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
35 select CLINT_TIMER if !MMU
38 select GENERIC_ARCH_TOPOLOGY if SMP
39 select GENERIC_ATOMIC64 if !64BIT
40 select GENERIC_CLOCKEVENTS
41 select GENERIC_EARLY_IOREMAP
42 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
43 select GENERIC_IOREMAP
44 select GENERIC_IRQ_MULTI_HANDLER
45 select GENERIC_IRQ_SHOW
46 select GENERIC_PCI_IOMAP
47 select GENERIC_PTDUMP if MMU
48 select GENERIC_SCHED_CLOCK
49 select GENERIC_SMP_IDLE_THREAD
50 select GENERIC_STRNCPY_FROM_USER if MMU
51 select GENERIC_STRNLEN_USER if MMU
52 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
53 select HANDLE_DOMAIN_IRQ
54 select HAVE_ARCH_AUDITSYSCALL
55 select HAVE_ARCH_JUMP_LABEL
56 select HAVE_ARCH_JUMP_LABEL_RELATIVE
57 select HAVE_ARCH_KASAN if MMU && 64BIT
59 select HAVE_ARCH_KGDB_QXFER_PKT
60 select HAVE_ARCH_MMAP_RND_BITS if MMU
61 select HAVE_ARCH_SECCOMP_FILTER
62 select HAVE_ARCH_TRACEHOOK
63 select HAVE_ASM_MODVERSIONS
64 select HAVE_CONTEXT_TRACKING
65 select HAVE_DEBUG_KMEMLEAK
66 select HAVE_DMA_CONTIGUOUS if MMU
67 select HAVE_EBPF_JIT if MMU
68 select HAVE_FUTEX_CMPXCHG if FUTEX
69 select HAVE_GCC_PLUGINS
70 select HAVE_GENERIC_VDSO if MMU && 64BIT
72 select HAVE_PERF_EVENTS
74 select HAVE_PERF_USER_STACK_DUMP
75 select HAVE_STACKPROTECTOR
76 select HAVE_SYSCALL_TRACEPOINTS
78 select MODULES_USE_ELF_RELA if MODULES
79 select MODULE_SECTIONS if MODULES
81 select OF_EARLY_FLATTREE
83 select PCI_DOMAINS_GENERIC if PCI
86 select RISCV_TIMER if RISCV_SBI
87 select SPARSEMEM_STATIC if 32BIT
89 select SYSCTL_EXCEPTION_TRACE
90 select THREAD_INFO_IN_TASK
92 config ARCH_MMAP_RND_BITS_MIN
96 # max bits determined by the following formula:
97 # VA_BITS - PAGE_SHIFT - 3
98 config ARCH_MMAP_RND_BITS_MAX
99 default 24 if 64BIT # SV39 based
102 # set if we run in machine mode, cleared if we run in supervisor mode
107 # set if we are running in S-mode and can use SBI calls
110 depends on !RISCV_M_MODE
114 bool "MMU-based Paged Memory Management Support"
117 Select if you want MMU-based virtualised addressing space
118 support by paged memory management. If unsure, say 'Y'.
136 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
137 default 0x80000000 if 64BIT && !MMU
138 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
139 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
141 config ARCH_FLATMEM_ENABLE
144 config ARCH_SPARSEMEM_ENABLE
147 select SPARSEMEM_VMEMMAP_ENABLE
149 config ARCH_SELECT_MEMORY_MODEL
150 def_bool ARCH_SPARSEMEM_ENABLE
152 config ARCH_WANT_GENERAL_HUGETLB
155 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
158 config SYS_SUPPORTS_HUGETLBFS
162 config STACKTRACE_SUPPORT
165 config TRACE_IRQFLAGS_SUPPORT
171 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
173 config GENERIC_BUG_RELATIVE_POINTERS
176 config GENERIC_CALIBRATE_DELAY
182 config GENERIC_HWEIGHT
185 config FIX_EARLYCON_MEM
188 config PGTABLE_LEVELS
193 config LOCKDEP_SUPPORT
196 source "arch/riscv/Kconfig.socs"
204 This selects the base ISA that this kernel will target and must match
210 select GENERIC_LIB_ASHLDI3
211 select GENERIC_LIB_ASHRDI3
212 select GENERIC_LIB_LSHRDI3
213 select GENERIC_LIB_UCMPDI2
219 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
220 select HAVE_DYNAMIC_FTRACE if MMU
221 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
222 select HAVE_FTRACE_MCOUNT_RECORD
223 select HAVE_FUNCTION_GRAPH_TRACER
224 select HAVE_FUNCTION_TRACER
225 select SWIOTLB if MMU
229 # We must be able to map all physical memory into the kernel, but the compiler
230 # is still a bit more efficient when generating code if it's setup in a manner
231 # such that it can only map 2GiB of memory.
233 prompt "Kernel Code Model"
234 default CMODEL_MEDLOW if 32BIT
235 default CMODEL_MEDANY if 64BIT
238 bool "medium low code model"
240 bool "medium any code model"
243 config MODULE_SECTIONS
245 select HAVE_MOD_ARCH_SPECIFIC
248 prompt "Maximum Physical Memory"
249 default MAXPHYSMEM_2GB if 32BIT
250 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
251 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
253 config MAXPHYSMEM_2GB
255 config MAXPHYSMEM_128GB
256 depends on 64BIT && CMODEL_MEDANY
262 bool "Symmetric Multi-Processing"
264 This enables support for systems with more than one CPU. If
265 you say N here, the kernel will run on single and
266 multiprocessor machines, but will use only one CPU of a
267 multiprocessor machine. If you say Y here, the kernel will run
268 on many, but not all, single processor machines. On a single
269 processor machine, the kernel will run faster if you say N
272 If you don't know what to do here, say N.
275 int "Maximum number of CPUs (2-32)"
281 bool "Support for hot-pluggable CPUs"
283 select GENERIC_IRQ_MIGRATION
286 Say Y here to experiment with turning CPUs off and on. CPUs
287 can be controlled through /sys/devices/system/cpu.
289 Say N if you want to disable CPU hotplug.
301 bool "Emit compressed instructions when building Linux"
304 Adds "C" to the ISA subsets that the toolchain is allowed to emit
305 when building Linux, which results in compressed instructions in the
308 If you don't know what to do here, say Y.
310 menu "supported PMU type"
311 depends on PERF_EVENTS
313 config RISCV_BASE_PMU
314 bool "Base Performance Monitoring Unit"
317 A base PMU that serves as a reference implementation and has limited
318 feature of perf. It can run on any RISC-V machines so serves as the
319 fallback, but this option can also be disable to reduce kernel size.
327 Say N here if you want to disable all floating-point related procedure
330 If you don't know what to do here, say Y.
334 menu "Kernel features"
336 source "kernel/Kconfig.hz"
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 bool "UEFI runtime support"
400 select EFI_PARAMS_FROM_FDT
402 select EFI_GENERIC_STUB
403 select EFI_RUNTIME_WRAPPERS
408 This option provides support for runtime services provided
409 by UEFI firmware (such as non-volatile variables, realtime
410 clock, and platform reset). A UEFI stub is also provided to
411 allow the kernel to be booted as an EFI application. This
412 is only useful on systems that have UEFI firmware.
418 depends on RISCV_M_MODE
421 menu "Power management options"
423 source "kernel/power/Kconfig"
427 source "drivers/firmware/Kconfig"