xref: /linux/arch/riscv/Kconfig (revision 38acdee32d23f789e866488c99867fd497d43c86)
1# SPDX-License-Identifier: GPL-2.0-only
2#
3# For a description of the syntax of this configuration file,
4# see Documentation/kbuild/kconfig-language.rst.
5#
6
7config 64BIT
8	bool
9
10config 32BIT
11	bool
12
13config RISCV
14	def_bool y
15	select ACPI_GENERIC_GSI if ACPI
16	select ACPI_MCFG if (ACPI && PCI)
17	select ACPI_PPTT if ACPI
18	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
19	select ACPI_SPCR_TABLE if ACPI
20	select ARCH_DMA_DEFAULT_COHERENT
21	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
22	select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM_VMEMMAP
23	select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
24	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
25	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
26	select ARCH_HAS_BINFMT_FLAT
27	select ARCH_HAS_CURRENT_STACK_POINTER
28	select ARCH_HAS_DEBUG_VIRTUAL if MMU
29	select ARCH_HAS_DEBUG_VM_PGTABLE
30	select ARCH_HAS_DEBUG_WX
31	select ARCH_HAS_FAST_MULTIPLIER
32	select ARCH_HAS_FORTIFY_SOURCE
33	select ARCH_HAS_GCOV_PROFILE_ALL
34	select ARCH_HAS_GIGANTIC_PAGE
35	select ARCH_HAS_KCOV
36	select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU
37	select ARCH_HAS_MEMBARRIER_CALLBACKS
38	select ARCH_HAS_MEMBARRIER_SYNC_CORE
39	select ARCH_HAS_MMIOWB
40	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
41	select ARCH_HAS_PMEM_API
42	select ARCH_HAS_PREPARE_SYNC_CORE_CMD
43	select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU
44	select ARCH_HAS_PTE_SPECIAL
45	select ARCH_HAS_SET_DIRECT_MAP if MMU
46	select ARCH_HAS_SET_MEMORY if MMU
47	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
48	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
49	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
50	select ARCH_HAS_SYSCALL_WRAPPER
51	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
52	select ARCH_HAS_UBSAN
53	select ARCH_HAS_VDSO_DATA
54	select ARCH_KEEP_MEMBLOCK if ACPI
55	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
56	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
57	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
58	select ARCH_STACKWALK
59	select ARCH_SUPPORTS_ATOMIC_RMW
60	select ARCH_SUPPORTS_CFI_CLANG
61	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
62	select ARCH_SUPPORTS_HUGETLBFS if MMU
63	# LLD >= 14: https://github.com/llvm/llvm-project/issues/50505
64	select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000
65	select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000
66	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
67	select ARCH_SUPPORTS_PER_VMA_LOCK if MMU
68	select ARCH_SUPPORTS_RT
69	select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK
70	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
71	select ARCH_USE_MEMTEST
72	select ARCH_USE_QUEUED_RWLOCKS
73	select ARCH_USE_SYM_ANNOTATIONS
74	select ARCH_USES_CFI_TRAPS if CFI_CLANG
75	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
76	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
77	select ARCH_WANT_FRAME_POINTERS
78	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
79	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
80	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
81	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
82	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
83	select ARCH_WANTS_NO_INSTR
84	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
85	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
86	select BUILDTIME_TABLE_SORT if MMU
87	select CLINT_TIMER if RISCV_M_MODE
88	select CLONE_BACKWARDS
89	select COMMON_CLK
90	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
91	select EDAC_SUPPORT
92	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
93	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
94	select GENERIC_ARCH_TOPOLOGY
95	select GENERIC_ATOMIC64 if !64BIT
96	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
97	select GENERIC_CPU_DEVICES
98	select GENERIC_CPU_VULNERABILITIES
99	select GENERIC_EARLY_IOREMAP
100	select GENERIC_ENTRY
101	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
102	select GENERIC_IDLE_POLL_SETUP
103	select GENERIC_IOREMAP if MMU
104	select GENERIC_IRQ_IPI if SMP
105	select GENERIC_IRQ_IPI_MUX if SMP
106	select GENERIC_IRQ_MULTI_HANDLER
107	select GENERIC_IRQ_SHOW
108	select GENERIC_IRQ_SHOW_LEVEL
109	select GENERIC_LIB_DEVMEM_IS_ALLOWED
110	select GENERIC_PCI_IOMAP
111	select GENERIC_PTDUMP if MMU
112	select GENERIC_SCHED_CLOCK
113	select GENERIC_SMP_IDLE_THREAD
114	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
115	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
116	select HARDIRQS_SW_RESEND
117	select HAS_IOPORT if MMU
118	select HAVE_ARCH_AUDITSYSCALL
119	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
120	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT
121	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
122	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
123	select HAVE_ARCH_KASAN if MMU && 64BIT
124	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
125	select HAVE_ARCH_KFENCE if MMU && 64BIT
126	select HAVE_ARCH_KGDB if !XIP_KERNEL
127	select HAVE_ARCH_KGDB_QXFER_PKT
128	select HAVE_ARCH_MMAP_RND_BITS if MMU
129	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
130	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
131	select HAVE_ARCH_SECCOMP_FILTER
132	select HAVE_ARCH_STACKLEAK
133	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
134	select HAVE_ARCH_TRACEHOOK
135	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
136	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
137	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
138	select HAVE_ASM_MODVERSIONS
139	select HAVE_CONTEXT_TRACKING_USER
140	select HAVE_DEBUG_KMEMLEAK
141	select HAVE_DMA_CONTIGUOUS if MMU
142	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE)
143	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
144	select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
145	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
146	select HAVE_FUNCTION_GRAPH_TRACER
147	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
148	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
149	select HAVE_EBPF_JIT if MMU
150	select HAVE_GUP_FAST if MMU
151	select HAVE_FUNCTION_ARG_ACCESS_API
152	select HAVE_FUNCTION_ERROR_INJECTION
153	select HAVE_GCC_PLUGINS
154	select HAVE_GENERIC_VDSO if MMU && 64BIT
155	select HAVE_IRQ_TIME_ACCOUNTING
156	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
157	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
158	select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT
159	select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT
160	select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT
161	select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT
162	select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT
163	select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT
164	select HAVE_KPROBES if !XIP_KERNEL
165	select HAVE_KRETPROBES if !XIP_KERNEL
166	# https://github.com/ClangBuiltLinux/linux/issues/1881
167	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
168	select HAVE_MOVE_PMD
169	select HAVE_MOVE_PUD
170	select HAVE_PAGE_SIZE_4KB
171	select HAVE_PCI
172	select HAVE_PERF_EVENTS
173	select HAVE_PERF_REGS
174	select HAVE_PERF_USER_STACK_DUMP
175	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
176	select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL
177	select HAVE_REGS_AND_STACK_ACCESS_API
178	select HAVE_RETHOOK if !XIP_KERNEL
179	select HAVE_RSEQ
180	select HAVE_RUST if RUSTC_SUPPORTS_RISCV
181	select HAVE_SAMPLE_FTRACE_DIRECT
182	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
183	select HAVE_STACKPROTECTOR
184	select HAVE_SYSCALL_TRACEPOINTS
185	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
186	select IRQ_DOMAIN
187	select IRQ_FORCED_THREADING
188	select KASAN_VMALLOC if KASAN
189	select LOCK_MM_AND_FIND_VMA
190	select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU
191	select MODULES_USE_ELF_RELA if MODULES
192	select OF
193	select OF_EARLY_FLATTREE
194	select OF_IRQ
195	select PCI_DOMAINS_GENERIC if PCI
196	select PCI_ECAM if (ACPI && PCI)
197	select PCI_MSI if PCI
198	select RISCV_ALTERNATIVE if !XIP_KERNEL
199	select RISCV_APLIC
200	select RISCV_IMSIC
201	select RISCV_INTC
202	select RISCV_TIMER if RISCV_SBI
203	select SIFIVE_PLIC
204	select SPARSE_IRQ
205	select SYSCTL_EXCEPTION_TRACE
206	select THREAD_INFO_IN_TASK
207	select TRACE_IRQFLAGS_SUPPORT
208	select UACCESS_MEMCPY if !MMU
209	select USER_STACKTRACE_SUPPORT
210	select ZONE_DMA32 if 64BIT
211
212config RUSTC_SUPPORTS_RISCV
213	def_bool y
214	depends on 64BIT
215	# Shadow call stack requires rustc version 1.82+ due to use of the
216	# -Zsanitizer=shadow-call-stack flag.
217	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
218
219config CLANG_SUPPORTS_DYNAMIC_FTRACE
220	def_bool CC_IS_CLANG
221	# https://github.com/ClangBuiltLinux/linux/issues/1817
222	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
223
224config GCC_SUPPORTS_DYNAMIC_FTRACE
225	def_bool CC_IS_GCC
226	depends on $(cc-option,-fpatchable-function-entry=8)
227
228config HAVE_SHADOW_CALL_STACK
229	def_bool $(cc-option,-fsanitize=shadow-call-stack)
230	# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
231	depends on $(ld-option,--no-relax-gp)
232
233config RISCV_USE_LINKER_RELAXATION
234	def_bool y
235	# https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
236	depends on !LD_IS_LLD || LLD_VERSION >= 150000
237
238# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6
239config ARCH_HAS_BROKEN_DWARF5
240	def_bool y
241	depends on RISCV_USE_LINKER_RELAXATION
242	# https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a
243	depends on AS_IS_LLVM && AS_VERSION < 180000
244	# https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77
245	depends on LD_IS_LLD && LLD_VERSION < 180000
246
247config ARCH_MMAP_RND_BITS_MIN
248	default 18 if 64BIT
249	default 8
250
251config ARCH_MMAP_RND_COMPAT_BITS_MIN
252	default 8
253
254# max bits determined by the following formula:
255#  VA_BITS - PAGE_SHIFT - 3
256config ARCH_MMAP_RND_BITS_MAX
257	default 24 if 64BIT # SV39 based
258	default 17
259
260config ARCH_MMAP_RND_COMPAT_BITS_MAX
261	default 17
262
263# set if we run in machine mode, cleared if we run in supervisor mode
264config RISCV_M_MODE
265	bool "Build a kernel that runs in machine mode"
266	depends on !MMU
267	default y
268	help
269	  Select this option if you want to run the kernel in M-mode,
270	  without the assistance of any other firmware.
271
272# set if we are running in S-mode and can use SBI calls
273config RISCV_SBI
274	bool
275	depends on !RISCV_M_MODE
276	default y
277
278config MMU
279	bool "MMU-based Paged Memory Management Support"
280	default y
281	help
282	  Select if you want MMU-based virtualised addressing space
283	  support by paged memory management. If unsure, say 'Y'.
284
285config PAGE_OFFSET
286	hex
287	default 0x80000000 if !MMU && RISCV_M_MODE
288	default 0x80200000 if !MMU
289	default 0xc0000000 if 32BIT
290	default 0xff60000000000000 if 64BIT
291
292config KASAN_SHADOW_OFFSET
293	hex
294	depends on KASAN_GENERIC
295	default 0xdfffffff00000000 if 64BIT
296	default 0xffffffff if 32BIT
297
298config ARCH_FLATMEM_ENABLE
299	def_bool !NUMA
300
301config ARCH_SPARSEMEM_ENABLE
302	def_bool y
303	depends on MMU
304	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
305	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
306
307config ARCH_SELECT_MEMORY_MODEL
308	def_bool ARCH_SPARSEMEM_ENABLE
309
310config ARCH_SUPPORTS_UPROBES
311	def_bool y
312
313config STACKTRACE_SUPPORT
314	def_bool y
315
316config GENERIC_BUG
317	def_bool y
318	depends on BUG
319	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
320
321config GENERIC_BUG_RELATIVE_POINTERS
322	bool
323
324config GENERIC_CALIBRATE_DELAY
325	def_bool y
326
327config GENERIC_CSUM
328	def_bool y
329
330config GENERIC_HWEIGHT
331	def_bool y
332
333config FIX_EARLYCON_MEM
334	def_bool MMU
335
336config ILLEGAL_POINTER_VALUE
337	hex
338	default 0 if 32BIT
339	default 0xdead000000000000 if 64BIT
340
341config PGTABLE_LEVELS
342	int
343	default 5 if 64BIT
344	default 2
345
346config LOCKDEP_SUPPORT
347	def_bool y
348
349config RISCV_DMA_NONCOHERENT
350	bool
351	select ARCH_HAS_DMA_PREP_COHERENT
352	select ARCH_HAS_SETUP_DMA_OPS
353	select ARCH_HAS_SYNC_DMA_FOR_CPU
354	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
355	select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB
356
357config RISCV_NONSTANDARD_CACHE_OPS
358	bool
359	help
360	  This enables function pointer support for non-standard noncoherent
361	  systems to handle cache management.
362
363config AS_HAS_INSN
364	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
365
366config AS_HAS_OPTION_ARCH
367	# https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
368	def_bool y
369	depends on $(as-instr, .option arch$(comma) +m)
370
371source "arch/riscv/Kconfig.socs"
372source "arch/riscv/Kconfig.errata"
373
374menu "Platform type"
375
376config NONPORTABLE
377	bool "Allow configurations that result in non-portable kernels"
378	help
379	  RISC-V kernel binaries are compatible between all known systems
380	  whenever possible, but there are some use cases that can only be
381	  satisfied by configurations that result in kernel binaries that are
382	  not portable between systems.
383
384	  Selecting N does not guarantee kernels will be portable to all known
385	  systems.  Selecting any of the options guarded by NONPORTABLE will
386	  result in kernel binaries that are unlikely to be portable between
387	  systems.
388
389	  If unsure, say N.
390
391choice
392	prompt "Base ISA"
393	default ARCH_RV64I
394	help
395	  This selects the base ISA that this kernel will target and must match
396	  the target platform.
397
398config ARCH_RV32I
399	bool "RV32I"
400	depends on NONPORTABLE
401	select 32BIT
402	select GENERIC_LIB_ASHLDI3
403	select GENERIC_LIB_ASHRDI3
404	select GENERIC_LIB_LSHRDI3
405	select GENERIC_LIB_UCMPDI2
406
407config ARCH_RV64I
408	bool "RV64I"
409	select 64BIT
410	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
411	select SWIOTLB if MMU
412
413endchoice
414
415# We must be able to map all physical memory into the kernel, but the compiler
416# is still a bit more efficient when generating code if it's setup in a manner
417# such that it can only map 2GiB of memory.
418choice
419	prompt "Kernel Code Model"
420	default CMODEL_MEDLOW if 32BIT
421	default CMODEL_MEDANY if 64BIT
422
423	config CMODEL_MEDLOW
424		bool "medium low code model"
425	config CMODEL_MEDANY
426		bool "medium any code model"
427endchoice
428
429config MODULE_SECTIONS
430	bool
431	select HAVE_MOD_ARCH_SPECIFIC
432
433config SMP
434	bool "Symmetric Multi-Processing"
435	help
436	  This enables support for systems with more than one CPU.  If
437	  you say N here, the kernel will run on single and
438	  multiprocessor machines, but will use only one CPU of a
439	  multiprocessor machine. If you say Y here, the kernel will run
440	  on many, but not all, single processor machines. On a single
441	  processor machine, the kernel will run faster if you say N
442	  here.
443
444	  If you don't know what to do here, say N.
445
446config SCHED_MC
447	bool "Multi-core scheduler support"
448	depends on SMP
449	help
450	  Multi-core scheduler support improves the CPU scheduler's decision
451	  making when dealing with multi-core CPU chips at a cost of slightly
452	  increased overhead in some places. If unsure say N here.
453
454config NR_CPUS
455	int "Maximum number of CPUs (2-512)"
456	depends on SMP
457	range 2 512 if !RISCV_SBI_V01
458	range 2 32 if RISCV_SBI_V01 && 32BIT
459	range 2 64 if RISCV_SBI_V01 && 64BIT
460	default "32" if 32BIT
461	default "64" if 64BIT
462
463config HOTPLUG_CPU
464	bool "Support for hot-pluggable CPUs"
465	depends on SMP
466	select GENERIC_IRQ_MIGRATION
467	help
468
469	  Say Y here to experiment with turning CPUs off and on.  CPUs
470	  can be controlled through /sys/devices/system/cpu.
471
472	  Say N if you want to disable CPU hotplug.
473
474choice
475	prompt "CPU Tuning"
476	default TUNE_GENERIC
477
478config TUNE_GENERIC
479	bool "generic"
480
481endchoice
482
483# Common NUMA Features
484config NUMA
485	bool "NUMA Memory Allocation and Scheduler Support"
486	depends on SMP && MMU
487	select ARCH_SUPPORTS_NUMA_BALANCING
488	select GENERIC_ARCH_NUMA
489	select HAVE_SETUP_PER_CPU_AREA
490	select NEED_PER_CPU_EMBED_FIRST_CHUNK
491	select NEED_PER_CPU_PAGE_FIRST_CHUNK
492	select OF_NUMA
493	select USE_PERCPU_NUMA_NODE_ID
494	help
495	  Enable NUMA (Non-Uniform Memory Access) support.
496
497	  The kernel will try to allocate memory used by a CPU on the
498	  local memory of the CPU and add some more NUMA awareness to the kernel.
499
500config NODES_SHIFT
501	int "Maximum NUMA Nodes (as a power of 2)"
502	range 1 10
503	default "2"
504	depends on NUMA
505	help
506	  Specify the maximum number of NUMA Nodes available on the target
507	  system.  Increases memory reserved to accommodate various tables.
508
509config RISCV_ALTERNATIVE
510	bool
511	depends on !XIP_KERNEL
512	help
513	  This Kconfig allows the kernel to automatically patch the
514	  erratum or cpufeature required by the execution platform at run
515	  time. The code patching overhead is minimal, as it's only done
516	  once at boot and once on each module load.
517
518config RISCV_ALTERNATIVE_EARLY
519	bool
520	depends on RISCV_ALTERNATIVE
521	help
522	  Allows early patching of the kernel for special errata
523
524config RISCV_ISA_C
525	bool "Emit compressed instructions when building Linux"
526	default y
527	help
528	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
529	  when building Linux, which results in compressed instructions in the
530	  Linux binary.
531
532	  If you don't know what to do here, say Y.
533
534config RISCV_ISA_SVNAPOT
535	bool "Svnapot extension support for supervisor mode NAPOT pages"
536	depends on 64BIT && MMU
537	depends on RISCV_ALTERNATIVE
538	default y
539	help
540	  Allow kernel to detect the Svnapot ISA-extension dynamically at boot
541	  time and enable its usage.
542
543	  The Svnapot extension is used to mark contiguous PTEs as a range
544	  of contiguous virtual-to-physical translations for a naturally
545	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
546	  size. When HUGETLBFS is also selected this option unconditionally
547	  allocates some memory for each NAPOT page size supported by the kernel.
548	  When optimizing for low memory consumption and for platforms without
549	  the Svnapot extension, it may be better to say N here.
550
551	  If you don't know what to do here, say Y.
552
553config RISCV_ISA_SVPBMT
554	bool "Svpbmt extension support for supervisor mode page-based memory types"
555	depends on 64BIT && MMU
556	depends on RISCV_ALTERNATIVE
557	default y
558	help
559	   Adds support to dynamically detect the presence of the Svpbmt
560	   ISA-extension (Supervisor-mode: page-based memory types) and
561	   enable its usage.
562
563	   The memory type for a page contains a combination of attributes
564	   that indicate the cacheability, idempotency, and ordering
565	   properties for access to that page.
566
567	   The Svpbmt extension is only available on 64-bit cpus.
568
569	   If you don't know what to do here, say Y.
570
571config TOOLCHAIN_HAS_V
572	bool
573	default y
574	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv)
575	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv)
576	depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800
577	depends on AS_HAS_OPTION_ARCH
578
579config RISCV_ISA_V
580	bool "VECTOR extension support"
581	depends on TOOLCHAIN_HAS_V
582	depends on FPU
583	select DYNAMIC_SIGFRAME
584	default y
585	help
586	  Say N here if you want to disable all vector related procedure
587	  in the kernel.
588
589	  If you don't know what to do here, say Y.
590
591config RISCV_ISA_V_DEFAULT_ENABLE
592	bool "Enable userspace Vector by default"
593	depends on RISCV_ISA_V
594	default y
595	help
596	  Say Y here if you want to enable Vector in userspace by default.
597	  Otherwise, userspace has to make explicit prctl() call to enable
598	  Vector, or enable it via the sysctl interface.
599
600	  If you don't know what to do here, say Y.
601
602config RISCV_ISA_V_UCOPY_THRESHOLD
603	int "Threshold size for vectorized user copies"
604	depends on RISCV_ISA_V
605	default 768
606	help
607	  Prefer using vectorized copy_to_user()/copy_from_user() when the
608	  workload size exceeds this value.
609
610config RISCV_ISA_V_PREEMPTIVE
611	bool "Run kernel-mode Vector with kernel preemption"
612	depends on PREEMPTION
613	depends on RISCV_ISA_V
614	default y
615	help
616	  Usually, in-kernel SIMD routines are run with preemption disabled.
617	  Functions which envoke long running SIMD thus must yield core's
618	  vector unit to prevent blocking other tasks for too long.
619
620	  This config allows kernel to run SIMD without explicitly disable
621	  preemption. Enabling this config will result in higher memory
622	  consumption due to the allocation of per-task's kernel Vector context.
623
624config RISCV_ISA_ZAWRS
625	bool "Zawrs extension support for more efficient busy waiting"
626	depends on RISCV_ALTERNATIVE
627	default y
628	help
629	  The Zawrs extension defines instructions to be used in polling loops
630	  which allow a hart to enter a low-power state or to trap to the
631	  hypervisor while waiting on a store to a memory location. Enable the
632	  use of these instructions in the kernel when the Zawrs extension is
633	  detected at boot.
634
635config TOOLCHAIN_HAS_ZACAS
636	bool
637	default y
638	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas)
639	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas)
640	depends on AS_HAS_OPTION_ARCH
641
642config RISCV_ISA_ZACAS
643	bool "Zacas extension support for atomic CAS"
644	depends on TOOLCHAIN_HAS_ZACAS
645	depends on RISCV_ALTERNATIVE
646	default y
647	help
648	  Enable the use of the Zacas ISA-extension to implement kernel atomic
649	  cmpxchg operations when it is detected at boot.
650
651	  If you don't know what to do here, say Y.
652
653config TOOLCHAIN_HAS_ZBB
654	bool
655	default y
656	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
657	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
658	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
659	depends on AS_HAS_OPTION_ARCH
660
661# This symbol indicates that the toolchain supports all v1.0 vector crypto
662# extensions, including Zvk*, Zvbb, and Zvbc.  LLVM added all of these at once.
663# binutils added all except Zvkb, then added Zvkb.  So we just check for Zvkb.
664config TOOLCHAIN_HAS_VECTOR_CRYPTO
665	def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb)
666	depends on AS_HAS_OPTION_ARCH
667
668config RISCV_ISA_ZBA
669	bool "Zba extension support for bit manipulation instructions"
670	default y
671	help
672	   Add support for enabling optimisations in the kernel when the Zba
673	   extension is detected at boot.
674
675	   The Zba extension provides instructions to accelerate the generation
676	   of addresses that index into arrays of basic data types.
677
678	   If you don't know what to do here, say Y.
679
680config RISCV_ISA_ZBB
681	bool "Zbb extension support for bit manipulation instructions"
682	depends on TOOLCHAIN_HAS_ZBB
683	depends on RISCV_ALTERNATIVE
684	default y
685	help
686	   Adds support to dynamically detect the presence of the ZBB
687	   extension (basic bit manipulation) and enable its usage.
688
689	   The Zbb extension provides instructions to accelerate a number
690	   of bit-specific operations (count bit population, sign extending,
691	   bitrotation, etc).
692
693	   If you don't know what to do here, say Y.
694
695config TOOLCHAIN_HAS_ZBC
696	bool
697	default y
698	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc)
699	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc)
700	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
701	depends on AS_HAS_OPTION_ARCH
702
703config RISCV_ISA_ZBC
704	bool "Zbc extension support for carry-less multiplication instructions"
705	depends on TOOLCHAIN_HAS_ZBC
706	depends on MMU
707	depends on RISCV_ALTERNATIVE
708	default y
709	help
710	   Adds support to dynamically detect the presence of the Zbc
711	   extension (carry-less multiplication) and enable its usage.
712
713	   The Zbc extension could accelerate CRC (cyclic redundancy check)
714	   calculations.
715
716	   If you don't know what to do here, say Y.
717
718config RISCV_ISA_ZICBOM
719	bool "Zicbom extension support for non-coherent DMA operation"
720	depends on MMU
721	depends on RISCV_ALTERNATIVE
722	default y
723	select RISCV_DMA_NONCOHERENT
724	select DMA_DIRECT_REMAP
725	help
726	   Adds support to dynamically detect the presence of the ZICBOM
727	   extension (Cache Block Management Operations) and enable its
728	   usage.
729
730	   The Zicbom extension can be used to handle for example
731	   non-coherent DMA support on devices that need it.
732
733	   If you don't know what to do here, say Y.
734
735config RISCV_ISA_ZICBOZ
736	bool "Zicboz extension support for faster zeroing of memory"
737	depends on RISCV_ALTERNATIVE
738	default y
739	help
740	   Enable the use of the Zicboz extension (cbo.zero instruction)
741	   when available.
742
743	   The Zicboz extension is used for faster zeroing of memory.
744
745	   If you don't know what to do here, say Y.
746
747config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
748	def_bool y
749	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
750	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
751	depends on AS_IS_GNU && AS_VERSION >= 23600
752	help
753	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
754	  20191213 version, which moves some instructions from the I extension to
755	  the Zicsr and Zifencei extensions. This requires explicitly specifying
756	  Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
757	  and Zifencei are supported in binutils from version 2.36 onwards.
758	  To make life easier, and avoid forcing toolchains that default to a
759	  newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
760	  For clang < 17 or GCC < 11.3.0, for which this is not possible or need
761	  special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
762
763config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
764	def_bool y
765	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
766	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
767	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671
768	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300)
769	help
770	  Certain versions of clang and GCC do not support zicsr and zifencei via
771	  -march. This option causes an older ISA spec compatible with these older
772	  versions of clang and GCC to be passed to GAS, which has the same result
773	  as passing zicsr and zifencei to -march.
774
775config FPU
776	bool "FPU support"
777	default y
778	help
779	  Say N here if you want to disable all floating-point related procedure
780	  in the kernel.
781
782	  If you don't know what to do here, say Y.
783
784config IRQ_STACKS
785	bool "Independent irq & softirq stacks" if EXPERT
786	default y
787	select HAVE_IRQ_EXIT_ON_IRQ_STACK
788	select HAVE_SOFTIRQ_ON_OWN_STACK
789	help
790	  Add independent irq & softirq stacks for percpu to prevent kernel stack
791	  overflows. We may save some memory footprint by disabling IRQ_STACKS.
792
793config THREAD_SIZE_ORDER
794	int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT
795	range 0 4
796	default 1 if 32BIT
797	default 2
798	help
799	  Specify the Pages of thread stack size (from 4KB to 64KB), which also
800	  affects irq stack size, which is equal to thread stack size.
801
802config RISCV_MISALIGNED
803	bool
804	select SYSCTL_ARCH_UNALIGN_ALLOW
805	help
806	  Embed support for emulating misaligned loads and stores.
807
808choice
809	prompt "Unaligned Accesses Support"
810	default RISCV_PROBE_UNALIGNED_ACCESS
811	help
812	  This determines the level of support for unaligned accesses. This
813	  information is used by the kernel to perform optimizations. It is also
814	  exposed to user space via the hwprobe syscall. The hardware will be
815	  probed at boot by default.
816
817config RISCV_PROBE_UNALIGNED_ACCESS
818	bool "Probe for hardware unaligned access support"
819	select RISCV_MISALIGNED
820	help
821	  During boot, the kernel will run a series of tests to determine the
822	  speed of unaligned accesses. This probing will dynamically determine
823	  the speed of unaligned accesses on the underlying system. If unaligned
824	  memory accesses trap into the kernel as they are not supported by the
825	  system, the kernel will emulate the unaligned accesses to preserve the
826	  UABI.
827
828config RISCV_EMULATED_UNALIGNED_ACCESS
829	bool "Emulate unaligned access where system support is missing"
830	select RISCV_MISALIGNED
831	help
832	  If unaligned memory accesses trap into the kernel as they are not
833	  supported by the system, the kernel will emulate the unaligned
834	  accesses to preserve the UABI. When the underlying system does support
835	  unaligned accesses, the unaligned accesses are assumed to be slow.
836
837config RISCV_SLOW_UNALIGNED_ACCESS
838	bool "Assume the system supports slow unaligned memory accesses"
839	depends on NONPORTABLE
840	help
841	  Assume that the system supports slow unaligned memory accesses. The
842	  kernel and userspace programs may not be able to run at all on systems
843	  that do not support unaligned memory accesses.
844
845config RISCV_EFFICIENT_UNALIGNED_ACCESS
846	bool "Assume the system supports fast unaligned memory accesses"
847	depends on NONPORTABLE
848	select DCACHE_WORD_ACCESS if MMU
849	select HAVE_EFFICIENT_UNALIGNED_ACCESS
850	help
851	  Assume that the system supports fast unaligned memory accesses. When
852	  enabled, this option improves the performance of the kernel on such
853	  systems. However, the kernel and userspace programs will run much more
854	  slowly, or will not be able to run at all, on systems that do not
855	  support efficient unaligned memory accesses.
856
857endchoice
858
859source "arch/riscv/Kconfig.vendor"
860
861endmenu # "Platform type"
862
863menu "Kernel features"
864
865source "kernel/Kconfig.hz"
866
867config RISCV_SBI_V01
868	bool "SBI v0.1 support"
869	depends on RISCV_SBI
870	help
871	  This config allows kernel to use SBI v0.1 APIs. This will be
872	  deprecated in future once legacy M-mode software are no longer in use.
873
874config RISCV_BOOT_SPINWAIT
875	bool "Spinwait booting method"
876	depends on SMP
877	default y if RISCV_SBI_V01 || RISCV_M_MODE
878	help
879	  This enables support for booting Linux via spinwait method. In the
880	  spinwait method, all cores randomly jump to Linux. One of the cores
881	  gets chosen via lottery and all other keep spinning on a percpu
882	  variable. This method cannot support CPU hotplug and sparse hartid
883	  scheme. It should be only enabled for M-mode Linux or platforms relying
884	  on older firmware without SBI HSM extension. All other platforms should
885	  rely on ordered booting via SBI HSM extension which gets chosen
886	  dynamically at runtime if the firmware supports it.
887
888	  Since spinwait is incompatible with sparse hart IDs, it requires
889	  NR_CPUS be large enough to contain the physical hart ID of the first
890	  hart to enter Linux.
891
892	  If unsure what to do here, say N.
893
894config ARCH_SUPPORTS_KEXEC
895	def_bool y
896
897config ARCH_SELECTS_KEXEC
898	def_bool y
899	depends on KEXEC
900	select HOTPLUG_CPU if SMP
901
902config ARCH_SUPPORTS_KEXEC_FILE
903	def_bool 64BIT
904
905config ARCH_SELECTS_KEXEC_FILE
906	def_bool y
907	depends on KEXEC_FILE
908	select HAVE_IMA_KEXEC if IMA
909	select KEXEC_ELF
910
911config ARCH_SUPPORTS_KEXEC_PURGATORY
912	def_bool ARCH_SUPPORTS_KEXEC_FILE
913
914config ARCH_SUPPORTS_CRASH_DUMP
915	def_bool y
916
917config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
918	def_bool CRASH_RESERVE
919
920config COMPAT
921	bool "Kernel support for 32-bit U-mode"
922	default 64BIT
923	depends on 64BIT && MMU
924	help
925	  This option enables support for a 32-bit U-mode running under a 64-bit
926	  kernel at S-mode. riscv32-specific components such as system calls,
927	  the user helper functions (vdso), signal rt_frame functions and the
928	  ptrace interface are handled appropriately by the kernel.
929
930	  If you want to execute 32-bit userspace applications, say Y.
931
932config PARAVIRT
933	bool "Enable paravirtualization code"
934	depends on RISCV_SBI
935	help
936	  This changes the kernel so it can modify itself when it is run
937	  under a hypervisor, potentially improving performance significantly
938	  over full virtualization.
939
940config PARAVIRT_TIME_ACCOUNTING
941	bool "Paravirtual steal time accounting"
942	depends on PARAVIRT
943	help
944	  Select this option to enable fine granularity task steal time
945	  accounting. Time spent executing other tasks in parallel with
946	  the current vCPU is discounted from the vCPU power. To account for
947	  that, there can be a small performance impact.
948
949	  If in doubt, say N here.
950
951config RELOCATABLE
952	bool "Build a relocatable kernel"
953	depends on MMU && 64BIT && !XIP_KERNEL
954	select MODULE_SECTIONS if MODULES
955	help
956          This builds a kernel as a Position Independent Executable (PIE),
957          which retains all relocation metadata required to relocate the
958          kernel binary at runtime to a different virtual address than the
959          address it was linked at.
960          Since RISCV uses the RELA relocation format, this requires a
961          relocation pass at runtime even if the kernel is loaded at the
962          same address it was linked at.
963
964          If unsure, say N.
965
966config RANDOMIZE_BASE
967        bool "Randomize the address of the kernel image"
968        select RELOCATABLE
969        depends on MMU && 64BIT && !XIP_KERNEL
970        help
971          Randomizes the virtual address at which the kernel image is
972          loaded, as a security feature that deters exploit attempts
973          relying on knowledge of the location of kernel internals.
974
975          It is the bootloader's job to provide entropy, by passing a
976          random u64 value in /chosen/kaslr-seed at kernel entry.
977
978          When booting via the UEFI stub, it will invoke the firmware's
979          EFI_RNG_PROTOCOL implementation (if available) to supply entropy
980          to the kernel proper. In addition, it will randomise the physical
981          location of the kernel Image as well.
982
983          If unsure, say N.
984
985endmenu # "Kernel features"
986
987menu "Boot options"
988
989config CMDLINE
990	string "Built-in kernel command line"
991	help
992	  For most platforms, the arguments for the kernel's command line
993	  are provided at run-time, during boot. However, there are cases
994	  where either no arguments are being provided or the provided
995	  arguments are insufficient or even invalid.
996
997	  When that occurs, it is possible to define a built-in command
998	  line here and choose how the kernel should use it later on.
999
1000choice
1001	prompt "Built-in command line usage"
1002	depends on CMDLINE != ""
1003	default CMDLINE_FALLBACK
1004	help
1005	  Choose how the kernel will handle the provided built-in command
1006	  line.
1007
1008config CMDLINE_FALLBACK
1009	bool "Use bootloader kernel arguments if available"
1010	help
1011	  Use the built-in command line as fallback in case we get nothing
1012	  during boot. This is the default behaviour.
1013
1014config CMDLINE_EXTEND
1015	bool "Extend bootloader kernel arguments"
1016	help
1017	  The command-line arguments provided during boot will be
1018	  appended to the built-in command line. This is useful in
1019	  cases where the provided arguments are insufficient and
1020	  you don't want to or cannot modify them.
1021
1022config CMDLINE_FORCE
1023	bool "Always use the default kernel command string"
1024	help
1025	  Always use the built-in command line, even if we get one during
1026	  boot. This is useful in case you need to override the provided
1027	  command line on systems where you don't have or want control
1028	  over it.
1029
1030endchoice
1031
1032config EFI_STUB
1033	bool
1034
1035config EFI
1036	bool "UEFI runtime support"
1037	depends on OF && !XIP_KERNEL
1038	depends on MMU
1039	default y
1040	select ARCH_SUPPORTS_ACPI if 64BIT
1041	select EFI_GENERIC_STUB
1042	select EFI_PARAMS_FROM_FDT
1043	select EFI_RUNTIME_WRAPPERS
1044	select EFI_STUB
1045	select LIBFDT
1046	select RISCV_ISA_C
1047	select UCS2_STRING
1048	help
1049	  This option provides support for runtime services provided
1050	  by UEFI firmware (such as non-volatile variables, realtime
1051	  clock, and platform reset). A UEFI stub is also provided to
1052	  allow the kernel to be booted as an EFI application. This
1053	  is only useful on systems that have UEFI firmware.
1054
1055config DMI
1056	bool "Enable support for SMBIOS (DMI) tables"
1057	depends on EFI
1058	default y
1059	help
1060	  This enables SMBIOS/DMI feature for systems.
1061
1062	  This option is only useful on systems that have UEFI firmware.
1063	  However, even with this option, the resultant kernel should
1064	  continue to boot on existing non-UEFI platforms.
1065
1066config CC_HAVE_STACKPROTECTOR_TLS
1067	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
1068
1069config STACKPROTECTOR_PER_TASK
1070	def_bool y
1071	depends on !RANDSTRUCT
1072	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
1073
1074config PHYS_RAM_BASE_FIXED
1075	bool "Explicitly specified physical RAM address"
1076	depends on NONPORTABLE
1077	default n
1078
1079config PHYS_RAM_BASE
1080	hex "Platform Physical RAM address"
1081	depends on PHYS_RAM_BASE_FIXED
1082	default "0x80000000"
1083	help
1084	  This is the physical address of RAM in the system. It has to be
1085	  explicitly specified to run early relocations of read-write data
1086	  from flash to RAM.
1087
1088config XIP_KERNEL
1089	bool "Kernel Execute-In-Place from ROM"
1090	depends on MMU && SPARSEMEM && NONPORTABLE
1091	# This prevents XIP from being enabled by all{yes,mod}config, which
1092	# fail to build since XIP doesn't support large kernels.
1093	depends on !COMPILE_TEST
1094	select PHYS_RAM_BASE_FIXED
1095	help
1096	  Execute-In-Place allows the kernel to run from non-volatile storage
1097	  directly addressable by the CPU, such as NOR flash. This saves RAM
1098	  space since the text section of the kernel is not loaded from flash
1099	  to RAM.  Read-write sections, such as the data section and stack,
1100	  are still copied to RAM.  The XIP kernel is not compressed since
1101	  it has to run directly from flash, so it will take more space to
1102	  store it.  The flash address used to link the kernel object files,
1103	  and for storing it, is configuration dependent. Therefore, if you
1104	  say Y here, you must know the proper physical address where to
1105	  store the kernel image depending on your own flash memory usage.
1106
1107	  Also note that the make target becomes "make xipImage" rather than
1108	  "make zImage" or "make Image".  The final kernel binary to put in
1109	  ROM memory will be arch/riscv/boot/xipImage.
1110
1111	  SPARSEMEM is required because the kernel text and rodata that are
1112	  flash resident are not backed by memmap, then any attempt to get
1113	  a struct page on those regions will trigger a fault.
1114
1115	  If unsure, say N.
1116
1117config XIP_PHYS_ADDR
1118	hex "XIP Kernel Physical Location"
1119	depends on XIP_KERNEL
1120	default "0x21000000"
1121	help
1122	  This is the physical address in your flash memory the kernel will
1123	  be linked for and stored to.  This address is dependent on your
1124	  own flash usage.
1125
1126config RISCV_ISA_FALLBACK
1127	bool "Permit falling back to parsing riscv,isa for extension support by default"
1128	default y
1129	help
1130	  Parsing the "riscv,isa" devicetree property has been deprecated and
1131	  replaced by a list of explicitly defined strings. For compatibility
1132	  with existing platforms, the kernel will fall back to parsing the
1133	  "riscv,isa" property if the replacements are not found.
1134
1135	  Selecting N here will result in a kernel that does not use the
1136	  fallback, unless the commandline "riscv_isa_fallback" parameter is
1137	  present.
1138
1139	  Please see the dt-binding, located at
1140	  Documentation/devicetree/bindings/riscv/extensions.yaml for details
1141	  on the replacement properties, "riscv,isa-base" and
1142	  "riscv,isa-extensions".
1143
1144config BUILTIN_DTB
1145	bool "Built-in device tree"
1146	depends on OF && NONPORTABLE
1147	help
1148	  Build a device tree into the Linux image.
1149	  This option should be selected if no bootloader is being used.
1150	  If unsure, say N.
1151
1152
1153config BUILTIN_DTB_SOURCE
1154	string "Built-in device tree source"
1155	depends on BUILTIN_DTB
1156	help
1157	  DTS file path (without suffix, relative to arch/riscv/boot/dts)
1158	  for the DTS file that will be used to produce the DTB linked into the
1159	  kernel.
1160
1161endmenu # "Boot options"
1162
1163config PORTABLE
1164	bool
1165	default !NONPORTABLE
1166	select EFI
1167	select MMU
1168	select OF
1169
1170config ARCH_PROC_KCORE_TEXT
1171	def_bool y
1172
1173menu "Power management options"
1174
1175source "kernel/power/Kconfig"
1176
1177config ARCH_HIBERNATION_POSSIBLE
1178	def_bool y
1179
1180config ARCH_HIBERNATION_HEADER
1181	def_bool HIBERNATION
1182
1183config ARCH_SUSPEND_POSSIBLE
1184	def_bool y
1185
1186endmenu # "Power management options"
1187
1188menu "CPU Power Management"
1189
1190source "drivers/cpuidle/Kconfig"
1191
1192source "drivers/cpufreq/Kconfig"
1193
1194endmenu # "CPU Power Management"
1195
1196source "arch/riscv/kvm/Kconfig"
1197
1198source "drivers/acpi/Kconfig"
1199