376 config CMDLINE_FALLBACK
377 bool "Use bootloader kernel arguments if available"
379 Use the built-in command line as fallback in case we get nothing
380 during boot. This is the default behaviour.
382 config CMDLINE_EXTEND
383 bool "Extend bootloader kernel arguments"
385 The command-line arguments provided during boot will be
386 appended to the built-in command line. This is useful in
387 cases where the provided arguments are insufficient and
388 you don't want to or cannot modify them.
392 bool "Always use the default kernel command string"
394 Always use the built-in command line, even if we get one during
395 boot. This is useful in case you need to override the provided
396 command line on systems where you don't have or want control
405 depends on RISCV_M_MODE
408 menu "Power management options"
410 source "kernel/power/Kconfig"