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_SUPPORTS_DEBUG_PAGEALLOC if MMU
18 select ARCH_HAS_BINFMT_FLAT
19 select ARCH_HAS_DEBUG_VM_PGTABLE
20 select ARCH_HAS_DEBUG_VIRTUAL if MMU
21 select ARCH_HAS_DEBUG_WX
22 select ARCH_HAS_GCOV_PROFILE_ALL
23 select ARCH_HAS_GIGANTIC_PAGE
25 select ARCH_HAS_MMIOWB
26 select ARCH_HAS_PTE_SPECIAL
27 select ARCH_HAS_SET_DIRECT_MAP
28 select ARCH_HAS_SET_MEMORY
29 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
30 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
31 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
32 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
33 select ARCH_WANT_FRAME_POINTERS
34 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
35 select CLONE_BACKWARDS
36 select CLINT_TIMER if !MMU
39 select GENERIC_ARCH_TOPOLOGY if SMP
40 select GENERIC_ATOMIC64 if !64BIT
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
91 select UACCESS_MEMCPY if !MMU
93 config ARCH_MMAP_RND_BITS_MIN
97 # max bits determined by the following formula:
98 # VA_BITS - PAGE_SHIFT - 3
99 config ARCH_MMAP_RND_BITS_MAX
100 default 24 if 64BIT # SV39 based
103 # set if we run in machine mode, cleared if we run in supervisor mode
108 # set if we are running in S-mode and can use SBI calls
111 depends on !RISCV_M_MODE
115 bool "MMU-based Paged Memory Management Support"
118 Select if you want MMU-based virtualised addressing space
119 support by paged memory management. If unsure, say 'Y'.
137 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
138 default 0x80000000 if 64BIT && !MMU
139 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
140 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
142 config ARCH_FLATMEM_ENABLE
145 config ARCH_SPARSEMEM_ENABLE
148 select SPARSEMEM_VMEMMAP_ENABLE
150 config ARCH_SELECT_MEMORY_MODEL
151 def_bool ARCH_SPARSEMEM_ENABLE
153 config ARCH_WANT_GENERAL_HUGETLB
156 config SYS_SUPPORTS_HUGETLBFS
160 config STACKTRACE_SUPPORT
163 config TRACE_IRQFLAGS_SUPPORT
169 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
171 config GENERIC_BUG_RELATIVE_POINTERS
174 config GENERIC_CALIBRATE_DELAY
180 config GENERIC_HWEIGHT
183 config FIX_EARLYCON_MEM
186 config PGTABLE_LEVELS
191 config LOCKDEP_SUPPORT
194 source "arch/riscv/Kconfig.socs"
202 This selects the base ISA that this kernel will target and must match
208 select GENERIC_LIB_ASHLDI3
209 select GENERIC_LIB_ASHRDI3
210 select GENERIC_LIB_LSHRDI3
211 select GENERIC_LIB_UCMPDI2
217 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
218 select HAVE_DYNAMIC_FTRACE if MMU
219 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
220 select HAVE_FTRACE_MCOUNT_RECORD
221 select HAVE_FUNCTION_GRAPH_TRACER
222 select HAVE_FUNCTION_TRACER
223 select SWIOTLB if MMU
227 # We must be able to map all physical memory into the kernel, but the compiler
228 # is still a bit more efficient when generating code if it's setup in a manner
229 # such that it can only map 2GiB of memory.
231 prompt "Kernel Code Model"
232 default CMODEL_MEDLOW if 32BIT
233 default CMODEL_MEDANY if 64BIT
236 bool "medium low code model"
238 bool "medium any code model"
241 config MODULE_SECTIONS
243 select HAVE_MOD_ARCH_SPECIFIC
246 prompt "Maximum Physical Memory"
247 default MAXPHYSMEM_2GB if 32BIT
248 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
249 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
251 config MAXPHYSMEM_2GB
253 config MAXPHYSMEM_128GB
254 depends on 64BIT && CMODEL_MEDANY
260 bool "Symmetric Multi-Processing"
262 This enables support for systems with more than one CPU. If
263 you say N here, the kernel will run on single and
264 multiprocessor machines, but will use only one CPU of a
265 multiprocessor machine. If you say Y here, the kernel will run
266 on many, but not all, single processor machines. On a single
267 processor machine, the kernel will run faster if you say N
270 If you don't know what to do here, say N.
273 int "Maximum number of CPUs (2-32)"
279 bool "Support for hot-pluggable CPUs"
281 select GENERIC_IRQ_MIGRATION
284 Say Y here to experiment with turning CPUs off and on. CPUs
285 can be controlled through /sys/devices/system/cpu.
287 Say N if you want to disable CPU hotplug.
299 bool "Emit compressed instructions when building Linux"
302 Adds "C" to the ISA subsets that the toolchain is allowed to emit
303 when building Linux, which results in compressed instructions in the
306 If you don't know what to do here, say Y.
308 menu "supported PMU type"
309 depends on PERF_EVENTS
311 config RISCV_BASE_PMU
312 bool "Base Performance Monitoring Unit"
315 A base PMU that serves as a reference implementation and has limited
316 feature of perf. It can run on any RISC-V machines so serves as the
317 fallback, but this option can also be disable to reduce kernel size.
325 Say N here if you want to disable all floating-point related procedure
328 If you don't know what to do here, say Y.
332 menu "Kernel features"
334 source "kernel/Kconfig.hz"
337 bool "SBI v0.1 support"
341 This config allows kernel to use SBI v0.1 APIs. This will be
342 deprecated in future once legacy M-mode software are no longer in use.
348 string "Built-in kernel command line"
350 For most platforms, the arguments for the kernel's command line
351 are provided at run-time, during boot. However, there are cases
352 where either no arguments are being provided or the provided
353 arguments are insufficient or even invalid.
355 When that occurs, it is possible to define a built-in command
356 line here and choose how the kernel should use it later on.
359 prompt "Built-in command line usage" if CMDLINE != ""
360 default CMDLINE_FALLBACK
362 Choose how the kernel will handle the provided built-in command
365 config CMDLINE_FALLBACK
366 bool "Use bootloader kernel arguments if available"
368 Use the built-in command line as fallback in case we get nothing
369 during boot. This is the default behaviour.
371 config CMDLINE_EXTEND
372 bool "Extend bootloader kernel arguments"
374 The command-line arguments provided during boot will be
375 appended to the built-in command line. This is useful in
376 cases where the provided arguments are insufficient and
377 you don't want to or cannot modify them.
381 bool "Always use the default kernel command string"
383 Always use the built-in command line, even if we get one during
384 boot. This is useful in case you need to override the provided
385 command line on systems where you don't have or want control
394 bool "UEFI runtime support"
398 select EFI_PARAMS_FROM_FDT
400 select EFI_GENERIC_STUB
401 select EFI_RUNTIME_WRAPPERS
406 This option provides support for runtime services provided
407 by UEFI firmware (such as non-volatile variables, realtime
408 clock, and platform reset). A UEFI stub is also provided to
409 allow the kernel to be booted as an EFI application. This
410 is only useful on systems that have UEFI firmware.
416 depends on RISCV_M_MODE
419 menu "Power management options"
421 source "kernel/power/Kconfig"
425 source "drivers/firmware/Kconfig"