xref: /linux/arch/riscv/Kconfig (revision a578dd095dfe8b56c167201d9aea43e47d27f807)
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_PTDUMP if MMU
46	select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU
47	select ARCH_HAS_PTE_SPECIAL
48	select ARCH_HAS_SET_DIRECT_MAP if MMU
49	select ARCH_HAS_SET_MEMORY if MMU
50	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
51	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
52	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
53	select ARCH_HAS_SYSCALL_WRAPPER
54	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
55	select ARCH_HAS_UBSAN
56	select ARCH_HAS_VDSO_ARCH_DATA if GENERIC_VDSO_DATA_STORE
57	select ARCH_KEEP_MEMBLOCK if ACPI
58	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
59	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
60	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
61	select ARCH_STACKWALK
62	select ARCH_SUPPORTS_ATOMIC_RMW
63	# clang >= 17: https://github.com/llvm/llvm-project/commit/62fa708ceb027713b386c7e0efda994f8bdc27e2
64	select ARCH_SUPPORTS_CFI_CLANG if CLANG_VERSION >= 170000
65	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
66	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
67	select ARCH_SUPPORTS_HUGETLBFS if MMU
68	# LLD >= 14: https://github.com/llvm/llvm-project/issues/50505
69	select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000
70	select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000
71	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS if 64BIT && MMU
72	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
73	select ARCH_SUPPORTS_PER_VMA_LOCK if MMU
74	select ARCH_SUPPORTS_RT
75	select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK
76	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
77	select ARCH_USE_MEMTEST
78	select ARCH_USE_QUEUED_RWLOCKS
79	select ARCH_USE_SYM_ANNOTATIONS
80	select ARCH_USES_CFI_TRAPS if CFI_CLANG
81	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
82	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
83	select ARCH_WANT_FRAME_POINTERS
84	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
85	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
86	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
87	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
88	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
89	select ARCH_WANTS_NO_INSTR
90	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
91	select ARCH_WEAK_RELEASE_ACQUIRE if ARCH_USE_QUEUED_SPINLOCKS
92	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
93	select BUILDTIME_TABLE_SORT if MMU
94	select CLINT_TIMER if RISCV_M_MODE
95	select CLONE_BACKWARDS
96	select COMMON_CLK
97	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
98	select DYNAMIC_FTRACE if FUNCTION_TRACER
99	select EDAC_SUPPORT
100	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
101	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
102	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
103	select GENERIC_ARCH_TOPOLOGY
104	select GENERIC_ATOMIC64 if !64BIT
105	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
106	select GENERIC_CPU_DEVICES
107	select GENERIC_CPU_VULNERABILITIES
108	select GENERIC_EARLY_IOREMAP
109	select GENERIC_ENTRY
110	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
111	select GENERIC_IDLE_POLL_SETUP
112	select GENERIC_IOREMAP if MMU
113	select GENERIC_IRQ_IPI if SMP
114	select GENERIC_IRQ_IPI_MUX if SMP
115	select GENERIC_IRQ_MULTI_HANDLER
116	select GENERIC_IRQ_SHOW
117	select GENERIC_IRQ_SHOW_LEVEL
118	select GENERIC_LIB_DEVMEM_IS_ALLOWED
119	select GENERIC_PENDING_IRQ if SMP
120	select GENERIC_PCI_IOMAP
121	select GENERIC_SCHED_CLOCK
122	select GENERIC_SMP_IDLE_THREAD
123	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
124	select GENERIC_VDSO_DATA_STORE if MMU
125	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
126	select HARDIRQS_SW_RESEND
127	select HAS_IOPORT if MMU
128	select HAVE_ALIGNED_STRUCT_PAGE
129	select HAVE_ARCH_AUDITSYSCALL
130	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
131	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT
132	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
133	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
134	select HAVE_ARCH_KASAN if MMU && 64BIT
135	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
136	select HAVE_ARCH_KFENCE if MMU && 64BIT
137	select HAVE_ARCH_KSTACK_ERASE
138	select HAVE_ARCH_KGDB if !XIP_KERNEL
139	select HAVE_ARCH_KGDB_QXFER_PKT
140	select HAVE_ARCH_MMAP_RND_BITS if MMU
141	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
142	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
143	select HAVE_ARCH_SECCOMP_FILTER
144	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
145	select HAVE_ARCH_TRACEHOOK
146	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
147	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if 64BIT && MMU
148	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
149	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
150	select HAVE_ASM_MODVERSIONS
151	select HAVE_CONTEXT_TRACKING_USER
152	select HAVE_DEBUG_KMEMLEAK
153	select HAVE_DMA_CONTIGUOUS if MMU
154	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE)
155	select FUNCTION_ALIGNMENT_4B if HAVE_DYNAMIC_FTRACE && RISCV_ISA_C
156	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS if HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS
157	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG)
158	select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
159	select HAVE_FTRACE_GRAPH_FUNC
160	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
161	select HAVE_FUNCTION_GRAPH_TRACER if HAVE_DYNAMIC_FTRACE_WITH_ARGS
162	select HAVE_FUNCTION_GRAPH_FREGS
163	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && HAVE_DYNAMIC_FTRACE
164	select HAVE_EBPF_JIT if MMU
165	select HAVE_GUP_FAST if MMU
166	select HAVE_FUNCTION_ARG_ACCESS_API
167	select HAVE_FUNCTION_ERROR_INJECTION
168	select HAVE_GCC_PLUGINS
169	select HAVE_GENERIC_VDSO if MMU && 64BIT
170	select HAVE_IRQ_TIME_ACCOUNTING
171	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
172	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
173	select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT
174	select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT
175	select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT
176	select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT
177	select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT
178	select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT
179	select HAVE_KPROBES if !XIP_KERNEL
180	select HAVE_KRETPROBES if !XIP_KERNEL
181	# https://github.com/ClangBuiltLinux/linux/issues/1881
182	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
183	select HAVE_MOVE_PMD
184	select HAVE_MOVE_PUD
185	select HAVE_PAGE_SIZE_4KB
186	select HAVE_PCI
187	select HAVE_PERF_EVENTS
188	select HAVE_PERF_REGS
189	select HAVE_PERF_USER_STACK_DUMP
190	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
191	select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL
192	select HAVE_REGS_AND_STACK_ACCESS_API
193	select HAVE_RETHOOK if !XIP_KERNEL
194	select HAVE_RSEQ
195	select HAVE_RUST if RUSTC_SUPPORTS_RISCV && CC_IS_CLANG
196	select HAVE_SAMPLE_FTRACE_DIRECT
197	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
198	select HAVE_STACKPROTECTOR
199	select HAVE_SYSCALL_TRACEPOINTS
200	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
201	select IRQ_DOMAIN
202	select IRQ_FORCED_THREADING
203	select KASAN_VMALLOC if KASAN
204	select LOCK_MM_AND_FIND_VMA
205	select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU
206	select MODULES_USE_ELF_RELA if MODULES
207	select OF
208	select OF_EARLY_FLATTREE
209	select OF_IRQ
210	select PCI_DOMAINS_GENERIC if PCI
211	select PCI_ECAM if (ACPI && PCI)
212	select PCI_MSI if PCI
213	select RELOCATABLE if !MMU && !PHYS_RAM_BASE_FIXED
214	select RISCV_ALTERNATIVE if !XIP_KERNEL
215	select RISCV_APLIC
216	select RISCV_IMSIC
217	select RISCV_INTC
218	select RISCV_TIMER if RISCV_SBI
219	select SIFIVE_PLIC
220	select SPARSE_IRQ
221	select SYSCTL_EXCEPTION_TRACE
222	select THREAD_INFO_IN_TASK
223	select TRACE_IRQFLAGS_SUPPORT
224	select UACCESS_MEMCPY if !MMU
225	select VDSO_GETRANDOM if HAVE_GENERIC_VDSO
226	select USER_STACKTRACE_SUPPORT
227	select ZONE_DMA32 if 64BIT
228
229config RUSTC_SUPPORTS_RISCV
230	def_bool y
231	depends on 64BIT
232	# Shadow call stack requires rustc version 1.82+ due to use of the
233	# -Zsanitizer=shadow-call-stack flag.
234	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
235
236config CLANG_SUPPORTS_DYNAMIC_FTRACE
237	def_bool CC_IS_CLANG
238	# https://github.com/ClangBuiltLinux/linux/issues/1817
239	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
240
241config GCC_SUPPORTS_DYNAMIC_FTRACE
242	def_bool CC_IS_GCC
243	depends on $(cc-option,-fpatchable-function-entry=8)
244	depends on CC_HAS_MIN_FUNCTION_ALIGNMENT || !RISCV_ISA_C
245
246config HAVE_SHADOW_CALL_STACK
247	def_bool $(cc-option,-fsanitize=shadow-call-stack)
248	# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
249	depends on $(ld-option,--no-relax-gp)
250
251config RISCV_USE_LINKER_RELAXATION
252	def_bool y
253	# https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
254	depends on !LD_IS_LLD || LLD_VERSION >= 150000
255
256# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6
257config ARCH_HAS_BROKEN_DWARF5
258	def_bool y
259	depends on RISCV_USE_LINKER_RELAXATION
260	# https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a
261	depends on AS_IS_LLVM && AS_VERSION < 180000
262	# https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77
263	depends on LD_IS_LLD && LLD_VERSION < 180000
264
265config ARCH_MMAP_RND_BITS_MIN
266	default 18 if 64BIT
267	default 8
268
269config ARCH_MMAP_RND_COMPAT_BITS_MIN
270	default 8
271
272# max bits determined by the following formula:
273#  VA_BITS - PAGE_SHIFT - 3
274config ARCH_MMAP_RND_BITS_MAX
275	default 24 if 64BIT # SV39 based
276	default 17
277
278config ARCH_MMAP_RND_COMPAT_BITS_MAX
279	default 17
280
281# set if we run in machine mode, cleared if we run in supervisor mode
282config RISCV_M_MODE
283	bool "Build a kernel that runs in machine mode"
284	depends on !MMU
285	default y
286	help
287	  Select this option if you want to run the kernel in M-mode,
288	  without the assistance of any other firmware.
289
290# set if we are running in S-mode and can use SBI calls
291config RISCV_SBI
292	bool
293	depends on !RISCV_M_MODE
294	default y
295
296config MMU
297	bool "MMU-based Paged Memory Management Support"
298	default y
299	help
300	  Select if you want MMU-based virtualised addressing space
301	  support by paged memory management. If unsure, say 'Y'.
302
303config KASAN_SHADOW_OFFSET
304	hex
305	depends on KASAN_GENERIC
306	default 0xdfffffff00000000 if 64BIT
307	default 0xffffffff if 32BIT
308
309config ARCH_FLATMEM_ENABLE
310	def_bool !NUMA
311
312config ARCH_SPARSEMEM_ENABLE
313	def_bool y
314	depends on MMU
315	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
316	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
317
318config ARCH_SELECT_MEMORY_MODEL
319	def_bool ARCH_SPARSEMEM_ENABLE
320
321config ARCH_SUPPORTS_UPROBES
322	def_bool y
323
324config STACKTRACE_SUPPORT
325	def_bool y
326
327config GENERIC_BUG
328	def_bool y
329	depends on BUG
330	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
331
332config GENERIC_BUG_RELATIVE_POINTERS
333	bool
334
335config GENERIC_CALIBRATE_DELAY
336	def_bool y
337
338config GENERIC_CSUM
339	def_bool y
340
341config GENERIC_HWEIGHT
342	def_bool y
343
344config FIX_EARLYCON_MEM
345	def_bool MMU
346
347config ILLEGAL_POINTER_VALUE
348	hex
349	default 0 if 32BIT
350	default 0xdead000000000000 if 64BIT
351
352config PGTABLE_LEVELS
353	int
354	default 5 if 64BIT
355	default 2
356
357config LOCKDEP_SUPPORT
358	def_bool y
359
360config RISCV_DMA_NONCOHERENT
361	bool
362	select ARCH_HAS_DMA_PREP_COHERENT
363	select ARCH_HAS_SETUP_DMA_OPS
364	select ARCH_HAS_SYNC_DMA_FOR_CPU
365	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
366	select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB
367
368config RISCV_NONSTANDARD_CACHE_OPS
369	bool
370	help
371	  This enables function pointer support for non-standard noncoherent
372	  systems to handle cache management.
373
374config AS_HAS_INSN
375	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
376
377config AS_HAS_OPTION_ARCH
378	# https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
379	def_bool y
380	depends on $(as-instr, .option arch$(comma) +m)
381
382source "arch/riscv/Kconfig.socs"
383source "arch/riscv/Kconfig.errata"
384
385menu "Platform type"
386
387config NONPORTABLE
388	bool "Allow configurations that result in non-portable kernels"
389	help
390	  RISC-V kernel binaries are compatible between all known systems
391	  whenever possible, but there are some use cases that can only be
392	  satisfied by configurations that result in kernel binaries that are
393	  not portable between systems.
394
395	  Selecting N does not guarantee kernels will be portable to all known
396	  systems.  Selecting any of the options guarded by NONPORTABLE will
397	  result in kernel binaries that are unlikely to be portable between
398	  systems.
399
400	  If unsure, say N.
401
402choice
403	prompt "Base ISA"
404	default ARCH_RV64I
405	help
406	  This selects the base ISA that this kernel will target and must match
407	  the target platform.
408
409config ARCH_RV32I
410	bool "RV32I"
411	depends on NONPORTABLE
412	select 32BIT
413	select GENERIC_LIB_ASHLDI3
414	select GENERIC_LIB_ASHRDI3
415	select GENERIC_LIB_LSHRDI3
416	select GENERIC_LIB_UCMPDI2
417
418config ARCH_RV64I
419	bool "RV64I"
420	select 64BIT
421	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
422	select SWIOTLB if MMU
423
424endchoice
425
426# We must be able to map all physical memory into the kernel, but the compiler
427# is still a bit more efficient when generating code if it's setup in a manner
428# such that it can only map 2GiB of memory.
429choice
430	prompt "Kernel Code Model"
431	default CMODEL_MEDLOW if 32BIT
432	default CMODEL_MEDANY if 64BIT
433
434	config CMODEL_MEDLOW
435		bool "medium low code model"
436	config CMODEL_MEDANY
437		bool "medium any code model"
438endchoice
439
440config MODULE_SECTIONS
441	bool
442	select HAVE_MOD_ARCH_SPECIFIC
443
444config SMP
445	bool "Symmetric Multi-Processing"
446	help
447	  This enables support for systems with more than one CPU.  If
448	  you say N here, the kernel will run on single and
449	  multiprocessor machines, but will use only one CPU of a
450	  multiprocessor machine. If you say Y here, the kernel will run
451	  on many, but not all, single processor machines. On a single
452	  processor machine, the kernel will run faster if you say N
453	  here.
454
455	  If you don't know what to do here, say N.
456
457config SCHED_MC
458	bool "Multi-core scheduler support"
459	depends on SMP
460	help
461	  Multi-core scheduler support improves the CPU scheduler's decision
462	  making when dealing with multi-core CPU chips at a cost of slightly
463	  increased overhead in some places. If unsure say N here.
464
465config NR_CPUS
466	int "Maximum number of CPUs (2-512)"
467	depends on SMP
468	range 2 512 if !RISCV_SBI_V01
469	range 2 32 if RISCV_SBI_V01 && 32BIT
470	range 2 64 if RISCV_SBI_V01 && 64BIT
471	default "32" if 32BIT
472	default "64" if 64BIT
473
474config HOTPLUG_CPU
475	bool "Support for hot-pluggable CPUs"
476	depends on SMP
477	select GENERIC_IRQ_MIGRATION
478	help
479
480	  Say Y here to experiment with turning CPUs off and on.  CPUs
481	  can be controlled through /sys/devices/system/cpu.
482
483	  Say N if you want to disable CPU hotplug.
484
485choice
486	prompt "CPU Tuning"
487	default TUNE_GENERIC
488
489config TUNE_GENERIC
490	bool "generic"
491
492endchoice
493
494# Common NUMA Features
495config NUMA
496	bool "NUMA Memory Allocation and Scheduler Support"
497	depends on SMP && MMU
498	select ARCH_SUPPORTS_NUMA_BALANCING
499	select GENERIC_ARCH_NUMA
500	select HAVE_SETUP_PER_CPU_AREA
501	select NEED_PER_CPU_EMBED_FIRST_CHUNK
502	select NEED_PER_CPU_PAGE_FIRST_CHUNK
503	select OF_NUMA
504	select USE_PERCPU_NUMA_NODE_ID
505	help
506	  Enable NUMA (Non-Uniform Memory Access) support.
507
508	  The kernel will try to allocate memory used by a CPU on the
509	  local memory of the CPU and add some more NUMA awareness to the kernel.
510
511config NODES_SHIFT
512	int "Maximum NUMA Nodes (as a power of 2)"
513	range 1 10
514	default "2"
515	depends on NUMA
516	help
517	  Specify the maximum number of NUMA Nodes available on the target
518	  system.  Increases memory reserved to accommodate various tables.
519
520choice
521	prompt "RISC-V spinlock type"
522	default RISCV_COMBO_SPINLOCKS
523
524config RISCV_TICKET_SPINLOCKS
525	bool "Using ticket spinlock"
526
527config RISCV_QUEUED_SPINLOCKS
528	bool "Using queued spinlock"
529	depends on SMP && MMU && NONPORTABLE
530	select ARCH_USE_QUEUED_SPINLOCKS
531	help
532	  The queued spinlock implementation requires the forward progress
533	  guarantee of cmpxchg()/xchg() atomic operations: CAS with Zabha or
534	  LR/SC with Ziccrse provide such guarantee.
535
536	  Select this if and only if Zabha or Ziccrse is available on your
537	  platform, RISCV_QUEUED_SPINLOCKS must not be selected for platforms
538	  without one of those extensions.
539
540	  If unsure, select RISCV_COMBO_SPINLOCKS, which will use qspinlocks
541	  when supported and otherwise ticket spinlocks.
542
543config RISCV_COMBO_SPINLOCKS
544	bool "Using combo spinlock"
545	depends on SMP && MMU
546	select ARCH_USE_QUEUED_SPINLOCKS
547	help
548	  Embed both queued spinlock and ticket lock so that the spinlock
549	  implementation can be chosen at runtime.
550
551endchoice
552
553config RISCV_ALTERNATIVE
554	bool
555	depends on !XIP_KERNEL
556	help
557	  This Kconfig allows the kernel to automatically patch the
558	  erratum or cpufeature required by the execution platform at run
559	  time. The code patching overhead is minimal, as it's only done
560	  once at boot and once on each module load.
561
562config RISCV_ALTERNATIVE_EARLY
563	bool
564	depends on RISCV_ALTERNATIVE
565	help
566	  Allows early patching of the kernel for special errata
567
568config RISCV_ISA_C
569	bool "Emit compressed instructions when building Linux"
570	default y
571	help
572	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
573	  when building Linux, which results in compressed instructions in the
574	  Linux binary. This option produces a kernel that will not run on
575	  systems that do not support compressed instructions.
576
577	  If you don't know what to do here, say Y.
578
579config RISCV_ISA_SUPM
580	bool "Supm extension for userspace pointer masking"
581	depends on 64BIT
582	default y
583	help
584	  Add support for pointer masking in userspace (Supm) when the
585	  underlying hardware extension (Smnpm or Ssnpm) is detected at boot.
586
587	  If this option is disabled, userspace will be unable to use
588	  the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API.
589
590config RISCV_ISA_SVNAPOT
591	bool "Svnapot extension support for supervisor mode NAPOT pages"
592	depends on 64BIT && MMU
593	depends on RISCV_ALTERNATIVE
594	default y
595	help
596	  Enable support for the Svnapot ISA-extension when it is detected
597	  at boot.
598
599	  The Svnapot extension is used to mark contiguous PTEs as a range
600	  of contiguous virtual-to-physical translations for a naturally
601	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
602	  size. When HUGETLBFS is also selected this option unconditionally
603	  allocates some memory for each NAPOT page size supported by the kernel.
604	  When optimizing for low memory consumption and for platforms without
605	  the Svnapot extension, it may be better to say N here.
606
607	  If you don't know what to do here, say Y.
608
609config RISCV_ISA_SVPBMT
610	bool "Svpbmt extension support for supervisor mode page-based memory types"
611	depends on 64BIT && MMU
612	depends on RISCV_ALTERNATIVE
613	default y
614	help
615	   Add support for the Svpbmt ISA-extension (Supervisor-mode:
616	   page-based memory types) in the kernel when it is detected at boot.
617
618	   The memory type for a page contains a combination of attributes
619	   that indicate the cacheability, idempotency, and ordering
620	   properties for access to that page.
621
622	   The Svpbmt extension is only available on 64-bit cpus.
623
624	   If you don't know what to do here, say Y.
625
626config TOOLCHAIN_HAS_V
627	bool
628	default y
629	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv)
630	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv)
631	depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800
632	depends on AS_HAS_OPTION_ARCH
633
634config RISCV_ISA_V
635	bool "Vector extension support"
636	depends on TOOLCHAIN_HAS_V
637	depends on FPU
638	select DYNAMIC_SIGFRAME
639	default y
640	help
641	  Add support for the Vector extension when it is detected at boot.
642	  When this option is disabled, neither the kernel nor userspace may
643	  use vector procedures.
644
645	  If you don't know what to do here, say Y.
646
647config RISCV_ISA_V_DEFAULT_ENABLE
648	bool "Enable userspace Vector by default"
649	depends on RISCV_ISA_V
650	default y
651	help
652	  Say Y here if you want to enable Vector in userspace by default.
653	  Otherwise, userspace has to make explicit prctl() call to enable
654	  Vector, or enable it via the sysctl interface.
655
656	  If you don't know what to do here, say Y.
657
658config RISCV_ISA_V_UCOPY_THRESHOLD
659	int "Threshold size for vectorized user copies"
660	depends on RISCV_ISA_V
661	default 768
662	help
663	  Prefer using vectorized copy_to_user()/copy_from_user() when the
664	  workload size exceeds this value.
665
666config RISCV_ISA_V_PREEMPTIVE
667	bool "Run kernel-mode Vector with kernel preemption"
668	depends on PREEMPTION
669	depends on RISCV_ISA_V
670	default y
671	help
672	  Usually, in-kernel SIMD routines are run with preemption disabled.
673	  Functions which invoke long running SIMD thus must yield the core's
674	  vector unit to prevent blocking other tasks for too long.
675
676	  This config allows the kernel to run SIMD without explicitly disabling
677	  preemption. Enabling this config will result in higher memory consumption
678	  due to the allocation of per-task's kernel Vector context.
679
680config RISCV_ISA_ZAWRS
681	bool "Zawrs extension support for more efficient busy waiting"
682	depends on RISCV_ALTERNATIVE
683	default y
684	help
685	  The Zawrs extension defines instructions to be used in polling loops
686	  which allow a hart to enter a low-power state or to trap to the
687	  hypervisor while waiting on a store to a memory location. Enable the
688	  use of these instructions in the kernel when the Zawrs extension is
689	  detected at boot.
690
691config TOOLCHAIN_HAS_ZABHA
692	bool
693	default y
694	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zabha)
695	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zabha)
696	depends on AS_HAS_OPTION_ARCH
697
698config RISCV_ISA_ZABHA
699	bool "Zabha extension support for atomic byte/halfword operations"
700	depends on TOOLCHAIN_HAS_ZABHA
701	depends on RISCV_ALTERNATIVE
702	default y
703	help
704	  Enable the use of the Zabha ISA-extension to implement kernel
705	  byte/halfword atomic memory operations when it is detected at boot.
706
707	  If you don't know what to do here, say Y.
708
709config TOOLCHAIN_HAS_ZACAS
710	bool
711	default y
712	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas)
713	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas)
714	depends on AS_HAS_OPTION_ARCH
715
716config RISCV_ISA_ZACAS
717	bool "Zacas extension support for atomic CAS"
718	depends on TOOLCHAIN_HAS_ZACAS
719	depends on RISCV_ALTERNATIVE
720	default y
721	help
722	  Enable the use of the Zacas ISA-extension to implement kernel atomic
723	  cmpxchg operations when it is detected at boot.
724
725	  If you don't know what to do here, say Y.
726
727config TOOLCHAIN_HAS_ZBB
728	bool
729	default y
730	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
731	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
732	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
733	depends on AS_HAS_OPTION_ARCH
734
735# This symbol indicates that the toolchain supports all v1.0 vector crypto
736# extensions, including Zvk*, Zvbb, and Zvbc.  LLVM added all of these at once.
737# binutils added all except Zvkb, then added Zvkb.  So we just check for Zvkb.
738config TOOLCHAIN_HAS_VECTOR_CRYPTO
739	def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb)
740	depends on AS_HAS_OPTION_ARCH
741
742config TOOLCHAIN_HAS_ZBA
743	bool
744	default y
745	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zba)
746	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zba)
747	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
748	depends on AS_HAS_OPTION_ARCH
749
750config RISCV_ISA_ZBA
751	bool "Zba extension support for bit manipulation instructions"
752	default y
753	help
754	   Add support for enabling optimisations in the kernel when the Zba
755	   extension is detected at boot.
756
757	   The Zba extension provides instructions to accelerate the generation
758	   of addresses that index into arrays of basic data types.
759
760	   If you don't know what to do here, say Y.
761
762config RISCV_ISA_ZBB
763	bool "Zbb extension support for bit manipulation instructions"
764	depends on RISCV_ALTERNATIVE
765	default y
766	help
767	   Add support for enabling optimisations in the kernel when the
768	   Zbb extension is detected at boot. Some optimisations may
769	   additionally depend on toolchain support for Zbb.
770
771	   The Zbb extension provides instructions to accelerate a number
772	   of bit-specific operations (count bit population, sign extending,
773	   bitrotation, etc).
774
775	   If you don't know what to do here, say Y.
776
777config TOOLCHAIN_HAS_ZBC
778	bool
779	default y
780	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc)
781	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc)
782	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
783	depends on AS_HAS_OPTION_ARCH
784
785config RISCV_ISA_ZBC
786	bool "Zbc extension support for carry-less multiplication instructions"
787	depends on TOOLCHAIN_HAS_ZBC
788	depends on MMU
789	depends on RISCV_ALTERNATIVE
790	default y
791	help
792	   Adds support to dynamically detect the presence of the Zbc
793	   extension (carry-less multiplication) and enable its usage.
794
795	   The Zbc extension could accelerate CRC (cyclic redundancy check)
796	   calculations.
797
798	   If you don't know what to do here, say Y.
799
800config TOOLCHAIN_HAS_ZBKB
801	bool
802	default y
803	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbkb)
804	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbkb)
805	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
806	depends on AS_HAS_OPTION_ARCH
807
808config RISCV_ISA_ZBKB
809	bool "Zbkb extension support for bit manipulation instructions"
810	depends on TOOLCHAIN_HAS_ZBKB
811	depends on RISCV_ALTERNATIVE
812	default y
813	help
814	   Adds support to dynamically detect the presence of the ZBKB
815	   extension (bit manipulation for cryptography) and enable its usage.
816
817	   The Zbkb extension provides instructions to accelerate a number
818	   of common cryptography operations (pack, zip, etc).
819
820	   If you don't know what to do here, say Y.
821
822config RISCV_ISA_ZICBOM
823	bool "Zicbom extension support for non-coherent DMA operation"
824	depends on MMU
825	depends on RISCV_ALTERNATIVE
826	default y
827	select RISCV_DMA_NONCOHERENT
828	select DMA_DIRECT_REMAP
829	help
830	   Add support for the Zicbom extension (Cache Block Management
831	   Operations) and enable its use in the kernel when it is detected
832	   at boot.
833
834	   The Zicbom extension can be used to handle for example
835	   non-coherent DMA support on devices that need it.
836
837	   If you don't know what to do here, say Y.
838
839config RISCV_ISA_ZICBOZ
840	bool "Zicboz extension support for faster zeroing of memory"
841	depends on RISCV_ALTERNATIVE
842	default y
843	help
844	   Enable the use of the Zicboz extension (cbo.zero instruction)
845	   in the kernel when it is detected at boot.
846
847	   The Zicboz extension is used for faster zeroing of memory.
848
849	   If you don't know what to do here, say Y.
850
851config RISCV_ISA_ZICBOP
852	bool "Zicbop extension support for cache block prefetch"
853	depends on MMU
854	depends on RISCV_ALTERNATIVE
855	default y
856	help
857	  Adds support to dynamically detect the presence of the ZICBOP
858	  extension (Cache Block Prefetch Operations) and enable its
859	  usage.
860
861	  The Zicbop extension can be used to prefetch cache blocks for
862	  read/write fetch.
863
864	  If you don't know what to do here, say Y.
865
866config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
867	def_bool y
868	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
869	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
870	depends on AS_IS_GNU && AS_VERSION >= 23600
871	help
872	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
873	  20191213 version, which moves some instructions from the I extension to
874	  the Zicsr and Zifencei extensions. This requires explicitly specifying
875	  Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
876	  and Zifencei are supported in binutils from version 2.36 onwards.
877	  To make life easier, and avoid forcing toolchains that default to a
878	  newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
879	  For clang < 17 or GCC < 11.3.0, for which this is not possible or need
880	  special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
881
882config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
883	def_bool y
884	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
885	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
886	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671
887	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300)
888	help
889	  Certain versions of clang and GCC do not support zicsr and zifencei via
890	  -march. This option causes an older ISA spec compatible with these older
891	  versions of clang and GCC to be passed to GAS, which has the same result
892	  as passing zicsr and zifencei to -march.
893
894config FPU
895	bool "FPU support"
896	default y
897	help
898	  Add support for floating point operations when an FPU is detected at
899	  boot. When this option is disabled, neither the kernel nor userspace
900	  may use the floating point unit.
901
902	  If you don't know what to do here, say Y.
903
904config IRQ_STACKS
905	bool "Independent irq & softirq stacks" if EXPERT
906	default y
907	select HAVE_IRQ_EXIT_ON_IRQ_STACK
908	select HAVE_SOFTIRQ_ON_OWN_STACK
909	help
910	  Add independent irq & softirq stacks for percpu to prevent kernel stack
911	  overflows. We may save some memory footprint by disabling IRQ_STACKS.
912
913config THREAD_SIZE_ORDER
914	int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT
915	range 0 4
916	default 1 if 32BIT
917	default 2
918	help
919	  Specify the Pages of thread stack size (from 4KB to 64KB), which also
920	  affects irq stack size, which is equal to thread stack size.
921
922config RISCV_MISALIGNED
923	bool
924	help
925	  Embed support for detecting and emulating misaligned
926	  scalar or vector loads and stores.
927
928config RISCV_SCALAR_MISALIGNED
929	bool
930	select RISCV_MISALIGNED
931	select SYSCTL_ARCH_UNALIGN_ALLOW
932	help
933	  Embed support for emulating misaligned loads and stores.
934
935config RISCV_VECTOR_MISALIGNED
936	bool
937	select RISCV_MISALIGNED
938	depends on RISCV_ISA_V
939	help
940	  Enable detecting support for vector misaligned loads and stores.
941
942choice
943	prompt "Unaligned Accesses Support"
944	default RISCV_PROBE_UNALIGNED_ACCESS
945	help
946	  This determines the level of support for unaligned accesses. This
947	  information is used by the kernel to perform optimizations. It is also
948	  exposed to user space via the hwprobe syscall. The hardware will be
949	  probed at boot by default.
950
951config RISCV_PROBE_UNALIGNED_ACCESS
952	bool "Probe for hardware unaligned access support"
953	select RISCV_SCALAR_MISALIGNED
954	help
955	  During boot, the kernel will run a series of tests to determine the
956	  speed of unaligned accesses. This probing will dynamically determine
957	  the speed of unaligned accesses on the underlying system. If unaligned
958	  memory accesses trap into the kernel as they are not supported by the
959	  system, the kernel will emulate the unaligned accesses to preserve the
960	  UABI.
961
962config RISCV_EMULATED_UNALIGNED_ACCESS
963	bool "Emulate unaligned access where system support is missing"
964	select RISCV_SCALAR_MISALIGNED
965	help
966	  If unaligned memory accesses trap into the kernel as they are not
967	  supported by the system, the kernel will emulate the unaligned
968	  accesses to preserve the UABI. When the underlying system does support
969	  unaligned accesses, the unaligned accesses are assumed to be slow.
970
971config RISCV_SLOW_UNALIGNED_ACCESS
972	bool "Assume the system supports slow unaligned memory accesses"
973	depends on NONPORTABLE
974	help
975	  Assume that the system supports slow unaligned memory accesses. The
976	  kernel and userspace programs may not be able to run at all on systems
977	  that do not support unaligned memory accesses.
978
979config RISCV_EFFICIENT_UNALIGNED_ACCESS
980	bool "Assume the system supports fast unaligned memory accesses"
981	depends on NONPORTABLE
982	select DCACHE_WORD_ACCESS if MMU
983	select HAVE_EFFICIENT_UNALIGNED_ACCESS
984	help
985	  Assume that the system supports fast unaligned memory accesses. When
986	  enabled, this option improves the performance of the kernel on such
987	  systems. However, the kernel and userspace programs will run much more
988	  slowly, or will not be able to run at all, on systems that do not
989	  support efficient unaligned memory accesses.
990
991endchoice
992
993choice
994	prompt "Vector unaligned Accesses Support"
995	depends on RISCV_ISA_V
996	default RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
997	help
998	  This determines the level of support for vector unaligned accesses. This
999	  information is used by the kernel to perform optimizations. It is also
1000	  exposed to user space via the hwprobe syscall. The hardware will be
1001	  probed at boot by default.
1002
1003config RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
1004	bool "Probe speed of vector unaligned accesses"
1005	select RISCV_VECTOR_MISALIGNED
1006	depends on RISCV_ISA_V
1007	help
1008	  During boot, the kernel will run a series of tests to determine the
1009	  speed of vector unaligned accesses if they are supported. This probing
1010	  will dynamically determine the speed of vector unaligned accesses on
1011	  the underlying system if they are supported.
1012
1013config RISCV_SLOW_VECTOR_UNALIGNED_ACCESS
1014	bool "Assume the system supports slow vector unaligned memory accesses"
1015	depends on NONPORTABLE
1016	help
1017	  Assume that the system supports slow vector unaligned memory accesses. The
1018	  kernel and userspace programs may not be able to run at all on systems
1019	  that do not support unaligned memory accesses.
1020
1021config RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS
1022	bool "Assume the system supports fast vector unaligned memory accesses"
1023	depends on NONPORTABLE
1024	help
1025	  Assume that the system supports fast vector unaligned memory accesses. When
1026	  enabled, this option improves the performance of the kernel on such
1027	  systems. However, the kernel and userspace programs will run much more
1028	  slowly, or will not be able to run at all, on systems that do not
1029	  support efficient unaligned memory accesses.
1030
1031endchoice
1032
1033source "arch/riscv/Kconfig.vendor"
1034
1035endmenu # "Platform type"
1036
1037menu "Kernel features"
1038
1039source "kernel/Kconfig.hz"
1040
1041config RISCV_SBI_V01
1042	bool "SBI v0.1 support"
1043	depends on RISCV_SBI
1044	help
1045	  This config allows kernel to use SBI v0.1 APIs. This will be
1046	  deprecated in future once legacy M-mode software are no longer in use.
1047
1048config RISCV_BOOT_SPINWAIT
1049	bool "Spinwait booting method"
1050	depends on SMP
1051	default y if RISCV_SBI_V01 || RISCV_M_MODE
1052	help
1053	  This enables support for booting Linux via spinwait method. In the
1054	  spinwait method, all cores randomly jump to Linux. One of the cores
1055	  gets chosen via lottery and all other keep spinning on a percpu
1056	  variable. This method cannot support CPU hotplug and sparse hartid
1057	  scheme. It should be only enabled for M-mode Linux or platforms relying
1058	  on older firmware without SBI HSM extension. All other platforms should
1059	  rely on ordered booting via SBI HSM extension which gets chosen
1060	  dynamically at runtime if the firmware supports it.
1061
1062	  Since spinwait is incompatible with sparse hart IDs, it requires
1063	  NR_CPUS be large enough to contain the physical hart ID of the first
1064	  hart to enter Linux.
1065
1066	  If unsure what to do here, say N.
1067
1068config ARCH_SUPPORTS_KEXEC
1069	def_bool y
1070
1071config ARCH_SELECTS_KEXEC
1072	def_bool y
1073	depends on KEXEC
1074	select HOTPLUG_CPU if SMP
1075
1076config ARCH_SUPPORTS_KEXEC_FILE
1077	def_bool 64BIT
1078
1079config ARCH_SELECTS_KEXEC_FILE
1080	def_bool y
1081	depends on KEXEC_FILE
1082	select HAVE_IMA_KEXEC if IMA
1083	select KEXEC_ELF
1084
1085config ARCH_SUPPORTS_KEXEC_PURGATORY
1086	def_bool ARCH_SUPPORTS_KEXEC_FILE
1087
1088config ARCH_SUPPORTS_CRASH_DUMP
1089	def_bool y
1090
1091config ARCH_DEFAULT_CRASH_DUMP
1092	def_bool y
1093
1094config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1095	def_bool CRASH_RESERVE
1096
1097config COMPAT
1098	bool "Kernel support for 32-bit U-mode"
1099	default 64BIT
1100	depends on 64BIT && MMU
1101	help
1102	  This option enables support for a 32-bit U-mode running under a 64-bit
1103	  kernel at S-mode. riscv32-specific components such as system calls,
1104	  the user helper functions (vdso), signal rt_frame functions and the
1105	  ptrace interface are handled appropriately by the kernel.
1106
1107	  If you want to execute 32-bit userspace applications, say Y.
1108
1109config PARAVIRT
1110	bool "Enable paravirtualization code"
1111	depends on RISCV_SBI
1112	help
1113	  This changes the kernel so it can modify itself when it is run
1114	  under a hypervisor, potentially improving performance significantly
1115	  over full virtualization.
1116
1117config PARAVIRT_TIME_ACCOUNTING
1118	bool "Paravirtual steal time accounting"
1119	depends on PARAVIRT
1120	help
1121	  Select this option to enable fine granularity task steal time
1122	  accounting. Time spent executing other tasks in parallel with
1123	  the current vCPU is discounted from the vCPU power. To account for
1124	  that, there can be a small performance impact.
1125
1126	  If in doubt, say N here.
1127
1128config RELOCATABLE
1129	bool "Build a relocatable kernel"
1130	depends on !XIP_KERNEL
1131	select MODULE_SECTIONS if MODULES
1132	select ARCH_VMLINUX_NEEDS_RELOCS
1133	help
1134          This builds a kernel as a Position Independent Executable (PIE),
1135          which retains all relocation metadata required to relocate the
1136          kernel binary at runtime to a different virtual address than the
1137          address it was linked at.
1138          Since RISCV uses the RELA relocation format, this requires a
1139          relocation pass at runtime even if the kernel is loaded at the
1140          same address it was linked at.
1141
1142          If unsure, say N.
1143
1144config RANDOMIZE_BASE
1145        bool "Randomize the address of the kernel image"
1146        select RELOCATABLE
1147        depends on MMU && 64BIT && !XIP_KERNEL
1148        help
1149          Randomizes the virtual address at which the kernel image is
1150          loaded, as a security feature that deters exploit attempts
1151          relying on knowledge of the location of kernel internals.
1152
1153          It is the bootloader's job to provide entropy, by passing a
1154          random u64 value in /chosen/kaslr-seed at kernel entry.
1155
1156          When booting via the UEFI stub, it will invoke the firmware's
1157          EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1158          to the kernel proper. In addition, it will randomise the physical
1159          location of the kernel Image as well.
1160
1161          If unsure, say N.
1162
1163endmenu # "Kernel features"
1164
1165menu "Boot options"
1166
1167config CMDLINE
1168	string "Built-in kernel command line"
1169	help
1170	  For most platforms, the arguments for the kernel's command line
1171	  are provided at run-time, during boot. However, there are cases
1172	  where either no arguments are being provided or the provided
1173	  arguments are insufficient or even invalid.
1174
1175	  When that occurs, it is possible to define a built-in command
1176	  line here and choose how the kernel should use it later on.
1177
1178choice
1179	prompt "Built-in command line usage"
1180	depends on CMDLINE != ""
1181	default CMDLINE_FALLBACK
1182	help
1183	  Choose how the kernel will handle the provided built-in command
1184	  line.
1185
1186config CMDLINE_FALLBACK
1187	bool "Use bootloader kernel arguments if available"
1188	help
1189	  Use the built-in command line as fallback in case we get nothing
1190	  during boot. This is the default behaviour.
1191
1192config CMDLINE_EXTEND
1193	bool "Extend bootloader kernel arguments"
1194	help
1195	  The built-in command line will be appended to the command-
1196	  line arguments provided during boot. This is useful in
1197	  cases where the provided arguments are insufficient and
1198	  you don't want to or cannot modify them.
1199
1200config CMDLINE_FORCE
1201	bool "Always use the default kernel command string"
1202	help
1203	  Always use the built-in command line, even if we get one during
1204	  boot. This is useful in case you need to override the provided
1205	  command line on systems where you don't have or want control
1206	  over it.
1207
1208endchoice
1209
1210config EFI_STUB
1211	bool
1212
1213config EFI
1214	bool "UEFI runtime support"
1215	depends on OF && !XIP_KERNEL
1216	depends on MMU
1217	default y
1218	select ARCH_SUPPORTS_ACPI if 64BIT
1219	select EFI_GENERIC_STUB
1220	select EFI_PARAMS_FROM_FDT
1221	select EFI_RUNTIME_WRAPPERS
1222	select EFI_STUB
1223	select LIBFDT
1224	select RISCV_ISA_C
1225	select UCS2_STRING
1226	help
1227	  This option provides support for runtime services provided
1228	  by UEFI firmware (such as non-volatile variables, realtime
1229	  clock, and platform reset). A UEFI stub is also provided to
1230	  allow the kernel to be booted as an EFI application. This
1231	  is only useful on systems that have UEFI firmware.
1232
1233config DMI
1234	bool "Enable support for SMBIOS (DMI) tables"
1235	depends on EFI
1236	default y
1237	help
1238	  This enables SMBIOS/DMI feature for systems.
1239
1240	  This option is only useful on systems that have UEFI firmware.
1241	  However, even with this option, the resultant kernel should
1242	  continue to boot on existing non-UEFI platforms.
1243
1244config CC_HAVE_STACKPROTECTOR_TLS
1245	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
1246
1247config STACKPROTECTOR_PER_TASK
1248	def_bool y
1249	depends on !RANDSTRUCT
1250	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
1251
1252config PHYS_RAM_BASE_FIXED
1253	bool "Explicitly specified physical RAM address"
1254	depends on NONPORTABLE
1255	default n
1256
1257config PHYS_RAM_BASE
1258	hex "Platform Physical RAM address"
1259	depends on PHYS_RAM_BASE_FIXED
1260	default "0x80000000"
1261	help
1262	  This is the physical address of RAM in the system. It has to be
1263	  explicitly specified to run early relocations of read-write data
1264	  from flash to RAM.
1265
1266config XIP_KERNEL
1267	bool "Kernel Execute-In-Place from ROM"
1268	depends on MMU && SPARSEMEM && NONPORTABLE
1269	# This prevents XIP from being enabled by all{yes,mod}config, which
1270	# fail to build since XIP doesn't support large kernels.
1271	depends on !COMPILE_TEST
1272	select PHYS_RAM_BASE_FIXED
1273	help
1274	  Execute-In-Place allows the kernel to run from non-volatile storage
1275	  directly addressable by the CPU, such as NOR flash. This saves RAM
1276	  space since the text section of the kernel is not loaded from flash
1277	  to RAM.  Read-write sections, such as the data section and stack,
1278	  are still copied to RAM.  The XIP kernel is not compressed since
1279	  it has to run directly from flash, so it will take more space to
1280	  store it.  The flash address used to link the kernel object files,
1281	  and for storing it, is configuration dependent. Therefore, if you
1282	  say Y here, you must know the proper physical address where to
1283	  store the kernel image depending on your own flash memory usage.
1284
1285	  Also note that the make target becomes "make xipImage" rather than
1286	  "make zImage" or "make Image".  The final kernel binary to put in
1287	  ROM memory will be arch/riscv/boot/xipImage.
1288
1289	  SPARSEMEM is required because the kernel text and rodata that are
1290	  flash resident are not backed by memmap, then any attempt to get
1291	  a struct page on those regions will trigger a fault.
1292
1293	  If unsure, say N.
1294
1295config XIP_PHYS_ADDR
1296	hex "XIP Kernel Physical Location"
1297	depends on XIP_KERNEL
1298	default "0x21000000"
1299	help
1300	  This is the physical address in your flash memory the kernel will
1301	  be linked for and stored to.  This address is dependent on your
1302	  own flash usage.
1303
1304config RISCV_ISA_FALLBACK
1305	bool "Permit falling back to parsing riscv,isa for extension support by default"
1306	default y
1307	help
1308	  Parsing the "riscv,isa" devicetree property has been deprecated and
1309	  replaced by a list of explicitly defined strings. For compatibility
1310	  with existing platforms, the kernel will fall back to parsing the
1311	  "riscv,isa" property if the replacements are not found.
1312
1313	  Selecting N here will result in a kernel that does not use the
1314	  fallback, unless the commandline "riscv_isa_fallback" parameter is
1315	  present.
1316
1317	  Please see the dt-binding, located at
1318	  Documentation/devicetree/bindings/riscv/extensions.yaml for details
1319	  on the replacement properties, "riscv,isa-base" and
1320	  "riscv,isa-extensions".
1321
1322config BUILTIN_DTB
1323	bool "Built-in device tree"
1324	depends on OF && NONPORTABLE
1325	select GENERIC_BUILTIN_DTB
1326	help
1327	  Build a device tree into the Linux image.
1328	  This option should be selected if no bootloader is being used.
1329	  If unsure, say N.
1330
1331
1332config BUILTIN_DTB_NAME
1333	string "Built-in device tree source"
1334	depends on BUILTIN_DTB
1335	help
1336	  DTS file path (without suffix, relative to arch/riscv/boot/dts)
1337	  for the DTS file that will be used to produce the DTB linked into the
1338	  kernel.
1339
1340endmenu # "Boot options"
1341
1342config PORTABLE
1343	bool
1344	default !NONPORTABLE
1345	select EFI
1346	select MMU
1347	select OF
1348
1349config ARCH_PROC_KCORE_TEXT
1350	def_bool y
1351
1352menu "Power management options"
1353
1354source "kernel/power/Kconfig"
1355
1356config ARCH_HIBERNATION_POSSIBLE
1357	def_bool y
1358
1359config ARCH_HIBERNATION_HEADER
1360	def_bool HIBERNATION
1361
1362config ARCH_SUSPEND_POSSIBLE
1363	def_bool y
1364
1365endmenu # "Power management options"
1366
1367menu "CPU Power Management"
1368
1369source "drivers/cpuidle/Kconfig"
1370
1371source "drivers/cpufreq/Kconfig"
1372
1373endmenu # "CPU Power Management"
1374
1375source "arch/riscv/kvm/Kconfig"
1376
1377source "drivers/acpi/Kconfig"
1378