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
60 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
62 select HAVE_ARCH_KGDB_QXFER_PKT
63 select HAVE_ARCH_MMAP_RND_BITS if MMU
64 select HAVE_ARCH_SECCOMP_FILTER
65 select HAVE_ARCH_TRACEHOOK
66 select HAVE_ASM_MODVERSIONS
67 select HAVE_CONTEXT_TRACKING
68 select HAVE_DEBUG_KMEMLEAK
69 select HAVE_DMA_CONTIGUOUS if MMU
70 select HAVE_EBPF_JIT if MMU
71 select HAVE_FUNCTION_ERROR_INJECTION
72 select HAVE_FUTEX_CMPXCHG if FUTEX
73 select HAVE_GCC_PLUGINS
74 select HAVE_GENERIC_VDSO if MMU && 64BIT
75 select HAVE_IRQ_TIME_ACCOUNTING
77 select HAVE_KPROBES_ON_FTRACE
78 select HAVE_KRETPROBES
80 select HAVE_PERF_EVENTS
82 select HAVE_PERF_USER_STACK_DUMP
83 select HAVE_REGS_AND_STACK_ACCESS_API
84 select HAVE_STACKPROTECTOR
85 select HAVE_SYSCALL_TRACEPOINTS
87 select MODULES_USE_ELF_RELA if MODULES
88 select MODULE_SECTIONS if MODULES
90 select OF_EARLY_FLATTREE
92 select PCI_DOMAINS_GENERIC if PCI
95 select RISCV_TIMER if RISCV_SBI
97 select SYSCTL_EXCEPTION_TRACE
98 select THREAD_INFO_IN_TASK
99 select UACCESS_MEMCPY if !MMU
101 config ARCH_MMAP_RND_BITS_MIN
105 # max bits determined by the following formula:
106 # VA_BITS - PAGE_SHIFT - 3
107 config ARCH_MMAP_RND_BITS_MAX
108 default 24 if 64BIT # SV39 based
111 # set if we run in machine mode, cleared if we run in supervisor mode
116 # set if we are running in S-mode and can use SBI calls
119 depends on !RISCV_M_MODE
123 bool "MMU-based Paged Memory Management Support"
126 Select if you want MMU-based virtualised addressing space
127 support by paged memory management. If unsure, say 'Y'.
145 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
146 default 0x80000000 if 64BIT && !MMU
147 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
148 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
150 config ARCH_FLATMEM_ENABLE
153 config ARCH_SPARSEMEM_ENABLE
156 select SPARSEMEM_STATIC if 32BIT && SPARSMEM
157 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
159 config ARCH_SELECT_MEMORY_MODEL
160 def_bool ARCH_SPARSEMEM_ENABLE
162 config ARCH_WANT_GENERAL_HUGETLB
165 config ARCH_SUPPORTS_UPROBES
168 config SYS_SUPPORTS_HUGETLBFS
172 config STACKTRACE_SUPPORT
175 config TRACE_IRQFLAGS_SUPPORT
181 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
183 config GENERIC_BUG_RELATIVE_POINTERS
186 config GENERIC_CALIBRATE_DELAY
192 config GENERIC_HWEIGHT
195 config FIX_EARLYCON_MEM
198 config PGTABLE_LEVELS
203 config LOCKDEP_SUPPORT
206 source "arch/riscv/Kconfig.socs"
214 This selects the base ISA that this kernel will target and must match
220 select GENERIC_LIB_ASHLDI3
221 select GENERIC_LIB_ASHRDI3
222 select GENERIC_LIB_LSHRDI3
223 select GENERIC_LIB_UCMPDI2
229 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
230 select HAVE_DYNAMIC_FTRACE if MMU
231 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
232 select HAVE_FTRACE_MCOUNT_RECORD
233 select HAVE_FUNCTION_GRAPH_TRACER
234 select HAVE_FUNCTION_TRACER
235 select SWIOTLB if MMU
239 # We must be able to map all physical memory into the kernel, but the compiler
240 # is still a bit more efficient when generating code if it's setup in a manner
241 # such that it can only map 2GiB of memory.
243 prompt "Kernel Code Model"
244 default CMODEL_MEDLOW if 32BIT
245 default CMODEL_MEDANY if 64BIT
248 bool "medium low code model"
250 bool "medium any code model"
253 config MODULE_SECTIONS
255 select HAVE_MOD_ARCH_SPECIFIC
258 prompt "Maximum Physical Memory"
259 default MAXPHYSMEM_1GB if 32BIT
260 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
261 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
263 config MAXPHYSMEM_1GB
266 config MAXPHYSMEM_2GB
267 depends on 64BIT && CMODEL_MEDLOW
269 config MAXPHYSMEM_128GB
270 depends on 64BIT && CMODEL_MEDANY
276 bool "Symmetric Multi-Processing"
278 This enables support for systems with more than one CPU. If
279 you say N here, the kernel will run on single and
280 multiprocessor machines, but will use only one CPU of a
281 multiprocessor machine. If you say Y here, the kernel will run
282 on many, but not all, single processor machines. On a single
283 processor machine, the kernel will run faster if you say N
286 If you don't know what to do here, say N.
289 int "Maximum number of CPUs (2-32)"
295 bool "Support for hot-pluggable CPUs"
297 select GENERIC_IRQ_MIGRATION
300 Say Y here to experiment with turning CPUs off and on. CPUs
301 can be controlled through /sys/devices/system/cpu.
303 Say N if you want to disable CPU hotplug.
314 # Common NUMA Features
316 bool "NUMA Memory Allocation and Scheduler Support"
318 select GENERIC_ARCH_NUMA
320 select ARCH_SUPPORTS_NUMA_BALANCING
322 Enable NUMA (Non-Uniform Memory Access) support.
324 The kernel will try to allocate memory used by a CPU on the
325 local memory of the CPU and add some more NUMA awareness to the kernel.
328 int "Maximum NUMA Nodes (as a power of 2)"
331 depends on NEED_MULTIPLE_NODES
333 Specify the maximum number of NUMA Nodes available on the target
334 system. Increases memory reserved to accommodate various tables.
336 config USE_PERCPU_NUMA_NODE_ID
340 config NEED_PER_CPU_EMBED_FIRST_CHUNK
345 bool "Emit compressed instructions when building Linux"
348 Adds "C" to the ISA subsets that the toolchain is allowed to emit
349 when building Linux, which results in compressed instructions in the
352 If you don't know what to do here, say Y.
354 menu "supported PMU type"
355 depends on PERF_EVENTS
357 config RISCV_BASE_PMU
358 bool "Base Performance Monitoring Unit"
361 A base PMU that serves as a reference implementation and has limited
362 feature of perf. It can run on any RISC-V machines so serves as the
363 fallback, but this option can also be disable to reduce kernel size.
371 Say N here if you want to disable all floating-point related procedure
374 If you don't know what to do here, say Y.
378 menu "Kernel features"
380 source "kernel/Kconfig.hz"
383 bool "SBI v0.1 support"
387 This config allows kernel to use SBI v0.1 APIs. This will be
388 deprecated in future once legacy M-mode software are no longer in use.
394 string "Built-in kernel command line"
396 For most platforms, the arguments for the kernel's command line
397 are provided at run-time, during boot. However, there are cases
398 where either no arguments are being provided or the provided
399 arguments are insufficient or even invalid.
401 When that occurs, it is possible to define a built-in command
402 line here and choose how the kernel should use it later on.
405 prompt "Built-in command line usage" if CMDLINE != ""
406 default CMDLINE_FALLBACK
408 Choose how the kernel will handle the provided built-in command
411 config CMDLINE_FALLBACK
412 bool "Use bootloader kernel arguments if available"
414 Use the built-in command line as fallback in case we get nothing
415 during boot. This is the default behaviour.
417 config CMDLINE_EXTEND
418 bool "Extend bootloader kernel arguments"
420 The command-line arguments provided during boot will be
421 appended to the built-in command line. This is useful in
422 cases where the provided arguments are insufficient and
423 you don't want to or cannot modify them.
427 bool "Always use the default kernel command string"
429 Always use the built-in command line, even if we get one during
430 boot. This is useful in case you need to override the provided
431 command line on systems where you don't have or want control
440 bool "UEFI runtime support"
444 select EFI_PARAMS_FROM_FDT
446 select EFI_GENERIC_STUB
447 select EFI_RUNTIME_WRAPPERS
452 This option provides support for runtime services provided
453 by UEFI firmware (such as non-volatile variables, realtime
454 clock, and platform reset). A UEFI stub is also provided to
455 allow the kernel to be booted as an EFI application. This
456 is only useful on systems that have UEFI firmware.
458 config CC_HAVE_STACKPROTECTOR_TLS
459 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
461 config STACKPROTECTOR_PER_TASK
463 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
471 menu "Power management options"
473 source "kernel/power/Kconfig"
477 source "drivers/firmware/Kconfig"