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
71 select HAVE_IRQ_TIME_ACCOUNTING
73 select HAVE_PERF_EVENTS
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_STACKPROTECTOR
77 select HAVE_SYSCALL_TRACEPOINTS
79 select MODULES_USE_ELF_RELA if MODULES
80 select MODULE_SECTIONS if MODULES
82 select OF_EARLY_FLATTREE
84 select PCI_DOMAINS_GENERIC if PCI
87 select RISCV_TIMER if RISCV_SBI
88 select SPARSEMEM_STATIC if 32BIT
90 select SYSCTL_EXCEPTION_TRACE
91 select THREAD_INFO_IN_TASK
92 select UACCESS_MEMCPY if !MMU
94 config ARCH_MMAP_RND_BITS_MIN
98 # max bits determined by the following formula:
99 # VA_BITS - PAGE_SHIFT - 3
100 config ARCH_MMAP_RND_BITS_MAX
101 default 24 if 64BIT # SV39 based
104 # set if we run in machine mode, cleared if we run in supervisor mode
109 # set if we are running in S-mode and can use SBI calls
112 depends on !RISCV_M_MODE
116 bool "MMU-based Paged Memory Management Support"
119 Select if you want MMU-based virtualised addressing space
120 support by paged memory management. If unsure, say 'Y'.
138 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
139 default 0x80000000 if 64BIT && !MMU
140 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
141 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
143 config ARCH_FLATMEM_ENABLE
146 config ARCH_SPARSEMEM_ENABLE
149 select SPARSEMEM_VMEMMAP_ENABLE
151 config ARCH_SELECT_MEMORY_MODEL
152 def_bool ARCH_SPARSEMEM_ENABLE
154 config ARCH_WANT_GENERAL_HUGETLB
157 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
160 config SYS_SUPPORTS_HUGETLBFS
164 config STACKTRACE_SUPPORT
167 config TRACE_IRQFLAGS_SUPPORT
173 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
175 config GENERIC_BUG_RELATIVE_POINTERS
178 config GENERIC_CALIBRATE_DELAY
184 config GENERIC_HWEIGHT
187 config FIX_EARLYCON_MEM
190 config PGTABLE_LEVELS
195 config LOCKDEP_SUPPORT
198 source "arch/riscv/Kconfig.socs"
206 This selects the base ISA that this kernel will target and must match
212 select GENERIC_LIB_ASHLDI3
213 select GENERIC_LIB_ASHRDI3
214 select GENERIC_LIB_LSHRDI3
215 select GENERIC_LIB_UCMPDI2
221 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
222 select HAVE_DYNAMIC_FTRACE if MMU
223 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
224 select HAVE_FTRACE_MCOUNT_RECORD
225 select HAVE_FUNCTION_GRAPH_TRACER
226 select HAVE_FUNCTION_TRACER
227 select SWIOTLB if MMU
231 # We must be able to map all physical memory into the kernel, but the compiler
232 # is still a bit more efficient when generating code if it's setup in a manner
233 # such that it can only map 2GiB of memory.
235 prompt "Kernel Code Model"
236 default CMODEL_MEDLOW if 32BIT
237 default CMODEL_MEDANY if 64BIT
240 bool "medium low code model"
242 bool "medium any code model"
245 config MODULE_SECTIONS
247 select HAVE_MOD_ARCH_SPECIFIC
250 prompt "Maximum Physical Memory"
251 default MAXPHYSMEM_2GB if 32BIT
252 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
253 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
255 config MAXPHYSMEM_2GB
257 config MAXPHYSMEM_128GB
258 depends on 64BIT && CMODEL_MEDANY
264 bool "Symmetric Multi-Processing"
266 This enables support for systems with more than one CPU. If
267 you say N here, the kernel will run on single and
268 multiprocessor machines, but will use only one CPU of a
269 multiprocessor machine. If you say Y here, the kernel will run
270 on many, but not all, single processor machines. On a single
271 processor machine, the kernel will run faster if you say N
274 If you don't know what to do here, say N.
277 int "Maximum number of CPUs (2-32)"
283 bool "Support for hot-pluggable CPUs"
285 select GENERIC_IRQ_MIGRATION
288 Say Y here to experiment with turning CPUs off and on. CPUs
289 can be controlled through /sys/devices/system/cpu.
291 Say N if you want to disable CPU hotplug.
303 bool "Emit compressed instructions when building Linux"
306 Adds "C" to the ISA subsets that the toolchain is allowed to emit
307 when building Linux, which results in compressed instructions in the
310 If you don't know what to do here, say Y.
312 menu "supported PMU type"
313 depends on PERF_EVENTS
315 config RISCV_BASE_PMU
316 bool "Base Performance Monitoring Unit"
319 A base PMU that serves as a reference implementation and has limited
320 feature of perf. It can run on any RISC-V machines so serves as the
321 fallback, but this option can also be disable to reduce kernel size.
329 Say N here if you want to disable all floating-point related procedure
332 If you don't know what to do here, say Y.
336 menu "Kernel features"
338 source "kernel/Kconfig.hz"
341 bool "SBI v0.1 support"
345 This config allows kernel to use SBI v0.1 APIs. This will be
346 deprecated in future once legacy M-mode software are no longer in use.
352 string "Built-in kernel command line"
354 For most platforms, the arguments for the kernel's command line
355 are provided at run-time, during boot. However, there are cases
356 where either no arguments are being provided or the provided
357 arguments are insufficient or even invalid.
359 When that occurs, it is possible to define a built-in command
360 line here and choose how the kernel should use it later on.
363 prompt "Built-in command line usage" if CMDLINE != ""
364 default CMDLINE_FALLBACK
366 Choose how the kernel will handle the provided built-in command
369 config CMDLINE_FALLBACK
370 bool "Use bootloader kernel arguments if available"
372 Use the built-in command line as fallback in case we get nothing
373 during boot. This is the default behaviour.
375 config CMDLINE_EXTEND
376 bool "Extend bootloader kernel arguments"
378 The command-line arguments provided during boot will be
379 appended to the built-in command line. This is useful in
380 cases where the provided arguments are insufficient and
381 you don't want to or cannot modify them.
385 bool "Always use the default kernel command string"
387 Always use the built-in command line, even if we get one during
388 boot. This is useful in case you need to override the provided
389 command line on systems where you don't have or want control
398 bool "UEFI runtime support"
402 select EFI_PARAMS_FROM_FDT
404 select EFI_GENERIC_STUB
405 select EFI_RUNTIME_WRAPPERS
410 This option provides support for runtime services provided
411 by UEFI firmware (such as non-volatile variables, realtime
412 clock, and platform reset). A UEFI stub is also provided to
413 allow the kernel to be booted as an EFI application. This
414 is only useful on systems that have UEFI firmware.
420 depends on RISCV_M_MODE
423 menu "Power management options"
425 source "kernel/power/Kconfig"
429 source "drivers/firmware/Kconfig"