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
19 select ARCH_HAS_BINFMT_FLAT
20 select ARCH_HAS_DEBUG_VM_PGTABLE
21 select ARCH_HAS_DEBUG_VIRTUAL if MMU
22 select ARCH_HAS_DEBUG_WX
23 select ARCH_HAS_GCOV_PROFILE_ALL
24 select ARCH_HAS_GIGANTIC_PAGE
26 select ARCH_HAS_MMIOWB
27 select ARCH_HAS_PTE_SPECIAL
28 select ARCH_HAS_SET_DIRECT_MAP
29 select ARCH_HAS_SET_MEMORY
30 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
31 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
32 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
33 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
34 select ARCH_WANT_FRAME_POINTERS
35 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
36 select CLONE_BACKWARDS
37 select CLINT_TIMER if !MMU
40 select GENERIC_ARCH_TOPOLOGY if SMP
41 select GENERIC_ATOMIC64 if !64BIT
42 select GENERIC_EARLY_IOREMAP
43 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
44 select GENERIC_IOREMAP
45 select GENERIC_IRQ_MULTI_HANDLER
46 select GENERIC_IRQ_SHOW
47 select GENERIC_LIB_DEVMEM_IS_ALLOWED
48 select GENERIC_PCI_IOMAP
49 select GENERIC_PTDUMP if MMU
50 select GENERIC_SCHED_CLOCK
51 select GENERIC_SMP_IDLE_THREAD
52 select GENERIC_STRNCPY_FROM_USER if MMU
53 select GENERIC_STRNLEN_USER if MMU
54 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
55 select HANDLE_DOMAIN_IRQ
56 select HAVE_ARCH_AUDITSYSCALL
57 select HAVE_ARCH_JUMP_LABEL
58 select HAVE_ARCH_JUMP_LABEL_RELATIVE
59 select HAVE_ARCH_KASAN if MMU && 64BIT
61 select HAVE_ARCH_KGDB_QXFER_PKT
62 select HAVE_ARCH_MMAP_RND_BITS if MMU
63 select HAVE_ARCH_SECCOMP_FILTER
64 select HAVE_ARCH_TRACEHOOK
65 select HAVE_ASM_MODVERSIONS
66 select HAVE_CONTEXT_TRACKING
67 select HAVE_DEBUG_KMEMLEAK
68 select HAVE_DMA_CONTIGUOUS if MMU
69 select HAVE_EBPF_JIT if MMU
70 select HAVE_FUTEX_CMPXCHG if FUTEX
71 select HAVE_GCC_PLUGINS
72 select HAVE_GENERIC_VDSO if MMU && 64BIT
73 select HAVE_IRQ_TIME_ACCOUNTING
75 select HAVE_KPROBES_ON_FTRACE
76 select HAVE_KRETPROBES
78 select HAVE_PERF_EVENTS
80 select HAVE_PERF_USER_STACK_DUMP
81 select HAVE_REGS_AND_STACK_ACCESS_API
82 select HAVE_STACKPROTECTOR
83 select HAVE_SYSCALL_TRACEPOINTS
85 select MODULES_USE_ELF_RELA if MODULES
86 select MODULE_SECTIONS if MODULES
88 select OF_EARLY_FLATTREE
90 select PCI_DOMAINS_GENERIC if PCI
93 select RISCV_TIMER if RISCV_SBI
94 select SPARSEMEM_STATIC if 32BIT
96 select SYSCTL_EXCEPTION_TRACE
97 select THREAD_INFO_IN_TASK
98 select UACCESS_MEMCPY if !MMU
100 config ARCH_MMAP_RND_BITS_MIN
104 # max bits determined by the following formula:
105 # VA_BITS - PAGE_SHIFT - 3
106 config ARCH_MMAP_RND_BITS_MAX
107 default 24 if 64BIT # SV39 based
110 # set if we run in machine mode, cleared if we run in supervisor mode
115 # set if we are running in S-mode and can use SBI calls
118 depends on !RISCV_M_MODE
122 bool "MMU-based Paged Memory Management Support"
125 Select if you want MMU-based virtualised addressing space
126 support by paged memory management. If unsure, say 'Y'.
144 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
145 default 0x80000000 if 64BIT && !MMU
146 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
147 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
149 config ARCH_FLATMEM_ENABLE
152 config ARCH_SPARSEMEM_ENABLE
155 select SPARSEMEM_VMEMMAP_ENABLE
157 config ARCH_SELECT_MEMORY_MODEL
158 def_bool ARCH_SPARSEMEM_ENABLE
160 config ARCH_WANT_GENERAL_HUGETLB
163 config SYS_SUPPORTS_HUGETLBFS
167 config STACKTRACE_SUPPORT
170 config TRACE_IRQFLAGS_SUPPORT
176 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
178 config GENERIC_BUG_RELATIVE_POINTERS
181 config GENERIC_CALIBRATE_DELAY
187 config GENERIC_HWEIGHT
190 config FIX_EARLYCON_MEM
193 config PGTABLE_LEVELS
198 config LOCKDEP_SUPPORT
201 source "arch/riscv/Kconfig.socs"
209 This selects the base ISA that this kernel will target and must match
215 select GENERIC_LIB_ASHLDI3
216 select GENERIC_LIB_ASHRDI3
217 select GENERIC_LIB_LSHRDI3
218 select GENERIC_LIB_UCMPDI2
224 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
225 select HAVE_DYNAMIC_FTRACE if MMU
226 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
227 select HAVE_FTRACE_MCOUNT_RECORD
228 select HAVE_FUNCTION_GRAPH_TRACER
229 select HAVE_FUNCTION_TRACER
230 select SWIOTLB if MMU
234 # We must be able to map all physical memory into the kernel, but the compiler
235 # is still a bit more efficient when generating code if it's setup in a manner
236 # such that it can only map 2GiB of memory.
238 prompt "Kernel Code Model"
239 default CMODEL_MEDLOW if 32BIT
240 default CMODEL_MEDANY if 64BIT
243 bool "medium low code model"
245 bool "medium any code model"
248 config MODULE_SECTIONS
250 select HAVE_MOD_ARCH_SPECIFIC
253 prompt "Maximum Physical Memory"
254 default MAXPHYSMEM_2GB if 32BIT
255 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
256 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
258 config MAXPHYSMEM_2GB
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.
305 # Common NUMA Features
307 bool "NUMA Memory Allocation and Scheduler Support"
308 select GENERIC_ARCH_NUMA
310 select ARCH_SUPPORTS_NUMA_BALANCING
312 Enable NUMA (Non-Uniform Memory Access) support.
314 The kernel will try to allocate memory used by a CPU on the
315 local memory of the CPU and add some more NUMA awareness to the kernel.
318 int "Maximum NUMA Nodes (as a power of 2)"
321 depends on NEED_MULTIPLE_NODES
323 Specify the maximum number of NUMA Nodes available on the target
324 system. Increases memory reserved to accommodate various tables.
326 config USE_PERCPU_NUMA_NODE_ID
330 config NEED_PER_CPU_EMBED_FIRST_CHUNK
335 bool "Emit compressed instructions when building Linux"
338 Adds "C" to the ISA subsets that the toolchain is allowed to emit
339 when building Linux, which results in compressed instructions in the
342 If you don't know what to do here, say Y.
344 menu "supported PMU type"
345 depends on PERF_EVENTS
347 config RISCV_BASE_PMU
348 bool "Base Performance Monitoring Unit"
351 A base PMU that serves as a reference implementation and has limited
352 feature of perf. It can run on any RISC-V machines so serves as the
353 fallback, but this option can also be disable to reduce kernel size.
361 Say N here if you want to disable all floating-point related procedure
364 If you don't know what to do here, say Y.
368 menu "Kernel features"
370 source "kernel/Kconfig.hz"
373 bool "SBI v0.1 support"
377 This config allows kernel to use SBI v0.1 APIs. This will be
378 deprecated in future once legacy M-mode software are no longer in use.
384 string "Built-in kernel command line"
386 For most platforms, the arguments for the kernel's command line
387 are provided at run-time, during boot. However, there are cases
388 where either no arguments are being provided or the provided
389 arguments are insufficient or even invalid.
391 When that occurs, it is possible to define a built-in command
392 line here and choose how the kernel should use it later on.
395 prompt "Built-in command line usage" if CMDLINE != ""
396 default CMDLINE_FALLBACK
398 Choose how the kernel will handle the provided built-in command
401 config CMDLINE_FALLBACK
402 bool "Use bootloader kernel arguments if available"
404 Use the built-in command line as fallback in case we get nothing
405 during boot. This is the default behaviour.
407 config CMDLINE_EXTEND
408 bool "Extend bootloader kernel arguments"
410 The command-line arguments provided during boot will be
411 appended to the built-in command line. This is useful in
412 cases where the provided arguments are insufficient and
413 you don't want to or cannot modify them.
417 bool "Always use the default kernel command string"
419 Always use the built-in command line, even if we get one during
420 boot. This is useful in case you need to override the provided
421 command line on systems where you don't have or want control
430 bool "UEFI runtime support"
434 select EFI_PARAMS_FROM_FDT
436 select EFI_GENERIC_STUB
437 select EFI_RUNTIME_WRAPPERS
442 This option provides support for runtime services provided
443 by UEFI firmware (such as non-volatile variables, realtime
444 clock, and platform reset). A UEFI stub is also provided to
445 allow the kernel to be booted as an EFI application. This
446 is only useful on systems that have UEFI firmware.
452 depends on RISCV_M_MODE
455 menu "Power management options"
457 source "kernel/power/Kconfig"
461 source "drivers/firmware/Kconfig"