xref: /linux/arch/riscv/Kconfig (revision 414aaef1537ac7f90dcb54e618864680aca2e197)
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_CRC32 if RISCV_ISA_ZBC
28	select ARCH_HAS_CRC64 if 64BIT && RISCV_ISA_ZBC
29	select ARCH_HAS_CRC_T10DIF if RISCV_ISA_ZBC
30	select ARCH_HAS_CURRENT_STACK_POINTER
31	select ARCH_HAS_DEBUG_VIRTUAL if MMU
32	select ARCH_HAS_DEBUG_VM_PGTABLE
33	select ARCH_HAS_DEBUG_WX
34	select ARCH_HAS_FAST_MULTIPLIER
35	select ARCH_HAS_FORTIFY_SOURCE
36	select ARCH_HAS_GCOV_PROFILE_ALL
37	select ARCH_HAS_GIGANTIC_PAGE
38	select ARCH_HAS_HW_PTE_YOUNG
39	select ARCH_HAS_KCOV
40	select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU
41	select ARCH_HAS_MEMBARRIER_CALLBACKS
42	select ARCH_HAS_MEMBARRIER_SYNC_CORE
43	select ARCH_HAS_MMIOWB
44	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
45	select ARCH_HAS_PMEM_API
46	select ARCH_HAS_PREEMPT_LAZY
47	select ARCH_HAS_PREPARE_SYNC_CORE_CMD
48	select ARCH_HAS_PTDUMP if MMU
49	select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU
50	select ARCH_HAS_PTE_SPECIAL
51	select ARCH_HAS_SET_DIRECT_MAP if MMU
52	select ARCH_HAS_SET_MEMORY if MMU
53	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
54	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
55	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
56	select ARCH_HAS_SYSCALL_WRAPPER
57	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
58	select ARCH_HAS_UBSAN
59	select ARCH_HAS_VDSO_ARCH_DATA if GENERIC_VDSO_DATA_STORE
60	select ARCH_KEEP_MEMBLOCK if ACPI
61	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
62	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
63	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
64	select ARCH_STACKWALK
65	select ARCH_SUPPORTS_ATOMIC_RMW
66	# clang >= 17: https://github.com/llvm/llvm-project/commit/62fa708ceb027713b386c7e0efda994f8bdc27e2
67	select ARCH_SUPPORTS_CFI_CLANG if CLANG_VERSION >= 170000
68	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
69	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
70	select ARCH_SUPPORTS_HUGETLBFS if MMU
71	# LLD >= 14: https://github.com/llvm/llvm-project/issues/50505
72	select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000
73	select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000
74	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS if 64BIT && MMU
75	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
76	select ARCH_SUPPORTS_PER_VMA_LOCK if MMU
77	select ARCH_SUPPORTS_RT
78	select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK
79	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
80	select ARCH_USE_MEMTEST
81	select ARCH_USE_QUEUED_RWLOCKS
82	select ARCH_USE_SYM_ANNOTATIONS
83	select ARCH_USES_CFI_TRAPS if CFI_CLANG
84	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
85	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
86	select ARCH_WANT_FRAME_POINTERS
87	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
88	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
89	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
90	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
91	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
92	select ARCH_WANTS_NO_INSTR
93	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
94	select ARCH_WEAK_RELEASE_ACQUIRE if ARCH_USE_QUEUED_SPINLOCKS
95	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
96	select BUILDTIME_TABLE_SORT if MMU
97	select CLINT_TIMER if RISCV_M_MODE
98	select CLONE_BACKWARDS
99	select COMMON_CLK
100	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
101	select DYNAMIC_FTRACE if FUNCTION_TRACER
102	select EDAC_SUPPORT
103	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
104	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
105	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
106	select GENERIC_ARCH_TOPOLOGY
107	select GENERIC_ATOMIC64 if !64BIT
108	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
109	select GENERIC_CPU_DEVICES
110	select GENERIC_CPU_VULNERABILITIES
111	select GENERIC_EARLY_IOREMAP
112	select GENERIC_ENTRY
113	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
114	select GENERIC_IDLE_POLL_SETUP
115	select GENERIC_IOREMAP if MMU
116	select GENERIC_IRQ_IPI if SMP
117	select GENERIC_IRQ_IPI_MUX if SMP
118	select GENERIC_IRQ_MULTI_HANDLER
119	select GENERIC_IRQ_SHOW
120	select GENERIC_IRQ_SHOW_LEVEL
121	select GENERIC_LIB_DEVMEM_IS_ALLOWED
122	select GENERIC_PENDING_IRQ if SMP
123	select GENERIC_PCI_IOMAP
124	select GENERIC_SCHED_CLOCK
125	select GENERIC_SMP_IDLE_THREAD
126	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
127	select GENERIC_VDSO_DATA_STORE if MMU
128	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
129	select HARDIRQS_SW_RESEND
130	select HAS_IOPORT if MMU
131	select HAVE_ALIGNED_STRUCT_PAGE
132	select HAVE_ARCH_AUDITSYSCALL
133	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
134	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT
135	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
136	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
137	select HAVE_ARCH_KASAN if MMU && 64BIT
138	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
139	select HAVE_ARCH_KFENCE if MMU && 64BIT
140	select HAVE_ARCH_KGDB if !XIP_KERNEL
141	select HAVE_ARCH_KGDB_QXFER_PKT
142	select HAVE_ARCH_MMAP_RND_BITS if MMU
143	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
144	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
145	select HAVE_ARCH_SECCOMP_FILTER
146	select HAVE_ARCH_STACKLEAK
147	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
148	select HAVE_ARCH_TRACEHOOK
149	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
150	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if 64BIT && MMU
151	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
152	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
153	select HAVE_ASM_MODVERSIONS
154	select HAVE_CONTEXT_TRACKING_USER
155	select HAVE_DEBUG_KMEMLEAK
156	select HAVE_DMA_CONTIGUOUS if MMU
157	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE)
158	select FUNCTION_ALIGNMENT_4B if HAVE_DYNAMIC_FTRACE && RISCV_ISA_C
159	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS if HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS
160	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG)
161	select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
162	select HAVE_FTRACE_GRAPH_FUNC
163	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
164	select HAVE_FUNCTION_GRAPH_TRACER if HAVE_DYNAMIC_FTRACE_WITH_ARGS
165	select HAVE_FUNCTION_GRAPH_FREGS
166	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && HAVE_DYNAMIC_FTRACE
167	select HAVE_EBPF_JIT if MMU
168	select HAVE_GUP_FAST if MMU
169	select HAVE_FUNCTION_ARG_ACCESS_API
170	select HAVE_FUNCTION_ERROR_INJECTION
171	select HAVE_GCC_PLUGINS
172	select HAVE_GENERIC_VDSO if MMU && 64BIT
173	select HAVE_IRQ_TIME_ACCOUNTING
174	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
175	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
176	select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT
177	select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT
178	select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT
179	select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT
180	select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT
181	select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT
182	select HAVE_KPROBES if !XIP_KERNEL
183	select HAVE_KRETPROBES if !XIP_KERNEL
184	# https://github.com/ClangBuiltLinux/linux/issues/1881
185	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
186	select HAVE_MOVE_PMD
187	select HAVE_MOVE_PUD
188	select HAVE_PAGE_SIZE_4KB
189	select HAVE_PCI
190	select HAVE_PERF_EVENTS
191	select HAVE_PERF_REGS
192	select HAVE_PERF_USER_STACK_DUMP
193	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
194	select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL
195	select HAVE_REGS_AND_STACK_ACCESS_API
196	select HAVE_RETHOOK if !XIP_KERNEL
197	select HAVE_RSEQ
198	select HAVE_RUST if RUSTC_SUPPORTS_RISCV && CC_IS_CLANG
199	select HAVE_SAMPLE_FTRACE_DIRECT
200	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
201	select HAVE_STACKPROTECTOR
202	select HAVE_SYSCALL_TRACEPOINTS
203	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
204	select IRQ_DOMAIN
205	select IRQ_FORCED_THREADING
206	select KASAN_VMALLOC if KASAN
207	select LOCK_MM_AND_FIND_VMA
208	select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU
209	select MODULES_USE_ELF_RELA if MODULES
210	select OF
211	select OF_EARLY_FLATTREE
212	select OF_IRQ
213	select PCI_DOMAINS_GENERIC if PCI
214	select PCI_ECAM if (ACPI && PCI)
215	select PCI_MSI if PCI
216	select RELOCATABLE if !MMU && !PHYS_RAM_BASE_FIXED
217	select RISCV_ALTERNATIVE if !XIP_KERNEL
218	select RISCV_APLIC
219	select RISCV_IMSIC
220	select RISCV_INTC
221	select RISCV_TIMER if RISCV_SBI
222	select SIFIVE_PLIC
223	select SPARSE_IRQ
224	select SYSCTL_EXCEPTION_TRACE
225	select THREAD_INFO_IN_TASK
226	select TRACE_IRQFLAGS_SUPPORT
227	select UACCESS_MEMCPY if !MMU
228	select VDSO_GETRANDOM if HAVE_GENERIC_VDSO
229	select USER_STACKTRACE_SUPPORT
230	select ZONE_DMA32 if 64BIT
231
232config RUSTC_SUPPORTS_RISCV
233	def_bool y
234	depends on 64BIT
235	# Shadow call stack requires rustc version 1.82+ due to use of the
236	# -Zsanitizer=shadow-call-stack flag.
237	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
238
239config CLANG_SUPPORTS_DYNAMIC_FTRACE
240	def_bool CC_IS_CLANG
241	# https://github.com/ClangBuiltLinux/linux/issues/1817
242	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
243
244config GCC_SUPPORTS_DYNAMIC_FTRACE
245	def_bool CC_IS_GCC
246	depends on $(cc-option,-fpatchable-function-entry=8)
247	depends on CC_HAS_MIN_FUNCTION_ALIGNMENT || !RISCV_ISA_C
248
249config HAVE_SHADOW_CALL_STACK
250	def_bool $(cc-option,-fsanitize=shadow-call-stack)
251	# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
252	depends on $(ld-option,--no-relax-gp)
253
254config RISCV_USE_LINKER_RELAXATION
255	def_bool y
256	# https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
257	depends on !LD_IS_LLD || LLD_VERSION >= 150000
258
259# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6
260config ARCH_HAS_BROKEN_DWARF5
261	def_bool y
262	depends on RISCV_USE_LINKER_RELAXATION
263	# https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a
264	depends on AS_IS_LLVM && AS_VERSION < 180000
265	# https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77
266	depends on LD_IS_LLD && LLD_VERSION < 180000
267
268config ARCH_MMAP_RND_BITS_MIN
269	default 18 if 64BIT
270	default 8
271
272config ARCH_MMAP_RND_COMPAT_BITS_MIN
273	default 8
274
275# max bits determined by the following formula:
276#  VA_BITS - PAGE_SHIFT - 3
277config ARCH_MMAP_RND_BITS_MAX
278	default 24 if 64BIT # SV39 based
279	default 17
280
281config ARCH_MMAP_RND_COMPAT_BITS_MAX
282	default 17
283
284# set if we run in machine mode, cleared if we run in supervisor mode
285config RISCV_M_MODE
286	bool "Build a kernel that runs in machine mode"
287	depends on !MMU
288	default y
289	help
290	  Select this option if you want to run the kernel in M-mode,
291	  without the assistance of any other firmware.
292
293# set if we are running in S-mode and can use SBI calls
294config RISCV_SBI
295	bool
296	depends on !RISCV_M_MODE
297	default y
298
299config MMU
300	bool "MMU-based Paged Memory Management Support"
301	default y
302	help
303	  Select if you want MMU-based virtualised addressing space
304	  support by paged memory management. If unsure, say 'Y'.
305
306config KASAN_SHADOW_OFFSET
307	hex
308	depends on KASAN_GENERIC
309	default 0xdfffffff00000000 if 64BIT
310	default 0xffffffff if 32BIT
311
312config ARCH_FLATMEM_ENABLE
313	def_bool !NUMA
314
315config ARCH_SPARSEMEM_ENABLE
316	def_bool y
317	depends on MMU
318	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
319	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
320
321config ARCH_SELECT_MEMORY_MODEL
322	def_bool ARCH_SPARSEMEM_ENABLE
323
324config ARCH_SUPPORTS_UPROBES
325	def_bool y
326
327config STACKTRACE_SUPPORT
328	def_bool y
329
330config GENERIC_BUG
331	def_bool y
332	depends on BUG
333	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
334
335config GENERIC_BUG_RELATIVE_POINTERS
336	bool
337
338config GENERIC_CALIBRATE_DELAY
339	def_bool y
340
341config GENERIC_CSUM
342	def_bool y
343
344config GENERIC_HWEIGHT
345	def_bool y
346
347config FIX_EARLYCON_MEM
348	def_bool MMU
349
350config ILLEGAL_POINTER_VALUE
351	hex
352	default 0 if 32BIT
353	default 0xdead000000000000 if 64BIT
354
355config PGTABLE_LEVELS
356	int
357	default 5 if 64BIT
358	default 2
359
360config LOCKDEP_SUPPORT
361	def_bool y
362
363config RISCV_DMA_NONCOHERENT
364	bool
365	select ARCH_HAS_DMA_PREP_COHERENT
366	select ARCH_HAS_SETUP_DMA_OPS
367	select ARCH_HAS_SYNC_DMA_FOR_CPU
368	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
369	select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB
370
371config RISCV_NONSTANDARD_CACHE_OPS
372	bool
373	help
374	  This enables function pointer support for non-standard noncoherent
375	  systems to handle cache management.
376
377config AS_HAS_INSN
378	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
379
380config AS_HAS_OPTION_ARCH
381	# https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
382	def_bool y
383	depends on $(as-instr, .option arch$(comma) +m)
384
385source "arch/riscv/Kconfig.socs"
386source "arch/riscv/Kconfig.errata"
387
388menu "Platform type"
389
390config NONPORTABLE
391	bool "Allow configurations that result in non-portable kernels"
392	help
393	  RISC-V kernel binaries are compatible between all known systems
394	  whenever possible, but there are some use cases that can only be
395	  satisfied by configurations that result in kernel binaries that are
396	  not portable between systems.
397
398	  Selecting N does not guarantee kernels will be portable to all known
399	  systems.  Selecting any of the options guarded by NONPORTABLE will
400	  result in kernel binaries that are unlikely to be portable between
401	  systems.
402
403	  If unsure, say N.
404
405choice
406	prompt "Base ISA"
407	default ARCH_RV64I
408	help
409	  This selects the base ISA that this kernel will target and must match
410	  the target platform.
411
412config ARCH_RV32I
413	bool "RV32I"
414	depends on NONPORTABLE
415	select 32BIT
416	select GENERIC_LIB_ASHLDI3
417	select GENERIC_LIB_ASHRDI3
418	select GENERIC_LIB_LSHRDI3
419	select GENERIC_LIB_UCMPDI2
420
421config ARCH_RV64I
422	bool "RV64I"
423	select 64BIT
424	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
425	select SWIOTLB if MMU
426
427endchoice
428
429# We must be able to map all physical memory into the kernel, but the compiler
430# is still a bit more efficient when generating code if it's setup in a manner
431# such that it can only map 2GiB of memory.
432choice
433	prompt "Kernel Code Model"
434	default CMODEL_MEDLOW if 32BIT
435	default CMODEL_MEDANY if 64BIT
436
437	config CMODEL_MEDLOW
438		bool "medium low code model"
439	config CMODEL_MEDANY
440		bool "medium any code model"
441endchoice
442
443config MODULE_SECTIONS
444	bool
445	select HAVE_MOD_ARCH_SPECIFIC
446
447config SMP
448	bool "Symmetric Multi-Processing"
449	help
450	  This enables support for systems with more than one CPU.  If
451	  you say N here, the kernel will run on single and
452	  multiprocessor machines, but will use only one CPU of a
453	  multiprocessor machine. If you say Y here, the kernel will run
454	  on many, but not all, single processor machines. On a single
455	  processor machine, the kernel will run faster if you say N
456	  here.
457
458	  If you don't know what to do here, say N.
459
460config SCHED_MC
461	bool "Multi-core scheduler support"
462	depends on SMP
463	help
464	  Multi-core scheduler support improves the CPU scheduler's decision
465	  making when dealing with multi-core CPU chips at a cost of slightly
466	  increased overhead in some places. If unsure say N here.
467
468config NR_CPUS
469	int "Maximum number of CPUs (2-512)"
470	depends on SMP
471	range 2 512 if !RISCV_SBI_V01
472	range 2 32 if RISCV_SBI_V01 && 32BIT
473	range 2 64 if RISCV_SBI_V01 && 64BIT
474	default "32" if 32BIT
475	default "64" if 64BIT
476
477config HOTPLUG_CPU
478	bool "Support for hot-pluggable CPUs"
479	depends on SMP
480	select GENERIC_IRQ_MIGRATION
481	help
482
483	  Say Y here to experiment with turning CPUs off and on.  CPUs
484	  can be controlled through /sys/devices/system/cpu.
485
486	  Say N if you want to disable CPU hotplug.
487
488choice
489	prompt "CPU Tuning"
490	default TUNE_GENERIC
491
492config TUNE_GENERIC
493	bool "generic"
494
495endchoice
496
497# Common NUMA Features
498config NUMA
499	bool "NUMA Memory Allocation and Scheduler Support"
500	depends on SMP && MMU
501	select ARCH_SUPPORTS_NUMA_BALANCING
502	select GENERIC_ARCH_NUMA
503	select HAVE_SETUP_PER_CPU_AREA
504	select NEED_PER_CPU_EMBED_FIRST_CHUNK
505	select NEED_PER_CPU_PAGE_FIRST_CHUNK
506	select OF_NUMA
507	select USE_PERCPU_NUMA_NODE_ID
508	help
509	  Enable NUMA (Non-Uniform Memory Access) support.
510
511	  The kernel will try to allocate memory used by a CPU on the
512	  local memory of the CPU and add some more NUMA awareness to the kernel.
513
514config NODES_SHIFT
515	int "Maximum NUMA Nodes (as a power of 2)"
516	range 1 10
517	default "2"
518	depends on NUMA
519	help
520	  Specify the maximum number of NUMA Nodes available on the target
521	  system.  Increases memory reserved to accommodate various tables.
522
523choice
524	prompt "RISC-V spinlock type"
525	default RISCV_COMBO_SPINLOCKS
526
527config RISCV_TICKET_SPINLOCKS
528	bool "Using ticket spinlock"
529
530config RISCV_QUEUED_SPINLOCKS
531	bool "Using queued spinlock"
532	depends on SMP && MMU && NONPORTABLE
533	select ARCH_USE_QUEUED_SPINLOCKS
534	help
535	  The queued spinlock implementation requires the forward progress
536	  guarantee of cmpxchg()/xchg() atomic operations: CAS with Zabha or
537	  LR/SC with Ziccrse provide such guarantee.
538
539	  Select this if and only if Zabha or Ziccrse is available on your
540	  platform, RISCV_QUEUED_SPINLOCKS must not be selected for platforms
541	  without one of those extensions.
542
543	  If unsure, select RISCV_COMBO_SPINLOCKS, which will use qspinlocks
544	  when supported and otherwise ticket spinlocks.
545
546config RISCV_COMBO_SPINLOCKS
547	bool "Using combo spinlock"
548	depends on SMP && MMU
549	select ARCH_USE_QUEUED_SPINLOCKS
550	help
551	  Embed both queued spinlock and ticket lock so that the spinlock
552	  implementation can be chosen at runtime.
553
554endchoice
555
556config RISCV_ALTERNATIVE
557	bool
558	depends on !XIP_KERNEL
559	help
560	  This Kconfig allows the kernel to automatically patch the
561	  erratum or cpufeature required by the execution platform at run
562	  time. The code patching overhead is minimal, as it's only done
563	  once at boot and once on each module load.
564
565config RISCV_ALTERNATIVE_EARLY
566	bool
567	depends on RISCV_ALTERNATIVE
568	help
569	  Allows early patching of the kernel for special errata
570
571config RISCV_ISA_C
572	bool "Emit compressed instructions when building Linux"
573	default y
574	help
575	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
576	  when building Linux, which results in compressed instructions in the
577	  Linux binary. This option produces a kernel that will not run on
578	  systems that do not support compressed instructions.
579
580	  If you don't know what to do here, say Y.
581
582config RISCV_ISA_SUPM
583	bool "Supm extension for userspace pointer masking"
584	depends on 64BIT
585	default y
586	help
587	  Add support for pointer masking in userspace (Supm) when the
588	  underlying hardware extension (Smnpm or Ssnpm) is detected at boot.
589
590	  If this option is disabled, userspace will be unable to use
591	  the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API.
592
593config RISCV_ISA_SVNAPOT
594	bool "Svnapot extension support for supervisor mode NAPOT pages"
595	depends on 64BIT && MMU
596	depends on RISCV_ALTERNATIVE
597	default y
598	help
599	  Enable support for the Svnapot ISA-extension when it is detected
600	  at boot.
601
602	  The Svnapot extension is used to mark contiguous PTEs as a range
603	  of contiguous virtual-to-physical translations for a naturally
604	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
605	  size. When HUGETLBFS is also selected this option unconditionally
606	  allocates some memory for each NAPOT page size supported by the kernel.
607	  When optimizing for low memory consumption and for platforms without
608	  the Svnapot extension, it may be better to say N here.
609
610	  If you don't know what to do here, say Y.
611
612config RISCV_ISA_SVPBMT
613	bool "Svpbmt extension support for supervisor mode page-based memory types"
614	depends on 64BIT && MMU
615	depends on RISCV_ALTERNATIVE
616	default y
617	help
618	   Add support for the Svpbmt ISA-extension (Supervisor-mode:
619	   page-based memory types) in the kernel when it is detected at boot.
620
621	   The memory type for a page contains a combination of attributes
622	   that indicate the cacheability, idempotency, and ordering
623	   properties for access to that page.
624
625	   The Svpbmt extension is only available on 64-bit cpus.
626
627	   If you don't know what to do here, say Y.
628
629config TOOLCHAIN_HAS_V
630	bool
631	default y
632	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv)
633	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv)
634	depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800
635	depends on AS_HAS_OPTION_ARCH
636
637config RISCV_ISA_V
638	bool "Vector extension support"
639	depends on TOOLCHAIN_HAS_V
640	depends on FPU
641	select DYNAMIC_SIGFRAME
642	default y
643	help
644	  Add support for the Vector extension when it is detected at boot.
645	  When this option is disabled, neither the kernel nor userspace may
646	  use vector procedures.
647
648	  If you don't know what to do here, say Y.
649
650config RISCV_ISA_V_DEFAULT_ENABLE
651	bool "Enable userspace Vector by default"
652	depends on RISCV_ISA_V
653	default y
654	help
655	  Say Y here if you want to enable Vector in userspace by default.
656	  Otherwise, userspace has to make explicit prctl() call to enable
657	  Vector, or enable it via the sysctl interface.
658
659	  If you don't know what to do here, say Y.
660
661config RISCV_ISA_V_UCOPY_THRESHOLD
662	int "Threshold size for vectorized user copies"
663	depends on RISCV_ISA_V
664	default 768
665	help
666	  Prefer using vectorized copy_to_user()/copy_from_user() when the
667	  workload size exceeds this value.
668
669config RISCV_ISA_V_PREEMPTIVE
670	bool "Run kernel-mode Vector with kernel preemption"
671	depends on PREEMPTION
672	depends on RISCV_ISA_V
673	default y
674	help
675	  Usually, in-kernel SIMD routines are run with preemption disabled.
676	  Functions which invoke long running SIMD thus must yield the core's
677	  vector unit to prevent blocking other tasks for too long.
678
679	  This config allows the kernel to run SIMD without explicitly disabling
680	  preemption. Enabling this config will result in higher memory consumption
681	  due to the allocation of per-task's kernel Vector context.
682
683config RISCV_ISA_ZAWRS
684	bool "Zawrs extension support for more efficient busy waiting"
685	depends on RISCV_ALTERNATIVE
686	default y
687	help
688	  The Zawrs extension defines instructions to be used in polling loops
689	  which allow a hart to enter a low-power state or to trap to the
690	  hypervisor while waiting on a store to a memory location. Enable the
691	  use of these instructions in the kernel when the Zawrs extension is
692	  detected at boot.
693
694config TOOLCHAIN_HAS_ZABHA
695	bool
696	default y
697	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zabha)
698	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zabha)
699	depends on AS_HAS_OPTION_ARCH
700
701config RISCV_ISA_ZABHA
702	bool "Zabha extension support for atomic byte/halfword operations"
703	depends on TOOLCHAIN_HAS_ZABHA
704	depends on RISCV_ALTERNATIVE
705	default y
706	help
707	  Enable the use of the Zabha ISA-extension to implement kernel
708	  byte/halfword atomic memory operations when it is detected at boot.
709
710	  If you don't know what to do here, say Y.
711
712config TOOLCHAIN_HAS_ZACAS
713	bool
714	default y
715	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas)
716	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas)
717	depends on AS_HAS_OPTION_ARCH
718
719config RISCV_ISA_ZACAS
720	bool "Zacas extension support for atomic CAS"
721	depends on TOOLCHAIN_HAS_ZACAS
722	depends on RISCV_ALTERNATIVE
723	default y
724	help
725	  Enable the use of the Zacas ISA-extension to implement kernel atomic
726	  cmpxchg operations when it is detected at boot.
727
728	  If you don't know what to do here, say Y.
729
730config TOOLCHAIN_HAS_ZBB
731	bool
732	default y
733	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
734	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
735	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
736	depends on AS_HAS_OPTION_ARCH
737
738# This symbol indicates that the toolchain supports all v1.0 vector crypto
739# extensions, including Zvk*, Zvbb, and Zvbc.  LLVM added all of these at once.
740# binutils added all except Zvkb, then added Zvkb.  So we just check for Zvkb.
741config TOOLCHAIN_HAS_VECTOR_CRYPTO
742	def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb)
743	depends on AS_HAS_OPTION_ARCH
744
745config TOOLCHAIN_HAS_ZBA
746	bool
747	default y
748	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zba)
749	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zba)
750	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
751	depends on AS_HAS_OPTION_ARCH
752
753config RISCV_ISA_ZBA
754	bool "Zba extension support for bit manipulation instructions"
755	default y
756	help
757	   Add support for enabling optimisations in the kernel when the Zba
758	   extension is detected at boot.
759
760	   The Zba extension provides instructions to accelerate the generation
761	   of addresses that index into arrays of basic data types.
762
763	   If you don't know what to do here, say Y.
764
765config RISCV_ISA_ZBB
766	bool "Zbb extension support for bit manipulation instructions"
767	depends on RISCV_ALTERNATIVE
768	default y
769	help
770	   Add support for enabling optimisations in the kernel when the
771	   Zbb extension is detected at boot. Some optimisations may
772	   additionally depend on toolchain support for Zbb.
773
774	   The Zbb extension provides instructions to accelerate a number
775	   of bit-specific operations (count bit population, sign extending,
776	   bitrotation, etc).
777
778	   If you don't know what to do here, say Y.
779
780config TOOLCHAIN_HAS_ZBC
781	bool
782	default y
783	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc)
784	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc)
785	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
786	depends on AS_HAS_OPTION_ARCH
787
788config RISCV_ISA_ZBC
789	bool "Zbc extension support for carry-less multiplication instructions"
790	depends on TOOLCHAIN_HAS_ZBC
791	depends on MMU
792	depends on RISCV_ALTERNATIVE
793	default y
794	help
795	   Adds support to dynamically detect the presence of the Zbc
796	   extension (carry-less multiplication) and enable its usage.
797
798	   The Zbc extension could accelerate CRC (cyclic redundancy check)
799	   calculations.
800
801	   If you don't know what to do here, say Y.
802
803config TOOLCHAIN_HAS_ZBKB
804	bool
805	default y
806	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbkb)
807	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbkb)
808	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
809	depends on AS_HAS_OPTION_ARCH
810
811config RISCV_ISA_ZBKB
812	bool "Zbkb extension support for bit manipulation instructions"
813	depends on TOOLCHAIN_HAS_ZBKB
814	depends on RISCV_ALTERNATIVE
815	default y
816	help
817	   Adds support to dynamically detect the presence of the ZBKB
818	   extension (bit manipulation for cryptography) and enable its usage.
819
820	   The Zbkb extension provides instructions to accelerate a number
821	   of common cryptography operations (pack, zip, etc).
822
823	   If you don't know what to do here, say Y.
824
825config RISCV_ISA_ZICBOM
826	bool "Zicbom extension support for non-coherent DMA operation"
827	depends on MMU
828	depends on RISCV_ALTERNATIVE
829	default y
830	select RISCV_DMA_NONCOHERENT
831	select DMA_DIRECT_REMAP
832	help
833	   Add support for the Zicbom extension (Cache Block Management
834	   Operations) and enable its use in the kernel when it is detected
835	   at boot.
836
837	   The Zicbom extension can be used to handle for example
838	   non-coherent DMA support on devices that need it.
839
840	   If you don't know what to do here, say Y.
841
842config RISCV_ISA_ZICBOZ
843	bool "Zicboz extension support for faster zeroing of memory"
844	depends on RISCV_ALTERNATIVE
845	default y
846	help
847	   Enable the use of the Zicboz extension (cbo.zero instruction)
848	   in the kernel when it is detected at boot.
849
850	   The Zicboz extension is used for faster zeroing of memory.
851
852	   If you don't know what to do here, say Y.
853
854config RISCV_ISA_ZICBOP
855	bool "Zicbop extension support for cache block prefetch"
856	depends on MMU
857	depends on RISCV_ALTERNATIVE
858	default y
859	help
860	  Adds support to dynamically detect the presence of the ZICBOP
861	  extension (Cache Block Prefetch Operations) and enable its
862	  usage.
863
864	  The Zicbop extension can be used to prefetch cache blocks for
865	  read/write fetch.
866
867	  If you don't know what to do here, say Y.
868
869config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
870	def_bool y
871	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
872	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
873	depends on AS_IS_GNU && AS_VERSION >= 23600
874	help
875	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
876	  20191213 version, which moves some instructions from the I extension to
877	  the Zicsr and Zifencei extensions. This requires explicitly specifying
878	  Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
879	  and Zifencei are supported in binutils from version 2.36 onwards.
880	  To make life easier, and avoid forcing toolchains that default to a
881	  newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
882	  For clang < 17 or GCC < 11.3.0, for which this is not possible or need
883	  special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
884
885config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
886	def_bool y
887	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
888	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
889	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671
890	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300)
891	help
892	  Certain versions of clang and GCC do not support zicsr and zifencei via
893	  -march. This option causes an older ISA spec compatible with these older
894	  versions of clang and GCC to be passed to GAS, which has the same result
895	  as passing zicsr and zifencei to -march.
896
897config FPU
898	bool "FPU support"
899	default y
900	help
901	  Add support for floating point operations when an FPU is detected at
902	  boot. When this option is disabled, neither the kernel nor userspace
903	  may use the floating point unit.
904
905	  If you don't know what to do here, say Y.
906
907config IRQ_STACKS
908	bool "Independent irq & softirq stacks" if EXPERT
909	default y
910	select HAVE_IRQ_EXIT_ON_IRQ_STACK
911	select HAVE_SOFTIRQ_ON_OWN_STACK
912	help
913	  Add independent irq & softirq stacks for percpu to prevent kernel stack
914	  overflows. We may save some memory footprint by disabling IRQ_STACKS.
915
916config THREAD_SIZE_ORDER
917	int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT
918	range 0 4
919	default 1 if 32BIT
920	default 2
921	help
922	  Specify the Pages of thread stack size (from 4KB to 64KB), which also
923	  affects irq stack size, which is equal to thread stack size.
924
925config RISCV_MISALIGNED
926	bool
927	help
928	  Embed support for detecting and emulating misaligned
929	  scalar or vector loads and stores.
930
931config RISCV_SCALAR_MISALIGNED
932	bool
933	select RISCV_MISALIGNED
934	select SYSCTL_ARCH_UNALIGN_ALLOW
935	help
936	  Embed support for emulating misaligned loads and stores.
937
938config RISCV_VECTOR_MISALIGNED
939	bool
940	select RISCV_MISALIGNED
941	depends on RISCV_ISA_V
942	help
943	  Enable detecting support for vector misaligned loads and stores.
944
945choice
946	prompt "Unaligned Accesses Support"
947	default RISCV_PROBE_UNALIGNED_ACCESS
948	help
949	  This determines the level of support for unaligned accesses. This
950	  information is used by the kernel to perform optimizations. It is also
951	  exposed to user space via the hwprobe syscall. The hardware will be
952	  probed at boot by default.
953
954config RISCV_PROBE_UNALIGNED_ACCESS
955	bool "Probe for hardware unaligned access support"
956	select RISCV_SCALAR_MISALIGNED
957	help
958	  During boot, the kernel will run a series of tests to determine the
959	  speed of unaligned accesses. This probing will dynamically determine
960	  the speed of unaligned accesses on the underlying system. If unaligned
961	  memory accesses trap into the kernel as they are not supported by the
962	  system, the kernel will emulate the unaligned accesses to preserve the
963	  UABI.
964
965config RISCV_EMULATED_UNALIGNED_ACCESS
966	bool "Emulate unaligned access where system support is missing"
967	select RISCV_SCALAR_MISALIGNED
968	help
969	  If unaligned memory accesses trap into the kernel as they are not
970	  supported by the system, the kernel will emulate the unaligned
971	  accesses to preserve the UABI. When the underlying system does support
972	  unaligned accesses, the unaligned accesses are assumed to be slow.
973
974config RISCV_SLOW_UNALIGNED_ACCESS
975	bool "Assume the system supports slow unaligned memory accesses"
976	depends on NONPORTABLE
977	help
978	  Assume that the system supports slow unaligned memory accesses. The
979	  kernel and userspace programs may not be able to run at all on systems
980	  that do not support unaligned memory accesses.
981
982config RISCV_EFFICIENT_UNALIGNED_ACCESS
983	bool "Assume the system supports fast unaligned memory accesses"
984	depends on NONPORTABLE
985	select DCACHE_WORD_ACCESS if MMU
986	select HAVE_EFFICIENT_UNALIGNED_ACCESS
987	help
988	  Assume that the system supports fast unaligned memory accesses. When
989	  enabled, this option improves the performance of the kernel on such
990	  systems. However, the kernel and userspace programs will run much more
991	  slowly, or will not be able to run at all, on systems that do not
992	  support efficient unaligned memory accesses.
993
994endchoice
995
996choice
997	prompt "Vector unaligned Accesses Support"
998	depends on RISCV_ISA_V
999	default RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
1000	help
1001	  This determines the level of support for vector unaligned accesses. This
1002	  information is used by the kernel to perform optimizations. It is also
1003	  exposed to user space via the hwprobe syscall. The hardware will be
1004	  probed at boot by default.
1005
1006config RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
1007	bool "Probe speed of vector unaligned accesses"
1008	select RISCV_VECTOR_MISALIGNED
1009	depends on RISCV_ISA_V
1010	help
1011	  During boot, the kernel will run a series of tests to determine the
1012	  speed of vector unaligned accesses if they are supported. This probing
1013	  will dynamically determine the speed of vector unaligned accesses on
1014	  the underlying system if they are supported.
1015
1016config RISCV_SLOW_VECTOR_UNALIGNED_ACCESS
1017	bool "Assume the system supports slow vector unaligned memory accesses"
1018	depends on NONPORTABLE
1019	help
1020	  Assume that the system supports slow vector unaligned memory accesses. The
1021	  kernel and userspace programs may not be able to run at all on systems
1022	  that do not support unaligned memory accesses.
1023
1024config RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS
1025	bool "Assume the system supports fast vector unaligned memory accesses"
1026	depends on NONPORTABLE
1027	help
1028	  Assume that the system supports fast vector unaligned memory accesses. When
1029	  enabled, this option improves the performance of the kernel on such
1030	  systems. However, the kernel and userspace programs will run much more
1031	  slowly, or will not be able to run at all, on systems that do not
1032	  support efficient unaligned memory accesses.
1033
1034endchoice
1035
1036source "arch/riscv/Kconfig.vendor"
1037
1038endmenu # "Platform type"
1039
1040menu "Kernel features"
1041
1042source "kernel/Kconfig.hz"
1043
1044config RISCV_SBI_V01
1045	bool "SBI v0.1 support"
1046	depends on RISCV_SBI
1047	help
1048	  This config allows kernel to use SBI v0.1 APIs. This will be
1049	  deprecated in future once legacy M-mode software are no longer in use.
1050
1051config RISCV_BOOT_SPINWAIT
1052	bool "Spinwait booting method"
1053	depends on SMP
1054	default y if RISCV_SBI_V01 || RISCV_M_MODE
1055	help
1056	  This enables support for booting Linux via spinwait method. In the
1057	  spinwait method, all cores randomly jump to Linux. One of the cores
1058	  gets chosen via lottery and all other keep spinning on a percpu
1059	  variable. This method cannot support CPU hotplug and sparse hartid
1060	  scheme. It should be only enabled for M-mode Linux or platforms relying
1061	  on older firmware without SBI HSM extension. All other platforms should
1062	  rely on ordered booting via SBI HSM extension which gets chosen
1063	  dynamically at runtime if the firmware supports it.
1064
1065	  Since spinwait is incompatible with sparse hart IDs, it requires
1066	  NR_CPUS be large enough to contain the physical hart ID of the first
1067	  hart to enter Linux.
1068
1069	  If unsure what to do here, say N.
1070
1071config ARCH_SUPPORTS_KEXEC
1072	def_bool y
1073
1074config ARCH_SELECTS_KEXEC
1075	def_bool y
1076	depends on KEXEC
1077	select HOTPLUG_CPU if SMP
1078
1079config ARCH_SUPPORTS_KEXEC_FILE
1080	def_bool 64BIT
1081
1082config ARCH_SELECTS_KEXEC_FILE
1083	def_bool y
1084	depends on KEXEC_FILE
1085	select HAVE_IMA_KEXEC if IMA
1086	select KEXEC_ELF
1087
1088config ARCH_SUPPORTS_KEXEC_PURGATORY
1089	def_bool ARCH_SUPPORTS_KEXEC_FILE
1090
1091config ARCH_SUPPORTS_CRASH_DUMP
1092	def_bool y
1093
1094config ARCH_DEFAULT_CRASH_DUMP
1095	def_bool y
1096
1097config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1098	def_bool CRASH_RESERVE
1099
1100config COMPAT
1101	bool "Kernel support for 32-bit U-mode"
1102	default 64BIT
1103	depends on 64BIT && MMU
1104	help
1105	  This option enables support for a 32-bit U-mode running under a 64-bit
1106	  kernel at S-mode. riscv32-specific components such as system calls,
1107	  the user helper functions (vdso), signal rt_frame functions and the
1108	  ptrace interface are handled appropriately by the kernel.
1109
1110	  If you want to execute 32-bit userspace applications, say Y.
1111
1112config PARAVIRT
1113	bool "Enable paravirtualization code"
1114	depends on RISCV_SBI
1115	help
1116	  This changes the kernel so it can modify itself when it is run
1117	  under a hypervisor, potentially improving performance significantly
1118	  over full virtualization.
1119
1120config PARAVIRT_TIME_ACCOUNTING
1121	bool "Paravirtual steal time accounting"
1122	depends on PARAVIRT
1123	help
1124	  Select this option to enable fine granularity task steal time
1125	  accounting. Time spent executing other tasks in parallel with
1126	  the current vCPU is discounted from the vCPU power. To account for
1127	  that, there can be a small performance impact.
1128
1129	  If in doubt, say N here.
1130
1131config RELOCATABLE
1132	bool "Build a relocatable kernel"
1133	depends on !XIP_KERNEL
1134	select MODULE_SECTIONS if MODULES
1135	select ARCH_VMLINUX_NEEDS_RELOCS
1136	help
1137          This builds a kernel as a Position Independent Executable (PIE),
1138          which retains all relocation metadata required to relocate the
1139          kernel binary at runtime to a different virtual address than the
1140          address it was linked at.
1141          Since RISCV uses the RELA relocation format, this requires a
1142          relocation pass at runtime even if the kernel is loaded at the
1143          same address it was linked at.
1144
1145          If unsure, say N.
1146
1147config RANDOMIZE_BASE
1148        bool "Randomize the address of the kernel image"
1149        select RELOCATABLE
1150        depends on MMU && 64BIT && !XIP_KERNEL
1151        help
1152          Randomizes the virtual address at which the kernel image is
1153          loaded, as a security feature that deters exploit attempts
1154          relying on knowledge of the location of kernel internals.
1155
1156          It is the bootloader's job to provide entropy, by passing a
1157          random u64 value in /chosen/kaslr-seed at kernel entry.
1158
1159          When booting via the UEFI stub, it will invoke the firmware's
1160          EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1161          to the kernel proper. In addition, it will randomise the physical
1162          location of the kernel Image as well.
1163
1164          If unsure, say N.
1165
1166endmenu # "Kernel features"
1167
1168menu "Boot options"
1169
1170config CMDLINE
1171	string "Built-in kernel command line"
1172	help
1173	  For most platforms, the arguments for the kernel's command line
1174	  are provided at run-time, during boot. However, there are cases
1175	  where either no arguments are being provided or the provided
1176	  arguments are insufficient or even invalid.
1177
1178	  When that occurs, it is possible to define a built-in command
1179	  line here and choose how the kernel should use it later on.
1180
1181choice
1182	prompt "Built-in command line usage"
1183	depends on CMDLINE != ""
1184	default CMDLINE_FALLBACK
1185	help
1186	  Choose how the kernel will handle the provided built-in command
1187	  line.
1188
1189config CMDLINE_FALLBACK
1190	bool "Use bootloader kernel arguments if available"
1191	help
1192	  Use the built-in command line as fallback in case we get nothing
1193	  during boot. This is the default behaviour.
1194
1195config CMDLINE_EXTEND
1196	bool "Extend bootloader kernel arguments"
1197	help
1198	  The built-in command line will be appended to the command-
1199	  line arguments provided during boot. This is useful in
1200	  cases where the provided arguments are insufficient and
1201	  you don't want to or cannot modify them.
1202
1203config CMDLINE_FORCE
1204	bool "Always use the default kernel command string"
1205	help
1206	  Always use the built-in command line, even if we get one during
1207	  boot. This is useful in case you need to override the provided
1208	  command line on systems where you don't have or want control
1209	  over it.
1210
1211endchoice
1212
1213config EFI_STUB
1214	bool
1215
1216config EFI
1217	bool "UEFI runtime support"
1218	depends on OF && !XIP_KERNEL
1219	depends on MMU
1220	default y
1221	select ARCH_SUPPORTS_ACPI if 64BIT
1222	select EFI_GENERIC_STUB
1223	select EFI_PARAMS_FROM_FDT
1224	select EFI_RUNTIME_WRAPPERS
1225	select EFI_STUB
1226	select LIBFDT
1227	select RISCV_ISA_C
1228	select UCS2_STRING
1229	help
1230	  This option provides support for runtime services provided
1231	  by UEFI firmware (such as non-volatile variables, realtime
1232	  clock, and platform reset). A UEFI stub is also provided to
1233	  allow the kernel to be booted as an EFI application. This
1234	  is only useful on systems that have UEFI firmware.
1235
1236config DMI
1237	bool "Enable support for SMBIOS (DMI) tables"
1238	depends on EFI
1239	default y
1240	help
1241	  This enables SMBIOS/DMI feature for systems.
1242
1243	  This option is only useful on systems that have UEFI firmware.
1244	  However, even with this option, the resultant kernel should
1245	  continue to boot on existing non-UEFI platforms.
1246
1247config CC_HAVE_STACKPROTECTOR_TLS
1248	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
1249
1250config STACKPROTECTOR_PER_TASK
1251	def_bool y
1252	depends on !RANDSTRUCT
1253	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
1254
1255config PHYS_RAM_BASE_FIXED
1256	bool "Explicitly specified physical RAM address"
1257	depends on NONPORTABLE
1258	default n
1259
1260config PHYS_RAM_BASE
1261	hex "Platform Physical RAM address"
1262	depends on PHYS_RAM_BASE_FIXED
1263	default "0x80000000"
1264	help
1265	  This is the physical address of RAM in the system. It has to be
1266	  explicitly specified to run early relocations of read-write data
1267	  from flash to RAM.
1268
1269config XIP_KERNEL
1270	bool "Kernel Execute-In-Place from ROM"
1271	depends on MMU && SPARSEMEM && NONPORTABLE
1272	# This prevents XIP from being enabled by all{yes,mod}config, which
1273	# fail to build since XIP doesn't support large kernels.
1274	depends on !COMPILE_TEST
1275	select PHYS_RAM_BASE_FIXED
1276	help
1277	  Execute-In-Place allows the kernel to run from non-volatile storage
1278	  directly addressable by the CPU, such as NOR flash. This saves RAM
1279	  space since the text section of the kernel is not loaded from flash
1280	  to RAM.  Read-write sections, such as the data section and stack,
1281	  are still copied to RAM.  The XIP kernel is not compressed since
1282	  it has to run directly from flash, so it will take more space to
1283	  store it.  The flash address used to link the kernel object files,
1284	  and for storing it, is configuration dependent. Therefore, if you
1285	  say Y here, you must know the proper physical address where to
1286	  store the kernel image depending on your own flash memory usage.
1287
1288	  Also note that the make target becomes "make xipImage" rather than
1289	  "make zImage" or "make Image".  The final kernel binary to put in
1290	  ROM memory will be arch/riscv/boot/xipImage.
1291
1292	  SPARSEMEM is required because the kernel text and rodata that are
1293	  flash resident are not backed by memmap, then any attempt to get
1294	  a struct page on those regions will trigger a fault.
1295
1296	  If unsure, say N.
1297
1298config XIP_PHYS_ADDR
1299	hex "XIP Kernel Physical Location"
1300	depends on XIP_KERNEL
1301	default "0x21000000"
1302	help
1303	  This is the physical address in your flash memory the kernel will
1304	  be linked for and stored to.  This address is dependent on your
1305	  own flash usage.
1306
1307config RISCV_ISA_FALLBACK
1308	bool "Permit falling back to parsing riscv,isa for extension support by default"
1309	default y
1310	help
1311	  Parsing the "riscv,isa" devicetree property has been deprecated and
1312	  replaced by a list of explicitly defined strings. For compatibility
1313	  with existing platforms, the kernel will fall back to parsing the
1314	  "riscv,isa" property if the replacements are not found.
1315
1316	  Selecting N here will result in a kernel that does not use the
1317	  fallback, unless the commandline "riscv_isa_fallback" parameter is
1318	  present.
1319
1320	  Please see the dt-binding, located at
1321	  Documentation/devicetree/bindings/riscv/extensions.yaml for details
1322	  on the replacement properties, "riscv,isa-base" and
1323	  "riscv,isa-extensions".
1324
1325config BUILTIN_DTB
1326	bool "Built-in device tree"
1327	depends on OF && NONPORTABLE
1328	select GENERIC_BUILTIN_DTB
1329	help
1330	  Build a device tree into the Linux image.
1331	  This option should be selected if no bootloader is being used.
1332	  If unsure, say N.
1333
1334
1335config BUILTIN_DTB_NAME
1336	string "Built-in device tree source"
1337	depends on BUILTIN_DTB
1338	help
1339	  DTS file path (without suffix, relative to arch/riscv/boot/dts)
1340	  for the DTS file that will be used to produce the DTB linked into the
1341	  kernel.
1342
1343endmenu # "Boot options"
1344
1345config PORTABLE
1346	bool
1347	default !NONPORTABLE
1348	select EFI
1349	select MMU
1350	select OF
1351
1352config ARCH_PROC_KCORE_TEXT
1353	def_bool y
1354
1355menu "Power management options"
1356
1357source "kernel/power/Kconfig"
1358
1359config ARCH_HIBERNATION_POSSIBLE
1360	def_bool y
1361
1362config ARCH_HIBERNATION_HEADER
1363	def_bool HIBERNATION
1364
1365config ARCH_SUSPEND_POSSIBLE
1366	def_bool y
1367
1368endmenu # "Power management options"
1369
1370menu "CPU Power Management"
1371
1372source "drivers/cpuidle/Kconfig"
1373
1374source "drivers/cpufreq/Kconfig"
1375
1376endmenu # "CPU Power Management"
1377
1378source "arch/riscv/kvm/Kconfig"
1379
1380source "drivers/acpi/Kconfig"
1381