xref: /linux/arch/riscv/Kconfig (revision 2eff01ee2881becc9daaa0d53477ec202136b1f4)
1# SPDX-License-Identifier: GPL-2.0-only
2#
3# For a description of the syntax of this configuration file,
4# see Documentation/kbuild/kconfig-language.rst.
5#
6
7config 64BIT
8	bool
9
10config 32BIT
11	bool
12
13config RISCV
14	def_bool y
15	select ACPI_GENERIC_GSI if ACPI
16	select ACPI_MCFG if (ACPI && PCI)
17	select ACPI_PPTT if ACPI
18	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
19	select ACPI_SPCR_TABLE if ACPI
20	select ARCH_DMA_DEFAULT_COHERENT
21	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
22	select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM_VMEMMAP
23	select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
24	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
25	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
26	select ARCH_HAS_BINFMT_FLAT
27	select ARCH_HAS_CURRENT_STACK_POINTER
28	select ARCH_HAS_DEBUG_VIRTUAL if MMU
29	select ARCH_HAS_DEBUG_VM_PGTABLE
30	select ARCH_HAS_DEBUG_WX
31	select ARCH_HAS_FAST_MULTIPLIER
32	select ARCH_HAS_FORTIFY_SOURCE
33	select ARCH_HAS_GCOV_PROFILE_ALL
34	select ARCH_HAS_GIGANTIC_PAGE
35	select ARCH_HAS_KCOV
36	select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU
37	select ARCH_HAS_MEMBARRIER_CALLBACKS
38	select ARCH_HAS_MEMBARRIER_SYNC_CORE
39	select ARCH_HAS_MMIOWB
40	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
41	select ARCH_HAS_PMEM_API
42	select ARCH_HAS_PREEMPT_LAZY
43	select ARCH_HAS_PREPARE_SYNC_CORE_CMD
44	select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU
45	select ARCH_HAS_PTE_SPECIAL
46	select ARCH_HAS_SET_DIRECT_MAP if MMU
47	select ARCH_HAS_SET_MEMORY if MMU
48	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
49	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
50	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
51	select ARCH_HAS_SYSCALL_WRAPPER
52	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
53	select ARCH_HAS_UBSAN
54	select ARCH_HAS_VDSO_TIME_DATA
55	select ARCH_KEEP_MEMBLOCK if ACPI
56	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE	if 64BIT && MMU
57	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
58	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
59	select ARCH_STACKWALK
60	select ARCH_SUPPORTS_ATOMIC_RMW
61	select ARCH_SUPPORTS_CFI_CLANG
62	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
63	select ARCH_SUPPORTS_HUGETLBFS if MMU
64	# LLD >= 14: https://github.com/llvm/llvm-project/issues/50505
65	select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000
66	select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000
67	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
68	select ARCH_SUPPORTS_PER_VMA_LOCK if MMU
69	select ARCH_SUPPORTS_RT
70	select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK
71	select ARCH_USE_CMPXCHG_LOCKREF if 64BIT
72	select ARCH_USE_MEMTEST
73	select ARCH_USE_QUEUED_RWLOCKS
74	select ARCH_USE_SYM_ANNOTATIONS
75	select ARCH_USES_CFI_TRAPS if CFI_CLANG
76	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
77	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
78	select ARCH_WANT_FRAME_POINTERS
79	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT
80	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
81	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
82	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
83	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
84	select ARCH_WANTS_NO_INSTR
85	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
86	select ARCH_WEAK_RELEASE_ACQUIRE if ARCH_USE_QUEUED_SPINLOCKS
87	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
88	select BUILDTIME_TABLE_SORT if MMU
89	select CLINT_TIMER if RISCV_M_MODE
90	select CLONE_BACKWARDS
91	select COMMON_CLK
92	select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND
93	select EDAC_SUPPORT
94	select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE)
95	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE
96	select GENERIC_ARCH_TOPOLOGY
97	select GENERIC_ATOMIC64 if !64BIT
98	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
99	select GENERIC_CPU_DEVICES
100	select GENERIC_CPU_VULNERABILITIES
101	select GENERIC_EARLY_IOREMAP
102	select GENERIC_ENTRY
103	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
104	select GENERIC_IDLE_POLL_SETUP
105	select GENERIC_IOREMAP if MMU
106	select GENERIC_IRQ_IPI if SMP
107	select GENERIC_IRQ_IPI_MUX if SMP
108	select GENERIC_IRQ_MULTI_HANDLER
109	select GENERIC_IRQ_SHOW
110	select GENERIC_IRQ_SHOW_LEVEL
111	select GENERIC_LIB_DEVMEM_IS_ALLOWED
112	select GENERIC_PCI_IOMAP
113	select GENERIC_PTDUMP if MMU
114	select GENERIC_SCHED_CLOCK
115	select GENERIC_SMP_IDLE_THREAD
116	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
117	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
118	select HARDIRQS_SW_RESEND
119	select HAS_IOPORT if MMU
120	select HAVE_ALIGNED_STRUCT_PAGE
121	select HAVE_ARCH_AUDITSYSCALL
122	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
123	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT
124	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
125	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
126	select HAVE_ARCH_KASAN if MMU && 64BIT
127	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
128	select HAVE_ARCH_KFENCE if MMU && 64BIT
129	select HAVE_ARCH_KGDB if !XIP_KERNEL
130	select HAVE_ARCH_KGDB_QXFER_PKT
131	select HAVE_ARCH_MMAP_RND_BITS if MMU
132	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
133	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
134	select HAVE_ARCH_SECCOMP_FILTER
135	select HAVE_ARCH_STACKLEAK
136	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
137	select HAVE_ARCH_TRACEHOOK
138	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
139	select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD
140	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
141	select HAVE_ASM_MODVERSIONS
142	select HAVE_CONTEXT_TRACKING_USER
143	select HAVE_DEBUG_KMEMLEAK
144	select HAVE_DMA_CONTIGUOUS if MMU
145	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE)
146	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
147	select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
148	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
149	select HAVE_FUNCTION_GRAPH_TRACER
150	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
151	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
152	select HAVE_EBPF_JIT if MMU
153	select HAVE_GUP_FAST if MMU
154	select HAVE_FUNCTION_ARG_ACCESS_API
155	select HAVE_FUNCTION_ERROR_INJECTION
156	select HAVE_GCC_PLUGINS
157	select HAVE_GENERIC_VDSO if MMU && 64BIT
158	select HAVE_IRQ_TIME_ACCOUNTING
159	select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT
160	select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT
161	select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT
162	select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT
163	select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT
164	select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT
165	select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT
166	select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT
167	select HAVE_KPROBES if !XIP_KERNEL
168	select HAVE_KRETPROBES if !XIP_KERNEL
169	# https://github.com/ClangBuiltLinux/linux/issues/1881
170	select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD
171	select HAVE_MOVE_PMD
172	select HAVE_MOVE_PUD
173	select HAVE_PAGE_SIZE_4KB
174	select HAVE_PCI
175	select HAVE_PERF_EVENTS
176	select HAVE_PERF_REGS
177	select HAVE_PERF_USER_STACK_DUMP
178	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
179	select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL
180	select HAVE_REGS_AND_STACK_ACCESS_API
181	select HAVE_RETHOOK if !XIP_KERNEL
182	select HAVE_RSEQ
183	select HAVE_RUST if RUSTC_SUPPORTS_RISCV && CC_IS_CLANG
184	select HAVE_SAMPLE_FTRACE_DIRECT
185	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
186	select HAVE_STACKPROTECTOR
187	select HAVE_SYSCALL_TRACEPOINTS
188	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
189	select IRQ_DOMAIN
190	select IRQ_FORCED_THREADING
191	select KASAN_VMALLOC if KASAN
192	select LOCK_MM_AND_FIND_VMA
193	select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU
194	select MODULES_USE_ELF_RELA if MODULES
195	select OF
196	select OF_EARLY_FLATTREE
197	select OF_IRQ
198	select PCI_DOMAINS_GENERIC if PCI
199	select PCI_ECAM if (ACPI && PCI)
200	select PCI_MSI if PCI
201	select RISCV_ALTERNATIVE if !XIP_KERNEL
202	select RISCV_APLIC
203	select RISCV_IMSIC
204	select RISCV_INTC
205	select RISCV_TIMER if RISCV_SBI
206	select SIFIVE_PLIC
207	select SPARSE_IRQ
208	select SYSCTL_EXCEPTION_TRACE
209	select THREAD_INFO_IN_TASK
210	select TRACE_IRQFLAGS_SUPPORT
211	select UACCESS_MEMCPY if !MMU
212	select USER_STACKTRACE_SUPPORT
213	select ZONE_DMA32 if 64BIT
214
215config RUSTC_SUPPORTS_RISCV
216	def_bool y
217	depends on 64BIT
218	# Shadow call stack requires rustc version 1.82+ due to use of the
219	# -Zsanitizer=shadow-call-stack flag.
220	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
221
222config CLANG_SUPPORTS_DYNAMIC_FTRACE
223	def_bool CC_IS_CLANG
224	# https://github.com/ClangBuiltLinux/linux/issues/1817
225	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
226
227config GCC_SUPPORTS_DYNAMIC_FTRACE
228	def_bool CC_IS_GCC
229	depends on $(cc-option,-fpatchable-function-entry=8)
230
231config HAVE_SHADOW_CALL_STACK
232	def_bool $(cc-option,-fsanitize=shadow-call-stack)
233	# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769
234	depends on $(ld-option,--no-relax-gp)
235
236config RISCV_USE_LINKER_RELAXATION
237	def_bool y
238	# https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985
239	depends on !LD_IS_LLD || LLD_VERSION >= 150000
240
241# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6
242config ARCH_HAS_BROKEN_DWARF5
243	def_bool y
244	depends on RISCV_USE_LINKER_RELAXATION
245	# https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a
246	depends on AS_IS_LLVM && AS_VERSION < 180000
247	# https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77
248	depends on LD_IS_LLD && LLD_VERSION < 180000
249
250config ARCH_MMAP_RND_BITS_MIN
251	default 18 if 64BIT
252	default 8
253
254config ARCH_MMAP_RND_COMPAT_BITS_MIN
255	default 8
256
257# max bits determined by the following formula:
258#  VA_BITS - PAGE_SHIFT - 3
259config ARCH_MMAP_RND_BITS_MAX
260	default 24 if 64BIT # SV39 based
261	default 17
262
263config ARCH_MMAP_RND_COMPAT_BITS_MAX
264	default 17
265
266# set if we run in machine mode, cleared if we run in supervisor mode
267config RISCV_M_MODE
268	bool "Build a kernel that runs in machine mode"
269	depends on !MMU
270	default y
271	help
272	  Select this option if you want to run the kernel in M-mode,
273	  without the assistance of any other firmware.
274
275# set if we are running in S-mode and can use SBI calls
276config RISCV_SBI
277	bool
278	depends on !RISCV_M_MODE
279	default y
280
281config MMU
282	bool "MMU-based Paged Memory Management Support"
283	default y
284	help
285	  Select if you want MMU-based virtualised addressing space
286	  support by paged memory management. If unsure, say 'Y'.
287
288config PAGE_OFFSET
289	hex
290	default 0x80000000 if !MMU && RISCV_M_MODE
291	default 0x80200000 if !MMU
292	default 0xc0000000 if 32BIT
293	default 0xff60000000000000 if 64BIT
294
295config KASAN_SHADOW_OFFSET
296	hex
297	depends on KASAN_GENERIC
298	default 0xdfffffff00000000 if 64BIT
299	default 0xffffffff if 32BIT
300
301config ARCH_FLATMEM_ENABLE
302	def_bool !NUMA
303
304config ARCH_SPARSEMEM_ENABLE
305	def_bool y
306	depends on MMU
307	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
308	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
309
310config ARCH_SELECT_MEMORY_MODEL
311	def_bool ARCH_SPARSEMEM_ENABLE
312
313config ARCH_SUPPORTS_UPROBES
314	def_bool y
315
316config STACKTRACE_SUPPORT
317	def_bool y
318
319config GENERIC_BUG
320	def_bool y
321	depends on BUG
322	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
323
324config GENERIC_BUG_RELATIVE_POINTERS
325	bool
326
327config GENERIC_CALIBRATE_DELAY
328	def_bool y
329
330config GENERIC_CSUM
331	def_bool y
332
333config GENERIC_HWEIGHT
334	def_bool y
335
336config FIX_EARLYCON_MEM
337	def_bool MMU
338
339config ILLEGAL_POINTER_VALUE
340	hex
341	default 0 if 32BIT
342	default 0xdead000000000000 if 64BIT
343
344config PGTABLE_LEVELS
345	int
346	default 5 if 64BIT
347	default 2
348
349config LOCKDEP_SUPPORT
350	def_bool y
351
352config RISCV_DMA_NONCOHERENT
353	bool
354	select ARCH_HAS_DMA_PREP_COHERENT
355	select ARCH_HAS_SETUP_DMA_OPS
356	select ARCH_HAS_SYNC_DMA_FOR_CPU
357	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
358	select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB
359
360config RISCV_NONSTANDARD_CACHE_OPS
361	bool
362	help
363	  This enables function pointer support for non-standard noncoherent
364	  systems to handle cache management.
365
366config AS_HAS_INSN
367	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
368
369config AS_HAS_OPTION_ARCH
370	# https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4
371	def_bool y
372	depends on $(as-instr, .option arch$(comma) +m)
373
374source "arch/riscv/Kconfig.socs"
375source "arch/riscv/Kconfig.errata"
376
377menu "Platform type"
378
379config NONPORTABLE
380	bool "Allow configurations that result in non-portable kernels"
381	help
382	  RISC-V kernel binaries are compatible between all known systems
383	  whenever possible, but there are some use cases that can only be
384	  satisfied by configurations that result in kernel binaries that are
385	  not portable between systems.
386
387	  Selecting N does not guarantee kernels will be portable to all known
388	  systems.  Selecting any of the options guarded by NONPORTABLE will
389	  result in kernel binaries that are unlikely to be portable between
390	  systems.
391
392	  If unsure, say N.
393
394choice
395	prompt "Base ISA"
396	default ARCH_RV64I
397	help
398	  This selects the base ISA that this kernel will target and must match
399	  the target platform.
400
401config ARCH_RV32I
402	bool "RV32I"
403	depends on NONPORTABLE
404	select 32BIT
405	select GENERIC_LIB_ASHLDI3
406	select GENERIC_LIB_ASHRDI3
407	select GENERIC_LIB_LSHRDI3
408	select GENERIC_LIB_UCMPDI2
409
410config ARCH_RV64I
411	bool "RV64I"
412	select 64BIT
413	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
414	select SWIOTLB if MMU
415
416endchoice
417
418# We must be able to map all physical memory into the kernel, but the compiler
419# is still a bit more efficient when generating code if it's setup in a manner
420# such that it can only map 2GiB of memory.
421choice
422	prompt "Kernel Code Model"
423	default CMODEL_MEDLOW if 32BIT
424	default CMODEL_MEDANY if 64BIT
425
426	config CMODEL_MEDLOW
427		bool "medium low code model"
428	config CMODEL_MEDANY
429		bool "medium any code model"
430endchoice
431
432config MODULE_SECTIONS
433	bool
434	select HAVE_MOD_ARCH_SPECIFIC
435
436config SMP
437	bool "Symmetric Multi-Processing"
438	help
439	  This enables support for systems with more than one CPU.  If
440	  you say N here, the kernel will run on single and
441	  multiprocessor machines, but will use only one CPU of a
442	  multiprocessor machine. If you say Y here, the kernel will run
443	  on many, but not all, single processor machines. On a single
444	  processor machine, the kernel will run faster if you say N
445	  here.
446
447	  If you don't know what to do here, say N.
448
449config SCHED_MC
450	bool "Multi-core scheduler support"
451	depends on SMP
452	help
453	  Multi-core scheduler support improves the CPU scheduler's decision
454	  making when dealing with multi-core CPU chips at a cost of slightly
455	  increased overhead in some places. If unsure say N here.
456
457config NR_CPUS
458	int "Maximum number of CPUs (2-512)"
459	depends on SMP
460	range 2 512 if !RISCV_SBI_V01
461	range 2 32 if RISCV_SBI_V01 && 32BIT
462	range 2 64 if RISCV_SBI_V01 && 64BIT
463	default "32" if 32BIT
464	default "64" if 64BIT
465
466config HOTPLUG_CPU
467	bool "Support for hot-pluggable CPUs"
468	depends on SMP
469	select GENERIC_IRQ_MIGRATION
470	help
471
472	  Say Y here to experiment with turning CPUs off and on.  CPUs
473	  can be controlled through /sys/devices/system/cpu.
474
475	  Say N if you want to disable CPU hotplug.
476
477choice
478	prompt "CPU Tuning"
479	default TUNE_GENERIC
480
481config TUNE_GENERIC
482	bool "generic"
483
484endchoice
485
486# Common NUMA Features
487config NUMA
488	bool "NUMA Memory Allocation and Scheduler Support"
489	depends on SMP && MMU
490	select ARCH_SUPPORTS_NUMA_BALANCING
491	select GENERIC_ARCH_NUMA
492	select HAVE_SETUP_PER_CPU_AREA
493	select NEED_PER_CPU_EMBED_FIRST_CHUNK
494	select NEED_PER_CPU_PAGE_FIRST_CHUNK
495	select OF_NUMA
496	select USE_PERCPU_NUMA_NODE_ID
497	help
498	  Enable NUMA (Non-Uniform Memory Access) support.
499
500	  The kernel will try to allocate memory used by a CPU on the
501	  local memory of the CPU and add some more NUMA awareness to the kernel.
502
503config NODES_SHIFT
504	int "Maximum NUMA Nodes (as a power of 2)"
505	range 1 10
506	default "2"
507	depends on NUMA
508	help
509	  Specify the maximum number of NUMA Nodes available on the target
510	  system.  Increases memory reserved to accommodate various tables.
511
512choice
513	prompt "RISC-V spinlock type"
514	default RISCV_COMBO_SPINLOCKS
515
516config RISCV_TICKET_SPINLOCKS
517	bool "Using ticket spinlock"
518
519config RISCV_QUEUED_SPINLOCKS
520	bool "Using queued spinlock"
521	depends on SMP && MMU && NONPORTABLE
522	select ARCH_USE_QUEUED_SPINLOCKS
523	help
524	  The queued spinlock implementation requires the forward progress
525	  guarantee of cmpxchg()/xchg() atomic operations: CAS with Zabha or
526	  LR/SC with Ziccrse provide such guarantee.
527
528	  Select this if and only if Zabha or Ziccrse is available on your
529	  platform, RISCV_QUEUED_SPINLOCKS must not be selected for platforms
530	  without one of those extensions.
531
532	  If unsure, select RISCV_COMBO_SPINLOCKS, which will use qspinlocks
533	  when supported and otherwise ticket spinlocks.
534
535config RISCV_COMBO_SPINLOCKS
536	bool "Using combo spinlock"
537	depends on SMP && MMU
538	select ARCH_USE_QUEUED_SPINLOCKS
539	help
540	  Embed both queued spinlock and ticket lock so that the spinlock
541	  implementation can be chosen at runtime.
542
543endchoice
544
545config RISCV_ALTERNATIVE
546	bool
547	depends on !XIP_KERNEL
548	help
549	  This Kconfig allows the kernel to automatically patch the
550	  erratum or cpufeature required by the execution platform at run
551	  time. The code patching overhead is minimal, as it's only done
552	  once at boot and once on each module load.
553
554config RISCV_ALTERNATIVE_EARLY
555	bool
556	depends on RISCV_ALTERNATIVE
557	help
558	  Allows early patching of the kernel for special errata
559
560config RISCV_ISA_C
561	bool "Emit compressed instructions when building Linux"
562	default y
563	help
564	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
565	  when building Linux, which results in compressed instructions in the
566	  Linux binary.
567
568	  If you don't know what to do here, say Y.
569
570config RISCV_ISA_SUPM
571	bool "Supm extension for userspace pointer masking"
572	depends on 64BIT
573	default y
574	help
575	  Add support for pointer masking in userspace (Supm) when the
576	  underlying hardware extension (Smnpm or Ssnpm) is detected at boot.
577
578	  If this option is disabled, userspace will be unable to use
579	  the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API.
580
581config RISCV_ISA_SVNAPOT
582	bool "Svnapot extension support for supervisor mode NAPOT pages"
583	depends on 64BIT && MMU
584	depends on RISCV_ALTERNATIVE
585	default y
586	help
587	  Allow kernel to detect the Svnapot ISA-extension dynamically at boot
588	  time and enable its usage.
589
590	  The Svnapot extension is used to mark contiguous PTEs as a range
591	  of contiguous virtual-to-physical translations for a naturally
592	  aligned power-of-2 (NAPOT) granularity larger than the base 4KB page
593	  size. When HUGETLBFS is also selected this option unconditionally
594	  allocates some memory for each NAPOT page size supported by the kernel.
595	  When optimizing for low memory consumption and for platforms without
596	  the Svnapot extension, it may be better to say N here.
597
598	  If you don't know what to do here, say Y.
599
600config RISCV_ISA_SVPBMT
601	bool "Svpbmt extension support for supervisor mode page-based memory types"
602	depends on 64BIT && MMU
603	depends on RISCV_ALTERNATIVE
604	default y
605	help
606	   Adds support to dynamically detect the presence of the Svpbmt
607	   ISA-extension (Supervisor-mode: page-based memory types) and
608	   enable its usage.
609
610	   The memory type for a page contains a combination of attributes
611	   that indicate the cacheability, idempotency, and ordering
612	   properties for access to that page.
613
614	   The Svpbmt extension is only available on 64-bit cpus.
615
616	   If you don't know what to do here, say Y.
617
618config TOOLCHAIN_HAS_V
619	bool
620	default y
621	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv)
622	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv)
623	depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800
624	depends on AS_HAS_OPTION_ARCH
625
626config RISCV_ISA_V
627	bool "VECTOR extension support"
628	depends on TOOLCHAIN_HAS_V
629	depends on FPU
630	select DYNAMIC_SIGFRAME
631	default y
632	help
633	  Say N here if you want to disable all vector related procedure
634	  in the kernel.
635
636	  If you don't know what to do here, say Y.
637
638config RISCV_ISA_V_DEFAULT_ENABLE
639	bool "Enable userspace Vector by default"
640	depends on RISCV_ISA_V
641	default y
642	help
643	  Say Y here if you want to enable Vector in userspace by default.
644	  Otherwise, userspace has to make explicit prctl() call to enable
645	  Vector, or enable it via the sysctl interface.
646
647	  If you don't know what to do here, say Y.
648
649config RISCV_ISA_V_UCOPY_THRESHOLD
650	int "Threshold size for vectorized user copies"
651	depends on RISCV_ISA_V
652	default 768
653	help
654	  Prefer using vectorized copy_to_user()/copy_from_user() when the
655	  workload size exceeds this value.
656
657config RISCV_ISA_V_PREEMPTIVE
658	bool "Run kernel-mode Vector with kernel preemption"
659	depends on PREEMPTION
660	depends on RISCV_ISA_V
661	default y
662	help
663	  Usually, in-kernel SIMD routines are run with preemption disabled.
664	  Functions which envoke long running SIMD thus must yield core's
665	  vector unit to prevent blocking other tasks for too long.
666
667	  This config allows kernel to run SIMD without explicitly disable
668	  preemption. Enabling this config will result in higher memory
669	  consumption due to the allocation of per-task's kernel Vector context.
670
671config RISCV_ISA_ZAWRS
672	bool "Zawrs extension support for more efficient busy waiting"
673	depends on RISCV_ALTERNATIVE
674	default y
675	help
676	  The Zawrs extension defines instructions to be used in polling loops
677	  which allow a hart to enter a low-power state or to trap to the
678	  hypervisor while waiting on a store to a memory location. Enable the
679	  use of these instructions in the kernel when the Zawrs extension is
680	  detected at boot.
681
682config TOOLCHAIN_HAS_ZABHA
683	bool
684	default y
685	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zabha)
686	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zabha)
687	depends on AS_HAS_OPTION_ARCH
688
689config RISCV_ISA_ZABHA
690	bool "Zabha extension support for atomic byte/halfword operations"
691	depends on TOOLCHAIN_HAS_ZABHA
692	depends on RISCV_ALTERNATIVE
693	default y
694	help
695	  Enable the use of the Zabha ISA-extension to implement kernel
696	  byte/halfword atomic memory operations when it is detected at boot.
697
698	  If you don't know what to do here, say Y.
699
700config TOOLCHAIN_HAS_ZACAS
701	bool
702	default y
703	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas)
704	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas)
705	depends on AS_HAS_OPTION_ARCH
706
707config RISCV_ISA_ZACAS
708	bool "Zacas extension support for atomic CAS"
709	depends on TOOLCHAIN_HAS_ZACAS
710	depends on RISCV_ALTERNATIVE
711	default y
712	help
713	  Enable the use of the Zacas ISA-extension to implement kernel atomic
714	  cmpxchg operations when it is detected at boot.
715
716	  If you don't know what to do here, say Y.
717
718config TOOLCHAIN_HAS_ZBB
719	bool
720	default y
721	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
722	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
723	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
724	depends on AS_HAS_OPTION_ARCH
725
726# This symbol indicates that the toolchain supports all v1.0 vector crypto
727# extensions, including Zvk*, Zvbb, and Zvbc.  LLVM added all of these at once.
728# binutils added all except Zvkb, then added Zvkb.  So we just check for Zvkb.
729config TOOLCHAIN_HAS_VECTOR_CRYPTO
730	def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb)
731	depends on AS_HAS_OPTION_ARCH
732
733config RISCV_ISA_ZBA
734	bool "Zba extension support for bit manipulation instructions"
735	default y
736	help
737	   Add support for enabling optimisations in the kernel when the Zba
738	   extension is detected at boot.
739
740	   The Zba extension provides instructions to accelerate the generation
741	   of addresses that index into arrays of basic data types.
742
743	   If you don't know what to do here, say Y.
744
745config RISCV_ISA_ZBB
746	bool "Zbb extension support for bit manipulation instructions"
747	depends on TOOLCHAIN_HAS_ZBB
748	depends on RISCV_ALTERNATIVE
749	default y
750	help
751	   Adds support to dynamically detect the presence of the ZBB
752	   extension (basic bit manipulation) and enable its usage.
753
754	   The Zbb extension provides instructions to accelerate a number
755	   of bit-specific operations (count bit population, sign extending,
756	   bitrotation, etc).
757
758	   If you don't know what to do here, say Y.
759
760config TOOLCHAIN_HAS_ZBC
761	bool
762	default y
763	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc)
764	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc)
765	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
766	depends on AS_HAS_OPTION_ARCH
767
768config RISCV_ISA_ZBC
769	bool "Zbc extension support for carry-less multiplication instructions"
770	depends on TOOLCHAIN_HAS_ZBC
771	depends on MMU
772	depends on RISCV_ALTERNATIVE
773	default y
774	help
775	   Adds support to dynamically detect the presence of the Zbc
776	   extension (carry-less multiplication) and enable its usage.
777
778	   The Zbc extension could accelerate CRC (cyclic redundancy check)
779	   calculations.
780
781	   If you don't know what to do here, say Y.
782
783config RISCV_ISA_ZICBOM
784	bool "Zicbom extension support for non-coherent DMA operation"
785	depends on MMU
786	depends on RISCV_ALTERNATIVE
787	default y
788	select RISCV_DMA_NONCOHERENT
789	select DMA_DIRECT_REMAP
790	help
791	   Adds support to dynamically detect the presence of the ZICBOM
792	   extension (Cache Block Management Operations) and enable its
793	   usage.
794
795	   The Zicbom extension can be used to handle for example
796	   non-coherent DMA support on devices that need it.
797
798	   If you don't know what to do here, say Y.
799
800config RISCV_ISA_ZICBOZ
801	bool "Zicboz extension support for faster zeroing of memory"
802	depends on RISCV_ALTERNATIVE
803	default y
804	help
805	   Enable the use of the Zicboz extension (cbo.zero instruction)
806	   when available.
807
808	   The Zicboz extension is used for faster zeroing of memory.
809
810	   If you don't know what to do here, say Y.
811
812config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
813	def_bool y
814	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
815	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd
816	depends on AS_IS_GNU && AS_VERSION >= 23600
817	help
818	  Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer
819	  20191213 version, which moves some instructions from the I extension to
820	  the Zicsr and Zifencei extensions. This requires explicitly specifying
821	  Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr
822	  and Zifencei are supported in binutils from version 2.36 onwards.
823	  To make life easier, and avoid forcing toolchains that default to a
824	  newer ISA spec to version 2.2, relax the check to binutils >= 2.36.
825	  For clang < 17 or GCC < 11.3.0, for which this is not possible or need
826	  special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC.
827
828config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
829	def_bool y
830	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
831	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
832	# https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671
833	depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300)
834	help
835	  Certain versions of clang and GCC do not support zicsr and zifencei via
836	  -march. This option causes an older ISA spec compatible with these older
837	  versions of clang and GCC to be passed to GAS, which has the same result
838	  as passing zicsr and zifencei to -march.
839
840config FPU
841	bool "FPU support"
842	default y
843	help
844	  Say N here if you want to disable all floating-point related procedure
845	  in the kernel.
846
847	  If you don't know what to do here, say Y.
848
849config IRQ_STACKS
850	bool "Independent irq & softirq stacks" if EXPERT
851	default y
852	select HAVE_IRQ_EXIT_ON_IRQ_STACK
853	select HAVE_SOFTIRQ_ON_OWN_STACK
854	help
855	  Add independent irq & softirq stacks for percpu to prevent kernel stack
856	  overflows. We may save some memory footprint by disabling IRQ_STACKS.
857
858config THREAD_SIZE_ORDER
859	int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT
860	range 0 4
861	default 1 if 32BIT
862	default 2
863	help
864	  Specify the Pages of thread stack size (from 4KB to 64KB), which also
865	  affects irq stack size, which is equal to thread stack size.
866
867config RISCV_MISALIGNED
868	bool
869	help
870	  Embed support for detecting and emulating misaligned
871	  scalar or vector loads and stores.
872
873config RISCV_SCALAR_MISALIGNED
874	bool
875	select RISCV_MISALIGNED
876	select SYSCTL_ARCH_UNALIGN_ALLOW
877	help
878	  Embed support for emulating misaligned loads and stores.
879
880config RISCV_VECTOR_MISALIGNED
881	bool
882	select RISCV_MISALIGNED
883	depends on RISCV_ISA_V
884	help
885	  Enable detecting support for vector misaligned loads and stores.
886
887choice
888	prompt "Unaligned Accesses Support"
889	default RISCV_PROBE_UNALIGNED_ACCESS
890	help
891	  This determines the level of support for unaligned accesses. This
892	  information is used by the kernel to perform optimizations. It is also
893	  exposed to user space via the hwprobe syscall. The hardware will be
894	  probed at boot by default.
895
896config RISCV_PROBE_UNALIGNED_ACCESS
897	bool "Probe for hardware unaligned access support"
898	select RISCV_SCALAR_MISALIGNED
899	help
900	  During boot, the kernel will run a series of tests to determine the
901	  speed of unaligned accesses. This probing will dynamically determine
902	  the speed of unaligned accesses on the underlying system. If unaligned
903	  memory accesses trap into the kernel as they are not supported by the
904	  system, the kernel will emulate the unaligned accesses to preserve the
905	  UABI.
906
907config RISCV_EMULATED_UNALIGNED_ACCESS
908	bool "Emulate unaligned access where system support is missing"
909	select RISCV_SCALAR_MISALIGNED
910	help
911	  If unaligned memory accesses trap into the kernel as they are not
912	  supported by the system, the kernel will emulate the unaligned
913	  accesses to preserve the UABI. When the underlying system does support
914	  unaligned accesses, the unaligned accesses are assumed to be slow.
915
916config RISCV_SLOW_UNALIGNED_ACCESS
917	bool "Assume the system supports slow unaligned memory accesses"
918	depends on NONPORTABLE
919	help
920	  Assume that the system supports slow unaligned memory accesses. The
921	  kernel and userspace programs may not be able to run at all on systems
922	  that do not support unaligned memory accesses.
923
924config RISCV_EFFICIENT_UNALIGNED_ACCESS
925	bool "Assume the system supports fast unaligned memory accesses"
926	depends on NONPORTABLE
927	select DCACHE_WORD_ACCESS if MMU
928	select HAVE_EFFICIENT_UNALIGNED_ACCESS
929	help
930	  Assume that the system supports fast unaligned memory accesses. When
931	  enabled, this option improves the performance of the kernel on such
932	  systems. However, the kernel and userspace programs will run much more
933	  slowly, or will not be able to run at all, on systems that do not
934	  support efficient unaligned memory accesses.
935
936endchoice
937
938choice
939	prompt "Vector unaligned Accesses Support"
940	depends on RISCV_ISA_V
941	default RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
942	help
943	  This determines the level of support for vector unaligned accesses. This
944	  information is used by the kernel to perform optimizations. It is also
945	  exposed to user space via the hwprobe syscall. The hardware will be
946	  probed at boot by default.
947
948config RISCV_PROBE_VECTOR_UNALIGNED_ACCESS
949	bool "Probe speed of vector unaligned accesses"
950	select RISCV_VECTOR_MISALIGNED
951	depends on RISCV_ISA_V
952	help
953	  During boot, the kernel will run a series of tests to determine the
954	  speed of vector unaligned accesses if they are supported. This probing
955	  will dynamically determine the speed of vector unaligned accesses on
956	  the underlying system if they are supported.
957
958config RISCV_SLOW_VECTOR_UNALIGNED_ACCESS
959	bool "Assume the system supports slow vector unaligned memory accesses"
960	depends on NONPORTABLE
961	help
962	  Assume that the system supports slow vector unaligned memory accesses. The
963	  kernel and userspace programs may not be able to run at all on systems
964	  that do not support unaligned memory accesses.
965
966config RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS
967	bool "Assume the system supports fast vector unaligned memory accesses"
968	depends on NONPORTABLE
969	help
970	  Assume that the system supports fast vector unaligned memory accesses. When
971	  enabled, this option improves the performance of the kernel on such
972	  systems. However, the kernel and userspace programs will run much more
973	  slowly, or will not be able to run at all, on systems that do not
974	  support efficient unaligned memory accesses.
975
976endchoice
977
978source "arch/riscv/Kconfig.vendor"
979
980endmenu # "Platform type"
981
982menu "Kernel features"
983
984source "kernel/Kconfig.hz"
985
986config RISCV_SBI_V01
987	bool "SBI v0.1 support"
988	depends on RISCV_SBI
989	help
990	  This config allows kernel to use SBI v0.1 APIs. This will be
991	  deprecated in future once legacy M-mode software are no longer in use.
992
993config RISCV_BOOT_SPINWAIT
994	bool "Spinwait booting method"
995	depends on SMP
996	default y if RISCV_SBI_V01 || RISCV_M_MODE
997	help
998	  This enables support for booting Linux via spinwait method. In the
999	  spinwait method, all cores randomly jump to Linux. One of the cores
1000	  gets chosen via lottery and all other keep spinning on a percpu
1001	  variable. This method cannot support CPU hotplug and sparse hartid
1002	  scheme. It should be only enabled for M-mode Linux or platforms relying
1003	  on older firmware without SBI HSM extension. All other platforms should
1004	  rely on ordered booting via SBI HSM extension which gets chosen
1005	  dynamically at runtime if the firmware supports it.
1006
1007	  Since spinwait is incompatible with sparse hart IDs, it requires
1008	  NR_CPUS be large enough to contain the physical hart ID of the first
1009	  hart to enter Linux.
1010
1011	  If unsure what to do here, say N.
1012
1013config ARCH_SUPPORTS_KEXEC
1014	def_bool y
1015
1016config ARCH_SELECTS_KEXEC
1017	def_bool y
1018	depends on KEXEC
1019	select HOTPLUG_CPU if SMP
1020
1021config ARCH_SUPPORTS_KEXEC_FILE
1022	def_bool 64BIT
1023
1024config ARCH_SELECTS_KEXEC_FILE
1025	def_bool y
1026	depends on KEXEC_FILE
1027	select HAVE_IMA_KEXEC if IMA
1028	select KEXEC_ELF
1029
1030config ARCH_SUPPORTS_KEXEC_PURGATORY
1031	def_bool ARCH_SUPPORTS_KEXEC_FILE
1032
1033config ARCH_SUPPORTS_CRASH_DUMP
1034	def_bool y
1035
1036config ARCH_DEFAULT_CRASH_DUMP
1037	def_bool y
1038
1039config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1040	def_bool CRASH_RESERVE
1041
1042config COMPAT
1043	bool "Kernel support for 32-bit U-mode"
1044	default 64BIT
1045	depends on 64BIT && MMU
1046	help
1047	  This option enables support for a 32-bit U-mode running under a 64-bit
1048	  kernel at S-mode. riscv32-specific components such as system calls,
1049	  the user helper functions (vdso), signal rt_frame functions and the
1050	  ptrace interface are handled appropriately by the kernel.
1051
1052	  If you want to execute 32-bit userspace applications, say Y.
1053
1054config PARAVIRT
1055	bool "Enable paravirtualization code"
1056	depends on RISCV_SBI
1057	help
1058	  This changes the kernel so it can modify itself when it is run
1059	  under a hypervisor, potentially improving performance significantly
1060	  over full virtualization.
1061
1062config PARAVIRT_TIME_ACCOUNTING
1063	bool "Paravirtual steal time accounting"
1064	depends on PARAVIRT
1065	help
1066	  Select this option to enable fine granularity task steal time
1067	  accounting. Time spent executing other tasks in parallel with
1068	  the current vCPU is discounted from the vCPU power. To account for
1069	  that, there can be a small performance impact.
1070
1071	  If in doubt, say N here.
1072
1073config RELOCATABLE
1074	bool "Build a relocatable kernel"
1075	depends on MMU && 64BIT && !XIP_KERNEL
1076	select MODULE_SECTIONS if MODULES
1077	help
1078          This builds a kernel as a Position Independent Executable (PIE),
1079          which retains all relocation metadata required to relocate the
1080          kernel binary at runtime to a different virtual address than the
1081          address it was linked at.
1082          Since RISCV uses the RELA relocation format, this requires a
1083          relocation pass at runtime even if the kernel is loaded at the
1084          same address it was linked at.
1085
1086          If unsure, say N.
1087
1088config RANDOMIZE_BASE
1089        bool "Randomize the address of the kernel image"
1090        select RELOCATABLE
1091        depends on MMU && 64BIT && !XIP_KERNEL
1092        help
1093          Randomizes the virtual address at which the kernel image is
1094          loaded, as a security feature that deters exploit attempts
1095          relying on knowledge of the location of kernel internals.
1096
1097          It is the bootloader's job to provide entropy, by passing a
1098          random u64 value in /chosen/kaslr-seed at kernel entry.
1099
1100          When booting via the UEFI stub, it will invoke the firmware's
1101          EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1102          to the kernel proper. In addition, it will randomise the physical
1103          location of the kernel Image as well.
1104
1105          If unsure, say N.
1106
1107endmenu # "Kernel features"
1108
1109menu "Boot options"
1110
1111config CMDLINE
1112	string "Built-in kernel command line"
1113	help
1114	  For most platforms, the arguments for the kernel's command line
1115	  are provided at run-time, during boot. However, there are cases
1116	  where either no arguments are being provided or the provided
1117	  arguments are insufficient or even invalid.
1118
1119	  When that occurs, it is possible to define a built-in command
1120	  line here and choose how the kernel should use it later on.
1121
1122choice
1123	prompt "Built-in command line usage"
1124	depends on CMDLINE != ""
1125	default CMDLINE_FALLBACK
1126	help
1127	  Choose how the kernel will handle the provided built-in command
1128	  line.
1129
1130config CMDLINE_FALLBACK
1131	bool "Use bootloader kernel arguments if available"
1132	help
1133	  Use the built-in command line as fallback in case we get nothing
1134	  during boot. This is the default behaviour.
1135
1136config CMDLINE_EXTEND
1137	bool "Extend bootloader kernel arguments"
1138	help
1139	  The command-line arguments provided during boot will be
1140	  appended to the built-in command line. This is useful in
1141	  cases where the provided arguments are insufficient and
1142	  you don't want to or cannot modify them.
1143
1144config CMDLINE_FORCE
1145	bool "Always use the default kernel command string"
1146	help
1147	  Always use the built-in command line, even if we get one during
1148	  boot. This is useful in case you need to override the provided
1149	  command line on systems where you don't have or want control
1150	  over it.
1151
1152endchoice
1153
1154config EFI_STUB
1155	bool
1156
1157config EFI
1158	bool "UEFI runtime support"
1159	depends on OF && !XIP_KERNEL
1160	depends on MMU
1161	default y
1162	select ARCH_SUPPORTS_ACPI if 64BIT
1163	select EFI_GENERIC_STUB
1164	select EFI_PARAMS_FROM_FDT
1165	select EFI_RUNTIME_WRAPPERS
1166	select EFI_STUB
1167	select LIBFDT
1168	select RISCV_ISA_C
1169	select UCS2_STRING
1170	help
1171	  This option provides support for runtime services provided
1172	  by UEFI firmware (such as non-volatile variables, realtime
1173	  clock, and platform reset). A UEFI stub is also provided to
1174	  allow the kernel to be booted as an EFI application. This
1175	  is only useful on systems that have UEFI firmware.
1176
1177config DMI
1178	bool "Enable support for SMBIOS (DMI) tables"
1179	depends on EFI
1180	default y
1181	help
1182	  This enables SMBIOS/DMI feature for systems.
1183
1184	  This option is only useful on systems that have UEFI firmware.
1185	  However, even with this option, the resultant kernel should
1186	  continue to boot on existing non-UEFI platforms.
1187
1188config CC_HAVE_STACKPROTECTOR_TLS
1189	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
1190
1191config STACKPROTECTOR_PER_TASK
1192	def_bool y
1193	depends on !RANDSTRUCT
1194	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
1195
1196config PHYS_RAM_BASE_FIXED
1197	bool "Explicitly specified physical RAM address"
1198	depends on NONPORTABLE
1199	default n
1200
1201config PHYS_RAM_BASE
1202	hex "Platform Physical RAM address"
1203	depends on PHYS_RAM_BASE_FIXED
1204	default "0x80000000"
1205	help
1206	  This is the physical address of RAM in the system. It has to be
1207	  explicitly specified to run early relocations of read-write data
1208	  from flash to RAM.
1209
1210config XIP_KERNEL
1211	bool "Kernel Execute-In-Place from ROM"
1212	depends on MMU && SPARSEMEM && NONPORTABLE
1213	# This prevents XIP from being enabled by all{yes,mod}config, which
1214	# fail to build since XIP doesn't support large kernels.
1215	depends on !COMPILE_TEST
1216	select PHYS_RAM_BASE_FIXED
1217	help
1218	  Execute-In-Place allows the kernel to run from non-volatile storage
1219	  directly addressable by the CPU, such as NOR flash. This saves RAM
1220	  space since the text section of the kernel is not loaded from flash
1221	  to RAM.  Read-write sections, such as the data section and stack,
1222	  are still copied to RAM.  The XIP kernel is not compressed since
1223	  it has to run directly from flash, so it will take more space to
1224	  store it.  The flash address used to link the kernel object files,
1225	  and for storing it, is configuration dependent. Therefore, if you
1226	  say Y here, you must know the proper physical address where to
1227	  store the kernel image depending on your own flash memory usage.
1228
1229	  Also note that the make target becomes "make xipImage" rather than
1230	  "make zImage" or "make Image".  The final kernel binary to put in
1231	  ROM memory will be arch/riscv/boot/xipImage.
1232
1233	  SPARSEMEM is required because the kernel text and rodata that are
1234	  flash resident are not backed by memmap, then any attempt to get
1235	  a struct page on those regions will trigger a fault.
1236
1237	  If unsure, say N.
1238
1239config XIP_PHYS_ADDR
1240	hex "XIP Kernel Physical Location"
1241	depends on XIP_KERNEL
1242	default "0x21000000"
1243	help
1244	  This is the physical address in your flash memory the kernel will
1245	  be linked for and stored to.  This address is dependent on your
1246	  own flash usage.
1247
1248config RISCV_ISA_FALLBACK
1249	bool "Permit falling back to parsing riscv,isa for extension support by default"
1250	default y
1251	help
1252	  Parsing the "riscv,isa" devicetree property has been deprecated and
1253	  replaced by a list of explicitly defined strings. For compatibility
1254	  with existing platforms, the kernel will fall back to parsing the
1255	  "riscv,isa" property if the replacements are not found.
1256
1257	  Selecting N here will result in a kernel that does not use the
1258	  fallback, unless the commandline "riscv_isa_fallback" parameter is
1259	  present.
1260
1261	  Please see the dt-binding, located at
1262	  Documentation/devicetree/bindings/riscv/extensions.yaml for details
1263	  on the replacement properties, "riscv,isa-base" and
1264	  "riscv,isa-extensions".
1265
1266config BUILTIN_DTB
1267	bool "Built-in device tree"
1268	depends on OF && NONPORTABLE
1269	help
1270	  Build a device tree into the Linux image.
1271	  This option should be selected if no bootloader is being used.
1272	  If unsure, say N.
1273
1274
1275config BUILTIN_DTB_SOURCE
1276	string "Built-in device tree source"
1277	depends on BUILTIN_DTB
1278	help
1279	  DTS file path (without suffix, relative to arch/riscv/boot/dts)
1280	  for the DTS file that will be used to produce the DTB linked into the
1281	  kernel.
1282
1283endmenu # "Boot options"
1284
1285config PORTABLE
1286	bool
1287	default !NONPORTABLE
1288	select EFI
1289	select MMU
1290	select OF
1291
1292config ARCH_PROC_KCORE_TEXT
1293	def_bool y
1294
1295menu "Power management options"
1296
1297source "kernel/power/Kconfig"
1298
1299config ARCH_HIBERNATION_POSSIBLE
1300	def_bool y
1301
1302config ARCH_HIBERNATION_HEADER
1303	def_bool HIBERNATION
1304
1305config ARCH_SUSPEND_POSSIBLE
1306	def_bool y
1307
1308endmenu # "Power management options"
1309
1310menu "CPU Power Management"
1311
1312source "drivers/cpuidle/Kconfig"
1313
1314source "drivers/cpufreq/Kconfig"
1315
1316endmenu # "CPU Power Management"
1317
1318source "arch/riscv/kvm/Kconfig"
1319
1320source "drivers/acpi/Kconfig"
1321