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_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
16 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
17 select ARCH_HAS_BINFMT_FLAT
18 select ARCH_HAS_CURRENT_STACK_POINTER
19 select ARCH_HAS_DEBUG_VM_PGTABLE
20 select ARCH_HAS_DEBUG_VIRTUAL if MMU
21 select ARCH_HAS_DEBUG_WX
22 select ARCH_HAS_FORTIFY_SOURCE
23 select ARCH_HAS_GCOV_PROFILE_ALL
24 select ARCH_HAS_GIGANTIC_PAGE
26 select ARCH_HAS_MMIOWB
27 select ARCH_HAS_PMEM_API
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 if MMU
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 ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
49 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
50 select BUILDTIME_TABLE_SORT if MMU
51 select CLONE_BACKWARDS
52 select CLINT_TIMER if !MMU
54 select CPU_PM if CPU_IDLE
56 select GENERIC_ARCH_TOPOLOGY
57 select GENERIC_ATOMIC64 if !64BIT
58 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
59 select GENERIC_EARLY_IOREMAP
60 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
61 select GENERIC_IDLE_POLL_SETUP
62 select GENERIC_IOREMAP if MMU
63 select GENERIC_IRQ_MULTI_HANDLER
64 select GENERIC_IRQ_SHOW
65 select GENERIC_IRQ_SHOW_LEVEL
66 select GENERIC_LIB_DEVMEM_IS_ALLOWED
67 select GENERIC_PCI_IOMAP
68 select GENERIC_PTDUMP if MMU
69 select GENERIC_SCHED_CLOCK
70 select GENERIC_SMP_IDLE_THREAD
71 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
72 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
73 select HARDIRQS_SW_RESEND
74 select HAVE_ARCH_AUDITSYSCALL
75 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
76 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
77 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
78 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
79 select HAVE_ARCH_KASAN if MMU && 64BIT
80 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
81 select HAVE_ARCH_KFENCE if MMU && 64BIT
82 select HAVE_ARCH_KGDB if !XIP_KERNEL
83 select HAVE_ARCH_KGDB_QXFER_PKT
84 select HAVE_ARCH_MMAP_RND_BITS if MMU
85 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
86 select HAVE_ARCH_SECCOMP_FILTER
87 select HAVE_ARCH_TRACEHOOK
88 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
89 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
90 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
91 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
92 select HAVE_ASM_MODVERSIONS
93 select HAVE_CONTEXT_TRACKING_USER
94 select HAVE_DEBUG_KMEMLEAK
95 select HAVE_DMA_CONTIGUOUS if MMU
96 select HAVE_EBPF_JIT if MMU
97 select HAVE_FUNCTION_ERROR_INJECTION
98 select HAVE_GCC_PLUGINS
99 select HAVE_GENERIC_VDSO if MMU && 64BIT
100 select HAVE_IRQ_TIME_ACCOUNTING
101 select HAVE_KPROBES if !XIP_KERNEL
102 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
103 select HAVE_KRETPROBES if !XIP_KERNEL
104 select HAVE_RETHOOK if !XIP_KERNEL
108 select HAVE_PERF_EVENTS
109 select HAVE_PERF_REGS
110 select HAVE_PERF_USER_STACK_DUMP
111 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
112 select HAVE_REGS_AND_STACK_ACCESS_API
113 select HAVE_FUNCTION_ARG_ACCESS_API
114 select HAVE_STACKPROTECTOR
115 select HAVE_SYSCALL_TRACEPOINTS
118 select IRQ_FORCED_THREADING
119 select MODULES_USE_ELF_RELA if MODULES
120 select MODULE_SECTIONS if MODULES
122 select OF_DMA_DEFAULT_COHERENT
123 select OF_EARLY_FLATTREE
125 select PCI_DOMAINS_GENERIC if PCI
126 select PCI_MSI if PCI
128 select RISCV_TIMER if RISCV_SBI
131 select SYSCTL_EXCEPTION_TRACE
132 select THREAD_INFO_IN_TASK
133 select TRACE_IRQFLAGS_SUPPORT
134 select UACCESS_MEMCPY if !MMU
135 select ZONE_DMA32 if 64BIT
136 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
137 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
138 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
139 select HAVE_FUNCTION_GRAPH_TRACER
140 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
142 config ARCH_MMAP_RND_BITS_MIN
146 config ARCH_MMAP_RND_COMPAT_BITS_MIN
149 # max bits determined by the following formula:
150 # VA_BITS - PAGE_SHIFT - 3
151 config ARCH_MMAP_RND_BITS_MAX
152 default 24 if 64BIT # SV39 based
155 config ARCH_MMAP_RND_COMPAT_BITS_MAX
158 # set if we run in machine mode, cleared if we run in supervisor mode
163 # set if we are running in S-mode and can use SBI calls
166 depends on !RISCV_M_MODE
170 bool "MMU-based Paged Memory Management Support"
173 Select if you want MMU-based virtualised addressing space
174 support by paged memory management. If unsure, say 'Y'.
178 default 0xC0000000 if 32BIT
179 default 0x80000000 if 64BIT && !MMU
180 default 0xff60000000000000 if 64BIT
182 config KASAN_SHADOW_OFFSET
184 depends on KASAN_GENERIC
185 default 0xdfffffff00000000 if 64BIT
186 default 0xffffffff if 32BIT
188 config ARCH_FLATMEM_ENABLE
191 config ARCH_SPARSEMEM_ENABLE
194 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
195 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
197 config ARCH_SELECT_MEMORY_MODEL
198 def_bool ARCH_SPARSEMEM_ENABLE
200 config ARCH_SUPPORTS_UPROBES
203 config STACKTRACE_SUPPORT
209 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
211 config GENERIC_BUG_RELATIVE_POINTERS
214 config GENERIC_CALIBRATE_DELAY
220 config GENERIC_HWEIGHT
223 config FIX_EARLYCON_MEM
226 config PGTABLE_LEVELS
231 config LOCKDEP_SUPPORT
234 config RISCV_DMA_NONCOHERENT
236 select ARCH_HAS_DMA_PREP_COHERENT
237 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
238 select ARCH_HAS_SYNC_DMA_FOR_CPU
239 select ARCH_HAS_SETUP_DMA_OPS
240 select DMA_DIRECT_REMAP
243 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
245 source "arch/riscv/Kconfig.socs"
246 source "arch/riscv/Kconfig.erratas"
251 bool "Allow configurations that result in non-portable kernels"
253 RISC-V kernel binaries are compatible between all known systems
254 whenever possible, but there are some use cases that can only be
255 satisfied by configurations that result in kernel binaries that are
256 not portable between systems.
258 Selecting N does not guarantee kernels will be portable to all known
259 systems. Selecting any of the options guarded by NONPORTABLE will
260 result in kernel binaries that are unlikely to be portable between
269 This selects the base ISA that this kernel will target and must match
274 depends on NONPORTABLE
276 select GENERIC_LIB_ASHLDI3
277 select GENERIC_LIB_ASHRDI3
278 select GENERIC_LIB_LSHRDI3
279 select GENERIC_LIB_UCMPDI2
285 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
286 select SWIOTLB if MMU
290 # We must be able to map all physical memory into the kernel, but the compiler
291 # is still a bit more efficient when generating code if it's setup in a manner
292 # such that it can only map 2GiB of memory.
294 prompt "Kernel Code Model"
295 default CMODEL_MEDLOW if 32BIT
296 default CMODEL_MEDANY if 64BIT
299 bool "medium low code model"
301 bool "medium any code model"
304 config MODULE_SECTIONS
306 select HAVE_MOD_ARCH_SPECIFIC
309 bool "Symmetric Multi-Processing"
311 This enables support for systems with more than one CPU. If
312 you say N here, the kernel will run on single and
313 multiprocessor machines, but will use only one CPU of a
314 multiprocessor machine. If you say Y here, the kernel will run
315 on many, but not all, single processor machines. On a single
316 processor machine, the kernel will run faster if you say N
319 If you don't know what to do here, say N.
322 int "Maximum number of CPUs (2-512)"
324 range 2 512 if !RISCV_SBI_V01
325 range 2 32 if RISCV_SBI_V01 && 32BIT
326 range 2 64 if RISCV_SBI_V01 && 64BIT
327 default "32" if 32BIT
328 default "64" if 64BIT
331 bool "Support for hot-pluggable CPUs"
333 select GENERIC_IRQ_MIGRATION
336 Say Y here to experiment with turning CPUs off and on. CPUs
337 can be controlled through /sys/devices/system/cpu.
339 Say N if you want to disable CPU hotplug.
350 # Common NUMA Features
352 bool "NUMA Memory Allocation and Scheduler Support"
353 depends on SMP && MMU
354 select GENERIC_ARCH_NUMA
356 select ARCH_SUPPORTS_NUMA_BALANCING
357 select USE_PERCPU_NUMA_NODE_ID
358 select NEED_PER_CPU_EMBED_FIRST_CHUNK
360 Enable NUMA (Non-Uniform Memory Access) support.
362 The kernel will try to allocate memory used by a CPU on the
363 local memory of the CPU and add some more NUMA awareness to the kernel.
366 int "Maximum NUMA Nodes (as a power of 2)"
371 Specify the maximum number of NUMA Nodes available on the target
372 system. Increases memory reserved to accommodate various tables.
374 config RISCV_ALTERNATIVE
376 depends on !XIP_KERNEL
378 This Kconfig allows the kernel to automatically patch the
379 errata required by the execution platform at run time. The
380 code patching is performed once in the boot stages. It means
381 that the overhead from this mechanism is just taken once.
383 config RISCV_ALTERNATIVE_EARLY
385 depends on RISCV_ALTERNATIVE
387 Allows early patching of the kernel for special errata
390 bool "Emit compressed instructions when building Linux"
393 Adds "C" to the ISA subsets that the toolchain is allowed to emit
394 when building Linux, which results in compressed instructions in the
397 If you don't know what to do here, say Y.
399 config RISCV_ISA_SVPBMT
400 bool "SVPBMT extension support"
401 depends on 64BIT && MMU
402 depends on !XIP_KERNEL
403 select RISCV_ALTERNATIVE
406 Adds support to dynamically detect the presence of the SVPBMT
407 ISA-extension (Supervisor-mode: page-based memory types) and
410 The memory type for a page contains a combination of attributes
411 that indicate the cacheability, idempotency, and ordering
412 properties for access to that page.
414 The SVPBMT extension is only available on 64Bit cpus.
416 If you don't know what to do here, say Y.
418 config TOOLCHAIN_HAS_ZICBOM
421 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicbom)
422 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom)
423 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23800
425 config RISCV_ISA_ZICBOM
426 bool "Zicbom extension support for non-coherent DMA operation"
427 depends on TOOLCHAIN_HAS_ZICBOM
428 depends on !XIP_KERNEL && MMU
429 select RISCV_DMA_NONCOHERENT
430 select RISCV_ALTERNATIVE
433 Adds support to dynamically detect the presence of the ZICBOM
434 extension (Cache Block Management Operations) and enable its
437 The Zicbom extension can be used to handle for example
438 non-coherent DMA support on devices that need it.
440 If you don't know what to do here, say Y.
442 config TOOLCHAIN_HAS_ZIHINTPAUSE
445 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause)
446 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause)
447 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600
453 Say N here if you want to disable all floating-point related procedure
456 If you don't know what to do here, say Y.
458 endmenu # "Platform type"
460 menu "Kernel features"
462 source "kernel/Kconfig.hz"
465 bool "SBI v0.1 support"
468 This config allows kernel to use SBI v0.1 APIs. This will be
469 deprecated in future once legacy M-mode software are no longer in use.
471 config RISCV_BOOT_SPINWAIT
472 bool "Spinwait booting method"
474 default y if RISCV_SBI_V01 || RISCV_M_MODE
476 This enables support for booting Linux via spinwait method. In the
477 spinwait method, all cores randomly jump to Linux. One of the cores
478 gets chosen via lottery and all other keep spinning on a percpu
479 variable. This method cannot support CPU hotplug and sparse hartid
480 scheme. It should be only enabled for M-mode Linux or platforms relying
481 on older firmware without SBI HSM extension. All other platforms should
482 rely on ordered booting via SBI HSM extension which gets chosen
483 dynamically at runtime if the firmware supports it.
485 Since spinwait is incompatible with sparse hart IDs, it requires
486 NR_CPUS be large enough to contain the physical hart ID of the first
489 If unsure what to do here, say N.
492 bool "Kexec system call"
494 select HOTPLUG_CPU if SMP
497 kexec is a system call that implements the ability to shutdown your
498 current kernel, and to start another kernel. It is like a reboot
499 but it is independent of the system firmware. And like a reboot
500 you can start any kernel with it, not just Linux.
502 The name comes from the similarity to the exec system call.
505 bool "kexec file based systmem call"
508 select HAVE_IMA_KEXEC if IMA
509 depends on 64BIT && MMU
511 This is new version of kexec system call. This system call is
512 file based and takes file descriptors as system call argument
513 for kernel and initramfs as opposed to list of segments as
514 accepted by previous system call.
516 If you don't know what to do here, say Y.
518 config ARCH_HAS_KEXEC_PURGATORY
521 depends on CRYPTO_SHA256=y
524 bool "Build kdump crash kernel"
526 Generate crash dump after being started by kexec. This should
527 be normally only set in special crash dump kernels which are
528 loaded in the main kernel with kexec-tools into a specially
529 reserved region and then later executed after a crash by
532 For more details see Documentation/admin-guide/kdump/kdump.rst
535 bool "Kernel support for 32-bit U-mode"
537 depends on 64BIT && MMU
539 This option enables support for a 32-bit U-mode running under a 64-bit
540 kernel at S-mode. riscv32-specific components such as system calls,
541 the user helper functions (vdso), signal rt_frame functions and the
542 ptrace interface are handled appropriately by the kernel.
544 If you want to execute 32-bit userspace applications, say Y.
546 endmenu # "Kernel features"
551 string "Built-in kernel command line"
553 For most platforms, the arguments for the kernel's command line
554 are provided at run-time, during boot. However, there are cases
555 where either no arguments are being provided or the provided
556 arguments are insufficient or even invalid.
558 When that occurs, it is possible to define a built-in command
559 line here and choose how the kernel should use it later on.
562 prompt "Built-in command line usage" if CMDLINE != ""
563 default CMDLINE_FALLBACK
565 Choose how the kernel will handle the provided built-in command
568 config CMDLINE_FALLBACK
569 bool "Use bootloader kernel arguments if available"
571 Use the built-in command line as fallback in case we get nothing
572 during boot. This is the default behaviour.
574 config CMDLINE_EXTEND
575 bool "Extend bootloader kernel arguments"
577 The command-line arguments provided during boot will be
578 appended to the built-in command line. This is useful in
579 cases where the provided arguments are insufficient and
580 you don't want to or cannot modify them.
583 bool "Always use the default kernel command string"
585 Always use the built-in command line, even if we get one during
586 boot. This is useful in case you need to override the provided
587 command line on systems where you don't have or want control
596 bool "UEFI runtime support"
597 depends on OF && !XIP_KERNEL
600 select EFI_PARAMS_FROM_FDT
602 select EFI_GENERIC_STUB
603 select EFI_RUNTIME_WRAPPERS
608 This option provides support for runtime services provided
609 by UEFI firmware (such as non-volatile variables, realtime
610 clock, and platform reset). A UEFI stub is also provided to
611 allow the kernel to be booted as an EFI application. This
612 is only useful on systems that have UEFI firmware.
614 config CC_HAVE_STACKPROTECTOR_TLS
615 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
617 config STACKPROTECTOR_PER_TASK
619 depends on !RANDSTRUCT
620 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
622 config PHYS_RAM_BASE_FIXED
623 bool "Explicitly specified physical RAM address"
624 depends on NONPORTABLE
628 hex "Platform Physical RAM address"
629 depends on PHYS_RAM_BASE_FIXED
632 This is the physical address of RAM in the system. It has to be
633 explicitly specified to run early relocations of read-write data
637 bool "Kernel Execute-In-Place from ROM"
638 depends on MMU && SPARSEMEM && NONPORTABLE
639 # This prevents XIP from being enabled by all{yes,mod}config, which
640 # fail to build since XIP doesn't support large kernels.
641 depends on !COMPILE_TEST
642 select PHYS_RAM_BASE_FIXED
644 Execute-In-Place allows the kernel to run from non-volatile storage
645 directly addressable by the CPU, such as NOR flash. This saves RAM
646 space since the text section of the kernel is not loaded from flash
647 to RAM. Read-write sections, such as the data section and stack,
648 are still copied to RAM. The XIP kernel is not compressed since
649 it has to run directly from flash, so it will take more space to
650 store it. The flash address used to link the kernel object files,
651 and for storing it, is configuration dependent. Therefore, if you
652 say Y here, you must know the proper physical address where to
653 store the kernel image depending on your own flash memory usage.
655 Also note that the make target becomes "make xipImage" rather than
656 "make zImage" or "make Image". The final kernel binary to put in
657 ROM memory will be arch/riscv/boot/xipImage.
659 SPARSEMEM is required because the kernel text and rodata that are
660 flash resident are not backed by memmap, then any attempt to get
661 a struct page on those regions will trigger a fault.
666 hex "XIP Kernel Physical Location"
667 depends on XIP_KERNEL
670 This is the physical address in your flash memory the kernel will
671 be linked for and stored to. This address is dependent on your
674 endmenu # "Boot options"
678 depends on OF && NONPORTABLE
679 default y if XIP_KERNEL
688 menu "Power management options"
690 source "kernel/power/Kconfig"
692 endmenu # "Power management options"
694 menu "CPU Power Management"
696 source "drivers/cpuidle/Kconfig"
698 source "drivers/cpufreq/Kconfig"
700 endmenu # "CPU Power Management"
702 source "arch/riscv/kvm/Kconfig"