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_HAS_BINFMT_FLAT
17 select ARCH_HAS_DEBUG_VIRTUAL if MMU
18 select ARCH_HAS_DEBUG_WX
19 select ARCH_HAS_GCOV_PROFILE_ALL
20 select ARCH_HAS_GIGANTIC_PAGE
21 select ARCH_HAS_MMIOWB
22 select ARCH_HAS_PTE_SPECIAL
23 select ARCH_HAS_SET_DIRECT_MAP
24 select ARCH_HAS_SET_MEMORY
25 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
26 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
27 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
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_KASAN if MMU && 64BIT
52 select HAVE_ARCH_KGDB_QXFER_PKT
53 select HAVE_ARCH_MMAP_RND_BITS if MMU
54 select HAVE_ARCH_SECCOMP_FILTER
55 select HAVE_ARCH_TRACEHOOK
56 select HAVE_ASM_MODVERSIONS
57 select HAVE_COPY_THREAD_TLS
58 select HAVE_DMA_CONTIGUOUS if MMU
59 select HAVE_EBPF_JIT if MMU
60 select HAVE_FUTEX_CMPXCHG if FUTEX
61 select HAVE_GENERIC_VDSO if MMU && 64BIT
63 select HAVE_PERF_EVENTS
65 select HAVE_PERF_USER_STACK_DUMP
66 select HAVE_SYSCALL_TRACEPOINTS
68 select MODULES_USE_ELF_RELA if MODULES
69 select MODULE_SECTIONS if MODULES
71 select OF_EARLY_FLATTREE
73 select PCI_DOMAINS_GENERIC if PCI
77 select SPARSEMEM_STATIC if 32BIT
79 select SYSCTL_EXCEPTION_TRACE
80 select THREAD_INFO_IN_TASK
82 config ARCH_MMAP_RND_BITS_MIN
86 # max bits determined by the following formula:
87 # VA_BITS - PAGE_SHIFT - 3
88 config ARCH_MMAP_RND_BITS_MAX
89 default 24 if 64BIT # SV39 based
92 # set if we run in machine mode, cleared if we run in supervisor mode
97 # set if we are running in S-mode and can use SBI calls
100 depends on !RISCV_M_MODE
104 bool "MMU-based Paged Memory Management Support"
107 Select if you want MMU-based virtualised addressing space
108 support by paged memory management. If unsure, say 'Y'.
126 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
127 default 0x80000000 if 64BIT && !MMU
128 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
129 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
131 config ARCH_FLATMEM_ENABLE
134 config ARCH_SPARSEMEM_ENABLE
137 select SPARSEMEM_VMEMMAP_ENABLE
139 config ARCH_SELECT_MEMORY_MODEL
140 def_bool ARCH_SPARSEMEM_ENABLE
142 config ARCH_WANT_GENERAL_HUGETLB
145 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
148 config SYS_SUPPORTS_HUGETLBFS
152 config STACKTRACE_SUPPORT
155 config TRACE_IRQFLAGS_SUPPORT
161 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
163 config GENERIC_BUG_RELATIVE_POINTERS
166 config GENERIC_CALIBRATE_DELAY
172 config GENERIC_HWEIGHT
175 config FIX_EARLYCON_MEM
178 config PGTABLE_LEVELS
183 source "arch/riscv/Kconfig.socs"
191 This selects the base ISA that this kernel will target and must match
197 select GENERIC_LIB_ASHLDI3
198 select GENERIC_LIB_ASHRDI3
199 select GENERIC_LIB_LSHRDI3
200 select GENERIC_LIB_UCMPDI2
206 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
207 select HAVE_DYNAMIC_FTRACE if MMU
208 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
209 select HAVE_FTRACE_MCOUNT_RECORD
210 select HAVE_FUNCTION_GRAPH_TRACER
211 select HAVE_FUNCTION_TRACER
212 select SWIOTLB if MMU
216 # We must be able to map all physical memory into the kernel, but the compiler
217 # is still a bit more efficient when generating code if it's setup in a manner
218 # such that it can only map 2GiB of memory.
220 prompt "Kernel Code Model"
221 default CMODEL_MEDLOW if 32BIT
222 default CMODEL_MEDANY if 64BIT
225 bool "medium low code model"
227 bool "medium any code model"
230 config MODULE_SECTIONS
232 select HAVE_MOD_ARCH_SPECIFIC
235 prompt "Maximum Physical Memory"
236 default MAXPHYSMEM_2GB if 32BIT
237 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
238 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
240 config MAXPHYSMEM_2GB
242 config MAXPHYSMEM_128GB
243 depends on 64BIT && CMODEL_MEDANY
249 bool "Symmetric Multi-Processing"
251 This enables support for systems with more than one CPU. If
252 you say N here, the kernel will run on single and
253 multiprocessor machines, but will use only one CPU of a
254 multiprocessor machine. If you say Y here, the kernel will run
255 on many, but not all, single processor machines. On a single
256 processor machine, the kernel will run faster if you say N
259 If you don't know what to do here, say N.
262 int "Maximum number of CPUs (2-32)"
268 bool "Support for hot-pluggable CPUs"
270 select GENERIC_IRQ_MIGRATION
273 Say Y here to experiment with turning CPUs off and on. CPUs
274 can be controlled through /sys/devices/system/cpu.
276 Say N if you want to disable CPU hotplug.
288 bool "Emit compressed instructions when building Linux"
291 Adds "C" to the ISA subsets that the toolchain is allowed to emit
292 when building Linux, which results in compressed instructions in the
295 If you don't know what to do here, say Y.
297 menu "supported PMU type"
298 depends on PERF_EVENTS
300 config RISCV_BASE_PMU
301 bool "Base Performance Monitoring Unit"
304 A base PMU that serves as a reference implementation and has limited
305 feature of perf. It can run on any RISC-V machines so serves as the
306 fallback, but this option can also be disable to reduce kernel size.
314 Say N here if you want to disable all floating-point related procedure
317 If you don't know what to do here, say Y.
321 menu "Kernel features"
323 source "kernel/Kconfig.hz"
326 bool "Enable seccomp to safely compute untrusted bytecode"
328 This kernel feature is useful for number crunching applications
329 that may need to compute untrusted bytecode during their
330 execution. By using pipes or other transports made available to
331 the process as file descriptors supporting the read/write
332 syscalls, it's possible to isolate those applications in
333 their own address space using seccomp. Once seccomp is
334 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
335 and the task is only allowed to execute a few safe syscalls
336 defined by each seccomp mode.
339 bool "SBI v0.1 support"
343 This config allows kernel to use SBI v0.1 APIs. This will be
344 deprecated in future once legacy M-mode software are no longer in use.
350 string "Built-in kernel command line"
352 For most platforms, the arguments for the kernel's command line
353 are provided at run-time, during boot. However, there are cases
354 where either no arguments are being provided or the provided
355 arguments are insufficient or even invalid.
357 When that occurs, it is possible to define a built-in command
358 line here and choose how the kernel should use it later on.
361 prompt "Built-in command line usage" if CMDLINE != ""
362 default CMDLINE_FALLBACK
364 Choose how the kernel will handle the provided built-in command
367 config CMDLINE_FALLBACK
368 bool "Use bootloader kernel arguments if available"
370 Use the built-in command line as fallback in case we get nothing
371 during boot. This is the default behaviour.
373 config CMDLINE_EXTEND
374 bool "Extend bootloader kernel arguments"
376 The command-line arguments provided during boot will be
377 appended to the built-in command line. This is useful in
378 cases where the provided arguments are insufficient and
379 you don't want to or cannot modify them.
383 bool "Always use the default kernel command string"
385 Always use the built-in command line, even if we get one during
386 boot. This is useful in case you need to override the provided
387 command line on systems where you don't have or want control
396 depends on RISCV_M_MODE
399 menu "Power management options"
401 source "kernel/power/Kconfig"