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
88 select SYSCTL_EXCEPTION_TRACE
89 select THREAD_INFO_IN_TASK
90 select UACCESS_MEMCPY if !MMU
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_1GB
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_STATIC if 32BIT && SPARSEMEM
148 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
150 config ARCH_SELECT_MEMORY_MODEL
151 def_bool ARCH_SPARSEMEM_ENABLE
153 config ARCH_WANT_GENERAL_HUGETLB
156 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
159 config SYS_SUPPORTS_HUGETLBFS
163 config STACKTRACE_SUPPORT
166 config TRACE_IRQFLAGS_SUPPORT
172 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
174 config GENERIC_BUG_RELATIVE_POINTERS
177 config GENERIC_CALIBRATE_DELAY
183 config GENERIC_HWEIGHT
186 config FIX_EARLYCON_MEM
189 config PGTABLE_LEVELS
194 config LOCKDEP_SUPPORT
197 source "arch/riscv/Kconfig.socs"
205 This selects the base ISA that this kernel will target and must match
211 select GENERIC_LIB_ASHLDI3
212 select GENERIC_LIB_ASHRDI3
213 select GENERIC_LIB_LSHRDI3
214 select GENERIC_LIB_UCMPDI2
220 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
221 select HAVE_DYNAMIC_FTRACE if MMU
222 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
223 select HAVE_FTRACE_MCOUNT_RECORD
224 select HAVE_FUNCTION_GRAPH_TRACER
225 select HAVE_FUNCTION_TRACER
226 select SWIOTLB if MMU
230 # We must be able to map all physical memory into the kernel, but the compiler
231 # is still a bit more efficient when generating code if it's setup in a manner
232 # such that it can only map 2GiB of memory.
234 prompt "Kernel Code Model"
235 default CMODEL_MEDLOW if 32BIT
236 default CMODEL_MEDANY if 64BIT
239 bool "medium low code model"
241 bool "medium any code model"
244 config MODULE_SECTIONS
246 select HAVE_MOD_ARCH_SPECIFIC
249 prompt "Maximum Physical Memory"
250 default MAXPHYSMEM_1GB if 32BIT
251 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
252 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
254 config MAXPHYSMEM_1GB
257 config MAXPHYSMEM_2GB
258 depends on 64BIT && CMODEL_MEDLOW
260 config MAXPHYSMEM_128GB
261 depends on 64BIT && CMODEL_MEDANY
267 bool "Symmetric Multi-Processing"
269 This enables support for systems with more than one CPU. If
270 you say N here, the kernel will run on single and
271 multiprocessor machines, but will use only one CPU of a
272 multiprocessor machine. If you say Y here, the kernel will run
273 on many, but not all, single processor machines. On a single
274 processor machine, the kernel will run faster if you say N
277 If you don't know what to do here, say N.
280 int "Maximum number of CPUs (2-32)"
286 bool "Support for hot-pluggable CPUs"
288 select GENERIC_IRQ_MIGRATION
291 Say Y here to experiment with turning CPUs off and on. CPUs
292 can be controlled through /sys/devices/system/cpu.
294 Say N if you want to disable CPU hotplug.
306 bool "Emit compressed instructions when building Linux"
309 Adds "C" to the ISA subsets that the toolchain is allowed to emit
310 when building Linux, which results in compressed instructions in the
313 If you don't know what to do here, say Y.
315 menu "supported PMU type"
316 depends on PERF_EVENTS
318 config RISCV_BASE_PMU
319 bool "Base Performance Monitoring Unit"
322 A base PMU that serves as a reference implementation and has limited
323 feature of perf. It can run on any RISC-V machines so serves as the
324 fallback, but this option can also be disable to reduce kernel size.
332 Say N here if you want to disable all floating-point related procedure
335 If you don't know what to do here, say Y.
339 menu "Kernel features"
341 source "kernel/Kconfig.hz"
344 bool "SBI v0.1 support"
348 This config allows kernel to use SBI v0.1 APIs. This will be
349 deprecated in future once legacy M-mode software are no longer in use.
355 string "Built-in kernel command line"
357 For most platforms, the arguments for the kernel's command line
358 are provided at run-time, during boot. However, there are cases
359 where either no arguments are being provided or the provided
360 arguments are insufficient or even invalid.
362 When that occurs, it is possible to define a built-in command
363 line here and choose how the kernel should use it later on.
366 prompt "Built-in command line usage" if CMDLINE != ""
367 default CMDLINE_FALLBACK
369 Choose how the kernel will handle the provided built-in command
372 config CMDLINE_FALLBACK
373 bool "Use bootloader kernel arguments if available"
375 Use the built-in command line as fallback in case we get nothing
376 during boot. This is the default behaviour.
378 config CMDLINE_EXTEND
379 bool "Extend bootloader kernel arguments"
381 The command-line arguments provided during boot will be
382 appended to the built-in command line. This is useful in
383 cases where the provided arguments are insufficient and
384 you don't want to or cannot modify them.
388 bool "Always use the default kernel command string"
390 Always use the built-in command line, even if we get one during
391 boot. This is useful in case you need to override the provided
392 command line on systems where you don't have or want control
401 bool "UEFI runtime support"
405 select EFI_PARAMS_FROM_FDT
407 select EFI_GENERIC_STUB
408 select EFI_RUNTIME_WRAPPERS
413 This option provides support for runtime services provided
414 by UEFI firmware (such as non-volatile variables, realtime
415 clock, and platform reset). A UEFI stub is also provided to
416 allow the kernel to be booted as an EFI application. This
417 is only useful on systems that have UEFI firmware.
423 depends on RISCV_M_MODE
426 menu "Power management options"
428 source "kernel/power/Kconfig"
432 source "drivers/firmware/Kconfig"