xref: /linux/arch/loongarch/Kconfig (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
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_PPTT if ACPI
9	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
10	select ARCH_BINFMT_ELF_STATE
11	select ARCH_DISABLE_KASAN_INLINE
12	select ARCH_ENABLE_MEMORY_HOTPLUG
13	select ARCH_ENABLE_MEMORY_HOTREMOVE
14	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
15	select ARCH_HAS_CPU_FINALIZE_INIT
16	select ARCH_HAS_FORTIFY_SOURCE
17	select ARCH_HAS_KCOV
18	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
19	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
20	select ARCH_HAS_PTE_SPECIAL
21	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
22	select ARCH_INLINE_READ_LOCK if !PREEMPTION
23	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
24	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
25	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
26	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
27	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
28	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
29	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
30	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
31	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
32	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
33	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
34	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
35	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
36	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
37	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
38	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
39	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
40	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
41	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
42	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
43	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
44	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
45	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
46	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
47	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
48	select ARCH_KEEP_MEMBLOCK
49	select ARCH_MIGHT_HAVE_PC_PARPORT
50	select ARCH_MIGHT_HAVE_PC_SERIO
51	select ARCH_SPARSEMEM_ENABLE
52	select ARCH_STACKWALK
53	select ARCH_SUPPORTS_ACPI
54	select ARCH_SUPPORTS_ATOMIC_RMW
55	select ARCH_SUPPORTS_HUGETLBFS
56	select ARCH_SUPPORTS_LTO_CLANG
57	select ARCH_SUPPORTS_LTO_CLANG_THIN
58	select ARCH_SUPPORTS_NUMA_BALANCING
59	select ARCH_USE_BUILTIN_BSWAP
60	select ARCH_USE_CMPXCHG_LOCKREF
61	select ARCH_USE_QUEUED_RWLOCKS
62	select ARCH_USE_QUEUED_SPINLOCKS
63	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
64	select ARCH_WANT_LD_ORPHAN_WARN
65	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
66	select ARCH_WANTS_NO_INSTR
67	select BUILDTIME_TABLE_SORT
68	select COMMON_CLK
69	select CPU_PM
70	select EFI
71	select GENERIC_CLOCKEVENTS
72	select GENERIC_CMOS_UPDATE
73	select GENERIC_CPU_AUTOPROBE
74	select GENERIC_ENTRY
75	select GENERIC_GETTIMEOFDAY
76	select GENERIC_IOREMAP if !ARCH_IOREMAP
77	select GENERIC_IRQ_MULTI_HANDLER
78	select GENERIC_IRQ_PROBE
79	select GENERIC_IRQ_SHOW
80	select GENERIC_LIB_ASHLDI3
81	select GENERIC_LIB_ASHRDI3
82	select GENERIC_LIB_CMPDI2
83	select GENERIC_LIB_LSHRDI3
84	select GENERIC_LIB_UCMPDI2
85	select GENERIC_LIB_DEVMEM_IS_ALLOWED
86	select GENERIC_PCI_IOMAP
87	select GENERIC_SCHED_CLOCK
88	select GENERIC_SMP_IDLE_THREAD
89	select GENERIC_TIME_VSYSCALL
90	select GENERIC_VDSO_TIME_NS
91	select GPIOLIB
92	select HAS_IOPORT
93	select HAVE_ARCH_AUDITSYSCALL
94	select HAVE_ARCH_JUMP_LABEL
95	select HAVE_ARCH_JUMP_LABEL_RELATIVE
96	select HAVE_ARCH_KASAN
97	select HAVE_ARCH_KFENCE
98	select HAVE_ARCH_KGDB if PERF_EVENTS
99	select HAVE_ARCH_MMAP_RND_BITS if MMU
100	select HAVE_ARCH_SECCOMP_FILTER
101	select HAVE_ARCH_TRACEHOOK
102	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
103	select HAVE_ASM_MODVERSIONS
104	select HAVE_CONTEXT_TRACKING_USER
105	select HAVE_C_RECORDMCOUNT
106	select HAVE_DEBUG_KMEMLEAK
107	select HAVE_DEBUG_STACKOVERFLOW
108	select HAVE_DMA_CONTIGUOUS
109	select HAVE_DYNAMIC_FTRACE
110	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
111	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
112	select HAVE_DYNAMIC_FTRACE_WITH_REGS
113	select HAVE_EBPF_JIT
114	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
115	select HAVE_EXIT_THREAD
116	select HAVE_FAST_GUP
117	select HAVE_FTRACE_MCOUNT_RECORD
118	select HAVE_FUNCTION_ARG_ACCESS_API
119	select HAVE_FUNCTION_ERROR_INJECTION
120	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
121	select HAVE_FUNCTION_GRAPH_TRACER
122	select HAVE_FUNCTION_TRACER
123	select HAVE_GCC_PLUGINS
124	select HAVE_GENERIC_VDSO
125	select HAVE_HW_BREAKPOINT if PERF_EVENTS
126	select HAVE_IOREMAP_PROT
127	select HAVE_IRQ_EXIT_ON_IRQ_STACK
128	select HAVE_IRQ_TIME_ACCOUNTING
129	select HAVE_KPROBES
130	select HAVE_KPROBES_ON_FTRACE
131	select HAVE_KRETPROBES
132	select HAVE_KVM
133	select HAVE_MOD_ARCH_SPECIFIC
134	select HAVE_NMI
135	select HAVE_PCI
136	select HAVE_PERF_EVENTS
137	select HAVE_PERF_REGS
138	select HAVE_PERF_USER_STACK_DUMP
139	select HAVE_PREEMPT_DYNAMIC_KEY
140	select HAVE_REGS_AND_STACK_ACCESS_API
141	select HAVE_RETHOOK
142	select HAVE_RSEQ
143	select HAVE_RUST
144	select HAVE_SAMPLE_FTRACE_DIRECT
145	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
146	select HAVE_SETUP_PER_CPU_AREA if NUMA
147	select HAVE_STACKPROTECTOR
148	select HAVE_SYSCALL_TRACEPOINTS
149	select HAVE_TIF_NOHZ
150	select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
151	select IRQ_FORCED_THREADING
152	select IRQ_LOONGARCH_CPU
153	select LOCK_MM_AND_FIND_VMA
154	select MMU_GATHER_MERGE_VMAS if MMU
155	select MODULES_USE_ELF_RELA if MODULES
156	select NEED_PER_CPU_EMBED_FIRST_CHUNK
157	select NEED_PER_CPU_PAGE_FIRST_CHUNK
158	select OF
159	select OF_EARLY_FLATTREE
160	select PCI
161	select PCI_DOMAINS_GENERIC
162	select PCI_ECAM if ACPI
163	select PCI_LOONGSON
164	select PCI_MSI_ARCH_FALLBACKS
165	select PCI_QUIRKS
166	select PERF_USE_VMALLOC
167	select RTC_LIB
168	select SMP
169	select SPARSE_IRQ
170	select SYSCTL_ARCH_UNALIGN_ALLOW
171	select SYSCTL_ARCH_UNALIGN_NO_WARN
172	select SYSCTL_EXCEPTION_TRACE
173	select SWIOTLB
174	select TRACE_IRQFLAGS_SUPPORT
175	select USE_PERCPU_NUMA_NODE_ID
176	select USER_STACKTRACE_SUPPORT
177	select ZONE_DMA32
178
179config 32BIT
180	bool
181
182config 64BIT
183	def_bool y
184
185config GENERIC_BUG
186	def_bool y
187	depends on BUG
188
189config GENERIC_BUG_RELATIVE_POINTERS
190	def_bool y
191	depends on GENERIC_BUG
192
193config GENERIC_CALIBRATE_DELAY
194	def_bool y
195
196config GENERIC_CSUM
197	def_bool y
198
199config GENERIC_HWEIGHT
200	def_bool y
201
202config L1_CACHE_SHIFT
203	int
204	default "6"
205
206config LOCKDEP_SUPPORT
207	bool
208	default y
209
210config STACKTRACE_SUPPORT
211	bool
212	default y
213
214# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the
215# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
216# are shared between architectures, and specifically expecting the symbols.
217config MACH_LOONGSON32
218	def_bool 32BIT
219
220config MACH_LOONGSON64
221	def_bool 64BIT
222
223config FIX_EARLYCON_MEM
224	def_bool y
225
226config PAGE_SIZE_4KB
227	bool
228
229config PAGE_SIZE_16KB
230	bool
231
232config PAGE_SIZE_64KB
233	bool
234
235config PGTABLE_2LEVEL
236	bool
237
238config PGTABLE_3LEVEL
239	bool
240
241config PGTABLE_4LEVEL
242	bool
243
244config PGTABLE_LEVELS
245	int
246	default 2 if PGTABLE_2LEVEL
247	default 3 if PGTABLE_3LEVEL
248	default 4 if PGTABLE_4LEVEL
249
250config SCHED_OMIT_FRAME_POINTER
251	bool
252	default y
253
254config AS_HAS_EXPLICIT_RELOCS
255	def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x))
256
257config AS_HAS_FCSR_CLASS
258	def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0)
259
260config AS_HAS_LSX_EXTENSION
261	def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0)
262
263config AS_HAS_LASX_EXTENSION
264	def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0)
265
266config AS_HAS_LBT_EXTENSION
267	def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0)
268
269config AS_HAS_LVZ_EXTENSION
270	def_bool $(as-instr,hvcl 0)
271
272menu "Kernel type and options"
273
274source "kernel/Kconfig.hz"
275
276choice
277	prompt "Page Table Layout"
278	default 16KB_2LEVEL if 32BIT
279	default 16KB_3LEVEL if 64BIT
280	help
281	  Allows choosing the page table layout, which is a combination
282	  of page size and page table levels. The size of virtual memory
283	  address space are determined by the page table layout.
284
285config 4KB_3LEVEL
286	bool "4KB with 3 levels"
287	select PAGE_SIZE_4KB
288	select PGTABLE_3LEVEL
289	help
290	  This option selects 4KB page size with 3 level page tables, which
291	  support a maximum of 39 bits of application virtual memory.
292
293config 4KB_4LEVEL
294	bool "4KB with 4 levels"
295	select PAGE_SIZE_4KB
296	select PGTABLE_4LEVEL
297	help
298	  This option selects 4KB page size with 4 level page tables, which
299	  support a maximum of 48 bits of application virtual memory.
300
301config 16KB_2LEVEL
302	bool "16KB with 2 levels"
303	select PAGE_SIZE_16KB
304	select PGTABLE_2LEVEL
305	help
306	  This option selects 16KB page size with 2 level page tables, which
307	  support a maximum of 36 bits of application virtual memory.
308
309config 16KB_3LEVEL
310	bool "16KB with 3 levels"
311	select PAGE_SIZE_16KB
312	select PGTABLE_3LEVEL
313	help
314	  This option selects 16KB page size with 3 level page tables, which
315	  support a maximum of 47 bits of application virtual memory.
316
317config 64KB_2LEVEL
318	bool "64KB with 2 levels"
319	select PAGE_SIZE_64KB
320	select PGTABLE_2LEVEL
321	help
322	  This option selects 64KB page size with 2 level page tables, which
323	  support a maximum of 42 bits of application virtual memory.
324
325config 64KB_3LEVEL
326	bool "64KB with 3 levels"
327	select PAGE_SIZE_64KB
328	select PGTABLE_3LEVEL
329	help
330	  This option selects 64KB page size with 3 level page tables, which
331	  support a maximum of 55 bits of application virtual memory.
332
333endchoice
334
335config CMDLINE
336	string "Built-in kernel command line"
337	help
338	  For most platforms, the arguments for the kernel's command line
339	  are provided at run-time, during boot. However, there are cases
340	  where either no arguments are being provided or the provided
341	  arguments are insufficient or even invalid.
342
343	  When that occurs, it is possible to define a built-in command
344	  line here and choose how the kernel should use it later on.
345
346choice
347	prompt "Kernel command line type"
348	default CMDLINE_BOOTLOADER
349	help
350	  Choose how the kernel will handle the provided built-in command
351	  line.
352
353config CMDLINE_BOOTLOADER
354	bool "Use bootloader kernel arguments if available"
355	help
356	  Prefer the command-line passed by the boot loader if available.
357	  Use the built-in command line as fallback in case we get nothing
358	  during boot. This is the default behaviour.
359
360config CMDLINE_EXTEND
361	bool "Use built-in to extend bootloader kernel arguments"
362	help
363	  The command-line arguments provided during boot will be
364	  appended to the built-in command line. This is useful in
365	  cases where the provided arguments are insufficient and
366	  you don't want to or cannot modify them.
367
368config CMDLINE_FORCE
369	bool "Always use the built-in kernel command string"
370	help
371	  Always use the built-in command line, even if we get one during
372	  boot. This is useful in case you need to override the provided
373	  command line on systems where you don't have or want control
374	  over it.
375
376endchoice
377
378config DMI
379	bool "Enable DMI scanning"
380	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
381	default y
382	help
383	  This enables SMBIOS/DMI feature for systems, and scanning of
384	  DMI to identify machine quirks.
385
386config EFI
387	bool "EFI runtime service support"
388	select UCS2_STRING
389	select EFI_RUNTIME_WRAPPERS
390	help
391	  This enables the kernel to use EFI runtime services that are
392	  available (such as the EFI variable services).
393
394config EFI_STUB
395	bool "EFI boot stub support"
396	default y
397	depends on EFI
398	select EFI_GENERIC_STUB
399	help
400	  This kernel feature allows the kernel to be loaded directly by
401	  EFI firmware without the use of a bootloader.
402
403config SCHED_SMT
404	bool "SMT scheduler support"
405	default y
406	help
407	  Improves scheduler's performance when there are multiple
408	  threads in one physical core.
409
410config SMP
411	bool "Multi-Processing support"
412	help
413	  This enables support for systems with more than one CPU. If you have
414	  a system with only one CPU, say N. If you have a system with more
415	  than one CPU, say Y.
416
417	  If you say N here, the kernel will run on uni- and multiprocessor
418	  machines, but will use only one CPU of a multiprocessor machine. If
419	  you say Y here, the kernel will run on many, but not all,
420	  uniprocessor machines. On a uniprocessor machine, the kernel
421	  will run faster if you say N here.
422
423	  See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>.
424
425	  If you don't know what to do here, say N.
426
427config HOTPLUG_CPU
428	bool "Support for hot-pluggable CPUs"
429	depends on SMP
430	select GENERIC_IRQ_MIGRATION
431	help
432	  Say Y here to allow turning CPUs off and on. CPUs can be
433	  controlled through /sys/devices/system/cpu.
434	  (Note: power management support will enable this option
435	    automatically on SMP systems. )
436	  Say N if you want to disable CPU hotplug.
437
438config NR_CPUS
439	int "Maximum number of CPUs (2-256)"
440	range 2 256
441	depends on SMP
442	default "64"
443	help
444	  This allows you to specify the maximum number of CPUs which this
445	  kernel will support.
446
447config NUMA
448	bool "NUMA Support"
449	select SMP
450	select ACPI_NUMA if ACPI
451	help
452	  Say Y to compile the kernel with NUMA (Non-Uniform Memory Access)
453	  support.  This option improves performance on systems with more
454	  than one NUMA node; on single node systems it is generally better
455	  to leave it disabled.
456
457config NODES_SHIFT
458	int
459	default "6"
460	depends on NUMA
461
462config ARCH_FORCE_MAX_ORDER
463	int "Maximum zone order"
464	default "13" if PAGE_SIZE_64KB
465	default "11" if PAGE_SIZE_16KB
466	default "10"
467	help
468	  The kernel memory allocator divides physically contiguous memory
469	  blocks into "zones", where each zone is a power of two number of
470	  pages.  This option selects the largest power of two that the kernel
471	  keeps in the memory allocator.  If you need to allocate very large
472	  blocks of physically contiguous memory, then you may need to
473	  increase this value.
474
475	  The page size is not necessarily 4KB.  Keep this in mind
476	  when choosing a value for this option.
477
478config ARCH_IOREMAP
479	bool "Enable LoongArch DMW-based ioremap()"
480	help
481	  We use generic TLB-based ioremap() by default since it has page
482	  protection support. However, you can enable LoongArch DMW-based
483	  ioremap() for better performance.
484
485config ARCH_WRITECOMBINE
486	bool "Enable WriteCombine (WUC) for ioremap()"
487	help
488	  LoongArch maintains cache coherency in hardware, but when paired
489	  with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which
490	  is similar to WriteCombine) is out of the scope of cache coherency
491	  machanism for PCIe devices (this is a PCIe protocol violation, which
492	  may be fixed in newer chipsets).
493
494	  This means WUC can only used for write-only memory regions now, so
495	  this option is disabled by default, making WUC silently fallback to
496	  SUC for ioremap(). You can enable this option if the kernel is ensured
497	  to run on hardware without this bug.
498
499	  You can override this setting via writecombine=on/off boot parameter.
500
501config ARCH_STRICT_ALIGN
502	bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT
503	default y
504	help
505	  Not all LoongArch cores support h/w unaligned access, we can use
506	  -mstrict-align build parameter to prevent unaligned accesses.
507
508	  CPUs with h/w unaligned access support:
509	  Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
510
511	  CPUs without h/w unaligned access support:
512	  Loongson-2K500/2K1000.
513
514	  This option is enabled by default to make the kernel be able to run
515	  on all LoongArch systems. But you can disable it manually if you want
516	  to run kernel only on systems with h/w unaligned access support in
517	  order to optimise for performance.
518
519config CPU_HAS_FPU
520	bool
521	default y
522
523config CPU_HAS_LSX
524	bool "Support for the Loongson SIMD Extension"
525	depends on AS_HAS_LSX_EXTENSION
526	help
527	  Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers
528	  and a set of SIMD instructions to operate on them. When this option
529	  is enabled the kernel will support allocating & switching LSX
530	  vector register contexts. If you know that your kernel will only be
531	  running on CPUs which do not support LSX or that your userland will
532	  not be making use of it then you may wish to say N here to reduce
533	  the size & complexity of your kernel.
534
535	  If unsure, say Y.
536
537config CPU_HAS_LASX
538	bool "Support for the Loongson Advanced SIMD Extension"
539	depends on CPU_HAS_LSX
540	depends on AS_HAS_LASX_EXTENSION
541	help
542	  Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector
543	  registers and a set of SIMD instructions to operate on them. When this
544	  option is enabled the kernel will support allocating & switching LASX
545	  vector register contexts. If you know that your kernel will only be
546	  running on CPUs which do not support LASX or that your userland will
547	  not be making use of it then you may wish to say N here to reduce
548	  the size & complexity of your kernel.
549
550	  If unsure, say Y.
551
552config CPU_HAS_LBT
553	bool "Support for the Loongson Binary Translation Extension"
554	depends on AS_HAS_LBT_EXTENSION
555	help
556	  Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0
557	  to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop).
558	  Enabling this option allows the kernel to allocate and switch registers
559	  specific to LBT.
560
561	  If you want to use this feature, such as the Loongson Architecture
562	  Translator (LAT), say Y.
563
564config CPU_HAS_PREFETCH
565	bool
566	default y
567
568config ARCH_SUPPORTS_KEXEC
569	def_bool y
570
571config ARCH_SUPPORTS_CRASH_DUMP
572	def_bool y
573
574config ARCH_SELECTS_CRASH_DUMP
575	def_bool y
576	depends on CRASH_DUMP
577	select RELOCATABLE
578
579config RELOCATABLE
580	bool "Relocatable kernel"
581	help
582	  This builds the kernel as a Position Independent Executable (PIE),
583	  which retains all relocation metadata required, so as to relocate
584	  the kernel binary at runtime to a different virtual address from
585	  its link address.
586
587config RANDOMIZE_BASE
588	bool "Randomize the address of the kernel (KASLR)"
589	depends on RELOCATABLE
590	help
591	   Randomizes the physical and virtual address at which the
592	   kernel image is loaded, as a security feature that
593	   deters exploit attempts relying on knowledge of the location
594	   of kernel internals.
595
596	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET.
597
598	   If unsure, say N.
599
600config RANDOMIZE_BASE_MAX_OFFSET
601	hex "Maximum KASLR offset" if EXPERT
602	depends on RANDOMIZE_BASE
603	range 0x0 0x10000000
604	default "0x01000000"
605	help
606	  When KASLR is active, this provides the maximum offset that will
607	  be applied to the kernel image. It should be set according to the
608	  amount of physical RAM available in the target system.
609
610	  This is limited by the size of the lower address memory, 256MB.
611
612config SECCOMP
613	bool "Enable seccomp to safely compute untrusted bytecode"
614	depends on PROC_FS
615	default y
616	help
617	  This kernel feature is useful for number crunching applications
618	  that may need to compute untrusted bytecode during their
619	  execution. By using pipes or other transports made available to
620	  the process as file descriptors supporting the read/write
621	  syscalls, it's possible to isolate those applications in
622	  their own address space using seccomp. Once seccomp is
623	  enabled via /proc/<pid>/seccomp, it cannot be disabled
624	  and the task is only allowed to execute a few safe syscalls
625	  defined by each seccomp mode.
626
627	  If unsure, say Y. Only embedded should say N here.
628
629endmenu
630
631config ARCH_SELECT_MEMORY_MODEL
632	def_bool y
633
634config ARCH_FLATMEM_ENABLE
635	def_bool y
636	depends on !NUMA
637
638config ARCH_SPARSEMEM_ENABLE
639	def_bool y
640	select SPARSEMEM_VMEMMAP_ENABLE
641	help
642	  Say Y to support efficient handling of sparse physical memory,
643	  for architectures which are either NUMA (Non-Uniform Memory Access)
644	  or have huge holes in the physical address space for other reasons.
645	  See <file:Documentation/mm/numa.rst> for more.
646
647config ARCH_ENABLE_THP_MIGRATION
648	def_bool y
649	depends on TRANSPARENT_HUGEPAGE
650
651config ARCH_MEMORY_PROBE
652	def_bool y
653	depends on MEMORY_HOTPLUG
654
655config MMU
656	bool
657	default y
658
659config ARCH_MMAP_RND_BITS_MIN
660	default 12
661
662config ARCH_MMAP_RND_BITS_MAX
663	default 18
664
665config ARCH_SUPPORTS_UPROBES
666	def_bool y
667
668config KASAN_SHADOW_OFFSET
669	hex
670	default 0x0
671	depends on KASAN
672
673menu "Power management options"
674
675config ARCH_SUSPEND_POSSIBLE
676	def_bool y
677
678config ARCH_HIBERNATION_POSSIBLE
679	def_bool y
680
681source "kernel/power/Kconfig"
682source "drivers/acpi/Kconfig"
683
684endmenu
685
686source "arch/loongarch/kvm/Kconfig"
687