xref: /linux/arch/riscv/Kconfig (revision 8ccd54fe45713cd458015b5b08d6098545e70543)
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 ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
16	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
17	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
18	select ARCH_HAS_BINFMT_FLAT
19	select ARCH_HAS_CURRENT_STACK_POINTER
20	select ARCH_HAS_DEBUG_VIRTUAL if MMU
21	select ARCH_HAS_DEBUG_VM_PGTABLE
22	select ARCH_HAS_DEBUG_WX
23	select ARCH_HAS_FORTIFY_SOURCE
24	select ARCH_HAS_GCOV_PROFILE_ALL
25	select ARCH_HAS_GIGANTIC_PAGE
26	select ARCH_HAS_KCOV
27	select ARCH_HAS_MMIOWB
28	select ARCH_HAS_PMEM_API
29	select ARCH_HAS_PTE_SPECIAL
30	select ARCH_HAS_SET_DIRECT_MAP if MMU
31	select ARCH_HAS_SET_MEMORY if MMU
32	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
33	select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
34	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
35	select ARCH_HAS_UBSAN_SANITIZE_ALL
36	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
37	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
38	select ARCH_STACKWALK
39	select ARCH_SUPPORTS_ATOMIC_RMW
40	select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
41	select ARCH_SUPPORTS_HUGETLBFS if MMU
42	select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU
43	select ARCH_USE_MEMTEST
44	select ARCH_USE_QUEUED_RWLOCKS
45	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
46	select ARCH_WANT_FRAME_POINTERS
47	select ARCH_WANT_GENERAL_HUGETLB
48	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
49	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
50	select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL
51	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
52	select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
53	select BUILDTIME_TABLE_SORT if MMU
54	select CLINT_TIMER if !MMU
55	select CLONE_BACKWARDS
56	select COMMON_CLK
57	select CPU_PM if CPU_IDLE
58	select EDAC_SUPPORT
59	select GENERIC_ARCH_TOPOLOGY
60	select GENERIC_ATOMIC64 if !64BIT
61	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
62	select GENERIC_EARLY_IOREMAP
63	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
64	select GENERIC_IDLE_POLL_SETUP
65	select GENERIC_IOREMAP if MMU
66	select GENERIC_IRQ_IPI if SMP
67	select GENERIC_IRQ_IPI_MUX if SMP
68	select GENERIC_IRQ_MULTI_HANDLER
69	select GENERIC_IRQ_SHOW
70	select GENERIC_IRQ_SHOW_LEVEL
71	select GENERIC_LIB_DEVMEM_IS_ALLOWED
72	select GENERIC_PCI_IOMAP
73	select GENERIC_PTDUMP if MMU
74	select GENERIC_SCHED_CLOCK
75	select GENERIC_SMP_IDLE_THREAD
76	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
77	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
78	select HARDIRQS_SW_RESEND
79	select HAS_IOPORT if MMU
80	select HAVE_ARCH_AUDITSYSCALL
81	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
82	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
83	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
84	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
85	select HAVE_ARCH_KASAN if MMU && 64BIT
86	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
87	select HAVE_ARCH_KFENCE if MMU && 64BIT
88	select HAVE_ARCH_KGDB if !XIP_KERNEL
89	select HAVE_ARCH_KGDB_QXFER_PKT
90	select HAVE_ARCH_MMAP_RND_BITS if MMU
91	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
92	select HAVE_ARCH_SECCOMP_FILTER
93	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
94	select HAVE_ARCH_TRACEHOOK
95	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
96	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
97	select HAVE_ASM_MODVERSIONS
98	select HAVE_CONTEXT_TRACKING_USER
99	select HAVE_DEBUG_KMEMLEAK
100	select HAVE_DMA_CONTIGUOUS if MMU
101	select HAVE_EBPF_JIT if MMU
102	select HAVE_FUNCTION_ARG_ACCESS_API
103	select HAVE_FUNCTION_ERROR_INJECTION
104	select HAVE_GCC_PLUGINS
105	select HAVE_GENERIC_VDSO if MMU && 64BIT
106	select HAVE_IRQ_TIME_ACCOUNTING
107	select HAVE_KPROBES if !XIP_KERNEL
108	select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
109	select HAVE_KRETPROBES if !XIP_KERNEL
110	select HAVE_RETHOOK if !XIP_KERNEL
111	select HAVE_MOVE_PMD
112	select HAVE_MOVE_PUD
113	select HAVE_PCI
114	select HAVE_PERF_EVENTS
115	select HAVE_PERF_REGS
116	select HAVE_PERF_USER_STACK_DUMP
117	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
118	select HAVE_REGS_AND_STACK_ACCESS_API
119	select HAVE_RSEQ
120	select HAVE_STACKPROTECTOR
121	select HAVE_SYSCALL_TRACEPOINTS
122	select IRQ_DOMAIN
123	select IRQ_FORCED_THREADING
124	select MODULES_USE_ELF_RELA if MODULES
125	select MODULE_SECTIONS if MODULES
126	select OF
127	select OF_DMA_DEFAULT_COHERENT
128	select OF_EARLY_FLATTREE
129	select OF_IRQ
130	select PCI_DOMAINS_GENERIC if PCI
131	select PCI_MSI if PCI
132	select RISCV_ALTERNATIVE if !XIP_KERNEL
133	select RISCV_INTC
134	select RISCV_TIMER if RISCV_SBI
135	select SIFIVE_PLIC
136	select SPARSE_IRQ
137	select SYSCTL_EXCEPTION_TRACE
138	select THREAD_INFO_IN_TASK
139	select TRACE_IRQFLAGS_SUPPORT
140	select UACCESS_MEMCPY if !MMU
141	select ZONE_DMA32 if 64BIT
142	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
143	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
144	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
145	select HAVE_FUNCTION_GRAPH_TRACER
146	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
147
148config ARCH_MMAP_RND_BITS_MIN
149	default 18 if 64BIT
150	default 8
151
152config ARCH_MMAP_RND_COMPAT_BITS_MIN
153	default 8
154
155# max bits determined by the following formula:
156#  VA_BITS - PAGE_SHIFT - 3
157config ARCH_MMAP_RND_BITS_MAX
158	default 24 if 64BIT # SV39 based
159	default 17
160
161config ARCH_MMAP_RND_COMPAT_BITS_MAX
162	default 17
163
164# set if we run in machine mode, cleared if we run in supervisor mode
165config RISCV_M_MODE
166	bool
167	default !MMU
168
169# set if we are running in S-mode and can use SBI calls
170config RISCV_SBI
171	bool
172	depends on !RISCV_M_MODE
173	default y
174
175config MMU
176	bool "MMU-based Paged Memory Management Support"
177	default y
178	help
179	  Select if you want MMU-based virtualised addressing space
180	  support by paged memory management. If unsure, say 'Y'.
181
182config PAGE_OFFSET
183	hex
184	default 0xC0000000 if 32BIT
185	default 0x80000000 if 64BIT && !MMU
186	default 0xff60000000000000 if 64BIT
187
188config KASAN_SHADOW_OFFSET
189	hex
190	depends on KASAN_GENERIC
191	default 0xdfffffff00000000 if 64BIT
192	default 0xffffffff if 32BIT
193
194config ARCH_FLATMEM_ENABLE
195	def_bool !NUMA
196
197config ARCH_SPARSEMEM_ENABLE
198	def_bool y
199	depends on MMU
200	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
201	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
202
203config ARCH_SELECT_MEMORY_MODEL
204	def_bool ARCH_SPARSEMEM_ENABLE
205
206config ARCH_SUPPORTS_UPROBES
207	def_bool y
208
209config STACKTRACE_SUPPORT
210	def_bool y
211
212config GENERIC_BUG
213	def_bool y
214	depends on BUG
215	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
216
217config GENERIC_BUG_RELATIVE_POINTERS
218	bool
219
220config GENERIC_CALIBRATE_DELAY
221	def_bool y
222
223config GENERIC_CSUM
224	def_bool y
225
226config GENERIC_HWEIGHT
227	def_bool y
228
229config FIX_EARLYCON_MEM
230	def_bool MMU
231
232config PGTABLE_LEVELS
233	int
234	default 5 if 64BIT
235	default 2
236
237config LOCKDEP_SUPPORT
238	def_bool y
239
240config RISCV_DMA_NONCOHERENT
241	bool
242	select ARCH_HAS_DMA_PREP_COHERENT
243	select ARCH_HAS_SETUP_DMA_OPS
244	select ARCH_HAS_SYNC_DMA_FOR_CPU
245	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
246	select DMA_DIRECT_REMAP
247
248config AS_HAS_INSN
249	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
250
251source "arch/riscv/Kconfig.socs"
252source "arch/riscv/Kconfig.erratas"
253
254menu "Platform type"
255
256config NONPORTABLE
257	bool "Allow configurations that result in non-portable kernels"
258	help
259	  RISC-V kernel binaries are compatible between all known systems
260	  whenever possible, but there are some use cases that can only be
261	  satisfied by configurations that result in kernel binaries that are
262	  not portable between systems.
263
264	  Selecting N does not guarantee kernels will be portable to all known
265	  systems.  Selecting any of the options guarded by NONPORTABLE will
266	  result in kernel binaries that are unlikely to be portable between
267	  systems.
268
269	  If unsure, say N.
270
271choice
272	prompt "Base ISA"
273	default ARCH_RV64I
274	help
275	  This selects the base ISA that this kernel will target and must match
276	  the target platform.
277
278config ARCH_RV32I
279	bool "RV32I"
280	depends on NONPORTABLE
281	select 32BIT
282	select GENERIC_LIB_ASHLDI3
283	select GENERIC_LIB_ASHRDI3
284	select GENERIC_LIB_LSHRDI3
285	select GENERIC_LIB_UCMPDI2
286	select MMU
287
288config ARCH_RV64I
289	bool "RV64I"
290	select 64BIT
291	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
292	select SWIOTLB if MMU
293
294endchoice
295
296# We must be able to map all physical memory into the kernel, but the compiler
297# is still a bit more efficient when generating code if it's setup in a manner
298# such that it can only map 2GiB of memory.
299choice
300	prompt "Kernel Code Model"
301	default CMODEL_MEDLOW if 32BIT
302	default CMODEL_MEDANY if 64BIT
303
304	config CMODEL_MEDLOW
305		bool "medium low code model"
306	config CMODEL_MEDANY
307		bool "medium any code model"
308endchoice
309
310config MODULE_SECTIONS
311	bool
312	select HAVE_MOD_ARCH_SPECIFIC
313
314config SMP
315	bool "Symmetric Multi-Processing"
316	help
317	  This enables support for systems with more than one CPU.  If
318	  you say N here, the kernel will run on single and
319	  multiprocessor machines, but will use only one CPU of a
320	  multiprocessor machine. If you say Y here, the kernel will run
321	  on many, but not all, single processor machines. On a single
322	  processor machine, the kernel will run faster if you say N
323	  here.
324
325	  If you don't know what to do here, say N.
326
327config NR_CPUS
328	int "Maximum number of CPUs (2-512)"
329	depends on SMP
330	range 2 512 if !RISCV_SBI_V01
331	range 2 32 if RISCV_SBI_V01 && 32BIT
332	range 2 64 if RISCV_SBI_V01 && 64BIT
333	default "32" if 32BIT
334	default "64" if 64BIT
335
336config HOTPLUG_CPU
337	bool "Support for hot-pluggable CPUs"
338	depends on SMP
339	select GENERIC_IRQ_MIGRATION
340	help
341
342	  Say Y here to experiment with turning CPUs off and on.  CPUs
343	  can be controlled through /sys/devices/system/cpu.
344
345	  Say N if you want to disable CPU hotplug.
346
347choice
348	prompt "CPU Tuning"
349	default TUNE_GENERIC
350
351config TUNE_GENERIC
352	bool "generic"
353
354endchoice
355
356# Common NUMA Features
357config NUMA
358	bool "NUMA Memory Allocation and Scheduler Support"
359	depends on SMP && MMU
360	select ARCH_SUPPORTS_NUMA_BALANCING
361	select GENERIC_ARCH_NUMA
362	select NEED_PER_CPU_EMBED_FIRST_CHUNK
363	select OF_NUMA
364	select USE_PERCPU_NUMA_NODE_ID
365	help
366	  Enable NUMA (Non-Uniform Memory Access) support.
367
368	  The kernel will try to allocate memory used by a CPU on the
369	  local memory of the CPU and add some more NUMA awareness to the kernel.
370
371config NODES_SHIFT
372	int "Maximum NUMA Nodes (as a power of 2)"
373	range 1 10
374	default "2"
375	depends on NUMA
376	help
377	  Specify the maximum number of NUMA Nodes available on the target
378	  system.  Increases memory reserved to accommodate various tables.
379
380config RISCV_ALTERNATIVE
381	bool
382	depends on !XIP_KERNEL
383	help
384	  This Kconfig allows the kernel to automatically patch the
385	  errata required by the execution platform at run time. The
386	  code patching is performed once in the boot stages. It means
387	  that the overhead from this mechanism is just taken once.
388
389config RISCV_ALTERNATIVE_EARLY
390	bool
391	depends on RISCV_ALTERNATIVE
392	help
393	  Allows early patching of the kernel for special errata
394
395config RISCV_ISA_C
396	bool "Emit compressed instructions when building Linux"
397	default y
398	help
399	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
400	  when building Linux, which results in compressed instructions in the
401	  Linux binary.
402
403	  If you don't know what to do here, say Y.
404
405config RISCV_ISA_SVPBMT
406	bool "SVPBMT extension support"
407	depends on 64BIT && MMU
408	depends on RISCV_ALTERNATIVE
409	default y
410	help
411	   Adds support to dynamically detect the presence of the SVPBMT
412	   ISA-extension (Supervisor-mode: page-based memory types) and
413	   enable its usage.
414
415	   The memory type for a page contains a combination of attributes
416	   that indicate the cacheability, idempotency, and ordering
417	   properties for access to that page.
418
419	   The SVPBMT extension is only available on 64Bit cpus.
420
421	   If you don't know what to do here, say Y.
422
423config TOOLCHAIN_HAS_ZBB
424	bool
425	default y
426	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
427	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
428	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
429	depends on AS_IS_GNU
430
431config RISCV_ISA_ZBB
432	bool "Zbb extension support for bit manipulation instructions"
433	depends on TOOLCHAIN_HAS_ZBB
434	depends on MMU
435	depends on RISCV_ALTERNATIVE
436	default y
437	help
438	   Adds support to dynamically detect the presence of the ZBB
439	   extension (basic bit manipulation) and enable its usage.
440
441	   The Zbb extension provides instructions to accelerate a number
442	   of bit-specific operations (count bit population, sign extending,
443	   bitrotation, etc).
444
445	   If you don't know what to do here, say Y.
446
447config RISCV_ISA_ZICBOM
448	bool "Zicbom extension support for non-coherent DMA operation"
449	depends on MMU
450	depends on RISCV_ALTERNATIVE
451	default y
452	select RISCV_DMA_NONCOHERENT
453	help
454	   Adds support to dynamically detect the presence of the ZICBOM
455	   extension (Cache Block Management Operations) and enable its
456	   usage.
457
458	   The Zicbom extension can be used to handle for example
459	   non-coherent DMA support on devices that need it.
460
461	   If you don't know what to do here, say Y.
462
463config TOOLCHAIN_HAS_ZIHINTPAUSE
464	bool
465	default y
466	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause)
467	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause)
468	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600
469
470config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
471	def_bool y
472	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
473	depends on AS_IS_GNU && AS_VERSION >= 23800
474	help
475	  Newer binutils versions default to ISA spec version 20191213 which
476	  moves some instructions from the I extension to the Zicsr and Zifencei
477	  extensions.
478
479config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
480	def_bool y
481	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
482	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
483	depends on CC_IS_CLANG && CLANG_VERSION < 170000
484	help
485	  Certain versions of clang do not support zicsr and zifencei via -march
486	  but newer versions of binutils require it for the reasons noted in the
487	  help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
488	  option causes an older ISA spec compatible with these older versions
489	  of clang to be passed to GAS, which has the same result as passing zicsr
490	  and zifencei to -march.
491
492config FPU
493	bool "FPU support"
494	default y
495	help
496	  Say N here if you want to disable all floating-point related procedure
497	  in the kernel.
498
499	  If you don't know what to do here, say Y.
500
501endmenu # "Platform type"
502
503menu "Kernel features"
504
505source "kernel/Kconfig.hz"
506
507config RISCV_SBI_V01
508	bool "SBI v0.1 support"
509	depends on RISCV_SBI
510	help
511	  This config allows kernel to use SBI v0.1 APIs. This will be
512	  deprecated in future once legacy M-mode software are no longer in use.
513
514config RISCV_BOOT_SPINWAIT
515	bool "Spinwait booting method"
516	depends on SMP
517	default y if RISCV_SBI_V01 || RISCV_M_MODE
518	help
519	  This enables support for booting Linux via spinwait method. In the
520	  spinwait method, all cores randomly jump to Linux. One of the cores
521	  gets chosen via lottery and all other keep spinning on a percpu
522	  variable. This method cannot support CPU hotplug and sparse hartid
523	  scheme. It should be only enabled for M-mode Linux or platforms relying
524	  on older firmware without SBI HSM extension. All other platforms should
525	  rely on ordered booting via SBI HSM extension which gets chosen
526	  dynamically at runtime if the firmware supports it.
527
528	  Since spinwait is incompatible with sparse hart IDs, it requires
529	  NR_CPUS be large enough to contain the physical hart ID of the first
530	  hart to enter Linux.
531
532	  If unsure what to do here, say N.
533
534config KEXEC
535	bool "Kexec system call"
536	depends on MMU
537	select HOTPLUG_CPU if SMP
538	select KEXEC_CORE
539	help
540	  kexec is a system call that implements the ability to shutdown your
541	  current kernel, and to start another kernel. It is like a reboot
542	  but it is independent of the system firmware. And like a reboot
543	  you can start any kernel with it, not just Linux.
544
545	  The name comes from the similarity to the exec system call.
546
547config KEXEC_FILE
548	bool "kexec file based systmem call"
549	depends on 64BIT && MMU
550	select HAVE_IMA_KEXEC if IMA
551	select KEXEC_CORE
552	select KEXEC_ELF
553	help
554	  This is new version of kexec system call. This system call is
555	  file based and takes file descriptors as system call argument
556	  for kernel and initramfs as opposed to list of segments as
557	  accepted by previous system call.
558
559	  If you don't know what to do here, say Y.
560
561config ARCH_HAS_KEXEC_PURGATORY
562	def_bool KEXEC_FILE
563	depends on CRYPTO=y
564	depends on CRYPTO_SHA256=y
565
566config CRASH_DUMP
567	bool "Build kdump crash kernel"
568	help
569	  Generate crash dump after being started by kexec. This should
570	  be normally only set in special crash dump kernels which are
571	  loaded in the main kernel with kexec-tools into a specially
572	  reserved region and then later executed after a crash by
573	  kdump/kexec.
574
575	  For more details see Documentation/admin-guide/kdump/kdump.rst
576
577config COMPAT
578	bool "Kernel support for 32-bit U-mode"
579	default 64BIT
580	depends on 64BIT && MMU
581	help
582	  This option enables support for a 32-bit U-mode running under a 64-bit
583	  kernel at S-mode. riscv32-specific components such as system calls,
584	  the user helper functions (vdso), signal rt_frame functions and the
585	  ptrace interface are handled appropriately by the kernel.
586
587	  If you want to execute 32-bit userspace applications, say Y.
588
589endmenu # "Kernel features"
590
591menu "Boot options"
592
593config CMDLINE
594	string "Built-in kernel command line"
595	help
596	  For most platforms, the arguments for the kernel's command line
597	  are provided at run-time, during boot. However, there are cases
598	  where either no arguments are being provided or the provided
599	  arguments are insufficient or even invalid.
600
601	  When that occurs, it is possible to define a built-in command
602	  line here and choose how the kernel should use it later on.
603
604choice
605	prompt "Built-in command line usage" if CMDLINE != ""
606	default CMDLINE_FALLBACK
607	help
608	  Choose how the kernel will handle the provided built-in command
609	  line.
610
611config CMDLINE_FALLBACK
612	bool "Use bootloader kernel arguments if available"
613	help
614	  Use the built-in command line as fallback in case we get nothing
615	  during boot. This is the default behaviour.
616
617config CMDLINE_EXTEND
618	bool "Extend bootloader kernel arguments"
619	help
620	  The command-line arguments provided during boot will be
621	  appended to the built-in command line. This is useful in
622	  cases where the provided arguments are insufficient and
623	  you don't want to or cannot modify them.
624
625config CMDLINE_FORCE
626	bool "Always use the default kernel command string"
627	help
628	  Always use the built-in command line, even if we get one during
629	  boot. This is useful in case you need to override the provided
630	  command line on systems where you don't have or want control
631	  over it.
632
633endchoice
634
635config EFI_STUB
636	bool
637
638config EFI
639	bool "UEFI runtime support"
640	depends on OF && !XIP_KERNEL
641	depends on MMU
642	default y
643	select EFI_GENERIC_STUB
644	select EFI_PARAMS_FROM_FDT
645	select EFI_RUNTIME_WRAPPERS
646	select EFI_STUB
647	select LIBFDT
648	select RISCV_ISA_C
649	select UCS2_STRING
650	help
651	  This option provides support for runtime services provided
652	  by UEFI firmware (such as non-volatile variables, realtime
653	  clock, and platform reset). A UEFI stub is also provided to
654	  allow the kernel to be booted as an EFI application. This
655	  is only useful on systems that have UEFI firmware.
656
657config CC_HAVE_STACKPROTECTOR_TLS
658	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
659
660config STACKPROTECTOR_PER_TASK
661	def_bool y
662	depends on !RANDSTRUCT
663	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
664
665config PHYS_RAM_BASE_FIXED
666	bool "Explicitly specified physical RAM address"
667	depends on NONPORTABLE
668	default n
669
670config PHYS_RAM_BASE
671	hex "Platform Physical RAM address"
672	depends on PHYS_RAM_BASE_FIXED
673	default "0x80000000"
674	help
675	  This is the physical address of RAM in the system. It has to be
676	  explicitly specified to run early relocations of read-write data
677	  from flash to RAM.
678
679config XIP_KERNEL
680	bool "Kernel Execute-In-Place from ROM"
681	depends on MMU && SPARSEMEM && NONPORTABLE
682	# This prevents XIP from being enabled by all{yes,mod}config, which
683	# fail to build since XIP doesn't support large kernels.
684	depends on !COMPILE_TEST
685	select PHYS_RAM_BASE_FIXED
686	help
687	  Execute-In-Place allows the kernel to run from non-volatile storage
688	  directly addressable by the CPU, such as NOR flash. This saves RAM
689	  space since the text section of the kernel is not loaded from flash
690	  to RAM.  Read-write sections, such as the data section and stack,
691	  are still copied to RAM.  The XIP kernel is not compressed since
692	  it has to run directly from flash, so it will take more space to
693	  store it.  The flash address used to link the kernel object files,
694	  and for storing it, is configuration dependent. Therefore, if you
695	  say Y here, you must know the proper physical address where to
696	  store the kernel image depending on your own flash memory usage.
697
698	  Also note that the make target becomes "make xipImage" rather than
699	  "make zImage" or "make Image".  The final kernel binary to put in
700	  ROM memory will be arch/riscv/boot/xipImage.
701
702	  SPARSEMEM is required because the kernel text and rodata that are
703	  flash resident are not backed by memmap, then any attempt to get
704	  a struct page on those regions will trigger a fault.
705
706	  If unsure, say N.
707
708config XIP_PHYS_ADDR
709	hex "XIP Kernel Physical Location"
710	depends on XIP_KERNEL
711	default "0x21000000"
712	help
713	  This is the physical address in your flash memory the kernel will
714	  be linked for and stored to.  This address is dependent on your
715	  own flash usage.
716
717endmenu # "Boot options"
718
719config BUILTIN_DTB
720	bool
721	depends on OF && NONPORTABLE
722	default y if XIP_KERNEL
723
724config PORTABLE
725	bool
726	default !NONPORTABLE
727	select EFI
728	select MMU
729	select OF
730
731menu "Power management options"
732
733source "kernel/power/Kconfig"
734
735endmenu # "Power management options"
736
737menu "CPU Power Management"
738
739source "drivers/cpuidle/Kconfig"
740
741source "drivers/cpufreq/Kconfig"
742
743endmenu # "CPU Power Management"
744
745source "arch/riscv/kvm/Kconfig"
746