xref: /linux/arch/loongarch/Kconfig (revision 17ba9cde11c2bfebbd70867b0a2ac4a22e573379)
1# SPDX-License-Identifier: GPL-2.0
2config LOONGARCH
3	bool
4	default y
5	select ACPI
6	select ACPI_GENERIC_GSI if ACPI
7	select ACPI_MCFG if ACPI
8	select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
9	select ACPI_PPTT if ACPI
10	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
11	select ARCH_BINFMT_ELF_STATE
12	select ARCH_DISABLE_KASAN_INLINE
13	select ARCH_ENABLE_MEMORY_HOTPLUG
14	select ARCH_ENABLE_MEMORY_HOTREMOVE
15	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
16	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
17	select ARCH_HAS_CPU_FINALIZE_INIT
18	select ARCH_HAS_FORTIFY_SOURCE
19	select ARCH_HAS_KCOV
20	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
21	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
22	select ARCH_HAS_PTE_SPECIAL
23	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
24	select ARCH_INLINE_READ_LOCK if !PREEMPTION
25	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
26	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
27	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
28	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
29	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
30	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
31	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
32	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
33	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
34	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
35	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
36	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
37	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
38	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
39	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
40	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
41	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
42	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
43	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
44	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
45	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
46	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
47	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
48	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
49	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
50	select ARCH_KEEP_MEMBLOCK
51	select ARCH_MIGHT_HAVE_PC_PARPORT
52	select ARCH_MIGHT_HAVE_PC_SERIO
53	select ARCH_SPARSEMEM_ENABLE
54	select ARCH_STACKWALK
55	select ARCH_SUPPORTS_ACPI
56	select ARCH_SUPPORTS_ATOMIC_RMW
57	select ARCH_SUPPORTS_HUGETLBFS
58	select ARCH_SUPPORTS_LTO_CLANG
59	select ARCH_SUPPORTS_LTO_CLANG_THIN
60	select ARCH_SUPPORTS_NUMA_BALANCING
61	select ARCH_USE_BUILTIN_BSWAP
62	select ARCH_USE_CMPXCHG_LOCKREF
63	select ARCH_USE_QUEUED_RWLOCKS
64	select ARCH_USE_QUEUED_SPINLOCKS
65	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
66	select ARCH_WANT_LD_ORPHAN_WARN
67	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
68	select ARCH_WANTS_NO_INSTR
69	select BUILDTIME_TABLE_SORT
70	select COMMON_CLK
71	select CPU_PM
72	select EFI
73	select GENERIC_CLOCKEVENTS
74	select GENERIC_CMOS_UPDATE
75	select GENERIC_CPU_AUTOPROBE
76	select GENERIC_CPU_DEVICES
77	select GENERIC_ENTRY
78	select GENERIC_GETTIMEOFDAY
79	select GENERIC_IOREMAP if !ARCH_IOREMAP
80	select GENERIC_IRQ_MULTI_HANDLER
81	select GENERIC_IRQ_PROBE
82	select GENERIC_IRQ_SHOW
83	select GENERIC_LIB_ASHLDI3
84	select GENERIC_LIB_ASHRDI3
85	select GENERIC_LIB_CMPDI2
86	select GENERIC_LIB_LSHRDI3
87	select GENERIC_LIB_UCMPDI2
88	select GENERIC_LIB_DEVMEM_IS_ALLOWED
89	select GENERIC_PCI_IOMAP
90	select GENERIC_SCHED_CLOCK
91	select GENERIC_SMP_IDLE_THREAD
92	select GENERIC_TIME_VSYSCALL
93	select GENERIC_VDSO_TIME_NS
94	select GPIOLIB
95	select HAS_IOPORT
96	select HAVE_ARCH_AUDITSYSCALL
97	select HAVE_ARCH_JUMP_LABEL
98	select HAVE_ARCH_JUMP_LABEL_RELATIVE
99	select HAVE_ARCH_KASAN
100	select HAVE_ARCH_KFENCE
101	select HAVE_ARCH_KGDB if PERF_EVENTS
102	select HAVE_ARCH_MMAP_RND_BITS if MMU
103	select HAVE_ARCH_SECCOMP
104	select HAVE_ARCH_SECCOMP_FILTER
105	select HAVE_ARCH_TRACEHOOK
106	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
107	select HAVE_ASM_MODVERSIONS
108	select HAVE_CONTEXT_TRACKING_USER
109	select HAVE_C_RECORDMCOUNT
110	select HAVE_DEBUG_KMEMLEAK
111	select HAVE_DEBUG_STACKOVERFLOW
112	select HAVE_DMA_CONTIGUOUS
113	select HAVE_DYNAMIC_FTRACE
114	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
115	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
116	select HAVE_DYNAMIC_FTRACE_WITH_REGS
117	select HAVE_EBPF_JIT
118	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
119	select HAVE_EXIT_THREAD
120	select HAVE_FAST_GUP
121	select HAVE_FTRACE_MCOUNT_RECORD
122	select HAVE_FUNCTION_ARG_ACCESS_API
123	select HAVE_FUNCTION_ERROR_INJECTION
124	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
125	select HAVE_FUNCTION_GRAPH_TRACER
126	select HAVE_FUNCTION_TRACER
127	select HAVE_GCC_PLUGINS
128	select HAVE_GENERIC_VDSO
129	select HAVE_HW_BREAKPOINT if PERF_EVENTS
130	select HAVE_IOREMAP_PROT
131	select HAVE_IRQ_EXIT_ON_IRQ_STACK
132	select HAVE_IRQ_TIME_ACCOUNTING
133	select HAVE_KPROBES
134	select HAVE_KPROBES_ON_FTRACE
135	select HAVE_KRETPROBES
136	select HAVE_KVM
137	select HAVE_MOD_ARCH_SPECIFIC
138	select HAVE_NMI
139	select HAVE_PCI
140	select HAVE_PERF_EVENTS
141	select HAVE_PERF_REGS
142	select HAVE_PERF_USER_STACK_DUMP
143	select HAVE_PREEMPT_DYNAMIC_KEY
144	select HAVE_REGS_AND_STACK_ACCESS_API
145	select HAVE_RETHOOK
146	select HAVE_RSEQ
147	select HAVE_RUST
148	select HAVE_SAMPLE_FTRACE_DIRECT
149	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
150	select HAVE_SETUP_PER_CPU_AREA if NUMA
151	select HAVE_STACKPROTECTOR
152	select HAVE_SYSCALL_TRACEPOINTS
153	select HAVE_TIF_NOHZ
154	select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
155	select IRQ_FORCED_THREADING
156	select IRQ_LOONGARCH_CPU
157	select LOCK_MM_AND_FIND_VMA
158	select MMU_GATHER_MERGE_VMAS if MMU
159	select MODULES_USE_ELF_RELA if MODULES
160	select NEED_PER_CPU_EMBED_FIRST_CHUNK
161	select NEED_PER_CPU_PAGE_FIRST_CHUNK
162	select OF
163	select OF_EARLY_FLATTREE
164	select PCI
165	select PCI_DOMAINS_GENERIC
166	select PCI_ECAM if ACPI
167	select PCI_LOONGSON
168	select PCI_MSI_ARCH_FALLBACKS
169	select PCI_QUIRKS
170	select PERF_USE_VMALLOC
171	select RTC_LIB
172	select SMP
173	select SPARSE_IRQ
174	select SYSCTL_ARCH_UNALIGN_ALLOW
175	select SYSCTL_ARCH_UNALIGN_NO_WARN
176	select SYSCTL_EXCEPTION_TRACE
177	select SWIOTLB
178	select TRACE_IRQFLAGS_SUPPORT
179	select USE_PERCPU_NUMA_NODE_ID
180	select USER_STACKTRACE_SUPPORT
181	select ZONE_DMA32
182
183config 32BIT
184	bool
185
186config 64BIT
187	def_bool y
188
189config GENERIC_BUG
190	def_bool y
191	depends on BUG
192
193config GENERIC_BUG_RELATIVE_POINTERS
194	def_bool y
195	depends on GENERIC_BUG
196
197config GENERIC_CALIBRATE_DELAY
198	def_bool y
199
200config GENERIC_CSUM
201	def_bool y
202
203config GENERIC_HWEIGHT
204	def_bool y
205
206config L1_CACHE_SHIFT
207	int
208	default "6"
209
210config LOCKDEP_SUPPORT
211	bool
212	default y
213
214config STACKTRACE_SUPPORT
215	bool
216	default y
217
218# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the
219# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
220# are shared between architectures, and specifically expecting the symbols.
221config MACH_LOONGSON32
222	def_bool 32BIT
223
224config MACH_LOONGSON64
225	def_bool 64BIT
226
227config FIX_EARLYCON_MEM
228	def_bool y
229
230config PAGE_SIZE_4KB
231	bool
232
233config PAGE_SIZE_16KB
234	bool
235
236config PAGE_SIZE_64KB
237	bool
238
239config PGTABLE_2LEVEL
240	bool
241
242config PGTABLE_3LEVEL
243	bool
244
245config PGTABLE_4LEVEL
246	bool
247
248config PGTABLE_LEVELS
249	int
250	default 2 if PGTABLE_2LEVEL
251	default 3 if PGTABLE_3LEVEL
252	default 4 if PGTABLE_4LEVEL
253
254config SCHED_OMIT_FRAME_POINTER
255	bool
256	default y
257
258config AS_HAS_EXPLICIT_RELOCS
259	def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x))
260
261config AS_HAS_FCSR_CLASS
262	def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0)
263
264config AS_HAS_LSX_EXTENSION
265	def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0)
266
267config AS_HAS_LASX_EXTENSION
268	def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0)
269
270config AS_HAS_LBT_EXTENSION
271	def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0)
272
273config AS_HAS_LVZ_EXTENSION
274	def_bool $(as-instr,hvcl 0)
275
276menu "Kernel type and options"
277
278source "kernel/Kconfig.hz"
279
280choice
281	prompt "Page Table Layout"
282	default 16KB_2LEVEL if 32BIT
283	default 16KB_3LEVEL if 64BIT
284	help
285	  Allows choosing the page table layout, which is a combination
286	  of page size and page table levels. The size of virtual memory
287	  address space are determined by the page table layout.
288
289config 4KB_3LEVEL
290	bool "4KB with 3 levels"
291	select PAGE_SIZE_4KB
292	select PGTABLE_3LEVEL
293	help
294	  This option selects 4KB page size with 3 level page tables, which
295	  support a maximum of 39 bits of application virtual memory.
296
297config 4KB_4LEVEL
298	bool "4KB with 4 levels"
299	select PAGE_SIZE_4KB
300	select PGTABLE_4LEVEL
301	help
302	  This option selects 4KB page size with 4 level page tables, which
303	  support a maximum of 48 bits of application virtual memory.
304
305config 16KB_2LEVEL
306	bool "16KB with 2 levels"
307	select PAGE_SIZE_16KB
308	select PGTABLE_2LEVEL
309	help
310	  This option selects 16KB page size with 2 level page tables, which
311	  support a maximum of 36 bits of application virtual memory.
312
313config 16KB_3LEVEL
314	bool "16KB with 3 levels"
315	select PAGE_SIZE_16KB
316	select PGTABLE_3LEVEL
317	help
318	  This option selects 16KB page size with 3 level page tables, which
319	  support a maximum of 47 bits of application virtual memory.
320
321config 64KB_2LEVEL
322	bool "64KB with 2 levels"
323	select PAGE_SIZE_64KB
324	select PGTABLE_2LEVEL
325	help
326	  This option selects 64KB page size with 2 level page tables, which
327	  support a maximum of 42 bits of application virtual memory.
328
329config 64KB_3LEVEL
330	bool "64KB with 3 levels"
331	select PAGE_SIZE_64KB
332	select PGTABLE_3LEVEL
333	help
334	  This option selects 64KB page size with 3 level page tables, which
335	  support a maximum of 55 bits of application virtual memory.
336
337endchoice
338
339config CMDLINE
340	string "Built-in kernel command line"
341	help
342	  For most platforms, the arguments for the kernel's command line
343	  are provided at run-time, during boot. However, there are cases
344	  where either no arguments are being provided or the provided
345	  arguments are insufficient or even invalid.
346
347	  When that occurs, it is possible to define a built-in command
348	  line here and choose how the kernel should use it later on.
349
350choice
351	prompt "Kernel command line type"
352	default CMDLINE_BOOTLOADER
353	help
354	  Choose how the kernel will handle the provided built-in command
355	  line.
356
357config CMDLINE_BOOTLOADER
358	bool "Use bootloader kernel arguments if available"
359	help
360	  Prefer the command-line passed by the boot loader if available.
361	  Use the built-in command line as fallback in case we get nothing
362	  during boot. This is the default behaviour.
363
364config CMDLINE_EXTEND
365	bool "Use built-in to extend bootloader kernel arguments"
366	help
367	  The command-line arguments provided during boot will be
368	  appended to the built-in command line. This is useful in
369	  cases where the provided arguments are insufficient and
370	  you don't want to or cannot modify them.
371
372config CMDLINE_FORCE
373	bool "Always use the built-in kernel command string"
374	help
375	  Always use the built-in command line, even if we get one during
376	  boot. This is useful in case you need to override the provided
377	  command line on systems where you don't have or want control
378	  over it.
379
380endchoice
381
382config BUILTIN_DTB
383	bool "Enable built-in dtb in kernel"
384	depends on OF
385	help
386	  Some existing systems do not provide a canonical device tree to
387	  the kernel at boot time. Let's provide a device tree table in the
388	  kernel, keyed by the dts filename, containing the relevant DTBs.
389
390	  Built-in DTBs are generic enough and can be used as references.
391
392config BUILTIN_DTB_NAME
393	string "Source file for built-in dtb"
394	depends on BUILTIN_DTB
395	help
396	  Base name (without suffix, relative to arch/loongarch/boot/dts/)
397	  for the DTS file that will be used to produce the DTB linked into
398	  the kernel.
399
400config DMI
401	bool "Enable DMI scanning"
402	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
403	default y
404	help
405	  This enables SMBIOS/DMI feature for systems, and scanning of
406	  DMI to identify machine quirks.
407
408config EFI
409	bool "EFI runtime service support"
410	select UCS2_STRING
411	select EFI_RUNTIME_WRAPPERS
412	help
413	  This enables the kernel to use EFI runtime services that are
414	  available (such as the EFI variable services).
415
416config EFI_STUB
417	bool "EFI boot stub support"
418	default y
419	depends on EFI
420	select EFI_GENERIC_STUB
421	help
422	  This kernel feature allows the kernel to be loaded directly by
423	  EFI firmware without the use of a bootloader.
424
425config SCHED_SMT
426	bool "SMT scheduler support"
427	default y
428	help
429	  Improves scheduler's performance when there are multiple
430	  threads in one physical core.
431
432config SMP
433	bool "Multi-Processing support"
434	help
435	  This enables support for systems with more than one CPU. If you have
436	  a system with only one CPU, say N. If you have a system with more
437	  than one CPU, say Y.
438
439	  If you say N here, the kernel will run on uni- and multiprocessor
440	  machines, but will use only one CPU of a multiprocessor machine. If
441	  you say Y here, the kernel will run on many, but not all,
442	  uniprocessor machines. On a uniprocessor machine, the kernel
443	  will run faster if you say N here.
444
445	  See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>.
446
447	  If you don't know what to do here, say N.
448
449config HOTPLUG_CPU
450	bool "Support for hot-pluggable CPUs"
451	depends on SMP
452	select GENERIC_IRQ_MIGRATION
453	help
454	  Say Y here to allow turning CPUs off and on. CPUs can be
455	  controlled through /sys/devices/system/cpu.
456	  (Note: power management support will enable this option
457	    automatically on SMP systems. )
458	  Say N if you want to disable CPU hotplug.
459
460config NR_CPUS
461	int "Maximum number of CPUs (2-256)"
462	range 2 256
463	depends on SMP
464	default "64"
465	help
466	  This allows you to specify the maximum number of CPUs which this
467	  kernel will support.
468
469config NUMA
470	bool "NUMA Support"
471	select SMP
472	select ACPI_NUMA if ACPI
473	help
474	  Say Y to compile the kernel with NUMA (Non-Uniform Memory Access)
475	  support.  This option improves performance on systems with more
476	  than one NUMA node; on single node systems it is generally better
477	  to leave it disabled.
478
479config NODES_SHIFT
480	int
481	default "6"
482	depends on NUMA
483
484config ARCH_FORCE_MAX_ORDER
485	int "Maximum zone order"
486	default "13" if PAGE_SIZE_64KB
487	default "11" if PAGE_SIZE_16KB
488	default "10"
489	help
490	  The kernel memory allocator divides physically contiguous memory
491	  blocks into "zones", where each zone is a power of two number of
492	  pages.  This option selects the largest power of two that the kernel
493	  keeps in the memory allocator.  If you need to allocate very large
494	  blocks of physically contiguous memory, then you may need to
495	  increase this value.
496
497	  The page size is not necessarily 4KB.  Keep this in mind
498	  when choosing a value for this option.
499
500config ARCH_IOREMAP
501	bool "Enable LoongArch DMW-based ioremap()"
502	help
503	  We use generic TLB-based ioremap() by default since it has page
504	  protection support. However, you can enable LoongArch DMW-based
505	  ioremap() for better performance.
506
507config ARCH_WRITECOMBINE
508	bool "Enable WriteCombine (WUC) for ioremap()"
509	help
510	  LoongArch maintains cache coherency in hardware, but when paired
511	  with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which
512	  is similar to WriteCombine) is out of the scope of cache coherency
513	  machanism for PCIe devices (this is a PCIe protocol violation, which
514	  may be fixed in newer chipsets).
515
516	  This means WUC can only used for write-only memory regions now, so
517	  this option is disabled by default, making WUC silently fallback to
518	  SUC for ioremap(). You can enable this option if the kernel is ensured
519	  to run on hardware without this bug.
520
521	  You can override this setting via writecombine=on/off boot parameter.
522
523config ARCH_STRICT_ALIGN
524	bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT
525	default y
526	help
527	  Not all LoongArch cores support h/w unaligned access, we can use
528	  -mstrict-align build parameter to prevent unaligned accesses.
529
530	  CPUs with h/w unaligned access support:
531	  Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
532
533	  CPUs without h/w unaligned access support:
534	  Loongson-2K500/2K1000.
535
536	  This option is enabled by default to make the kernel be able to run
537	  on all LoongArch systems. But you can disable it manually if you want
538	  to run kernel only on systems with h/w unaligned access support in
539	  order to optimise for performance.
540
541config CPU_HAS_FPU
542	bool
543	default y
544
545config CPU_HAS_LSX
546	bool "Support for the Loongson SIMD Extension"
547	depends on AS_HAS_LSX_EXTENSION
548	help
549	  Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers
550	  and a set of SIMD instructions to operate on them. When this option
551	  is enabled the kernel will support allocating & switching LSX
552	  vector register contexts. If you know that your kernel will only be
553	  running on CPUs which do not support LSX or that your userland will
554	  not be making use of it then you may wish to say N here to reduce
555	  the size & complexity of your kernel.
556
557	  If unsure, say Y.
558
559config CPU_HAS_LASX
560	bool "Support for the Loongson Advanced SIMD Extension"
561	depends on CPU_HAS_LSX
562	depends on AS_HAS_LASX_EXTENSION
563	help
564	  Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector
565	  registers and a set of SIMD instructions to operate on them. When this
566	  option is enabled the kernel will support allocating & switching LASX
567	  vector register contexts. If you know that your kernel will only be
568	  running on CPUs which do not support LASX or that your userland will
569	  not be making use of it then you may wish to say N here to reduce
570	  the size & complexity of your kernel.
571
572	  If unsure, say Y.
573
574config CPU_HAS_LBT
575	bool "Support for the Loongson Binary Translation Extension"
576	depends on AS_HAS_LBT_EXTENSION
577	help
578	  Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0
579	  to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop).
580	  Enabling this option allows the kernel to allocate and switch registers
581	  specific to LBT.
582
583	  If you want to use this feature, such as the Loongson Architecture
584	  Translator (LAT), say Y.
585
586config CPU_HAS_PREFETCH
587	bool
588	default y
589
590config ARCH_SUPPORTS_KEXEC
591	def_bool y
592
593config ARCH_SUPPORTS_CRASH_DUMP
594	def_bool y
595
596config ARCH_SELECTS_CRASH_DUMP
597	def_bool y
598	depends on CRASH_DUMP
599	select RELOCATABLE
600
601config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
602	def_bool CRASH_CORE
603
604config RELOCATABLE
605	bool "Relocatable kernel"
606	help
607	  This builds the kernel as a Position Independent Executable (PIE),
608	  which retains all relocation metadata required, so as to relocate
609	  the kernel binary at runtime to a different virtual address from
610	  its link address.
611
612config RANDOMIZE_BASE
613	bool "Randomize the address of the kernel (KASLR)"
614	depends on RELOCATABLE
615	help
616	   Randomizes the physical and virtual address at which the
617	   kernel image is loaded, as a security feature that
618	   deters exploit attempts relying on knowledge of the location
619	   of kernel internals.
620
621	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET.
622
623	   If unsure, say N.
624
625config RANDOMIZE_BASE_MAX_OFFSET
626	hex "Maximum KASLR offset" if EXPERT
627	depends on RANDOMIZE_BASE
628	range 0x0 0x10000000
629	default "0x01000000"
630	help
631	  When KASLR is active, this provides the maximum offset that will
632	  be applied to the kernel image. It should be set according to the
633	  amount of physical RAM available in the target system.
634
635	  This is limited by the size of the lower address memory, 256MB.
636
637endmenu
638
639config ARCH_SELECT_MEMORY_MODEL
640	def_bool y
641
642config ARCH_FLATMEM_ENABLE
643	def_bool y
644	depends on !NUMA
645
646config ARCH_SPARSEMEM_ENABLE
647	def_bool y
648	select SPARSEMEM_VMEMMAP_ENABLE
649	help
650	  Say Y to support efficient handling of sparse physical memory,
651	  for architectures which are either NUMA (Non-Uniform Memory Access)
652	  or have huge holes in the physical address space for other reasons.
653	  See <file:Documentation/mm/numa.rst> for more.
654
655config ARCH_MEMORY_PROBE
656	def_bool y
657	depends on MEMORY_HOTPLUG
658
659config MMU
660	bool
661	default y
662
663config ARCH_MMAP_RND_BITS_MIN
664	default 12
665
666config ARCH_MMAP_RND_BITS_MAX
667	default 18
668
669config ARCH_SUPPORTS_UPROBES
670	def_bool y
671
672config KASAN_SHADOW_OFFSET
673	hex
674	default 0x0
675	depends on KASAN
676
677menu "Power management options"
678
679config ARCH_SUSPEND_POSSIBLE
680	def_bool y
681
682config ARCH_HIBERNATION_POSSIBLE
683	def_bool y
684
685source "kernel/power/Kconfig"
686source "drivers/acpi/Kconfig"
687
688endmenu
689
690source "arch/loongarch/kvm/Kconfig"
691