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_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
30 select ARCH_WANT_FRAME_POINTERS
31 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
32 select CLONE_BACKWARDS
35 select GENERIC_ARCH_TOPOLOGY if SMP
36 select GENERIC_ATOMIC64 if !64BIT
37 select GENERIC_CLOCKEVENTS
38 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
39 select GENERIC_IOREMAP
40 select GENERIC_IRQ_MULTI_HANDLER
41 select GENERIC_IRQ_SHOW
42 select GENERIC_PCI_IOMAP
43 select GENERIC_PTDUMP if MMU
44 select GENERIC_SCHED_CLOCK
45 select GENERIC_SMP_IDLE_THREAD
46 select GENERIC_STRNCPY_FROM_USER if MMU
47 select GENERIC_STRNLEN_USER if MMU
48 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
49 select HANDLE_DOMAIN_IRQ
50 select HAVE_ARCH_AUDITSYSCALL
51 select HAVE_ARCH_JUMP_LABEL
52 select HAVE_ARCH_JUMP_LABEL_RELATIVE
53 select HAVE_ARCH_KASAN if MMU && 64BIT
55 select HAVE_ARCH_KGDB_QXFER_PKT
56 select HAVE_ARCH_MMAP_RND_BITS if MMU
57 select HAVE_ARCH_SECCOMP_FILTER
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_ASM_MODVERSIONS
60 select HAVE_CONTEXT_TRACKING
61 select HAVE_COPY_THREAD_TLS
62 select HAVE_DEBUG_KMEMLEAK
63 select HAVE_DMA_CONTIGUOUS if MMU
64 select HAVE_EBPF_JIT if MMU
65 select HAVE_FUTEX_CMPXCHG if FUTEX
66 select HAVE_GCC_PLUGINS
67 select HAVE_GENERIC_VDSO if MMU && 64BIT
69 select HAVE_PERF_EVENTS
71 select HAVE_PERF_USER_STACK_DUMP
72 select HAVE_STACKPROTECTOR
73 select HAVE_SYSCALL_TRACEPOINTS
75 select MODULES_USE_ELF_RELA if MODULES
76 select MODULE_SECTIONS if MODULES
78 select OF_EARLY_FLATTREE
80 select PCI_DOMAINS_GENERIC if PCI
84 select SPARSEMEM_STATIC if 32BIT
86 select SYSCTL_EXCEPTION_TRACE
87 select THREAD_INFO_IN_TASK
89 config ARCH_MMAP_RND_BITS_MIN
93 # max bits determined by the following formula:
94 # VA_BITS - PAGE_SHIFT - 3
95 config ARCH_MMAP_RND_BITS_MAX
96 default 24 if 64BIT # SV39 based
99 # set if we run in machine mode, cleared if we run in supervisor mode
104 # set if we are running in S-mode and can use SBI calls
107 depends on !RISCV_M_MODE
111 bool "MMU-based Paged Memory Management Support"
114 Select if you want MMU-based virtualised addressing space
115 support by paged memory management. If unsure, say 'Y'.
133 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
134 default 0x80000000 if 64BIT && !MMU
135 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
136 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
138 config ARCH_FLATMEM_ENABLE
141 config ARCH_SPARSEMEM_ENABLE
144 select SPARSEMEM_VMEMMAP_ENABLE
146 config ARCH_SELECT_MEMORY_MODEL
147 def_bool ARCH_SPARSEMEM_ENABLE
149 config ARCH_WANT_GENERAL_HUGETLB
152 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
155 config SYS_SUPPORTS_HUGETLBFS
159 config STACKTRACE_SUPPORT
162 config TRACE_IRQFLAGS_SUPPORT
168 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
170 config GENERIC_BUG_RELATIVE_POINTERS
173 config GENERIC_CALIBRATE_DELAY
179 config GENERIC_HWEIGHT
182 config FIX_EARLYCON_MEM
185 config PGTABLE_LEVELS
190 config LOCKDEP_SUPPORT
193 source "arch/riscv/Kconfig.socs"
201 This selects the base ISA that this kernel will target and must match
207 select GENERIC_LIB_ASHLDI3
208 select GENERIC_LIB_ASHRDI3
209 select GENERIC_LIB_LSHRDI3
210 select GENERIC_LIB_UCMPDI2
216 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
217 select HAVE_DYNAMIC_FTRACE if MMU
218 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
219 select HAVE_FTRACE_MCOUNT_RECORD
220 select HAVE_FUNCTION_GRAPH_TRACER
221 select HAVE_FUNCTION_TRACER
222 select SWIOTLB if MMU
226 # We must be able to map all physical memory into the kernel, but the compiler
227 # is still a bit more efficient when generating code if it's setup in a manner
228 # such that it can only map 2GiB of memory.
230 prompt "Kernel Code Model"
231 default CMODEL_MEDLOW if 32BIT
232 default CMODEL_MEDANY if 64BIT
235 bool "medium low code model"
237 bool "medium any code model"
240 config MODULE_SECTIONS
242 select HAVE_MOD_ARCH_SPECIFIC
245 prompt "Maximum Physical Memory"
246 default MAXPHYSMEM_2GB if 32BIT
247 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
248 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
250 config MAXPHYSMEM_2GB
252 config MAXPHYSMEM_128GB
253 depends on 64BIT && CMODEL_MEDANY
259 bool "Symmetric Multi-Processing"
261 This enables support for systems with more than one CPU. If
262 you say N here, the kernel will run on single and
263 multiprocessor machines, but will use only one CPU of a
264 multiprocessor machine. If you say Y here, the kernel will run
265 on many, but not all, single processor machines. On a single
266 processor machine, the kernel will run faster if you say N
269 If you don't know what to do here, say N.
272 int "Maximum number of CPUs (2-32)"
278 bool "Support for hot-pluggable CPUs"
280 select GENERIC_IRQ_MIGRATION
283 Say Y here to experiment with turning CPUs off and on. CPUs
284 can be controlled through /sys/devices/system/cpu.
286 Say N if you want to disable CPU hotplug.
298 bool "Emit compressed instructions when building Linux"
301 Adds "C" to the ISA subsets that the toolchain is allowed to emit
302 when building Linux, which results in compressed instructions in the
305 If you don't know what to do here, say Y.
307 menu "supported PMU type"
308 depends on PERF_EVENTS
310 config RISCV_BASE_PMU
311 bool "Base Performance Monitoring Unit"
314 A base PMU that serves as a reference implementation and has limited
315 feature of perf. It can run on any RISC-V machines so serves as the
316 fallback, but this option can also be disable to reduce kernel size.
324 Say N here if you want to disable all floating-point related procedure
327 If you don't know what to do here, say Y.
331 menu "Kernel features"
333 source "kernel/Kconfig.hz"
336 bool "Enable seccomp to safely compute untrusted bytecode"
338 This kernel feature is useful for number crunching applications
339 that may need to compute untrusted bytecode during their
340 execution. By using pipes or other transports made available to
341 the process as file descriptors supporting the read/write
342 syscalls, it's possible to isolate those applications in
343 their own address space using seccomp. Once seccomp is
344 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
345 and the task is only allowed to execute a few safe syscalls
346 defined by each seccomp mode.
349 bool "SBI v0.1 support"
353 This config allows kernel to use SBI v0.1 APIs. This will be
354 deprecated in future once legacy M-mode software are no longer in use.
360 string "Built-in kernel command line"
362 For most platforms, the arguments for the kernel's command line
363 are provided at run-time, during boot. However, there are cases
364 where either no arguments are being provided or the provided
365 arguments are insufficient or even invalid.
367 When that occurs, it is possible to define a built-in command
368 line here and choose how the kernel should use it later on.
371 prompt "Built-in command line usage" if CMDLINE != ""
372 default CMDLINE_FALLBACK
374 Choose how the kernel will handle the provided built-in command
377 config CMDLINE_FALLBACK
378 bool "Use bootloader kernel arguments if available"
380 Use the built-in command line as fallback in case we get nothing
381 during boot. This is the default behaviour.
383 config CMDLINE_EXTEND
384 bool "Extend bootloader kernel arguments"
386 The command-line arguments provided during boot will be
387 appended to the built-in command line. This is useful in
388 cases where the provided arguments are insufficient and
389 you don't want to or cannot modify them.
393 bool "Always use the default kernel command string"
395 Always use the built-in command line, even if we get one during
396 boot. This is useful in case you need to override the provided
397 command line on systems where you don't have or want control
406 depends on RISCV_M_MODE
409 menu "Power management options"
411 source "kernel/power/Kconfig"