xref: /openbmc/linux/arch/riscv/Kconfig (revision 2f164822)
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_MULTI_HANDLER
67	select GENERIC_IRQ_SHOW
68	select GENERIC_IRQ_SHOW_LEVEL
69	select GENERIC_LIB_DEVMEM_IS_ALLOWED
70	select GENERIC_PCI_IOMAP
71	select GENERIC_PTDUMP if MMU
72	select GENERIC_SCHED_CLOCK
73	select GENERIC_SMP_IDLE_THREAD
74	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
75	select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO
76	select HARDIRQS_SW_RESEND
77	select HAVE_ARCH_AUDITSYSCALL
78	select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP
79	select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL
80	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
81	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
82	select HAVE_ARCH_KASAN if MMU && 64BIT
83	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
84	select HAVE_ARCH_KFENCE if MMU && 64BIT
85	select HAVE_ARCH_KGDB if !XIP_KERNEL
86	select HAVE_ARCH_KGDB_QXFER_PKT
87	select HAVE_ARCH_MMAP_RND_BITS if MMU
88	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
89	select HAVE_ARCH_SECCOMP_FILTER
90	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
91	select HAVE_ARCH_TRACEHOOK
92	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
93	select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
94	select HAVE_ASM_MODVERSIONS
95	select HAVE_CONTEXT_TRACKING_USER
96	select HAVE_DEBUG_KMEMLEAK
97	select HAVE_DMA_CONTIGUOUS if MMU
98	select HAVE_EBPF_JIT if MMU
99	select HAVE_FUNCTION_ARG_ACCESS_API
100	select HAVE_FUNCTION_ERROR_INJECTION
101	select HAVE_GCC_PLUGINS
102	select HAVE_GENERIC_VDSO if MMU && 64BIT
103	select HAVE_IRQ_TIME_ACCOUNTING
104	select HAVE_KPROBES if !XIP_KERNEL
105	select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
106	select HAVE_KRETPROBES if !XIP_KERNEL
107	select HAVE_RETHOOK if !XIP_KERNEL
108	select HAVE_MOVE_PMD
109	select HAVE_MOVE_PUD
110	select HAVE_PCI
111	select HAVE_PERF_EVENTS
112	select HAVE_PERF_REGS
113	select HAVE_PERF_USER_STACK_DUMP
114	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
115	select HAVE_REGS_AND_STACK_ACCESS_API
116	select HAVE_RSEQ
117	select HAVE_STACKPROTECTOR
118	select HAVE_SYSCALL_TRACEPOINTS
119	select IRQ_DOMAIN
120	select IRQ_FORCED_THREADING
121	select MODULES_USE_ELF_RELA if MODULES
122	select MODULE_SECTIONS if MODULES
123	select OF
124	select OF_DMA_DEFAULT_COHERENT
125	select OF_EARLY_FLATTREE
126	select OF_IRQ
127	select PCI_DOMAINS_GENERIC if PCI
128	select PCI_MSI if PCI
129	select RISCV_ALTERNATIVE if !XIP_KERNEL
130	select RISCV_INTC
131	select RISCV_TIMER if RISCV_SBI
132	select SIFIVE_PLIC
133	select SPARSE_IRQ
134	select SYSCTL_EXCEPTION_TRACE
135	select THREAD_INFO_IN_TASK
136	select TRACE_IRQFLAGS_SUPPORT
137	select UACCESS_MEMCPY if !MMU
138	select ZONE_DMA32 if 64BIT
139	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
140	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
141	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
142	select HAVE_FUNCTION_GRAPH_TRACER
143	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
144
145config ARCH_MMAP_RND_BITS_MIN
146	default 18 if 64BIT
147	default 8
148
149config ARCH_MMAP_RND_COMPAT_BITS_MIN
150	default 8
151
152# max bits determined by the following formula:
153#  VA_BITS - PAGE_SHIFT - 3
154config ARCH_MMAP_RND_BITS_MAX
155	default 24 if 64BIT # SV39 based
156	default 17
157
158config ARCH_MMAP_RND_COMPAT_BITS_MAX
159	default 17
160
161# set if we run in machine mode, cleared if we run in supervisor mode
162config RISCV_M_MODE
163	bool
164	default !MMU
165
166# set if we are running in S-mode and can use SBI calls
167config RISCV_SBI
168	bool
169	depends on !RISCV_M_MODE
170	default y
171
172config MMU
173	bool "MMU-based Paged Memory Management Support"
174	default y
175	help
176	  Select if you want MMU-based virtualised addressing space
177	  support by paged memory management. If unsure, say 'Y'.
178
179config PAGE_OFFSET
180	hex
181	default 0xC0000000 if 32BIT
182	default 0x80000000 if 64BIT && !MMU
183	default 0xff60000000000000 if 64BIT
184
185config KASAN_SHADOW_OFFSET
186	hex
187	depends on KASAN_GENERIC
188	default 0xdfffffff00000000 if 64BIT
189	default 0xffffffff if 32BIT
190
191config ARCH_FLATMEM_ENABLE
192	def_bool !NUMA
193
194config ARCH_SPARSEMEM_ENABLE
195	def_bool y
196	depends on MMU
197	select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
198	select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
199
200config ARCH_SELECT_MEMORY_MODEL
201	def_bool ARCH_SPARSEMEM_ENABLE
202
203config ARCH_SUPPORTS_UPROBES
204	def_bool y
205
206config STACKTRACE_SUPPORT
207	def_bool y
208
209config GENERIC_BUG
210	def_bool y
211	depends on BUG
212	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
213
214config GENERIC_BUG_RELATIVE_POINTERS
215	bool
216
217config GENERIC_CALIBRATE_DELAY
218	def_bool y
219
220config GENERIC_CSUM
221	def_bool y
222
223config GENERIC_HWEIGHT
224	def_bool y
225
226config FIX_EARLYCON_MEM
227	def_bool MMU
228
229config PGTABLE_LEVELS
230	int
231	default 5 if 64BIT
232	default 2
233
234config LOCKDEP_SUPPORT
235	def_bool y
236
237config RISCV_DMA_NONCOHERENT
238	bool
239	select ARCH_HAS_DMA_PREP_COHERENT
240	select ARCH_HAS_SETUP_DMA_OPS
241	select ARCH_HAS_SYNC_DMA_FOR_CPU
242	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
243	select DMA_DIRECT_REMAP
244
245config AS_HAS_INSN
246	def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero)
247
248source "arch/riscv/Kconfig.socs"
249source "arch/riscv/Kconfig.erratas"
250
251menu "Platform type"
252
253config NONPORTABLE
254	bool "Allow configurations that result in non-portable kernels"
255	help
256	  RISC-V kernel binaries are compatible between all known systems
257	  whenever possible, but there are some use cases that can only be
258	  satisfied by configurations that result in kernel binaries that are
259	  not portable between systems.
260
261	  Selecting N does not guarantee kernels will be portable to all known
262	  systems.  Selecting any of the options guarded by NONPORTABLE will
263	  result in kernel binaries that are unlikely to be portable between
264	  systems.
265
266	  If unsure, say N.
267
268choice
269	prompt "Base ISA"
270	default ARCH_RV64I
271	help
272	  This selects the base ISA that this kernel will target and must match
273	  the target platform.
274
275config ARCH_RV32I
276	bool "RV32I"
277	depends on NONPORTABLE
278	select 32BIT
279	select GENERIC_LIB_ASHLDI3
280	select GENERIC_LIB_ASHRDI3
281	select GENERIC_LIB_LSHRDI3
282	select GENERIC_LIB_UCMPDI2
283	select MMU
284
285config ARCH_RV64I
286	bool "RV64I"
287	select 64BIT
288	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
289	select SWIOTLB if MMU
290
291endchoice
292
293# We must be able to map all physical memory into the kernel, but the compiler
294# is still a bit more efficient when generating code if it's setup in a manner
295# such that it can only map 2GiB of memory.
296choice
297	prompt "Kernel Code Model"
298	default CMODEL_MEDLOW if 32BIT
299	default CMODEL_MEDANY if 64BIT
300
301	config CMODEL_MEDLOW
302		bool "medium low code model"
303	config CMODEL_MEDANY
304		bool "medium any code model"
305endchoice
306
307config MODULE_SECTIONS
308	bool
309	select HAVE_MOD_ARCH_SPECIFIC
310
311config SMP
312	bool "Symmetric Multi-Processing"
313	help
314	  This enables support for systems with more than one CPU.  If
315	  you say N here, the kernel will run on single and
316	  multiprocessor machines, but will use only one CPU of a
317	  multiprocessor machine. If you say Y here, the kernel will run
318	  on many, but not all, single processor machines. On a single
319	  processor machine, the kernel will run faster if you say N
320	  here.
321
322	  If you don't know what to do here, say N.
323
324config NR_CPUS
325	int "Maximum number of CPUs (2-512)"
326	depends on SMP
327	range 2 512 if !RISCV_SBI_V01
328	range 2 32 if RISCV_SBI_V01 && 32BIT
329	range 2 64 if RISCV_SBI_V01 && 64BIT
330	default "32" if 32BIT
331	default "64" if 64BIT
332
333config HOTPLUG_CPU
334	bool "Support for hot-pluggable CPUs"
335	depends on SMP
336	select GENERIC_IRQ_MIGRATION
337	help
338
339	  Say Y here to experiment with turning CPUs off and on.  CPUs
340	  can be controlled through /sys/devices/system/cpu.
341
342	  Say N if you want to disable CPU hotplug.
343
344choice
345	prompt "CPU Tuning"
346	default TUNE_GENERIC
347
348config TUNE_GENERIC
349	bool "generic"
350
351endchoice
352
353# Common NUMA Features
354config NUMA
355	bool "NUMA Memory Allocation and Scheduler Support"
356	depends on SMP && MMU
357	select ARCH_SUPPORTS_NUMA_BALANCING
358	select GENERIC_ARCH_NUMA
359	select NEED_PER_CPU_EMBED_FIRST_CHUNK
360	select OF_NUMA
361	select USE_PERCPU_NUMA_NODE_ID
362	help
363	  Enable NUMA (Non-Uniform Memory Access) support.
364
365	  The kernel will try to allocate memory used by a CPU on the
366	  local memory of the CPU and add some more NUMA awareness to the kernel.
367
368config NODES_SHIFT
369	int "Maximum NUMA Nodes (as a power of 2)"
370	range 1 10
371	default "2"
372	depends on NUMA
373	help
374	  Specify the maximum number of NUMA Nodes available on the target
375	  system.  Increases memory reserved to accommodate various tables.
376
377config RISCV_ALTERNATIVE
378	bool
379	depends on !XIP_KERNEL
380	help
381	  This Kconfig allows the kernel to automatically patch the
382	  errata required by the execution platform at run time. The
383	  code patching is performed once in the boot stages. It means
384	  that the overhead from this mechanism is just taken once.
385
386config RISCV_ALTERNATIVE_EARLY
387	bool
388	depends on RISCV_ALTERNATIVE
389	help
390	  Allows early patching of the kernel for special errata
391
392config RISCV_ISA_C
393	bool "Emit compressed instructions when building Linux"
394	default y
395	help
396	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
397	  when building Linux, which results in compressed instructions in the
398	  Linux binary.
399
400	  If you don't know what to do here, say Y.
401
402config RISCV_ISA_SVPBMT
403	bool "SVPBMT extension support"
404	depends on 64BIT && MMU
405	depends on RISCV_ALTERNATIVE
406	default y
407	help
408	   Adds support to dynamically detect the presence of the SVPBMT
409	   ISA-extension (Supervisor-mode: page-based memory types) and
410	   enable its usage.
411
412	   The memory type for a page contains a combination of attributes
413	   that indicate the cacheability, idempotency, and ordering
414	   properties for access to that page.
415
416	   The SVPBMT extension is only available on 64Bit cpus.
417
418	   If you don't know what to do here, say Y.
419
420config TOOLCHAIN_HAS_ZBB
421	bool
422	default y
423	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb)
424	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb)
425	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900
426	depends on AS_IS_GNU
427
428config RISCV_ISA_ZBB
429	bool "Zbb extension support for bit manipulation instructions"
430	depends on TOOLCHAIN_HAS_ZBB
431	depends on MMU
432	depends on RISCV_ALTERNATIVE
433	default y
434	help
435	   Adds support to dynamically detect the presence of the ZBB
436	   extension (basic bit manipulation) and enable its usage.
437
438	   The Zbb extension provides instructions to accelerate a number
439	   of bit-specific operations (count bit population, sign extending,
440	   bitrotation, etc).
441
442	   If you don't know what to do here, say Y.
443
444config RISCV_ISA_ZICBOM
445	bool "Zicbom extension support for non-coherent DMA operation"
446	depends on MMU
447	depends on RISCV_ALTERNATIVE
448	default y
449	select RISCV_DMA_NONCOHERENT
450	help
451	   Adds support to dynamically detect the presence of the ZICBOM
452	   extension (Cache Block Management Operations) and enable its
453	   usage.
454
455	   The Zicbom extension can be used to handle for example
456	   non-coherent DMA support on devices that need it.
457
458	   If you don't know what to do here, say Y.
459
460config TOOLCHAIN_HAS_ZIHINTPAUSE
461	bool
462	default y
463	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause)
464	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause)
465	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600
466
467config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
468	def_bool y
469	# https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc
470	depends on AS_IS_GNU && AS_VERSION >= 23800
471	help
472	  Newer binutils versions default to ISA spec version 20191213 which
473	  moves some instructions from the I extension to the Zicsr and Zifencei
474	  extensions.
475
476config TOOLCHAIN_NEEDS_OLD_ISA_SPEC
477	def_bool y
478	depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI
479	# https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16
480	depends on CC_IS_CLANG && CLANG_VERSION < 170000
481	help
482	  Certain versions of clang do not support zicsr and zifencei via -march
483	  but newer versions of binutils require it for the reasons noted in the
484	  help text of CONFIG_TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI. This
485	  option causes an older ISA spec compatible with these older versions
486	  of clang to be passed to GAS, which has the same result as passing zicsr
487	  and zifencei to -march.
488
489config FPU
490	bool "FPU support"
491	default y
492	help
493	  Say N here if you want to disable all floating-point related procedure
494	  in the kernel.
495
496	  If you don't know what to do here, say Y.
497
498endmenu # "Platform type"
499
500menu "Kernel features"
501
502source "kernel/Kconfig.hz"
503
504config RISCV_SBI_V01
505	bool "SBI v0.1 support"
506	depends on RISCV_SBI
507	help
508	  This config allows kernel to use SBI v0.1 APIs. This will be
509	  deprecated in future once legacy M-mode software are no longer in use.
510
511config RISCV_BOOT_SPINWAIT
512	bool "Spinwait booting method"
513	depends on SMP
514	default y if RISCV_SBI_V01 || RISCV_M_MODE
515	help
516	  This enables support for booting Linux via spinwait method. In the
517	  spinwait method, all cores randomly jump to Linux. One of the cores
518	  gets chosen via lottery and all other keep spinning on a percpu
519	  variable. This method cannot support CPU hotplug and sparse hartid
520	  scheme. It should be only enabled for M-mode Linux or platforms relying
521	  on older firmware without SBI HSM extension. All other platforms should
522	  rely on ordered booting via SBI HSM extension which gets chosen
523	  dynamically at runtime if the firmware supports it.
524
525	  Since spinwait is incompatible with sparse hart IDs, it requires
526	  NR_CPUS be large enough to contain the physical hart ID of the first
527	  hart to enter Linux.
528
529	  If unsure what to do here, say N.
530
531config KEXEC
532	bool "Kexec system call"
533	depends on MMU
534	select HOTPLUG_CPU if SMP
535	select KEXEC_CORE
536	help
537	  kexec is a system call that implements the ability to shutdown your
538	  current kernel, and to start another kernel. It is like a reboot
539	  but it is independent of the system firmware. And like a reboot
540	  you can start any kernel with it, not just Linux.
541
542	  The name comes from the similarity to the exec system call.
543
544config KEXEC_FILE
545	bool "kexec file based systmem call"
546	depends on 64BIT && MMU
547	select HAVE_IMA_KEXEC if IMA
548	select KEXEC_CORE
549	select KEXEC_ELF
550	help
551	  This is new version of kexec system call. This system call is
552	  file based and takes file descriptors as system call argument
553	  for kernel and initramfs as opposed to list of segments as
554	  accepted by previous system call.
555
556	  If you don't know what to do here, say Y.
557
558config ARCH_HAS_KEXEC_PURGATORY
559	def_bool KEXEC_FILE
560	depends on CRYPTO=y
561	depends on CRYPTO_SHA256=y
562
563config CRASH_DUMP
564	bool "Build kdump crash kernel"
565	help
566	  Generate crash dump after being started by kexec. This should
567	  be normally only set in special crash dump kernels which are
568	  loaded in the main kernel with kexec-tools into a specially
569	  reserved region and then later executed after a crash by
570	  kdump/kexec.
571
572	  For more details see Documentation/admin-guide/kdump/kdump.rst
573
574config COMPAT
575	bool "Kernel support for 32-bit U-mode"
576	default 64BIT
577	depends on 64BIT && MMU
578	help
579	  This option enables support for a 32-bit U-mode running under a 64-bit
580	  kernel at S-mode. riscv32-specific components such as system calls,
581	  the user helper functions (vdso), signal rt_frame functions and the
582	  ptrace interface are handled appropriately by the kernel.
583
584	  If you want to execute 32-bit userspace applications, say Y.
585
586endmenu # "Kernel features"
587
588menu "Boot options"
589
590config CMDLINE
591	string "Built-in kernel command line"
592	help
593	  For most platforms, the arguments for the kernel's command line
594	  are provided at run-time, during boot. However, there are cases
595	  where either no arguments are being provided or the provided
596	  arguments are insufficient or even invalid.
597
598	  When that occurs, it is possible to define a built-in command
599	  line here and choose how the kernel should use it later on.
600
601choice
602	prompt "Built-in command line usage" if CMDLINE != ""
603	default CMDLINE_FALLBACK
604	help
605	  Choose how the kernel will handle the provided built-in command
606	  line.
607
608config CMDLINE_FALLBACK
609	bool "Use bootloader kernel arguments if available"
610	help
611	  Use the built-in command line as fallback in case we get nothing
612	  during boot. This is the default behaviour.
613
614config CMDLINE_EXTEND
615	bool "Extend bootloader kernel arguments"
616	help
617	  The command-line arguments provided during boot will be
618	  appended to the built-in command line. This is useful in
619	  cases where the provided arguments are insufficient and
620	  you don't want to or cannot modify them.
621
622config CMDLINE_FORCE
623	bool "Always use the default kernel command string"
624	help
625	  Always use the built-in command line, even if we get one during
626	  boot. This is useful in case you need to override the provided
627	  command line on systems where you don't have or want control
628	  over it.
629
630endchoice
631
632config EFI_STUB
633	bool
634
635config EFI
636	bool "UEFI runtime support"
637	depends on OF && !XIP_KERNEL
638	depends on MMU
639	default y
640	select EFI_GENERIC_STUB
641	select EFI_PARAMS_FROM_FDT
642	select EFI_RUNTIME_WRAPPERS
643	select EFI_STUB
644	select LIBFDT
645	select RISCV_ISA_C
646	select UCS2_STRING
647	help
648	  This option provides support for runtime services provided
649	  by UEFI firmware (such as non-volatile variables, realtime
650	  clock, and platform reset). A UEFI stub is also provided to
651	  allow the kernel to be booted as an EFI application. This
652	  is only useful on systems that have UEFI firmware.
653
654config CC_HAVE_STACKPROTECTOR_TLS
655	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
656
657config STACKPROTECTOR_PER_TASK
658	def_bool y
659	depends on !RANDSTRUCT
660	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
661
662config PHYS_RAM_BASE_FIXED
663	bool "Explicitly specified physical RAM address"
664	depends on NONPORTABLE
665	default n
666
667config PHYS_RAM_BASE
668	hex "Platform Physical RAM address"
669	depends on PHYS_RAM_BASE_FIXED
670	default "0x80000000"
671	help
672	  This is the physical address of RAM in the system. It has to be
673	  explicitly specified to run early relocations of read-write data
674	  from flash to RAM.
675
676config XIP_KERNEL
677	bool "Kernel Execute-In-Place from ROM"
678	depends on MMU && SPARSEMEM && NONPORTABLE
679	# This prevents XIP from being enabled by all{yes,mod}config, which
680	# fail to build since XIP doesn't support large kernels.
681	depends on !COMPILE_TEST
682	select PHYS_RAM_BASE_FIXED
683	help
684	  Execute-In-Place allows the kernel to run from non-volatile storage
685	  directly addressable by the CPU, such as NOR flash. This saves RAM
686	  space since the text section of the kernel is not loaded from flash
687	  to RAM.  Read-write sections, such as the data section and stack,
688	  are still copied to RAM.  The XIP kernel is not compressed since
689	  it has to run directly from flash, so it will take more space to
690	  store it.  The flash address used to link the kernel object files,
691	  and for storing it, is configuration dependent. Therefore, if you
692	  say Y here, you must know the proper physical address where to
693	  store the kernel image depending on your own flash memory usage.
694
695	  Also note that the make target becomes "make xipImage" rather than
696	  "make zImage" or "make Image".  The final kernel binary to put in
697	  ROM memory will be arch/riscv/boot/xipImage.
698
699	  SPARSEMEM is required because the kernel text and rodata that are
700	  flash resident are not backed by memmap, then any attempt to get
701	  a struct page on those regions will trigger a fault.
702
703	  If unsure, say N.
704
705config XIP_PHYS_ADDR
706	hex "XIP Kernel Physical Location"
707	depends on XIP_KERNEL
708	default "0x21000000"
709	help
710	  This is the physical address in your flash memory the kernel will
711	  be linked for and stored to.  This address is dependent on your
712	  own flash usage.
713
714endmenu # "Boot options"
715
716config BUILTIN_DTB
717	bool
718	depends on OF && NONPORTABLE
719	default y if XIP_KERNEL
720
721config PORTABLE
722	bool
723	default !NONPORTABLE
724	select EFI
725	select MMU
726	select OF
727
728menu "Power management options"
729
730source "kernel/power/Kconfig"
731
732endmenu # "Power management options"
733
734menu "CPU Power Management"
735
736source "drivers/cpuidle/Kconfig"
737
738source "drivers/cpufreq/Kconfig"
739
740endmenu # "CPU Power Management"
741
742source "arch/riscv/kvm/Kconfig"
743