xref: /linux/arch/riscv/Kconfig (revision e3610441d1fb47b1f00e4c38bdf333176e824729)
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_HW_PTE_YOUNG
36	select ARCH_HAS_KCOV
37	select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU
38	select ARCH_HAS_MEMBARRIER_CALLBACKS
39	select ARCH_HAS_MEMBARRIER_SYNC_CORE
40	select ARCH_HAS_MMIOWB
41	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
42	select ARCH_HAS_PMEM_API
43	select ARCH_HAS_PREEMPT_LAZY
44	select ARCH_HAS_PREPARE_SYNC_CORE_CMD
45	select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU
46	select ARCH_HAS_PTE_SPECIAL
47	select ARCH_HAS_SET_DIRECT_MAP if MMU
48	select ARCH_HAS_SET_MEMORY if MMU
49	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
50	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
51	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
52	select ARCH_HAS_SYSCALL_WRAPPER
53	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
54	select ARCH_HAS_UBSAN
55	select ARCH_HAS_VDSO_TIME_DATA
56	select ARCH_KEEP_MEMBLOCK if ACPI
57	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
58	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
59	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
60	select ARCH_STACKWALK
61	select ARCH_SUPPORTS_ATOMIC_RMW
62	select ARCH_SUPPORTS_CFI_CLANG
63	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
64	select ARCH_SUPPORTS_HUGETLBFS if MMU
65	# LLD >= 14: https://github.com/llvm/llvm-project/issues/50505
66	select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000
67	select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000
68	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
69	select ARCH_SUPPORTS_PER_VMA_LOCK if MMU
70	select ARCH_SUPPORTS_RT
71	select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK
72	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
73	select ARCH_USE_MEMTEST
74	select ARCH_USE_QUEUED_RWLOCKS
75	select ARCH_USE_SYM_ANNOTATIONS
76	select ARCH_USES_CFI_TRAPS if CFI_CLANG
77	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
78	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
79	select ARCH_WANT_FRAME_POINTERS
80	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
81	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
82	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
83	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
84	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
85	select ARCH_WANTS_NO_INSTR
86	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
87	select ARCH_WEAK_RELEASE_ACQUIRE if ARCH_USE_QUEUED_SPINLOCKS
88	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
89	select BUILDTIME_TABLE_SORT if MMU
90	select CLINT_TIMER if RISCV_M_MODE
91	select CLONE_BACKWARDS
92	select COMMON_CLK
93	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
94	select EDAC_SUPPORT
95	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
96	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
97	select GENERIC_ARCH_TOPOLOGY
98	select GENERIC_ATOMIC64 if !64BIT
99	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
100	select GENERIC_CPU_DEVICES
101	select GENERIC_CPU_VULNERABILITIES
102	select GENERIC_EARLY_IOREMAP
103	select GENERIC_ENTRY
104	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
105	select GENERIC_IDLE_POLL_SETUP
106	select GENERIC_IOREMAP if MMU
107	select GENERIC_IRQ_IPI if SMP
108	select GENERIC_IRQ_IPI_MUX if SMP
109	select GENERIC_IRQ_MULTI_HANDLER
110	select GENERIC_IRQ_SHOW
111	select GENERIC_IRQ_SHOW_LEVEL
112	select GENERIC_LIB_DEVMEM_IS_ALLOWED
113	select GENERIC_PCI_IOMAP
114	select GENERIC_PTDUMP if MMU
115	select GENERIC_SCHED_CLOCK
116	select GENERIC_SMP_IDLE_THREAD
117	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
118	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
119	select HARDIRQS_SW_RESEND
120	select HAS_IOPORT if MMU
121	select HAVE_ALIGNED_STRUCT_PAGE
122	select HAVE_ARCH_AUDITSYSCALL
123	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
124	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT
125	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
126	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
127	select HAVE_ARCH_KASAN if MMU && 64BIT
128	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
129	select HAVE_ARCH_KFENCE if MMU && 64BIT
130	select HAVE_ARCH_KGDB if !XIP_KERNEL
131	select HAVE_ARCH_KGDB_QXFER_PKT
132	select HAVE_ARCH_MMAP_RND_BITS if MMU
133	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
134	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
135	select HAVE_ARCH_SECCOMP_FILTER
136	select HAVE_ARCH_STACKLEAK
137	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
138	select HAVE_ARCH_TRACEHOOK
139	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
140	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
141	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
142	select HAVE_ASM_MODVERSIONS
143	select HAVE_CONTEXT_TRACKING_USER
144	select HAVE_DEBUG_KMEMLEAK
145	select HAVE_DMA_CONTIGUOUS if MMU
146	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE)
147	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
148	select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
149	select HAVE_FTRACE_GRAPH_FUNC
150	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
151	select HAVE_FUNCTION_GRAPH_TRACER
152	select HAVE_FUNCTION_GRAPH_FREGS
153	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
154	select HAVE_EBPF_JIT if MMU
155	select HAVE_GUP_FAST if MMU
156	select HAVE_FUNCTION_ARG_ACCESS_API
157	select HAVE_FUNCTION_ERROR_INJECTION
158	select HAVE_GCC_PLUGINS
159	select HAVE_GENERIC_VDSO if MMU && 64BIT
160	select HAVE_IRQ_TIME_ACCOUNTING
161	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
162	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
163	select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT
164	select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT
165	select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT
166	select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT
167	select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT
168	select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT
169	select HAVE_KPROBES if !XIP_KERNEL
170	select HAVE_KRETPROBES if !XIP_KERNEL
171	# https://github.com/ClangBuiltLinux/linux/issues/1881
172	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
173	select HAVE_MOVE_PMD
174	select HAVE_MOVE_PUD
175	select HAVE_PAGE_SIZE_4KB
176	select HAVE_PCI
177	select HAVE_PERF_EVENTS
178	select HAVE_PERF_REGS
179	select HAVE_PERF_USER_STACK_DUMP
180	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
181	select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL
182	select HAVE_REGS_AND_STACK_ACCESS_API
183	select HAVE_RETHOOK if !XIP_KERNEL
184	select HAVE_RSEQ
185	select HAVE_RUST if RUSTC_SUPPORTS_RISCV && CC_IS_CLANG
186	select HAVE_SAMPLE_FTRACE_DIRECT
187	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
188	select HAVE_STACKPROTECTOR
189	select HAVE_SYSCALL_TRACEPOINTS
190	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
191	select IRQ_DOMAIN
192	select IRQ_FORCED_THREADING
193	select KASAN_VMALLOC if KASAN
194	select LOCK_MM_AND_FIND_VMA
195	select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU
196	select MODULES_USE_ELF_RELA if MODULES
197	select OF
198	select OF_EARLY_FLATTREE
199	select OF_IRQ
200	select PCI_DOMAINS_GENERIC if PCI
201	select PCI_ECAM if (ACPI && PCI)
202	select PCI_MSI if PCI
203	select RISCV_ALTERNATIVE if !XIP_KERNEL
204	select RISCV_APLIC
205	select RISCV_IMSIC
206	select RISCV_INTC
207	select RISCV_TIMER if RISCV_SBI
208	select SIFIVE_PLIC
209	select SPARSE_IRQ
210	select SYSCTL_EXCEPTION_TRACE
211	select THREAD_INFO_IN_TASK
212	select TRACE_IRQFLAGS_SUPPORT
213	select UACCESS_MEMCPY if !MMU
214	select USER_STACKTRACE_SUPPORT
215	select ZONE_DMA32 if 64BIT
216
217config RUSTC_SUPPORTS_RISCV
218	def_bool y
219	depends on 64BIT
220	# Shadow call stack requires rustc version 1.82+ due to use of the
221	# -Zsanitizer=shadow-call-stack flag.
222	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
223
224config CLANG_SUPPORTS_DYNAMIC_FTRACE
225	def_bool CC_IS_CLANG
226	# https://github.com/ClangBuiltLinux/linux/issues/1817
227	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
228
229config GCC_SUPPORTS_DYNAMIC_FTRACE
230	def_bool CC_IS_GCC
231	depends on $(cc-option,-fpatchable-function-entry=8)
232
233config HAVE_SHADOW_CALL_STACK
234	def_bool $(cc-option,-fsanitize=shadow-call-stack)
235	# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
236	depends on $(ld-option,--no-relax-gp)
237
238config RISCV_USE_LINKER_RELAXATION
239	def_bool y
240	# https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
241	depends on !LD_IS_LLD || LLD_VERSION >= 150000
242
243# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6
244config ARCH_HAS_BROKEN_DWARF5
245	def_bool y
246	depends on RISCV_USE_LINKER_RELAXATION
247	# https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a
248	depends on AS_IS_LLVM && AS_VERSION < 180000
249	# https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77
250	depends on LD_IS_LLD && LLD_VERSION < 180000
251
252config ARCH_MMAP_RND_BITS_MIN
253	default 18 if 64BIT
254	default 8
255
256config ARCH_MMAP_RND_COMPAT_BITS_MIN
257	default 8
258
259# max bits determined by the following formula:
260#  VA_BITS - PAGE_SHIFT - 3
261config ARCH_MMAP_RND_BITS_MAX
262	default 24 if 64BIT # SV39 based
263	default 17
264
265config ARCH_MMAP_RND_COMPAT_BITS_MAX
266	default 17
267
268# set if we run in machine mode, cleared if we run in supervisor mode
269config RISCV_M_MODE
270	bool "Build a kernel that runs in machine mode"
271	depends on !MMU
272	default y
273	help
274	  Select this option if you want to run the kernel in M-mode,
275	  without the assistance of any other firmware.
276
277# set if we are running in S-mode and can use SBI calls
278config RISCV_SBI
279	bool
280	depends on !RISCV_M_MODE
281	default y
282
283config MMU
284	bool "MMU-based Paged Memory Management Support"
285	default y
286	help
287	  Select if you want MMU-based virtualised addressing space
288	  support by paged memory management. If unsure, say 'Y'.
289
290config PAGE_OFFSET
291	hex
292	default 0x80000000 if !MMU && RISCV_M_MODE
293	default 0x80200000 if !MMU
294	default 0xc0000000 if 32BIT
295	default 0xff60000000000000 if 64BIT
296
297config KASAN_SHADOW_OFFSET
298	hex
299	depends on KASAN_GENERIC
300	default 0xdfffffff00000000 if 64BIT
301	default 0xffffffff if 32BIT
302
303config ARCH_FLATMEM_ENABLE
304	def_bool !NUMA
305
306config ARCH_SPARSEMEM_ENABLE
307	def_bool y
308	depends on MMU
309	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
310	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
311
312config ARCH_SELECT_MEMORY_MODEL
313	def_bool ARCH_SPARSEMEM_ENABLE
314
315config ARCH_SUPPORTS_UPROBES
316	def_bool y
317
318config STACKTRACE_SUPPORT
319	def_bool y
320
321config GENERIC_BUG
322	def_bool y
323	depends on BUG
324	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
325
326config GENERIC_BUG_RELATIVE_POINTERS
327	bool
328
329config GENERIC_CALIBRATE_DELAY
330	def_bool y
331
332config GENERIC_CSUM
333	def_bool y
334
335config GENERIC_HWEIGHT
336	def_bool y
337
338config FIX_EARLYCON_MEM
339	def_bool MMU
340
341config ILLEGAL_POINTER_VALUE
342	hex
343	default 0 if 32BIT
344	default 0xdead000000000000 if 64BIT
345
346config PGTABLE_LEVELS
347	int
348	default 5 if 64BIT
349	default 2
350
351config LOCKDEP_SUPPORT
352	def_bool y
353
354config RISCV_DMA_NONCOHERENT
355	bool
356	select ARCH_HAS_DMA_PREP_COHERENT
357	select ARCH_HAS_SETUP_DMA_OPS
358	select ARCH_HAS_SYNC_DMA_FOR_CPU
359	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
360	select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB
361
362config RISCV_NONSTANDARD_CACHE_OPS
363	bool
364	help
365	  This enables function pointer support for non-standard noncoherent
366	  systems to handle cache management.
367
368config AS_HAS_INSN
369	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
370
371config AS_HAS_OPTION_ARCH
372	# https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
373	def_bool y
374	depends on $(as-instr, .option arch$(comma) +m)
375
376source "arch/riscv/Kconfig.socs"
377source "arch/riscv/Kconfig.errata"
378
379menu "Platform type"
380
381config NONPORTABLE
382	bool "Allow configurations that result in non-portable kernels"
383	help
384	  RISC-V kernel binaries are compatible between all known systems
385	  whenever possible, but there are some use cases that can only be
386	  satisfied by configurations that result in kernel binaries that are
387	  not portable between systems.
388
389	  Selecting N does not guarantee kernels will be portable to all known
390	  systems.  Selecting any of the options guarded by NONPORTABLE will
391	  result in kernel binaries that are unlikely to be portable between
392	  systems.
393
394	  If unsure, say N.
395
396choice
397	prompt "Base ISA"
398	default ARCH_RV64I
399	help
400	  This selects the base ISA that this kernel will target and must match
401	  the target platform.
402
403config ARCH_RV32I
404	bool "RV32I"
405	depends on NONPORTABLE
406	select 32BIT
407	select GENERIC_LIB_ASHLDI3
408	select GENERIC_LIB_ASHRDI3
409	select GENERIC_LIB_LSHRDI3
410	select GENERIC_LIB_UCMPDI2
411
412config ARCH_RV64I
413	bool "RV64I"
414	select 64BIT
415	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
416	select SWIOTLB if MMU
417
418endchoice
419
420# We must be able to map all physical memory into the kernel, but the compiler
421# is still a bit more efficient when generating code if it's setup in a manner
422# such that it can only map 2GiB of memory.
423choice
424	prompt "Kernel Code Model"
425	default CMODEL_MEDLOW if 32BIT
426	default CMODEL_MEDANY if 64BIT
427
428	config CMODEL_MEDLOW
429		bool "medium low code model"
430	config CMODEL_MEDANY
431		bool "medium any code model"
432endchoice
433
434config MODULE_SECTIONS
435	bool
436	select HAVE_MOD_ARCH_SPECIFIC
437
438config SMP
439	bool "Symmetric Multi-Processing"
440	help
441	  This enables support for systems with more than one CPU.  If
442	  you say N here, the kernel will run on single and
443	  multiprocessor machines, but will use only one CPU of a
444	  multiprocessor machine. If you say Y here, the kernel will run
445	  on many, but not all, single processor machines. On a single
446	  processor machine, the kernel will run faster if you say N
447	  here.
448
449	  If you don't know what to do here, say N.
450
451config SCHED_MC
452	bool "Multi-core scheduler support"
453	depends on SMP
454	help
455	  Multi-core scheduler support improves the CPU scheduler's decision
456	  making when dealing with multi-core CPU chips at a cost of slightly
457	  increased overhead in some places. If unsure say N here.
458
459config NR_CPUS
460	int "Maximum number of CPUs (2-512)"
461	depends on SMP
462	range 2 512 if !RISCV_SBI_V01
463	range 2 32 if RISCV_SBI_V01 && 32BIT
464	range 2 64 if RISCV_SBI_V01 && 64BIT
465	default "32" if 32BIT
466	default "64" if 64BIT
467
468config HOTPLUG_CPU
469	bool "Support for hot-pluggable CPUs"
470	depends on SMP
471	select GENERIC_IRQ_MIGRATION
472	help
473
474	  Say Y here to experiment with turning CPUs off and on.  CPUs
475	  can be controlled through /sys/devices/system/cpu.
476
477	  Say N if you want to disable CPU hotplug.
478
479choice
480	prompt "CPU Tuning"
481	default TUNE_GENERIC
482
483config TUNE_GENERIC
484	bool "generic"
485
486endchoice
487
488# Common NUMA Features
489config NUMA
490	bool "NUMA Memory Allocation and Scheduler Support"
491	depends on SMP && MMU
492	select ARCH_SUPPORTS_NUMA_BALANCING
493	select GENERIC_ARCH_NUMA
494	select HAVE_SETUP_PER_CPU_AREA
495	select NEED_PER_CPU_EMBED_FIRST_CHUNK
496	select NEED_PER_CPU_PAGE_FIRST_CHUNK
497	select OF_NUMA
498	select USE_PERCPU_NUMA_NODE_ID
499	help
500	  Enable NUMA (Non-Uniform Memory Access) support.
501
502	  The kernel will try to allocate memory used by a CPU on the
503	  local memory of the CPU and add some more NUMA awareness to the kernel.
504
505config NODES_SHIFT
506	int "Maximum NUMA Nodes (as a power of 2)"
507	range 1 10
508	default "2"
509	depends on NUMA
510	help
511	  Specify the maximum number of NUMA Nodes available on the target
512	  system.  Increases memory reserved to accommodate various tables.
513
514choice
515	prompt "RISC-V spinlock type"
516	default RISCV_COMBO_SPINLOCKS
517
518config RISCV_TICKET_SPINLOCKS
519	bool "Using ticket spinlock"
520
521config RISCV_QUEUED_SPINLOCKS
522	bool "Using queued spinlock"
523	depends on SMP && MMU && NONPORTABLE
524	select ARCH_USE_QUEUED_SPINLOCKS
525	help
526	  The queued spinlock implementation requires the forward progress
527	  guarantee of cmpxchg()/xchg() atomic operations: CAS with Zabha or
528	  LR/SC with Ziccrse provide such guarantee.
529
530	  Select this if and only if Zabha or Ziccrse is available on your
531	  platform, RISCV_QUEUED_SPINLOCKS must not be selected for platforms
532	  without one of those extensions.
533
534	  If unsure, select RISCV_COMBO_SPINLOCKS, which will use qspinlocks
535	  when supported and otherwise ticket spinlocks.
536
537config RISCV_COMBO_SPINLOCKS
538	bool "Using combo spinlock"
539	depends on SMP && MMU
540	select ARCH_USE_QUEUED_SPINLOCKS
541	help
542	  Embed both queued spinlock and ticket lock so that the spinlock
543	  implementation can be chosen at runtime.
544
545endchoice
546
547config RISCV_ALTERNATIVE
548	bool
549	depends on !XIP_KERNEL
550	help
551	  This Kconfig allows the kernel to automatically patch the
552	  erratum or cpufeature required by the execution platform at run
553	  time. The code patching overhead is minimal, as it's only done
554	  once at boot and once on each module load.
555
556config RISCV_ALTERNATIVE_EARLY
557	bool
558	depends on RISCV_ALTERNATIVE
559	help
560	  Allows early patching of the kernel for special errata
561
562config RISCV_ISA_C
563	bool "Emit compressed instructions when building Linux"
564	default y
565	help
566	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
567	  when building Linux, which results in compressed instructions in the
568	  Linux binary.
569
570	  If you don't know what to do here, say Y.
571
572config RISCV_ISA_SUPM
573	bool "Supm extension for userspace pointer masking"
574	depends on 64BIT
575	default y
576	help
577	  Add support for pointer masking in userspace (Supm) when the
578	  underlying hardware extension (Smnpm or Ssnpm) is detected at boot.
579
580	  If this option is disabled, userspace will be unable to use
581	  the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API.
582
583config RISCV_ISA_SVNAPOT
584	bool "Svnapot extension support for supervisor mode NAPOT pages"
585	depends on 64BIT && MMU
586	depends on RISCV_ALTERNATIVE
587	default y
588	help
589	  Allow kernel to detect the Svnapot ISA-extension dynamically at boot
590	  time and enable its usage.
591
592	  The Svnapot extension is used to mark contiguous PTEs as a range
593	  of contiguous virtual-to-physical translations for a naturally
594	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
595	  size. When HUGETLBFS is also selected this option unconditionally
596	  allocates some memory for each NAPOT page size supported by the kernel.
597	  When optimizing for low memory consumption and for platforms without
598	  the Svnapot extension, it may be better to say N here.
599
600	  If you don't know what to do here, say Y.
601
602config RISCV_ISA_SVPBMT
603	bool "Svpbmt extension support for supervisor mode page-based memory types"
604	depends on 64BIT && MMU
605	depends on RISCV_ALTERNATIVE
606	default y
607	help
608	   Adds support to dynamically detect the presence of the Svpbmt
609	   ISA-extension (Supervisor-mode: page-based memory types) and
610	   enable its usage.
611
612	   The memory type for a page contains a combination of attributes
613	   that indicate the cacheability, idempotency, and ordering
614	   properties for access to that page.
615
616	   The Svpbmt extension is only available on 64-bit cpus.
617
618	   If you don't know what to do here, say Y.
619
620config TOOLCHAIN_HAS_V
621	bool
622	default y
623	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv)
624	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv)
625	depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800
626	depends on AS_HAS_OPTION_ARCH
627
628config RISCV_ISA_V
629	bool "VECTOR extension support"
630	depends on TOOLCHAIN_HAS_V
631	depends on FPU
632	select DYNAMIC_SIGFRAME
633	default y
634	help
635	  Say N here if you want to disable all vector related procedure
636	  in the kernel.
637
638	  If you don't know what to do here, say Y.
639
640config RISCV_ISA_V_DEFAULT_ENABLE
641	bool "Enable userspace Vector by default"
642	depends on RISCV_ISA_V
643	default y
644	help
645	  Say Y here if you want to enable Vector in userspace by default.
646	  Otherwise, userspace has to make explicit prctl() call to enable
647	  Vector, or enable it via the sysctl interface.
648
649	  If you don't know what to do here, say Y.
650
651config RISCV_ISA_V_UCOPY_THRESHOLD
652	int "Threshold size for vectorized user copies"
653	depends on RISCV_ISA_V
654	default 768
655	help
656	  Prefer using vectorized copy_to_user()/copy_from_user() when the
657	  workload size exceeds this value.
658
659config RISCV_ISA_V_PREEMPTIVE
660	bool "Run kernel-mode Vector with kernel preemption"
661	depends on PREEMPTION
662	depends on RISCV_ISA_V
663	default y
664	help
665	  Usually, in-kernel SIMD routines are run with preemption disabled.
666	  Functions which envoke long running SIMD thus must yield core's
667	  vector unit to prevent blocking other tasks for too long.
668
669	  This config allows kernel to run SIMD without explicitly disable
670	  preemption. Enabling this config will result in higher memory
671	  consumption due to the allocation of per-task's kernel Vector context.
672
673config RISCV_ISA_ZAWRS
674	bool "Zawrs extension support for more efficient busy waiting"
675	depends on RISCV_ALTERNATIVE
676	default y
677	help
678	  The Zawrs extension defines instructions to be used in polling loops
679	  which allow a hart to enter a low-power state or to trap to the
680	  hypervisor while waiting on a store to a memory location. Enable the
681	  use of these instructions in the kernel when the Zawrs extension is
682	  detected at boot.
683
684config TOOLCHAIN_HAS_ZABHA
685	bool
686	default y
687	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zabha)
688	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zabha)
689	depends on AS_HAS_OPTION_ARCH
690
691config RISCV_ISA_ZABHA
692	bool "Zabha extension support for atomic byte/halfword operations"
693	depends on TOOLCHAIN_HAS_ZABHA
694	depends on RISCV_ALTERNATIVE
695	default y
696	help
697	  Enable the use of the Zabha ISA-extension to implement kernel
698	  byte/halfword atomic memory operations when it is detected at boot.
699
700	  If you don't know what to do here, say Y.
701
702config TOOLCHAIN_HAS_ZACAS
703	bool
704	default y
705	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas)
706	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas)
707	depends on AS_HAS_OPTION_ARCH
708
709config RISCV_ISA_ZACAS
710	bool "Zacas extension support for atomic CAS"
711	depends on TOOLCHAIN_HAS_ZACAS
712	depends on RISCV_ALTERNATIVE
713	default y
714	help
715	  Enable the use of the Zacas ISA-extension to implement kernel atomic
716	  cmpxchg operations when it is detected at boot.
717
718	  If you don't know what to do here, say Y.
719
720config TOOLCHAIN_HAS_ZBB
721	bool
722	default y
723	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
724	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
725	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
726	depends on AS_HAS_OPTION_ARCH
727
728# This symbol indicates that the toolchain supports all v1.0 vector crypto
729# extensions, including Zvk*, Zvbb, and Zvbc.  LLVM added all of these at once.
730# binutils added all except Zvkb, then added Zvkb.  So we just check for Zvkb.
731config TOOLCHAIN_HAS_VECTOR_CRYPTO
732	def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb)
733	depends on AS_HAS_OPTION_ARCH
734
735config RISCV_ISA_ZBA
736	bool "Zba extension support for bit manipulation instructions"
737	default y
738	help
739	   Add support for enabling optimisations in the kernel when the Zba
740	   extension is detected at boot.
741
742	   The Zba extension provides instructions to accelerate the generation
743	   of addresses that index into arrays of basic data types.
744
745	   If you don't know what to do here, say Y.
746
747config RISCV_ISA_ZBB
748	bool "Zbb extension support for bit manipulation instructions"
749	depends on TOOLCHAIN_HAS_ZBB
750	depends on RISCV_ALTERNATIVE
751	default y
752	help
753	   Adds support to dynamically detect the presence of the ZBB
754	   extension (basic bit manipulation) and enable its usage.
755
756	   The Zbb extension provides instructions to accelerate a number
757	   of bit-specific operations (count bit population, sign extending,
758	   bitrotation, etc).
759
760	   If you don't know what to do here, say Y.
761
762config TOOLCHAIN_HAS_ZBC
763	bool
764	default y
765	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc)
766	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc)
767	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
768	depends on AS_HAS_OPTION_ARCH
769
770config RISCV_ISA_ZBC
771	bool "Zbc extension support for carry-less multiplication instructions"
772	depends on TOOLCHAIN_HAS_ZBC
773	depends on MMU
774	depends on RISCV_ALTERNATIVE
775	default y
776	help
777	   Adds support to dynamically detect the presence of the Zbc
778	   extension (carry-less multiplication) and enable its usage.
779
780	   The Zbc extension could accelerate CRC (cyclic redundancy check)
781	   calculations.
782
783	   If you don't know what to do here, say Y.
784
785config RISCV_ISA_ZICBOM
786	bool "Zicbom extension support for non-coherent DMA operation"
787	depends on MMU
788	depends on RISCV_ALTERNATIVE
789	default y
790	select RISCV_DMA_NONCOHERENT
791	select DMA_DIRECT_REMAP
792	help
793	   Adds support to dynamically detect the presence of the ZICBOM
794	   extension (Cache Block Management Operations) and enable its
795	   usage.
796
797	   The Zicbom extension can be used to handle for example
798	   non-coherent DMA support on devices that need it.
799
800	   If you don't know what to do here, say Y.
801
802config RISCV_ISA_ZICBOZ
803	bool "Zicboz extension support for faster zeroing of memory"
804	depends on RISCV_ALTERNATIVE
805	default y
806	help
807	   Enable the use of the Zicboz extension (cbo.zero instruction)
808	   when available.
809
810	   The Zicboz extension is used for faster zeroing of memory.
811
812	   If you don't know what to do here, say Y.
813
814config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
815	def_bool y
816	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
817	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
818	depends on AS_IS_GNU && AS_VERSION >= 23600
819	help
820	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
821	  20191213 version, which moves some instructions from the I extension to
822	  the Zicsr and Zifencei extensions. This requires explicitly specifying
823	  Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
824	  and Zifencei are supported in binutils from version 2.36 onwards.
825	  To make life easier, and avoid forcing toolchains that default to a
826	  newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
827	  For clang < 17 or GCC < 11.3.0, for which this is not possible or need
828	  special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
829
830config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
831	def_bool y
832	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
833	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
834	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671
835	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300)
836	help
837	  Certain versions of clang and GCC do not support zicsr and zifencei via
838	  -march. This option causes an older ISA spec compatible with these older
839	  versions of clang and GCC to be passed to GAS, which has the same result
840	  as passing zicsr and zifencei to -march.
841
842config FPU
843	bool "FPU support"
844	default y
845	help
846	  Say N here if you want to disable all floating-point related procedure
847	  in the kernel.
848
849	  If you don't know what to do here, say Y.
850
851config IRQ_STACKS
852	bool "Independent irq & softirq stacks" if EXPERT
853	default y
854	select HAVE_IRQ_EXIT_ON_IRQ_STACK
855	select HAVE_SOFTIRQ_ON_OWN_STACK
856	help
857	  Add independent irq & softirq stacks for percpu to prevent kernel stack
858	  overflows. We may save some memory footprint by disabling IRQ_STACKS.
859
860config THREAD_SIZE_ORDER
861	int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT
862	range 0 4
863	default 1 if 32BIT
864	default 2
865	help
866	  Specify the Pages of thread stack size (from 4KB to 64KB), which also
867	  affects irq stack size, which is equal to thread stack size.
868
869config RISCV_MISALIGNED
870	bool
871	help
872	  Embed support for detecting and emulating misaligned
873	  scalar or vector loads and stores.
874
875config RISCV_SCALAR_MISALIGNED
876	bool
877	select RISCV_MISALIGNED
878	select SYSCTL_ARCH_UNALIGN_ALLOW
879	help
880	  Embed support for emulating misaligned loads and stores.
881
882config RISCV_VECTOR_MISALIGNED
883	bool
884	select RISCV_MISALIGNED
885	depends on RISCV_ISA_V
886	help
887	  Enable detecting support for vector misaligned loads and stores.
888
889choice
890	prompt "Unaligned Accesses Support"
891	default RISCV_PROBE_UNALIGNED_ACCESS
892	help
893	  This determines the level of support for unaligned accesses. This
894	  information is used by the kernel to perform optimizations. It is also
895	  exposed to user space via the hwprobe syscall. The hardware will be
896	  probed at boot by default.
897
898config RISCV_PROBE_UNALIGNED_ACCESS
899	bool "Probe for hardware unaligned access support"
900	select RISCV_SCALAR_MISALIGNED
901	help
902	  During boot, the kernel will run a series of tests to determine the
903	  speed of unaligned accesses. This probing will dynamically determine
904	  the speed of unaligned accesses on the underlying system. If unaligned
905	  memory accesses trap into the kernel as they are not supported by the
906	  system, the kernel will emulate the unaligned accesses to preserve the
907	  UABI.
908
909config RISCV_EMULATED_UNALIGNED_ACCESS
910	bool "Emulate unaligned access where system support is missing"
911	select RISCV_SCALAR_MISALIGNED
912	help
913	  If unaligned memory accesses trap into the kernel as they are not
914	  supported by the system, the kernel will emulate the unaligned
915	  accesses to preserve the UABI. When the underlying system does support
916	  unaligned accesses, the unaligned accesses are assumed to be slow.
917
918config RISCV_SLOW_UNALIGNED_ACCESS
919	bool "Assume the system supports slow unaligned memory accesses"
920	depends on NONPORTABLE
921	help
922	  Assume that the system supports slow unaligned memory accesses. The
923	  kernel and userspace programs may not be able to run at all on systems
924	  that do not support unaligned memory accesses.
925
926config RISCV_EFFICIENT_UNALIGNED_ACCESS
927	bool "Assume the system supports fast unaligned memory accesses"
928	depends on NONPORTABLE
929	select DCACHE_WORD_ACCESS if MMU
930	select HAVE_EFFICIENT_UNALIGNED_ACCESS
931	help
932	  Assume that the system supports fast unaligned memory accesses. When
933	  enabled, this option improves the performance of the kernel on such
934	  systems. However, the kernel and userspace programs will run much more
935	  slowly, or will not be able to run at all, on systems that do not
936	  support efficient unaligned memory accesses.
937
938endchoice
939
940choice
941	prompt "Vector unaligned Accesses Support"
942	depends on RISCV_ISA_V
943	default RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
944	help
945	  This determines the level of support for vector unaligned accesses. This
946	  information is used by the kernel to perform optimizations. It is also
947	  exposed to user space via the hwprobe syscall. The hardware will be
948	  probed at boot by default.
949
950config RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
951	bool "Probe speed of vector unaligned accesses"
952	select RISCV_VECTOR_MISALIGNED
953	depends on RISCV_ISA_V
954	help
955	  During boot, the kernel will run a series of tests to determine the
956	  speed of vector unaligned accesses if they are supported. This probing
957	  will dynamically determine the speed of vector unaligned accesses on
958	  the underlying system if they are supported.
959
960config RISCV_SLOW_VECTOR_UNALIGNED_ACCESS
961	bool "Assume the system supports slow vector unaligned memory accesses"
962	depends on NONPORTABLE
963	help
964	  Assume that the system supports slow vector unaligned memory accesses. The
965	  kernel and userspace programs may not be able to run at all on systems
966	  that do not support unaligned memory accesses.
967
968config RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS
969	bool "Assume the system supports fast vector unaligned memory accesses"
970	depends on NONPORTABLE
971	help
972	  Assume that the system supports fast vector unaligned memory accesses. When
973	  enabled, this option improves the performance of the kernel on such
974	  systems. However, the kernel and userspace programs will run much more
975	  slowly, or will not be able to run at all, on systems that do not
976	  support efficient unaligned memory accesses.
977
978endchoice
979
980source "arch/riscv/Kconfig.vendor"
981
982endmenu # "Platform type"
983
984menu "Kernel features"
985
986source "kernel/Kconfig.hz"
987
988config RISCV_SBI_V01
989	bool "SBI v0.1 support"
990	depends on RISCV_SBI
991	help
992	  This config allows kernel to use SBI v0.1 APIs. This will be
993	  deprecated in future once legacy M-mode software are no longer in use.
994
995config RISCV_BOOT_SPINWAIT
996	bool "Spinwait booting method"
997	depends on SMP
998	default y if RISCV_SBI_V01 || RISCV_M_MODE
999	help
1000	  This enables support for booting Linux via spinwait method. In the
1001	  spinwait method, all cores randomly jump to Linux. One of the cores
1002	  gets chosen via lottery and all other keep spinning on a percpu
1003	  variable. This method cannot support CPU hotplug and sparse hartid
1004	  scheme. It should be only enabled for M-mode Linux or platforms relying
1005	  on older firmware without SBI HSM extension. All other platforms should
1006	  rely on ordered booting via SBI HSM extension which gets chosen
1007	  dynamically at runtime if the firmware supports it.
1008
1009	  Since spinwait is incompatible with sparse hart IDs, it requires
1010	  NR_CPUS be large enough to contain the physical hart ID of the first
1011	  hart to enter Linux.
1012
1013	  If unsure what to do here, say N.
1014
1015config ARCH_SUPPORTS_KEXEC
1016	def_bool y
1017
1018config ARCH_SELECTS_KEXEC
1019	def_bool y
1020	depends on KEXEC
1021	select HOTPLUG_CPU if SMP
1022
1023config ARCH_SUPPORTS_KEXEC_FILE
1024	def_bool 64BIT
1025
1026config ARCH_SELECTS_KEXEC_FILE
1027	def_bool y
1028	depends on KEXEC_FILE
1029	select HAVE_IMA_KEXEC if IMA
1030	select KEXEC_ELF
1031
1032config ARCH_SUPPORTS_KEXEC_PURGATORY
1033	def_bool ARCH_SUPPORTS_KEXEC_FILE
1034
1035config ARCH_SUPPORTS_CRASH_DUMP
1036	def_bool y
1037
1038config ARCH_DEFAULT_CRASH_DUMP
1039	def_bool y
1040
1041config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1042	def_bool CRASH_RESERVE
1043
1044config COMPAT
1045	bool "Kernel support for 32-bit U-mode"
1046	default 64BIT
1047	depends on 64BIT && MMU
1048	help
1049	  This option enables support for a 32-bit U-mode running under a 64-bit
1050	  kernel at S-mode. riscv32-specific components such as system calls,
1051	  the user helper functions (vdso), signal rt_frame functions and the
1052	  ptrace interface are handled appropriately by the kernel.
1053
1054	  If you want to execute 32-bit userspace applications, say Y.
1055
1056config PARAVIRT
1057	bool "Enable paravirtualization code"
1058	depends on RISCV_SBI
1059	help
1060	  This changes the kernel so it can modify itself when it is run
1061	  under a hypervisor, potentially improving performance significantly
1062	  over full virtualization.
1063
1064config PARAVIRT_TIME_ACCOUNTING
1065	bool "Paravirtual steal time accounting"
1066	depends on PARAVIRT
1067	help
1068	  Select this option to enable fine granularity task steal time
1069	  accounting. Time spent executing other tasks in parallel with
1070	  the current vCPU is discounted from the vCPU power. To account for
1071	  that, there can be a small performance impact.
1072
1073	  If in doubt, say N here.
1074
1075config RELOCATABLE
1076	bool "Build a relocatable kernel"
1077	depends on MMU && 64BIT && !XIP_KERNEL
1078	select MODULE_SECTIONS if MODULES
1079	help
1080          This builds a kernel as a Position Independent Executable (PIE),
1081          which retains all relocation metadata required to relocate the
1082          kernel binary at runtime to a different virtual address than the
1083          address it was linked at.
1084          Since RISCV uses the RELA relocation format, this requires a
1085          relocation pass at runtime even if the kernel is loaded at the
1086          same address it was linked at.
1087
1088          If unsure, say N.
1089
1090config RANDOMIZE_BASE
1091        bool "Randomize the address of the kernel image"
1092        select RELOCATABLE
1093        depends on MMU && 64BIT && !XIP_KERNEL
1094        help
1095          Randomizes the virtual address at which the kernel image is
1096          loaded, as a security feature that deters exploit attempts
1097          relying on knowledge of the location of kernel internals.
1098
1099          It is the bootloader's job to provide entropy, by passing a
1100          random u64 value in /chosen/kaslr-seed at kernel entry.
1101
1102          When booting via the UEFI stub, it will invoke the firmware's
1103          EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1104          to the kernel proper. In addition, it will randomise the physical
1105          location of the kernel Image as well.
1106
1107          If unsure, say N.
1108
1109endmenu # "Kernel features"
1110
1111menu "Boot options"
1112
1113config CMDLINE
1114	string "Built-in kernel command line"
1115	help
1116	  For most platforms, the arguments for the kernel's command line
1117	  are provided at run-time, during boot. However, there are cases
1118	  where either no arguments are being provided or the provided
1119	  arguments are insufficient or even invalid.
1120
1121	  When that occurs, it is possible to define a built-in command
1122	  line here and choose how the kernel should use it later on.
1123
1124choice
1125	prompt "Built-in command line usage"
1126	depends on CMDLINE != ""
1127	default CMDLINE_FALLBACK
1128	help
1129	  Choose how the kernel will handle the provided built-in command
1130	  line.
1131
1132config CMDLINE_FALLBACK
1133	bool "Use bootloader kernel arguments if available"
1134	help
1135	  Use the built-in command line as fallback in case we get nothing
1136	  during boot. This is the default behaviour.
1137
1138config CMDLINE_EXTEND
1139	bool "Extend bootloader kernel arguments"
1140	help
1141	  The command-line arguments provided during boot will be
1142	  appended to the built-in command line. This is useful in
1143	  cases where the provided arguments are insufficient and
1144	  you don't want to or cannot modify them.
1145
1146config CMDLINE_FORCE
1147	bool "Always use the default kernel command string"
1148	help
1149	  Always use the built-in command line, even if we get one during
1150	  boot. This is useful in case you need to override the provided
1151	  command line on systems where you don't have or want control
1152	  over it.
1153
1154endchoice
1155
1156config EFI_STUB
1157	bool
1158
1159config EFI
1160	bool "UEFI runtime support"
1161	depends on OF && !XIP_KERNEL
1162	depends on MMU
1163	default y
1164	select ARCH_SUPPORTS_ACPI if 64BIT
1165	select EFI_GENERIC_STUB
1166	select EFI_PARAMS_FROM_FDT
1167	select EFI_RUNTIME_WRAPPERS
1168	select EFI_STUB
1169	select LIBFDT
1170	select RISCV_ISA_C
1171	select UCS2_STRING
1172	help
1173	  This option provides support for runtime services provided
1174	  by UEFI firmware (such as non-volatile variables, realtime
1175	  clock, and platform reset). A UEFI stub is also provided to
1176	  allow the kernel to be booted as an EFI application. This
1177	  is only useful on systems that have UEFI firmware.
1178
1179config DMI
1180	bool "Enable support for SMBIOS (DMI) tables"
1181	depends on EFI
1182	default y
1183	help
1184	  This enables SMBIOS/DMI feature for systems.
1185
1186	  This option is only useful on systems that have UEFI firmware.
1187	  However, even with this option, the resultant kernel should
1188	  continue to boot on existing non-UEFI platforms.
1189
1190config CC_HAVE_STACKPROTECTOR_TLS
1191	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
1192
1193config STACKPROTECTOR_PER_TASK
1194	def_bool y
1195	depends on !RANDSTRUCT
1196	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
1197
1198config PHYS_RAM_BASE_FIXED
1199	bool "Explicitly specified physical RAM address"
1200	depends on NONPORTABLE
1201	default n
1202
1203config PHYS_RAM_BASE
1204	hex "Platform Physical RAM address"
1205	depends on PHYS_RAM_BASE_FIXED
1206	default "0x80000000"
1207	help
1208	  This is the physical address of RAM in the system. It has to be
1209	  explicitly specified to run early relocations of read-write data
1210	  from flash to RAM.
1211
1212config XIP_KERNEL
1213	bool "Kernel Execute-In-Place from ROM"
1214	depends on MMU && SPARSEMEM && NONPORTABLE
1215	# This prevents XIP from being enabled by all{yes,mod}config, which
1216	# fail to build since XIP doesn't support large kernels.
1217	depends on !COMPILE_TEST
1218	select PHYS_RAM_BASE_FIXED
1219	help
1220	  Execute-In-Place allows the kernel to run from non-volatile storage
1221	  directly addressable by the CPU, such as NOR flash. This saves RAM
1222	  space since the text section of the kernel is not loaded from flash
1223	  to RAM.  Read-write sections, such as the data section and stack,
1224	  are still copied to RAM.  The XIP kernel is not compressed since
1225	  it has to run directly from flash, so it will take more space to
1226	  store it.  The flash address used to link the kernel object files,
1227	  and for storing it, is configuration dependent. Therefore, if you
1228	  say Y here, you must know the proper physical address where to
1229	  store the kernel image depending on your own flash memory usage.
1230
1231	  Also note that the make target becomes "make xipImage" rather than
1232	  "make zImage" or "make Image".  The final kernel binary to put in
1233	  ROM memory will be arch/riscv/boot/xipImage.
1234
1235	  SPARSEMEM is required because the kernel text and rodata that are
1236	  flash resident are not backed by memmap, then any attempt to get
1237	  a struct page on those regions will trigger a fault.
1238
1239	  If unsure, say N.
1240
1241config XIP_PHYS_ADDR
1242	hex "XIP Kernel Physical Location"
1243	depends on XIP_KERNEL
1244	default "0x21000000"
1245	help
1246	  This is the physical address in your flash memory the kernel will
1247	  be linked for and stored to.  This address is dependent on your
1248	  own flash usage.
1249
1250config RISCV_ISA_FALLBACK
1251	bool "Permit falling back to parsing riscv,isa for extension support by default"
1252	default y
1253	help
1254	  Parsing the "riscv,isa" devicetree property has been deprecated and
1255	  replaced by a list of explicitly defined strings. For compatibility
1256	  with existing platforms, the kernel will fall back to parsing the
1257	  "riscv,isa" property if the replacements are not found.
1258
1259	  Selecting N here will result in a kernel that does not use the
1260	  fallback, unless the commandline "riscv_isa_fallback" parameter is
1261	  present.
1262
1263	  Please see the dt-binding, located at
1264	  Documentation/devicetree/bindings/riscv/extensions.yaml for details
1265	  on the replacement properties, "riscv,isa-base" and
1266	  "riscv,isa-extensions".
1267
1268config BUILTIN_DTB
1269	bool "Built-in device tree"
1270	depends on OF && NONPORTABLE
1271	help
1272	  Build a device tree into the Linux image.
1273	  This option should be selected if no bootloader is being used.
1274	  If unsure, say N.
1275
1276
1277config BUILTIN_DTB_SOURCE
1278	string "Built-in device tree source"
1279	depends on BUILTIN_DTB
1280	help
1281	  DTS file path (without suffix, relative to arch/riscv/boot/dts)
1282	  for the DTS file that will be used to produce the DTB linked into the
1283	  kernel.
1284
1285endmenu # "Boot options"
1286
1287config PORTABLE
1288	bool
1289	default !NONPORTABLE
1290	select EFI
1291	select MMU
1292	select OF
1293
1294config ARCH_PROC_KCORE_TEXT
1295	def_bool y
1296
1297menu "Power management options"
1298
1299source "kernel/power/Kconfig"
1300
1301config ARCH_HIBERNATION_POSSIBLE
1302	def_bool y
1303
1304config ARCH_HIBERNATION_HEADER
1305	def_bool HIBERNATION
1306
1307config ARCH_SUSPEND_POSSIBLE
1308	def_bool y
1309
1310endmenu # "Power management options"
1311
1312menu "CPU Power Management"
1313
1314source "drivers/cpuidle/Kconfig"
1315
1316source "drivers/cpufreq/Kconfig"
1317
1318endmenu # "CPU Power Management"
1319
1320source "arch/riscv/kvm/Kconfig"
1321
1322source "drivers/acpi/Kconfig"
1323