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_USE_MEMTEST
42 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
43 select ARCH_WANT_FRAME_POINTERS
44 select ARCH_WANT_GENERAL_HUGETLB
45 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
46 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
47 select BUILDTIME_TABLE_SORT if MMU
48 select CLONE_BACKWARDS
49 select CLINT_TIMER if !MMU
51 select CPU_PM if CPU_IDLE
53 select GENERIC_ARCH_TOPOLOGY if SMP
54 select GENERIC_ATOMIC64 if !64BIT
55 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
56 select GENERIC_EARLY_IOREMAP
57 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
58 select GENERIC_IDLE_POLL_SETUP
59 select GENERIC_IOREMAP if MMU
60 select GENERIC_IRQ_MULTI_HANDLER
61 select GENERIC_IRQ_SHOW
62 select GENERIC_IRQ_SHOW_LEVEL
63 select GENERIC_LIB_DEVMEM_IS_ALLOWED
64 select GENERIC_PCI_IOMAP
65 select GENERIC_PTDUMP if MMU
66 select GENERIC_SCHED_CLOCK
67 select GENERIC_SMP_IDLE_THREAD
68 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
69 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
70 select HAVE_ARCH_AUDITSYSCALL
71 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
72 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
73 select HAVE_ARCH_KASAN if MMU && 64BIT
74 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
75 select HAVE_ARCH_KFENCE if MMU && 64BIT
76 select HAVE_ARCH_KGDB if !XIP_KERNEL
77 select HAVE_ARCH_KGDB_QXFER_PKT
78 select HAVE_ARCH_MMAP_RND_BITS if MMU
79 select HAVE_ARCH_SECCOMP_FILTER
80 select HAVE_ARCH_TRACEHOOK
81 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
82 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
83 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
84 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
85 select HAVE_ASM_MODVERSIONS
86 select HAVE_CONTEXT_TRACKING
87 select HAVE_DEBUG_KMEMLEAK
88 select HAVE_DMA_CONTIGUOUS if MMU
89 select HAVE_EBPF_JIT if MMU
90 select HAVE_FUNCTION_ERROR_INJECTION
91 select HAVE_GCC_PLUGINS
92 select HAVE_GENERIC_VDSO if MMU && 64BIT
93 select HAVE_IRQ_TIME_ACCOUNTING
94 select HAVE_KPROBES if !XIP_KERNEL
95 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
96 select HAVE_KRETPROBES if !XIP_KERNEL
100 select HAVE_PERF_EVENTS
101 select HAVE_PERF_REGS
102 select HAVE_PERF_USER_STACK_DUMP
103 select HAVE_REGS_AND_STACK_ACCESS_API
104 select HAVE_FUNCTION_ARG_ACCESS_API
105 select HAVE_STACKPROTECTOR
106 select HAVE_SYSCALL_TRACEPOINTS
109 select IRQ_FORCED_THREADING
110 select MODULES_USE_ELF_RELA if MODULES
111 select MODULE_SECTIONS if MODULES
113 select OF_EARLY_FLATTREE
115 select PCI_DOMAINS_GENERIC if PCI
116 select PCI_MSI if PCI
118 select RISCV_TIMER if RISCV_SBI
120 select SYSCTL_EXCEPTION_TRACE
121 select THREAD_INFO_IN_TASK
122 select TRACE_IRQFLAGS_SUPPORT
123 select UACCESS_MEMCPY if !MMU
124 select ZONE_DMA32 if 64BIT
126 config ARCH_MMAP_RND_BITS_MIN
130 # max bits determined by the following formula:
131 # VA_BITS - PAGE_SHIFT - 3
132 config ARCH_MMAP_RND_BITS_MAX
133 default 24 if 64BIT # SV39 based
136 # set if we run in machine mode, cleared if we run in supervisor mode
141 # set if we are running in S-mode and can use SBI calls
144 depends on !RISCV_M_MODE
148 bool "MMU-based Paged Memory Management Support"
151 Select if you want MMU-based virtualised addressing space
152 support by paged memory management. If unsure, say 'Y'.
156 default 0xC0000000 if 32BIT
157 default 0x80000000 if 64BIT && !MMU
158 default 0xff60000000000000 if 64BIT
160 config KASAN_SHADOW_OFFSET
162 depends on KASAN_GENERIC
163 default 0xdfffffff00000000 if 64BIT
164 default 0xffffffff if 32BIT
166 config ARCH_FLATMEM_ENABLE
169 config ARCH_SPARSEMEM_ENABLE
172 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
173 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
175 config ARCH_SELECT_MEMORY_MODEL
176 def_bool ARCH_SPARSEMEM_ENABLE
178 config ARCH_SUPPORTS_UPROBES
181 config STACKTRACE_SUPPORT
187 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
189 config GENERIC_BUG_RELATIVE_POINTERS
192 config GENERIC_CALIBRATE_DELAY
198 config GENERIC_HWEIGHT
201 config FIX_EARLYCON_MEM
204 config PGTABLE_LEVELS
209 config LOCKDEP_SUPPORT
212 source "arch/riscv/Kconfig.socs"
213 source "arch/riscv/Kconfig.erratas"
221 This selects the base ISA that this kernel will target and must match
227 select GENERIC_LIB_ASHLDI3
228 select GENERIC_LIB_ASHRDI3
229 select GENERIC_LIB_LSHRDI3
230 select GENERIC_LIB_UCMPDI2
236 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
237 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
238 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
239 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
240 select HAVE_FUNCTION_GRAPH_TRACER
241 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
242 select SWIOTLB if MMU
246 # We must be able to map all physical memory into the kernel, but the compiler
247 # is still a bit more efficient when generating code if it's setup in a manner
248 # such that it can only map 2GiB of memory.
250 prompt "Kernel Code Model"
251 default CMODEL_MEDLOW if 32BIT
252 default CMODEL_MEDANY if 64BIT
255 bool "medium low code model"
257 bool "medium any code model"
260 config MODULE_SECTIONS
262 select HAVE_MOD_ARCH_SPECIFIC
265 bool "Symmetric Multi-Processing"
267 This enables support for systems with more than one CPU. If
268 you say N here, the kernel will run on single and
269 multiprocessor machines, but will use only one CPU of a
270 multiprocessor machine. If you say Y here, the kernel will run
271 on many, but not all, single processor machines. On a single
272 processor machine, the kernel will run faster if you say N
275 If you don't know what to do here, say N.
278 int "Maximum number of CPUs (2-32)"
284 bool "Support for hot-pluggable CPUs"
286 select GENERIC_IRQ_MIGRATION
289 Say Y here to experiment with turning CPUs off and on. CPUs
290 can be controlled through /sys/devices/system/cpu.
292 Say N if you want to disable CPU hotplug.
303 # Common NUMA Features
305 bool "NUMA Memory Allocation and Scheduler Support"
306 depends on SMP && MMU
307 select GENERIC_ARCH_NUMA
309 select ARCH_SUPPORTS_NUMA_BALANCING
310 select USE_PERCPU_NUMA_NODE_ID
311 select NEED_PER_CPU_EMBED_FIRST_CHUNK
313 Enable NUMA (Non-Uniform Memory Access) support.
315 The kernel will try to allocate memory used by a CPU on the
316 local memory of the CPU and add some more NUMA awareness to the kernel.
319 int "Maximum NUMA Nodes (as a power of 2)"
324 Specify the maximum number of NUMA Nodes available on the target
325 system. Increases memory reserved to accommodate various tables.
328 bool "Emit compressed instructions when building Linux"
331 Adds "C" to the ISA subsets that the toolchain is allowed to emit
332 when building Linux, which results in compressed instructions in the
335 If you don't know what to do here, say Y.
341 Say N here if you want to disable all floating-point related procedure
344 If you don't know what to do here, say Y.
348 menu "Kernel features"
350 source "kernel/Kconfig.hz"
353 bool "SBI v0.1 support"
356 This config allows kernel to use SBI v0.1 APIs. This will be
357 deprecated in future once legacy M-mode software are no longer in use.
359 config RISCV_BOOT_SPINWAIT
360 bool "Spinwait booting method"
364 This enables support for booting Linux via spinwait method. In the
365 spinwait method, all cores randomly jump to Linux. One of the cores
366 gets chosen via lottery and all other keep spinning on a percpu
367 variable. This method cannot support CPU hotplug and sparse hartid
368 scheme. It should be only enabled for M-mode Linux or platforms relying
369 on older firmware without SBI HSM extension. All other platforms should
370 rely on ordered booting via SBI HSM extension which gets chosen
371 dynamically at runtime if the firmware supports it.
374 bool "Kexec system call"
376 select HOTPLUG_CPU if SMP
379 kexec is a system call that implements the ability to shutdown your
380 current kernel, and to start another kernel. It is like a reboot
381 but it is independent of the system firmware. And like a reboot
382 you can start any kernel with it, not just Linux.
384 The name comes from the similarity to the exec system call.
387 bool "Build kdump crash kernel"
389 Generate crash dump after being started by kexec. This should
390 be normally only set in special crash dump kernels which are
391 loaded in the main kernel with kexec-tools into a specially
392 reserved region and then later executed after a crash by
395 For more details see Documentation/admin-guide/kdump/kdump.rst
402 string "Built-in kernel command line"
404 For most platforms, the arguments for the kernel's command line
405 are provided at run-time, during boot. However, there are cases
406 where either no arguments are being provided or the provided
407 arguments are insufficient or even invalid.
409 When that occurs, it is possible to define a built-in command
410 line here and choose how the kernel should use it later on.
413 prompt "Built-in command line usage" if CMDLINE != ""
414 default CMDLINE_FALLBACK
416 Choose how the kernel will handle the provided built-in command
419 config CMDLINE_FALLBACK
420 bool "Use bootloader kernel arguments if available"
422 Use the built-in command line as fallback in case we get nothing
423 during boot. This is the default behaviour.
425 config CMDLINE_EXTEND
426 bool "Extend bootloader kernel arguments"
428 The command-line arguments provided during boot will be
429 appended to the built-in command line. This is useful in
430 cases where the provided arguments are insufficient and
431 you don't want to or cannot modify them.
435 bool "Always use the default kernel command string"
437 Always use the built-in command line, even if we get one during
438 boot. This is useful in case you need to override the provided
439 command line on systems where you don't have or want control
448 bool "UEFI runtime support"
449 depends on OF && !XIP_KERNEL
452 select EFI_PARAMS_FROM_FDT
454 select EFI_GENERIC_STUB
455 select EFI_RUNTIME_WRAPPERS
460 This option provides support for runtime services provided
461 by UEFI firmware (such as non-volatile variables, realtime
462 clock, and platform reset). A UEFI stub is also provided to
463 allow the kernel to be booted as an EFI application. This
464 is only useful on systems that have UEFI firmware.
466 config CC_HAVE_STACKPROTECTOR_TLS
467 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
469 config STACKPROTECTOR_PER_TASK
471 depends on !GCC_PLUGIN_RANDSTRUCT
472 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
474 config PHYS_RAM_BASE_FIXED
475 bool "Explicitly specified physical RAM address"
479 hex "Platform Physical RAM address"
480 depends on PHYS_RAM_BASE_FIXED
483 This is the physical address of RAM in the system. It has to be
484 explicitly specified to run early relocations of read-write data
488 bool "Kernel Execute-In-Place from ROM"
489 depends on MMU && SPARSEMEM
490 # This prevents XIP from being enabled by all{yes,mod}config, which
491 # fail to build since XIP doesn't support large kernels.
492 depends on !COMPILE_TEST
493 select PHYS_RAM_BASE_FIXED
495 Execute-In-Place allows the kernel to run from non-volatile storage
496 directly addressable by the CPU, such as NOR flash. This saves RAM
497 space since the text section of the kernel is not loaded from flash
498 to RAM. Read-write sections, such as the data section and stack,
499 are still copied to RAM. The XIP kernel is not compressed since
500 it has to run directly from flash, so it will take more space to
501 store it. The flash address used to link the kernel object files,
502 and for storing it, is configuration dependent. Therefore, if you
503 say Y here, you must know the proper physical address where to
504 store the kernel image depending on your own flash memory usage.
506 Also note that the make target becomes "make xipImage" rather than
507 "make zImage" or "make Image". The final kernel binary to put in
508 ROM memory will be arch/riscv/boot/xipImage.
510 SPARSEMEM is required because the kernel text and rodata that are
511 flash resident are not backed by memmap, then any attempt to get
512 a struct page on those regions will trigger a fault.
517 hex "XIP Kernel Physical Location"
518 depends on XIP_KERNEL
521 This is the physical address in your flash memory the kernel will
522 be linked for and stored to. This address is dependent on your
530 default y if XIP_KERNEL
532 menu "Power management options"
534 source "kernel/power/Kconfig"
538 menu "CPU Power Management"
540 source "drivers/cpuidle/Kconfig"
544 source "arch/riscv/kvm/Kconfig"