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
49 select GENERIC_ARCH_TOPOLOGY if SMP
50 select GENERIC_ATOMIC64 if !64BIT
51 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
52 select GENERIC_EARLY_IOREMAP
53 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
54 select GENERIC_IDLE_POLL_SETUP
55 select GENERIC_IOREMAP if MMU
56 select GENERIC_IRQ_MULTI_HANDLER
57 select GENERIC_IRQ_SHOW
58 select GENERIC_IRQ_SHOW_LEVEL
59 select GENERIC_LIB_DEVMEM_IS_ALLOWED
60 select GENERIC_PCI_IOMAP
61 select GENERIC_PTDUMP if MMU
62 select GENERIC_SCHED_CLOCK
63 select GENERIC_SMP_IDLE_THREAD
64 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
65 select HAVE_ARCH_AUDITSYSCALL
66 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
67 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
68 select HAVE_ARCH_KASAN if MMU && 64BIT
69 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
70 select HAVE_ARCH_KFENCE if MMU && 64BIT
71 select HAVE_ARCH_KGDB if !XIP_KERNEL
72 select HAVE_ARCH_KGDB_QXFER_PKT
73 select HAVE_ARCH_MMAP_RND_BITS if MMU
74 select HAVE_ARCH_SECCOMP_FILTER
75 select HAVE_ARCH_TRACEHOOK
76 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
77 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
78 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
79 select HAVE_ASM_MODVERSIONS
80 select HAVE_CONTEXT_TRACKING
81 select HAVE_DEBUG_KMEMLEAK
82 select HAVE_DMA_CONTIGUOUS if MMU
83 select HAVE_EBPF_JIT if MMU
84 select HAVE_FUNCTION_ERROR_INJECTION
85 select HAVE_FUTEX_CMPXCHG if FUTEX
86 select HAVE_GCC_PLUGINS
87 select HAVE_GENERIC_VDSO if MMU && 64BIT
88 select HAVE_IRQ_TIME_ACCOUNTING
89 select HAVE_KPROBES if !XIP_KERNEL
90 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
91 select HAVE_KRETPROBES if !XIP_KERNEL
95 select HAVE_PERF_EVENTS
97 select HAVE_PERF_USER_STACK_DUMP
98 select HAVE_REGS_AND_STACK_ACCESS_API
99 select HAVE_FUNCTION_ARG_ACCESS_API
100 select HAVE_STACKPROTECTOR
101 select HAVE_SYSCALL_TRACEPOINTS
103 select IRQ_FORCED_THREADING
104 select MODULES_USE_ELF_RELA if MODULES
105 select MODULE_SECTIONS if MODULES
107 select OF_EARLY_FLATTREE
109 select PCI_DOMAINS_GENERIC if PCI
110 select PCI_MSI if PCI
112 select RISCV_TIMER if RISCV_SBI
114 select SYSCTL_EXCEPTION_TRACE
115 select THREAD_INFO_IN_TASK
116 select TRACE_IRQFLAGS_SUPPORT
117 select UACCESS_MEMCPY if !MMU
118 select ZONE_DMA32 if 64BIT
120 config ARCH_MMAP_RND_BITS_MIN
124 # max bits determined by the following formula:
125 # VA_BITS - PAGE_SHIFT - 3
126 config ARCH_MMAP_RND_BITS_MAX
127 default 24 if 64BIT # SV39 based
130 # set if we run in machine mode, cleared if we run in supervisor mode
135 # set if we are running in S-mode and can use SBI calls
138 depends on !RISCV_M_MODE
142 bool "MMU-based Paged Memory Management Support"
145 Select if you want MMU-based virtualised addressing space
146 support by paged memory management. If unsure, say 'Y'.
160 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
161 default 0x80000000 if 64BIT && !MMU
162 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
163 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
165 config KASAN_SHADOW_OFFSET
167 depends on KASAN_GENERIC
168 default 0xdfffffc800000000 if 64BIT
169 default 0xffffffff if 32BIT
171 config ARCH_FLATMEM_ENABLE
174 config ARCH_SPARSEMEM_ENABLE
177 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
178 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
180 config ARCH_SELECT_MEMORY_MODEL
181 def_bool ARCH_SPARSEMEM_ENABLE
183 config ARCH_WANT_GENERAL_HUGETLB
186 config ARCH_SUPPORTS_UPROBES
189 config STACKTRACE_SUPPORT
195 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
197 config GENERIC_BUG_RELATIVE_POINTERS
200 config GENERIC_CALIBRATE_DELAY
206 config GENERIC_HWEIGHT
209 config FIX_EARLYCON_MEM
212 config PGTABLE_LEVELS
217 config LOCKDEP_SUPPORT
220 source "arch/riscv/Kconfig.socs"
221 source "arch/riscv/Kconfig.erratas"
229 This selects the base ISA that this kernel will target and must match
235 select GENERIC_LIB_ASHLDI3
236 select GENERIC_LIB_ASHRDI3
237 select GENERIC_LIB_LSHRDI3
238 select GENERIC_LIB_UCMPDI2
244 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
245 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
246 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
247 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
248 select HAVE_FUNCTION_GRAPH_TRACER
249 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
250 select SWIOTLB if MMU
254 # We must be able to map all physical memory into the kernel, but the compiler
255 # is still a bit more efficient when generating code if it's setup in a manner
256 # such that it can only map 2GiB of memory.
258 prompt "Kernel Code Model"
259 default CMODEL_MEDLOW if 32BIT
260 default CMODEL_MEDANY if 64BIT
263 bool "medium low code model"
265 bool "medium any code model"
268 config MODULE_SECTIONS
270 select HAVE_MOD_ARCH_SPECIFIC
273 prompt "Maximum Physical Memory"
274 default MAXPHYSMEM_1GB if 32BIT
275 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
276 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
278 config MAXPHYSMEM_1GB
281 config MAXPHYSMEM_2GB
282 depends on 64BIT && CMODEL_MEDLOW
284 config MAXPHYSMEM_128GB
285 depends on 64BIT && CMODEL_MEDANY
291 bool "Symmetric Multi-Processing"
293 This enables support for systems with more than one CPU. If
294 you say N here, the kernel will run on single and
295 multiprocessor machines, but will use only one CPU of a
296 multiprocessor machine. If you say Y here, the kernel will run
297 on many, but not all, single processor machines. On a single
298 processor machine, the kernel will run faster if you say N
301 If you don't know what to do here, say N.
304 int "Maximum number of CPUs (2-32)"
310 bool "Support for hot-pluggable CPUs"
312 select GENERIC_IRQ_MIGRATION
315 Say Y here to experiment with turning CPUs off and on. CPUs
316 can be controlled through /sys/devices/system/cpu.
318 Say N if you want to disable CPU hotplug.
329 # Common NUMA Features
331 bool "NUMA Memory Allocation and Scheduler Support"
332 depends on SMP && MMU
333 select GENERIC_ARCH_NUMA
335 select ARCH_SUPPORTS_NUMA_BALANCING
337 Enable NUMA (Non-Uniform Memory Access) support.
339 The kernel will try to allocate memory used by a CPU on the
340 local memory of the CPU and add some more NUMA awareness to the kernel.
343 int "Maximum NUMA Nodes (as a power of 2)"
348 Specify the maximum number of NUMA Nodes available on the target
349 system. Increases memory reserved to accommodate various tables.
351 config USE_PERCPU_NUMA_NODE_ID
355 config NEED_PER_CPU_EMBED_FIRST_CHUNK
360 bool "Emit compressed instructions when building Linux"
363 Adds "C" to the ISA subsets that the toolchain is allowed to emit
364 when building Linux, which results in compressed instructions in the
367 If you don't know what to do here, say Y.
369 menu "supported PMU type"
370 depends on PERF_EVENTS
372 config RISCV_BASE_PMU
373 bool "Base Performance Monitoring Unit"
376 A base PMU that serves as a reference implementation and has limited
377 feature of perf. It can run on any RISC-V machines so serves as the
378 fallback, but this option can also be disable to reduce kernel size.
386 Say N here if you want to disable all floating-point related procedure
389 If you don't know what to do here, say Y.
393 menu "Kernel features"
395 source "kernel/Kconfig.hz"
398 bool "SBI v0.1 support"
402 This config allows kernel to use SBI v0.1 APIs. This will be
403 deprecated in future once legacy M-mode software are no longer in use.
406 bool "Kexec system call"
408 select HOTPLUG_CPU if SMP
411 kexec is a system call that implements the ability to shutdown your
412 current kernel, and to start another kernel. It is like a reboot
413 but it is independent of the system firmware. And like a reboot
414 you can start any kernel with it, not just Linux.
416 The name comes from the similarity to the exec system call.
419 bool "Build kdump crash kernel"
421 Generate crash dump after being started by kexec. This should
422 be normally only set in special crash dump kernels which are
423 loaded in the main kernel with kexec-tools into a specially
424 reserved region and then later executed after a crash by
427 For more details see Documentation/admin-guide/kdump/kdump.rst
434 string "Built-in kernel command line"
436 For most platforms, the arguments for the kernel's command line
437 are provided at run-time, during boot. However, there are cases
438 where either no arguments are being provided or the provided
439 arguments are insufficient or even invalid.
441 When that occurs, it is possible to define a built-in command
442 line here and choose how the kernel should use it later on.
445 prompt "Built-in command line usage" if CMDLINE != ""
446 default CMDLINE_FALLBACK
448 Choose how the kernel will handle the provided built-in command
451 config CMDLINE_FALLBACK
452 bool "Use bootloader kernel arguments if available"
454 Use the built-in command line as fallback in case we get nothing
455 during boot. This is the default behaviour.
457 config CMDLINE_EXTEND
458 bool "Extend bootloader kernel arguments"
460 The command-line arguments provided during boot will be
461 appended to the built-in command line. This is useful in
462 cases where the provided arguments are insufficient and
463 you don't want to or cannot modify them.
467 bool "Always use the default kernel command string"
469 Always use the built-in command line, even if we get one during
470 boot. This is useful in case you need to override the provided
471 command line on systems where you don't have or want control
480 bool "UEFI runtime support"
481 depends on OF && !XIP_KERNEL
484 select EFI_PARAMS_FROM_FDT
486 select EFI_GENERIC_STUB
487 select EFI_RUNTIME_WRAPPERS
492 This option provides support for runtime services provided
493 by UEFI firmware (such as non-volatile variables, realtime
494 clock, and platform reset). A UEFI stub is also provided to
495 allow the kernel to be booted as an EFI application. This
496 is only useful on systems that have UEFI firmware.
498 config CC_HAVE_STACKPROTECTOR_TLS
499 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
501 config STACKPROTECTOR_PER_TASK
503 depends on !GCC_PLUGIN_RANDSTRUCT
504 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
506 config PHYS_RAM_BASE_FIXED
507 bool "Explicitly specified physical RAM address"
511 hex "Platform Physical RAM address"
512 depends on PHYS_RAM_BASE_FIXED
515 This is the physical address of RAM in the system. It has to be
516 explicitly specified to run early relocations of read-write data
520 bool "Kernel Execute-In-Place from ROM"
521 depends on MMU && SPARSEMEM
522 # This prevents XIP from being enabled by all{yes,mod}config, which
523 # fail to build since XIP doesn't support large kernels.
524 depends on !COMPILE_TEST
525 select PHYS_RAM_BASE_FIXED
527 Execute-In-Place allows the kernel to run from non-volatile storage
528 directly addressable by the CPU, such as NOR flash. This saves RAM
529 space since the text section of the kernel is not loaded from flash
530 to RAM. Read-write sections, such as the data section and stack,
531 are still copied to RAM. The XIP kernel is not compressed since
532 it has to run directly from flash, so it will take more space to
533 store it. The flash address used to link the kernel object files,
534 and for storing it, is configuration dependent. Therefore, if you
535 say Y here, you must know the proper physical address where to
536 store the kernel image depending on your own flash memory usage.
538 Also note that the make target becomes "make xipImage" rather than
539 "make zImage" or "make Image". The final kernel binary to put in
540 ROM memory will be arch/riscv/boot/xipImage.
542 SPARSEMEM is required because the kernel text and rodata that are
543 flash resident are not backed by memmap, then any attempt to get
544 a struct page on those regions will trigger a fault.
549 hex "XIP Kernel Physical Location"
550 depends on XIP_KERNEL
553 This is the physical address in your flash memory the kernel will
554 be linked for and stored to. This address is dependent on your
562 default y if XIP_KERNEL
564 menu "Power management options"
566 source "kernel/power/Kconfig"
570 source "arch/riscv/kvm/Kconfig"