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_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
18 select ARCH_HAS_BINFMT_FLAT
19 select ARCH_HAS_CURRENT_STACK_POINTER
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 if MMU
30 select ARCH_HAS_SET_MEMORY if MMU
31 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
32 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
33 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
34 select ARCH_HAS_UBSAN_SANITIZE_ALL
35 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
36 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
38 select ARCH_SUPPORTS_ATOMIC_RMW
39 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
40 select ARCH_SUPPORTS_HUGETLBFS if MMU
41 select ARCH_SUPPORTS_PAGE_TABLE_CHECK
42 select ARCH_USE_MEMTEST
43 select ARCH_USE_QUEUED_RWLOCKS
44 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
45 select ARCH_WANT_FRAME_POINTERS
46 select ARCH_WANT_GENERAL_HUGETLB
47 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
48 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
49 select BUILDTIME_TABLE_SORT if MMU
50 select CLONE_BACKWARDS
51 select CLINT_TIMER if !MMU
53 select CPU_PM if CPU_IDLE
55 select GENERIC_ARCH_TOPOLOGY if SMP
56 select GENERIC_ATOMIC64 if !64BIT
57 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
58 select GENERIC_EARLY_IOREMAP
59 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
60 select GENERIC_IDLE_POLL_SETUP
61 select GENERIC_IOREMAP if MMU
62 select GENERIC_IRQ_MULTI_HANDLER
63 select GENERIC_IRQ_SHOW
64 select GENERIC_IRQ_SHOW_LEVEL
65 select GENERIC_LIB_DEVMEM_IS_ALLOWED
66 select GENERIC_PCI_IOMAP
67 select GENERIC_PTDUMP if MMU
68 select GENERIC_SCHED_CLOCK
69 select GENERIC_SMP_IDLE_THREAD
70 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
71 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
72 select HAVE_ARCH_AUDITSYSCALL
73 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
74 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
75 select HAVE_ARCH_KASAN if MMU && 64BIT
76 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
77 select HAVE_ARCH_KFENCE if MMU && 64BIT
78 select HAVE_ARCH_KGDB if !XIP_KERNEL
79 select HAVE_ARCH_KGDB_QXFER_PKT
80 select HAVE_ARCH_MMAP_RND_BITS if MMU
81 select HAVE_ARCH_SECCOMP_FILTER
82 select HAVE_ARCH_TRACEHOOK
83 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
84 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
85 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
86 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
87 select HAVE_ASM_MODVERSIONS
88 select HAVE_CONTEXT_TRACKING
89 select HAVE_DEBUG_KMEMLEAK
90 select HAVE_DMA_CONTIGUOUS if MMU
91 select HAVE_EBPF_JIT if MMU
92 select HAVE_FUNCTION_ERROR_INJECTION
93 select HAVE_GCC_PLUGINS
94 select HAVE_GENERIC_VDSO if MMU && 64BIT
95 select HAVE_IRQ_TIME_ACCOUNTING
96 select HAVE_KPROBES if !XIP_KERNEL
97 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
98 select HAVE_KRETPROBES if !XIP_KERNEL
102 select HAVE_PERF_EVENTS
103 select HAVE_PERF_REGS
104 select HAVE_PERF_USER_STACK_DUMP
105 select HAVE_REGS_AND_STACK_ACCESS_API
106 select HAVE_FUNCTION_ARG_ACCESS_API
107 select HAVE_STACKPROTECTOR
108 select HAVE_SYSCALL_TRACEPOINTS
111 select IRQ_FORCED_THREADING
112 select MODULES_USE_ELF_RELA if MODULES
113 select MODULE_SECTIONS if MODULES
115 select OF_EARLY_FLATTREE
117 select PCI_DOMAINS_GENERIC if PCI
118 select PCI_MSI if PCI
120 select RISCV_TIMER if RISCV_SBI
122 select SYSCTL_EXCEPTION_TRACE
123 select THREAD_INFO_IN_TASK
124 select TRACE_IRQFLAGS_SUPPORT
125 select UACCESS_MEMCPY if !MMU
126 select ZONE_DMA32 if 64BIT
128 config ARCH_MMAP_RND_BITS_MIN
132 # max bits determined by the following formula:
133 # VA_BITS - PAGE_SHIFT - 3
134 config ARCH_MMAP_RND_BITS_MAX
135 default 24 if 64BIT # SV39 based
138 # set if we run in machine mode, cleared if we run in supervisor mode
143 # set if we are running in S-mode and can use SBI calls
146 depends on !RISCV_M_MODE
150 bool "MMU-based Paged Memory Management Support"
153 Select if you want MMU-based virtualised addressing space
154 support by paged memory management. If unsure, say 'Y'.
158 default 0xC0000000 if 32BIT
159 default 0x80000000 if 64BIT && !MMU
160 default 0xff60000000000000 if 64BIT
162 config KASAN_SHADOW_OFFSET
164 depends on KASAN_GENERIC
165 default 0xdfffffff00000000 if 64BIT
166 default 0xffffffff if 32BIT
168 config ARCH_FLATMEM_ENABLE
171 config ARCH_SPARSEMEM_ENABLE
174 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
175 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
177 config ARCH_SELECT_MEMORY_MODEL
178 def_bool ARCH_SPARSEMEM_ENABLE
180 config ARCH_SUPPORTS_UPROBES
183 config STACKTRACE_SUPPORT
189 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
191 config GENERIC_BUG_RELATIVE_POINTERS
194 config GENERIC_CALIBRATE_DELAY
200 config GENERIC_HWEIGHT
203 config FIX_EARLYCON_MEM
206 config PGTABLE_LEVELS
211 config LOCKDEP_SUPPORT
214 source "arch/riscv/Kconfig.socs"
215 source "arch/riscv/Kconfig.erratas"
223 This selects the base ISA that this kernel will target and must match
229 select GENERIC_LIB_ASHLDI3
230 select GENERIC_LIB_ASHRDI3
231 select GENERIC_LIB_LSHRDI3
232 select GENERIC_LIB_UCMPDI2
238 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
239 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
240 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
241 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
242 select HAVE_FUNCTION_GRAPH_TRACER
243 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
244 select SWIOTLB if MMU
248 # We must be able to map all physical memory into the kernel, but the compiler
249 # is still a bit more efficient when generating code if it's setup in a manner
250 # such that it can only map 2GiB of memory.
252 prompt "Kernel Code Model"
253 default CMODEL_MEDLOW if 32BIT
254 default CMODEL_MEDANY if 64BIT
257 bool "medium low code model"
259 bool "medium any code model"
262 config MODULE_SECTIONS
264 select HAVE_MOD_ARCH_SPECIFIC
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 depends on SMP && MMU
309 select GENERIC_ARCH_NUMA
311 select ARCH_SUPPORTS_NUMA_BALANCING
312 select USE_PERCPU_NUMA_NODE_ID
313 select NEED_PER_CPU_EMBED_FIRST_CHUNK
315 Enable NUMA (Non-Uniform Memory Access) support.
317 The kernel will try to allocate memory used by a CPU on the
318 local memory of the CPU and add some more NUMA awareness to the kernel.
321 int "Maximum NUMA Nodes (as a power of 2)"
326 Specify the maximum number of NUMA Nodes available on the target
327 system. Increases memory reserved to accommodate various tables.
330 bool "Emit compressed instructions when building Linux"
333 Adds "C" to the ISA subsets that the toolchain is allowed to emit
334 when building Linux, which results in compressed instructions in the
337 If you don't know what to do here, say Y.
343 Say N here if you want to disable all floating-point related procedure
346 If you don't know what to do here, say Y.
350 menu "Kernel features"
352 source "kernel/Kconfig.hz"
355 bool "SBI v0.1 support"
358 This config allows kernel to use SBI v0.1 APIs. This will be
359 deprecated in future once legacy M-mode software are no longer in use.
361 config RISCV_BOOT_SPINWAIT
362 bool "Spinwait booting method"
366 This enables support for booting Linux via spinwait method. In the
367 spinwait method, all cores randomly jump to Linux. One of the cores
368 gets chosen via lottery and all other keep spinning on a percpu
369 variable. This method cannot support CPU hotplug and sparse hartid
370 scheme. It should be only enabled for M-mode Linux or platforms relying
371 on older firmware without SBI HSM extension. All other platforms should
372 rely on ordered booting via SBI HSM extension which gets chosen
373 dynamically at runtime if the firmware supports it.
376 bool "Kexec system call"
378 select HOTPLUG_CPU if SMP
381 kexec is a system call that implements the ability to shutdown your
382 current kernel, and to start another kernel. It is like a reboot
383 but it is independent of the system firmware. And like a reboot
384 you can start any kernel with it, not just Linux.
386 The name comes from the similarity to the exec system call.
389 bool "Build kdump crash kernel"
391 Generate crash dump after being started by kexec. This should
392 be normally only set in special crash dump kernels which are
393 loaded in the main kernel with kexec-tools into a specially
394 reserved region and then later executed after a crash by
397 For more details see Documentation/admin-guide/kdump/kdump.rst
404 string "Built-in kernel command line"
406 For most platforms, the arguments for the kernel's command line
407 are provided at run-time, during boot. However, there are cases
408 where either no arguments are being provided or the provided
409 arguments are insufficient or even invalid.
411 When that occurs, it is possible to define a built-in command
412 line here and choose how the kernel should use it later on.
415 prompt "Built-in command line usage" if CMDLINE != ""
416 default CMDLINE_FALLBACK
418 Choose how the kernel will handle the provided built-in command
421 config CMDLINE_FALLBACK
422 bool "Use bootloader kernel arguments if available"
424 Use the built-in command line as fallback in case we get nothing
425 during boot. This is the default behaviour.
427 config CMDLINE_EXTEND
428 bool "Extend bootloader kernel arguments"
430 The command-line arguments provided during boot will be
431 appended to the built-in command line. This is useful in
432 cases where the provided arguments are insufficient and
433 you don't want to or cannot modify them.
437 bool "Always use the default kernel command string"
439 Always use the built-in command line, even if we get one during
440 boot. This is useful in case you need to override the provided
441 command line on systems where you don't have or want control
450 bool "UEFI runtime support"
451 depends on OF && !XIP_KERNEL
454 select EFI_PARAMS_FROM_FDT
456 select EFI_GENERIC_STUB
457 select EFI_RUNTIME_WRAPPERS
462 This option provides support for runtime services provided
463 by UEFI firmware (such as non-volatile variables, realtime
464 clock, and platform reset). A UEFI stub is also provided to
465 allow the kernel to be booted as an EFI application. This
466 is only useful on systems that have UEFI firmware.
468 config CC_HAVE_STACKPROTECTOR_TLS
469 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
471 config STACKPROTECTOR_PER_TASK
473 depends on !RANDSTRUCT
474 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
476 config PHYS_RAM_BASE_FIXED
477 bool "Explicitly specified physical RAM address"
481 hex "Platform Physical RAM address"
482 depends on PHYS_RAM_BASE_FIXED
485 This is the physical address of RAM in the system. It has to be
486 explicitly specified to run early relocations of read-write data
490 bool "Kernel Execute-In-Place from ROM"
491 depends on MMU && SPARSEMEM
492 # This prevents XIP from being enabled by all{yes,mod}config, which
493 # fail to build since XIP doesn't support large kernels.
494 depends on !COMPILE_TEST
495 select PHYS_RAM_BASE_FIXED
497 Execute-In-Place allows the kernel to run from non-volatile storage
498 directly addressable by the CPU, such as NOR flash. This saves RAM
499 space since the text section of the kernel is not loaded from flash
500 to RAM. Read-write sections, such as the data section and stack,
501 are still copied to RAM. The XIP kernel is not compressed since
502 it has to run directly from flash, so it will take more space to
503 store it. The flash address used to link the kernel object files,
504 and for storing it, is configuration dependent. Therefore, if you
505 say Y here, you must know the proper physical address where to
506 store the kernel image depending on your own flash memory usage.
508 Also note that the make target becomes "make xipImage" rather than
509 "make zImage" or "make Image". The final kernel binary to put in
510 ROM memory will be arch/riscv/boot/xipImage.
512 SPARSEMEM is required because the kernel text and rodata that are
513 flash resident are not backed by memmap, then any attempt to get
514 a struct page on those regions will trigger a fault.
519 hex "XIP Kernel Physical Location"
520 depends on XIP_KERNEL
523 This is the physical address in your flash memory the kernel will
524 be linked for and stored to. This address is dependent on your
532 default y if XIP_KERNEL
534 menu "Power management options"
536 source "kernel/power/Kconfig"
540 menu "CPU Power Management"
542 source "drivers/cpuidle/Kconfig"
546 source "arch/riscv/kvm/Kconfig"