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_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
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_FORTIFY_SOURCE
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 if MMU
28 select ARCH_HAS_SET_MEMORY if MMU
29 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
30 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
31 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
32 select ARCH_HAS_UBSAN_SANITIZE_ALL
33 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
34 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
36 select ARCH_SUPPORTS_ATOMIC_RMW
37 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
38 select ARCH_SUPPORTS_HUGETLBFS if MMU
39 select ARCH_USE_MEMTEST
40 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
41 select ARCH_WANT_FRAME_POINTERS
42 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
43 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
44 select BUILDTIME_TABLE_SORT if MMU
45 select CLONE_BACKWARDS
46 select CLINT_TIMER if !MMU
48 select CPU_PM if CPU_IDLE
50 select GENERIC_ARCH_TOPOLOGY if SMP
51 select GENERIC_ATOMIC64 if !64BIT
52 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
53 select GENERIC_EARLY_IOREMAP
54 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
55 select GENERIC_IDLE_POLL_SETUP
56 select GENERIC_IOREMAP if MMU
57 select GENERIC_IRQ_MULTI_HANDLER
58 select GENERIC_IRQ_SHOW
59 select GENERIC_IRQ_SHOW_LEVEL
60 select GENERIC_LIB_DEVMEM_IS_ALLOWED
61 select GENERIC_PCI_IOMAP
62 select GENERIC_PTDUMP if MMU
63 select GENERIC_SCHED_CLOCK
64 select GENERIC_SMP_IDLE_THREAD
65 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
66 select HANDLE_DOMAIN_IRQ
67 select HAVE_ARCH_AUDITSYSCALL
68 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
69 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
70 select HAVE_ARCH_KASAN if MMU && 64BIT
71 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
72 select HAVE_ARCH_KFENCE if MMU && 64BIT
73 select HAVE_ARCH_KGDB if !XIP_KERNEL
74 select HAVE_ARCH_KGDB_QXFER_PKT
75 select HAVE_ARCH_MMAP_RND_BITS if MMU
76 select HAVE_ARCH_SECCOMP_FILTER
77 select HAVE_ARCH_TRACEHOOK
78 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
79 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
80 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
81 select HAVE_ASM_MODVERSIONS
82 select HAVE_CONTEXT_TRACKING
83 select HAVE_DEBUG_KMEMLEAK
84 select HAVE_DMA_CONTIGUOUS if MMU
85 select HAVE_EBPF_JIT if MMU
86 select HAVE_FUNCTION_ERROR_INJECTION
87 select HAVE_FUTEX_CMPXCHG if FUTEX
88 select HAVE_GCC_PLUGINS
89 select HAVE_GENERIC_VDSO if MMU && 64BIT
90 select HAVE_IRQ_TIME_ACCOUNTING
91 select HAVE_KPROBES if !XIP_KERNEL
92 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
93 select HAVE_KRETPROBES if !XIP_KERNEL
97 select HAVE_PERF_EVENTS
99 select HAVE_PERF_USER_STACK_DUMP
100 select HAVE_REGS_AND_STACK_ACCESS_API
101 select HAVE_FUNCTION_ARG_ACCESS_API
102 select HAVE_STACKPROTECTOR
103 select HAVE_SYSCALL_TRACEPOINTS
105 select IRQ_FORCED_THREADING
106 select MODULES_USE_ELF_RELA if MODULES
107 select MODULE_SECTIONS if MODULES
109 select OF_EARLY_FLATTREE
111 select PCI_DOMAINS_GENERIC if PCI
112 select PCI_MSI if PCI
114 select RISCV_TIMER if RISCV_SBI
116 select SYSCTL_EXCEPTION_TRACE
117 select THREAD_INFO_IN_TASK
118 select TRACE_IRQFLAGS_SUPPORT
119 select UACCESS_MEMCPY if !MMU
120 select ZONE_DMA32 if 64BIT
123 config ARCH_MMAP_RND_BITS_MIN
127 # max bits determined by the following formula:
128 # VA_BITS - PAGE_SHIFT - 3
129 config ARCH_MMAP_RND_BITS_MAX
130 default 24 if 64BIT # SV39 based
133 # set if we run in machine mode, cleared if we run in supervisor mode
138 # set if we are running in S-mode and can use SBI calls
141 depends on !RISCV_M_MODE
145 bool "MMU-based Paged Memory Management Support"
148 Select if you want MMU-based virtualised addressing space
149 support by paged memory management. If unsure, say 'Y'.
163 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
164 default 0x80000000 if 64BIT && !MMU
165 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
166 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
168 config KASAN_SHADOW_OFFSET
170 depends on KASAN_GENERIC
171 default 0xdfffffc800000000 if 64BIT
172 default 0xffffffff if 32BIT
174 config ARCH_FLATMEM_ENABLE
177 config ARCH_SPARSEMEM_ENABLE
180 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
181 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
183 config ARCH_SELECT_MEMORY_MODEL
184 def_bool ARCH_SPARSEMEM_ENABLE
186 config ARCH_WANT_GENERAL_HUGETLB
189 config ARCH_SUPPORTS_UPROBES
192 config STACKTRACE_SUPPORT
198 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
200 config GENERIC_BUG_RELATIVE_POINTERS
203 config GENERIC_CALIBRATE_DELAY
209 config GENERIC_HWEIGHT
212 config FIX_EARLYCON_MEM
215 config PGTABLE_LEVELS
220 config LOCKDEP_SUPPORT
223 source "arch/riscv/Kconfig.socs"
224 source "arch/riscv/Kconfig.erratas"
232 This selects the base ISA that this kernel will target and must match
238 select GENERIC_LIB_ASHLDI3
239 select GENERIC_LIB_ASHRDI3
240 select GENERIC_LIB_LSHRDI3
241 select GENERIC_LIB_UCMPDI2
247 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
248 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
249 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
250 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
251 select HAVE_FUNCTION_GRAPH_TRACER
252 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
253 select SWIOTLB if MMU
257 # We must be able to map all physical memory into the kernel, but the compiler
258 # is still a bit more efficient when generating code if it's setup in a manner
259 # such that it can only map 2GiB of memory.
261 prompt "Kernel Code Model"
262 default CMODEL_MEDLOW if 32BIT
263 default CMODEL_MEDANY if 64BIT
266 bool "medium low code model"
268 bool "medium any code model"
271 config MODULE_SECTIONS
273 select HAVE_MOD_ARCH_SPECIFIC
276 prompt "Maximum Physical Memory"
277 default MAXPHYSMEM_1GB if 32BIT
278 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
279 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
281 config MAXPHYSMEM_1GB
284 config MAXPHYSMEM_2GB
285 depends on 64BIT && CMODEL_MEDLOW
287 config MAXPHYSMEM_128GB
288 depends on 64BIT && CMODEL_MEDANY
294 bool "Symmetric Multi-Processing"
296 This enables support for systems with more than one CPU. If
297 you say N here, the kernel will run on single and
298 multiprocessor machines, but will use only one CPU of a
299 multiprocessor machine. If you say Y here, the kernel will run
300 on many, but not all, single processor machines. On a single
301 processor machine, the kernel will run faster if you say N
304 If you don't know what to do here, say N.
307 int "Maximum number of CPUs (2-32)"
313 bool "Support for hot-pluggable CPUs"
315 select GENERIC_IRQ_MIGRATION
318 Say Y here to experiment with turning CPUs off and on. CPUs
319 can be controlled through /sys/devices/system/cpu.
321 Say N if you want to disable CPU hotplug.
332 # Common NUMA Features
334 bool "NUMA Memory Allocation and Scheduler Support"
335 depends on SMP && MMU
336 select GENERIC_ARCH_NUMA
338 select ARCH_SUPPORTS_NUMA_BALANCING
340 Enable NUMA (Non-Uniform Memory Access) support.
342 The kernel will try to allocate memory used by a CPU on the
343 local memory of the CPU and add some more NUMA awareness to the kernel.
346 int "Maximum NUMA Nodes (as a power of 2)"
351 Specify the maximum number of NUMA Nodes available on the target
352 system. Increases memory reserved to accommodate various tables.
354 config USE_PERCPU_NUMA_NODE_ID
358 config NEED_PER_CPU_EMBED_FIRST_CHUNK
363 bool "Emit compressed instructions when building Linux"
366 Adds "C" to the ISA subsets that the toolchain is allowed to emit
367 when building Linux, which results in compressed instructions in the
370 If you don't know what to do here, say Y.
372 menu "supported PMU type"
373 depends on PERF_EVENTS
375 config RISCV_BASE_PMU
376 bool "Base Performance Monitoring Unit"
379 A base PMU that serves as a reference implementation and has limited
380 feature of perf. It can run on any RISC-V machines so serves as the
381 fallback, but this option can also be disable to reduce kernel size.
389 Say N here if you want to disable all floating-point related procedure
392 If you don't know what to do here, say Y.
396 menu "Kernel features"
398 source "kernel/Kconfig.hz"
401 bool "SBI v0.1 support"
405 This config allows kernel to use SBI v0.1 APIs. This will be
406 deprecated in future once legacy M-mode software are no longer in use.
409 bool "Kexec system call"
411 select HOTPLUG_CPU if SMP
414 kexec is a system call that implements the ability to shutdown your
415 current kernel, and to start another kernel. It is like a reboot
416 but it is independent of the system firmware. And like a reboot
417 you can start any kernel with it, not just Linux.
419 The name comes from the similarity to the exec system call.
422 bool "Build kdump crash kernel"
424 Generate crash dump after being started by kexec. This should
425 be normally only set in special crash dump kernels which are
426 loaded in the main kernel with kexec-tools into a specially
427 reserved region and then later executed after a crash by
430 For more details see Documentation/admin-guide/kdump/kdump.rst
437 string "Built-in kernel command line"
439 For most platforms, the arguments for the kernel's command line
440 are provided at run-time, during boot. However, there are cases
441 where either no arguments are being provided or the provided
442 arguments are insufficient or even invalid.
444 When that occurs, it is possible to define a built-in command
445 line here and choose how the kernel should use it later on.
448 prompt "Built-in command line usage" if CMDLINE != ""
449 default CMDLINE_FALLBACK
451 Choose how the kernel will handle the provided built-in command
454 config CMDLINE_FALLBACK
455 bool "Use bootloader kernel arguments if available"
457 Use the built-in command line as fallback in case we get nothing
458 during boot. This is the default behaviour.
460 config CMDLINE_EXTEND
461 bool "Extend bootloader kernel arguments"
463 The command-line arguments provided during boot will be
464 appended to the built-in command line. This is useful in
465 cases where the provided arguments are insufficient and
466 you don't want to or cannot modify them.
470 bool "Always use the default kernel command string"
472 Always use the built-in command line, even if we get one during
473 boot. This is useful in case you need to override the provided
474 command line on systems where you don't have or want control
483 bool "UEFI runtime support"
484 depends on OF && !XIP_KERNEL
487 select EFI_PARAMS_FROM_FDT
489 select EFI_GENERIC_STUB
490 select EFI_RUNTIME_WRAPPERS
495 This option provides support for runtime services provided
496 by UEFI firmware (such as non-volatile variables, realtime
497 clock, and platform reset). A UEFI stub is also provided to
498 allow the kernel to be booted as an EFI application. This
499 is only useful on systems that have UEFI firmware.
501 config CC_HAVE_STACKPROTECTOR_TLS
502 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
504 config STACKPROTECTOR_PER_TASK
506 depends on !GCC_PLUGIN_RANDSTRUCT
507 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
509 config PHYS_RAM_BASE_FIXED
510 bool "Explicitly specified physical RAM address"
514 hex "Platform Physical RAM address"
515 depends on PHYS_RAM_BASE_FIXED
518 This is the physical address of RAM in the system. It has to be
519 explicitly specified to run early relocations of read-write data
523 bool "Kernel Execute-In-Place from ROM"
524 depends on MMU && SPARSEMEM
525 # This prevents XIP from being enabled by all{yes,mod}config, which
526 # fail to build since XIP doesn't support large kernels.
527 depends on !COMPILE_TEST
528 select PHYS_RAM_BASE_FIXED
530 Execute-In-Place allows the kernel to run from non-volatile storage
531 directly addressable by the CPU, such as NOR flash. This saves RAM
532 space since the text section of the kernel is not loaded from flash
533 to RAM. Read-write sections, such as the data section and stack,
534 are still copied to RAM. The XIP kernel is not compressed since
535 it has to run directly from flash, so it will take more space to
536 store it. The flash address used to link the kernel object files,
537 and for storing it, is configuration dependent. Therefore, if you
538 say Y here, you must know the proper physical address where to
539 store the kernel image depending on your own flash memory usage.
541 Also note that the make target becomes "make xipImage" rather than
542 "make zImage" or "make Image". The final kernel binary to put in
543 ROM memory will be arch/riscv/boot/xipImage.
545 SPARSEMEM is required because the kernel text and rodata that are
546 flash resident are not backed by memmap, then any attempt to get
547 a struct page on those regions will trigger a fault.
552 hex "XIP Kernel Physical Location"
553 depends on XIP_KERNEL
556 This is the physical address in your flash memory the kernel will
557 be linked for and stored to. This address is dependent on your
565 default y if XIP_KERNEL
567 menu "Power management options"
569 source "kernel/power/Kconfig"
573 menu "CPU Power Management"
575 source "drivers/cpuidle/Kconfig"