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_FORTIFY_SOURCE
24 select ARCH_HAS_GCOV_PROFILE_ALL
25 select ARCH_HAS_GIGANTIC_PAGE
27 select ARCH_HAS_MMIOWB
28 select ARCH_HAS_PTE_SPECIAL
29 select ARCH_HAS_SET_DIRECT_MAP
30 select ARCH_HAS_SET_MEMORY
31 select ARCH_HAS_STRICT_KERNEL_RWX if MMU
32 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
33 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
34 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
35 select ARCH_WANT_FRAME_POINTERS
36 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
37 select CLONE_BACKWARDS
38 select CLINT_TIMER if !MMU
41 select GENERIC_ARCH_TOPOLOGY if SMP
42 select GENERIC_ATOMIC64 if !64BIT
43 select GENERIC_EARLY_IOREMAP
44 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
45 select GENERIC_IOREMAP
46 select GENERIC_IRQ_MULTI_HANDLER
47 select GENERIC_IRQ_SHOW
48 select GENERIC_LIB_DEVMEM_IS_ALLOWED
49 select GENERIC_PCI_IOMAP
50 select GENERIC_PTDUMP if MMU
51 select GENERIC_SCHED_CLOCK
52 select GENERIC_SMP_IDLE_THREAD
53 select GENERIC_STRNCPY_FROM_USER if MMU
54 select GENERIC_STRNLEN_USER if MMU
55 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
56 select HANDLE_DOMAIN_IRQ
57 select HAVE_ARCH_AUDITSYSCALL
58 select HAVE_ARCH_JUMP_LABEL
59 select HAVE_ARCH_JUMP_LABEL_RELATIVE
60 select HAVE_ARCH_KASAN if MMU && 64BIT
61 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
63 select HAVE_ARCH_KGDB_QXFER_PKT
64 select HAVE_ARCH_MMAP_RND_BITS if MMU
65 select HAVE_ARCH_SECCOMP_FILTER
66 select HAVE_ARCH_TRACEHOOK
67 select HAVE_ASM_MODVERSIONS
68 select HAVE_CONTEXT_TRACKING
69 select HAVE_DEBUG_KMEMLEAK
70 select HAVE_DMA_CONTIGUOUS if MMU
71 select HAVE_EBPF_JIT if MMU
72 select HAVE_FUNCTION_ERROR_INJECTION
73 select HAVE_FUTEX_CMPXCHG if FUTEX
74 select HAVE_GCC_PLUGINS
75 select HAVE_GENERIC_VDSO if MMU && 64BIT
76 select HAVE_IRQ_TIME_ACCOUNTING
78 select HAVE_KPROBES_ON_FTRACE
79 select HAVE_KRETPROBES
81 select HAVE_PERF_EVENTS
83 select HAVE_PERF_USER_STACK_DUMP
84 select HAVE_REGS_AND_STACK_ACCESS_API
85 select HAVE_STACKPROTECTOR
86 select HAVE_SYSCALL_TRACEPOINTS
88 select MODULES_USE_ELF_RELA if MODULES
89 select MODULE_SECTIONS if MODULES
91 select OF_EARLY_FLATTREE
93 select PCI_DOMAINS_GENERIC if PCI
96 select RISCV_TIMER if RISCV_SBI
97 select SPARSEMEM_STATIC if 32BIT
99 select SYSCTL_EXCEPTION_TRACE
100 select THREAD_INFO_IN_TASK
101 select UACCESS_MEMCPY if !MMU
103 config ARCH_MMAP_RND_BITS_MIN
107 # max bits determined by the following formula:
108 # VA_BITS - PAGE_SHIFT - 3
109 config ARCH_MMAP_RND_BITS_MAX
110 default 24 if 64BIT # SV39 based
113 # set if we run in machine mode, cleared if we run in supervisor mode
118 # set if we are running in S-mode and can use SBI calls
121 depends on !RISCV_M_MODE
125 bool "MMU-based Paged Memory Management Support"
128 Select if you want MMU-based virtualised addressing space
129 support by paged memory management. If unsure, say 'Y'.
147 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
148 default 0x80000000 if 64BIT && !MMU
149 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
150 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
152 config ARCH_FLATMEM_ENABLE
155 config ARCH_SPARSEMEM_ENABLE
158 select SPARSEMEM_VMEMMAP_ENABLE
160 config ARCH_SELECT_MEMORY_MODEL
161 def_bool ARCH_SPARSEMEM_ENABLE
163 config ARCH_WANT_GENERAL_HUGETLB
166 config ARCH_SUPPORTS_UPROBES
169 config SYS_SUPPORTS_HUGETLBFS
173 config STACKTRACE_SUPPORT
176 config TRACE_IRQFLAGS_SUPPORT
182 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
184 config GENERIC_BUG_RELATIVE_POINTERS
187 config GENERIC_CALIBRATE_DELAY
193 config GENERIC_HWEIGHT
196 config FIX_EARLYCON_MEM
199 config PGTABLE_LEVELS
204 config LOCKDEP_SUPPORT
207 source "arch/riscv/Kconfig.socs"
215 This selects the base ISA that this kernel will target and must match
221 select GENERIC_LIB_ASHLDI3
222 select GENERIC_LIB_ASHRDI3
223 select GENERIC_LIB_LSHRDI3
224 select GENERIC_LIB_UCMPDI2
230 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
231 select HAVE_DYNAMIC_FTRACE if MMU
232 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
233 select HAVE_FTRACE_MCOUNT_RECORD
234 select HAVE_FUNCTION_GRAPH_TRACER
235 select HAVE_FUNCTION_TRACER
236 select SWIOTLB if MMU
240 # We must be able to map all physical memory into the kernel, but the compiler
241 # is still a bit more efficient when generating code if it's setup in a manner
242 # such that it can only map 2GiB of memory.
244 prompt "Kernel Code Model"
245 default CMODEL_MEDLOW if 32BIT
246 default CMODEL_MEDANY if 64BIT
249 bool "medium low code model"
251 bool "medium any code model"
254 config MODULE_SECTIONS
256 select HAVE_MOD_ARCH_SPECIFIC
259 prompt "Maximum Physical Memory"
260 default MAXPHYSMEM_1GB if 32BIT
261 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
262 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
264 config MAXPHYSMEM_1GB
267 config MAXPHYSMEM_2GB
268 depends on 64BIT && CMODEL_MEDLOW
270 config MAXPHYSMEM_128GB
271 depends on 64BIT && CMODEL_MEDANY
277 bool "Symmetric Multi-Processing"
279 This enables support for systems with more than one CPU. If
280 you say N here, the kernel will run on single and
281 multiprocessor machines, but will use only one CPU of a
282 multiprocessor machine. If you say Y here, the kernel will run
283 on many, but not all, single processor machines. On a single
284 processor machine, the kernel will run faster if you say N
287 If you don't know what to do here, say N.
290 int "Maximum number of CPUs (2-32)"
296 bool "Support for hot-pluggable CPUs"
298 select GENERIC_IRQ_MIGRATION
301 Say Y here to experiment with turning CPUs off and on. CPUs
302 can be controlled through /sys/devices/system/cpu.
304 Say N if you want to disable CPU hotplug.
315 # Common NUMA Features
317 bool "NUMA Memory Allocation and Scheduler Support"
319 select GENERIC_ARCH_NUMA
321 select ARCH_SUPPORTS_NUMA_BALANCING
323 Enable NUMA (Non-Uniform Memory Access) support.
325 The kernel will try to allocate memory used by a CPU on the
326 local memory of the CPU and add some more NUMA awareness to the kernel.
329 int "Maximum NUMA Nodes (as a power of 2)"
332 depends on NEED_MULTIPLE_NODES
334 Specify the maximum number of NUMA Nodes available on the target
335 system. Increases memory reserved to accommodate various tables.
337 config USE_PERCPU_NUMA_NODE_ID
341 config NEED_PER_CPU_EMBED_FIRST_CHUNK
346 bool "Emit compressed instructions when building Linux"
349 Adds "C" to the ISA subsets that the toolchain is allowed to emit
350 when building Linux, which results in compressed instructions in the
353 If you don't know what to do here, say Y.
355 menu "supported PMU type"
356 depends on PERF_EVENTS
358 config RISCV_BASE_PMU
359 bool "Base Performance Monitoring Unit"
362 A base PMU that serves as a reference implementation and has limited
363 feature of perf. It can run on any RISC-V machines so serves as the
364 fallback, but this option can also be disable to reduce kernel size.
372 Say N here if you want to disable all floating-point related procedure
375 If you don't know what to do here, say Y.
379 menu "Kernel features"
381 source "kernel/Kconfig.hz"
384 bool "SBI v0.1 support"
388 This config allows kernel to use SBI v0.1 APIs. This will be
389 deprecated in future once legacy M-mode software are no longer in use.
395 string "Built-in kernel command line"
397 For most platforms, the arguments for the kernel's command line
398 are provided at run-time, during boot. However, there are cases
399 where either no arguments are being provided or the provided
400 arguments are insufficient or even invalid.
402 When that occurs, it is possible to define a built-in command
403 line here and choose how the kernel should use it later on.
406 prompt "Built-in command line usage" if CMDLINE != ""
407 default CMDLINE_FALLBACK
409 Choose how the kernel will handle the provided built-in command
412 config CMDLINE_FALLBACK
413 bool "Use bootloader kernel arguments if available"
415 Use the built-in command line as fallback in case we get nothing
416 during boot. This is the default behaviour.
418 config CMDLINE_EXTEND
419 bool "Extend bootloader kernel arguments"
421 The command-line arguments provided during boot will be
422 appended to the built-in command line. This is useful in
423 cases where the provided arguments are insufficient and
424 you don't want to or cannot modify them.
428 bool "Always use the default kernel command string"
430 Always use the built-in command line, even if we get one during
431 boot. This is useful in case you need to override the provided
432 command line on systems where you don't have or want control
441 bool "UEFI runtime support"
445 select EFI_PARAMS_FROM_FDT
447 select EFI_GENERIC_STUB
448 select EFI_RUNTIME_WRAPPERS
453 This option provides support for runtime services provided
454 by UEFI firmware (such as non-volatile variables, realtime
455 clock, and platform reset). A UEFI stub is also provided to
456 allow the kernel to be booted as an EFI application. This
457 is only useful on systems that have UEFI firmware.
459 config CC_HAVE_STACKPROTECTOR_TLS
460 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
462 config STACKPROTECTOR_PER_TASK
464 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
472 menu "Power management options"
474 source "kernel/power/Kconfig"
478 source "drivers/firmware/Kconfig"