xref: /openbmc/linux/arch/loongarch/Kconfig (revision 3dfbe6a73ae80429ccd268749e91c0d8d1526107)
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_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
15	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
16	select ARCH_HAS_CPU_FINALIZE_INIT
17	select ARCH_HAS_FORTIFY_SOURCE
18	select ARCH_HAS_KCOV
19	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
20	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
21	select ARCH_HAS_PTE_SPECIAL
22	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
23	select ARCH_INLINE_READ_LOCK if !PREEMPTION
24	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
25	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
26	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
27	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
28	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
29	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
30	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
31	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
32	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
33	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
34	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
35	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
36	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
37	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
38	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
39	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
40	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
41	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
42	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
43	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
44	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
45	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
46	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
47	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
48	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
49	select ARCH_KEEP_MEMBLOCK
50	select ARCH_MIGHT_HAVE_PC_PARPORT
51	select ARCH_MIGHT_HAVE_PC_SERIO
52	select ARCH_SPARSEMEM_ENABLE
53	select ARCH_STACKWALK
54	select ARCH_SUPPORTS_ACPI
55	select ARCH_SUPPORTS_ATOMIC_RMW
56	select ARCH_SUPPORTS_HUGETLBFS
57	select ARCH_SUPPORTS_LTO_CLANG
58	select ARCH_SUPPORTS_LTO_CLANG_THIN
59	select ARCH_SUPPORTS_NUMA_BALANCING
60	select ARCH_USE_BUILTIN_BSWAP
61	select ARCH_USE_CMPXCHG_LOCKREF
62	select ARCH_USE_MEMTEST
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_ENTRY
77	select GENERIC_GETTIMEOFDAY
78	select GENERIC_IOREMAP if !ARCH_IOREMAP
79	select GENERIC_IRQ_MULTI_HANDLER
80	select GENERIC_IRQ_PROBE
81	select GENERIC_IRQ_SHOW
82	select GENERIC_LIB_ASHLDI3
83	select GENERIC_LIB_ASHRDI3
84	select GENERIC_LIB_CMPDI2
85	select GENERIC_LIB_LSHRDI3
86	select GENERIC_LIB_UCMPDI2
87	select GENERIC_LIB_DEVMEM_IS_ALLOWED
88	select GENERIC_PCI_IOMAP
89	select GENERIC_SCHED_CLOCK
90	select GENERIC_SMP_IDLE_THREAD
91	select GENERIC_TIME_VSYSCALL
92	select GENERIC_VDSO_TIME_NS
93	select GPIOLIB
94	select HAS_IOPORT
95	select HAVE_ARCH_AUDITSYSCALL
96	select HAVE_ARCH_JUMP_LABEL
97	select HAVE_ARCH_JUMP_LABEL_RELATIVE
98	select HAVE_ARCH_KASAN
99	select HAVE_ARCH_KFENCE
100	select HAVE_ARCH_KGDB if PERF_EVENTS
101	select HAVE_ARCH_MMAP_RND_BITS if MMU
102	select HAVE_ARCH_SECCOMP
103	select HAVE_ARCH_SECCOMP_FILTER
104	select HAVE_ARCH_TRACEHOOK
105	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
106	select HAVE_ASM_MODVERSIONS
107	select HAVE_CONTEXT_TRACKING_USER
108	select HAVE_C_RECORDMCOUNT
109	select HAVE_DEBUG_KMEMLEAK
110	select HAVE_DEBUG_STACKOVERFLOW
111	select HAVE_DMA_CONTIGUOUS
112	select HAVE_DYNAMIC_FTRACE
113	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
114	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
115	select HAVE_DYNAMIC_FTRACE_WITH_REGS
116	select HAVE_EBPF_JIT
117	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
118	select HAVE_EXIT_THREAD
119	select HAVE_FAST_GUP
120	select HAVE_FTRACE_MCOUNT_RECORD
121	select HAVE_FUNCTION_ARG_ACCESS_API
122	select HAVE_FUNCTION_ERROR_INJECTION
123	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
124	select HAVE_FUNCTION_GRAPH_TRACER
125	select HAVE_FUNCTION_TRACER
126	select HAVE_GCC_PLUGINS
127	select HAVE_GENERIC_VDSO
128	select HAVE_HW_BREAKPOINT if PERF_EVENTS
129	select HAVE_IOREMAP_PROT
130	select HAVE_IRQ_EXIT_ON_IRQ_STACK
131	select HAVE_IRQ_TIME_ACCOUNTING
132	select HAVE_KPROBES
133	select HAVE_KPROBES_ON_FTRACE
134	select HAVE_KRETPROBES
135	select HAVE_MOD_ARCH_SPECIFIC
136	select HAVE_NMI
137	select HAVE_PCI
138	select HAVE_PERF_EVENTS
139	select HAVE_PERF_REGS
140	select HAVE_PERF_USER_STACK_DUMP
141	select HAVE_REGS_AND_STACK_ACCESS_API
142	select HAVE_RETHOOK
143	select HAVE_RSEQ
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
269menu "Kernel type and options"
270
271source "kernel/Kconfig.hz"
272
273choice
274	prompt "Page Table Layout"
275	default 16KB_2LEVEL if 32BIT
276	default 16KB_3LEVEL if 64BIT
277	help
278	  Allows choosing the page table layout, which is a combination
279	  of page size and page table levels. The size of virtual memory
280	  address space are determined by the page table layout.
281
282config 4KB_3LEVEL
283	bool "4KB with 3 levels"
284	select PAGE_SIZE_4KB
285	select PGTABLE_3LEVEL
286	help
287	  This option selects 4KB page size with 3 level page tables, which
288	  support a maximum of 39 bits of application virtual memory.
289
290config 4KB_4LEVEL
291	bool "4KB with 4 levels"
292	select PAGE_SIZE_4KB
293	select PGTABLE_4LEVEL
294	help
295	  This option selects 4KB page size with 4 level page tables, which
296	  support a maximum of 48 bits of application virtual memory.
297
298config 16KB_2LEVEL
299	bool "16KB with 2 levels"
300	select PAGE_SIZE_16KB
301	select PGTABLE_2LEVEL
302	help
303	  This option selects 16KB page size with 2 level page tables, which
304	  support a maximum of 36 bits of application virtual memory.
305
306config 16KB_3LEVEL
307	bool "16KB with 3 levels"
308	select PAGE_SIZE_16KB
309	select PGTABLE_3LEVEL
310	help
311	  This option selects 16KB page size with 3 level page tables, which
312	  support a maximum of 47 bits of application virtual memory.
313
314config 64KB_2LEVEL
315	bool "64KB with 2 levels"
316	select PAGE_SIZE_64KB
317	select PGTABLE_2LEVEL
318	help
319	  This option selects 64KB page size with 2 level page tables, which
320	  support a maximum of 42 bits of application virtual memory.
321
322config 64KB_3LEVEL
323	bool "64KB with 3 levels"
324	select PAGE_SIZE_64KB
325	select PGTABLE_3LEVEL
326	help
327	  This option selects 64KB page size with 3 level page tables, which
328	  support a maximum of 55 bits of application virtual memory.
329
330endchoice
331
332config CMDLINE
333	string "Built-in kernel command line"
334	help
335	  For most platforms, the arguments for the kernel's command line
336	  are provided at run-time, during boot. However, there are cases
337	  where either no arguments are being provided or the provided
338	  arguments are insufficient or even invalid.
339
340	  When that occurs, it is possible to define a built-in command
341	  line here and choose how the kernel should use it later on.
342
343choice
344	prompt "Kernel command line type"
345	default CMDLINE_BOOTLOADER
346	help
347	  Choose how the kernel will handle the provided built-in command
348	  line.
349
350config CMDLINE_BOOTLOADER
351	bool "Use bootloader kernel arguments if available"
352	help
353	  Prefer the command-line passed by the boot loader if available.
354	  Use the built-in command line as fallback in case we get nothing
355	  during boot. This is the default behaviour.
356
357config CMDLINE_EXTEND
358	bool "Use built-in to extend bootloader kernel arguments"
359	help
360	  The built-in command line will be appended to the command-
361	  line arguments provided during boot. This is useful in
362	  cases where the provided arguments are insufficient and
363	  you don't want to or cannot modify them.
364
365config CMDLINE_FORCE
366	bool "Always use the built-in kernel command string"
367	help
368	  Always use the built-in command line, even if we get one during
369	  boot. This is useful in case you need to override the provided
370	  command line on systems where you don't have or want control
371	  over it.
372
373endchoice
374
375config DMI
376	bool "Enable DMI scanning"
377	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
378	default y
379	help
380	  This enables SMBIOS/DMI feature for systems, and scanning of
381	  DMI to identify machine quirks.
382
383config EFI
384	bool "EFI runtime service support"
385	select UCS2_STRING
386	select EFI_RUNTIME_WRAPPERS
387	help
388	  This enables the kernel to use EFI runtime services that are
389	  available (such as the EFI variable services).
390
391config EFI_STUB
392	bool "EFI boot stub support"
393	default y
394	depends on EFI
395	select EFI_GENERIC_STUB
396	help
397	  This kernel feature allows the kernel to be loaded directly by
398	  EFI firmware without the use of a bootloader.
399
400config SCHED_SMT
401	bool "SMT scheduler support"
402	default y
403	help
404	  Improves scheduler's performance when there are multiple
405	  threads in one physical core.
406
407config SMP
408	bool "Multi-Processing support"
409	help
410	  This enables support for systems with more than one CPU. If you have
411	  a system with only one CPU, say N. If you have a system with more
412	  than one CPU, say Y.
413
414	  If you say N here, the kernel will run on uni- and multiprocessor
415	  machines, but will use only one CPU of a multiprocessor machine. If
416	  you say Y here, the kernel will run on many, but not all,
417	  uniprocessor machines. On a uniprocessor machine, the kernel
418	  will run faster if you say N here.
419
420	  See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>.
421
422	  If you don't know what to do here, say N.
423
424config HOTPLUG_CPU
425	bool "Support for hot-pluggable CPUs"
426	depends on SMP
427	select GENERIC_IRQ_MIGRATION
428	help
429	  Say Y here to allow turning CPUs off and on. CPUs can be
430	  controlled through /sys/devices/system/cpu.
431	  (Note: power management support will enable this option
432	    automatically on SMP systems. )
433	  Say N if you want to disable CPU hotplug.
434
435config NR_CPUS
436	int "Maximum number of CPUs (2-256)"
437	range 2 256
438	depends on SMP
439	default "64"
440	help
441	  This allows you to specify the maximum number of CPUs which this
442	  kernel will support.
443
444config NUMA
445	bool "NUMA Support"
446	select SMP
447	select ACPI_NUMA if ACPI
448	help
449	  Say Y to compile the kernel with NUMA (Non-Uniform Memory Access)
450	  support.  This option improves performance on systems with more
451	  than one NUMA node; on single node systems it is generally better
452	  to leave it disabled.
453
454config NODES_SHIFT
455	int
456	default "6"
457	depends on NUMA
458
459config ARCH_FORCE_MAX_ORDER
460	int "Maximum zone order"
461	default "13" if PAGE_SIZE_64KB
462	default "11" if PAGE_SIZE_16KB
463	default "10"
464	help
465	  The kernel memory allocator divides physically contiguous memory
466	  blocks into "zones", where each zone is a power of two number of
467	  pages.  This option selects the largest power of two that the kernel
468	  keeps in the memory allocator.  If you need to allocate very large
469	  blocks of physically contiguous memory, then you may need to
470	  increase this value.
471
472	  The page size is not necessarily 4KB.  Keep this in mind
473	  when choosing a value for this option.
474
475config ARCH_IOREMAP
476	bool "Enable LoongArch DMW-based ioremap()"
477	help
478	  We use generic TLB-based ioremap() by default since it has page
479	  protection support. However, you can enable LoongArch DMW-based
480	  ioremap() for better performance.
481
482config ARCH_WRITECOMBINE
483	bool "Enable WriteCombine (WUC) for ioremap()"
484	help
485	  LoongArch maintains cache coherency in hardware, but when paired
486	  with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which
487	  is similar to WriteCombine) is out of the scope of cache coherency
488	  machanism for PCIe devices (this is a PCIe protocol violation, which
489	  may be fixed in newer chipsets).
490
491	  This means WUC can only used for write-only memory regions now, so
492	  this option is disabled by default, making WUC silently fallback to
493	  SUC for ioremap(). You can enable this option if the kernel is ensured
494	  to run on hardware without this bug.
495
496	  You can override this setting via writecombine=on/off boot parameter.
497
498config ARCH_STRICT_ALIGN
499	bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT
500	default y
501	help
502	  Not all LoongArch cores support h/w unaligned access, we can use
503	  -mstrict-align build parameter to prevent unaligned accesses.
504
505	  CPUs with h/w unaligned access support:
506	  Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
507
508	  CPUs without h/w unaligned access support:
509	  Loongson-2K500/2K1000.
510
511	  This option is enabled by default to make the kernel be able to run
512	  on all LoongArch systems. But you can disable it manually if you want
513	  to run kernel only on systems with h/w unaligned access support in
514	  order to optimise for performance.
515
516config CPU_HAS_FPU
517	bool
518	default y
519
520config CPU_HAS_LSX
521	bool "Support for the Loongson SIMD Extension"
522	depends on AS_HAS_LSX_EXTENSION
523	help
524	  Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers
525	  and a set of SIMD instructions to operate on them. When this option
526	  is enabled the kernel will support allocating & switching LSX
527	  vector register contexts. If you know that your kernel will only be
528	  running on CPUs which do not support LSX or that your userland will
529	  not be making use of it then you may wish to say N here to reduce
530	  the size & complexity of your kernel.
531
532	  If unsure, say Y.
533
534config CPU_HAS_LASX
535	bool "Support for the Loongson Advanced SIMD Extension"
536	depends on CPU_HAS_LSX
537	depends on AS_HAS_LASX_EXTENSION
538	help
539	  Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector
540	  registers and a set of SIMD instructions to operate on them. When this
541	  option is enabled the kernel will support allocating & switching LASX
542	  vector register contexts. If you know that your kernel will only be
543	  running on CPUs which do not support LASX or that your userland will
544	  not be making use of it then you may wish to say N here to reduce
545	  the size & complexity of your kernel.
546
547	  If unsure, say Y.
548
549config CPU_HAS_LBT
550	bool "Support for the Loongson Binary Translation Extension"
551	depends on AS_HAS_LBT_EXTENSION
552	help
553	  Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0
554	  to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop).
555	  Enabling this option allows the kernel to allocate and switch registers
556	  specific to LBT.
557
558	  If you want to use this feature, such as the Loongson Architecture
559	  Translator (LAT), say Y.
560
561config CPU_HAS_PREFETCH
562	bool
563	default y
564
565config ARCH_SUPPORTS_KEXEC
566	def_bool y
567
568config ARCH_SUPPORTS_CRASH_DUMP
569	def_bool y
570
571config ARCH_SELECTS_CRASH_DUMP
572	def_bool y
573	depends on CRASH_DUMP
574	select RELOCATABLE
575
576config RELOCATABLE
577	bool "Relocatable kernel"
578	help
579	  This builds the kernel as a Position Independent Executable (PIE),
580	  which retains all relocation metadata required, so as to relocate
581	  the kernel binary at runtime to a different virtual address from
582	  its link address.
583
584config RANDOMIZE_BASE
585	bool "Randomize the address of the kernel (KASLR)"
586	depends on RELOCATABLE
587	help
588	   Randomizes the physical and virtual address at which the
589	   kernel image is loaded, as a security feature that
590	   deters exploit attempts relying on knowledge of the location
591	   of kernel internals.
592
593	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET.
594
595	   If unsure, say N.
596
597config RANDOMIZE_BASE_MAX_OFFSET
598	hex "Maximum KASLR offset" if EXPERT
599	depends on RANDOMIZE_BASE
600	range 0x0 0x10000000
601	default "0x01000000"
602	help
603	  When KASLR is active, this provides the maximum offset that will
604	  be applied to the kernel image. It should be set according to the
605	  amount of physical RAM available in the target system.
606
607	  This is limited by the size of the lower address memory, 256MB.
608
609endmenu
610
611config ARCH_SELECT_MEMORY_MODEL
612	def_bool y
613
614config ARCH_FLATMEM_ENABLE
615	def_bool y
616	depends on !NUMA
617
618config ARCH_SPARSEMEM_ENABLE
619	def_bool y
620	select SPARSEMEM_VMEMMAP_ENABLE
621	help
622	  Say Y to support efficient handling of sparse physical memory,
623	  for architectures which are either NUMA (Non-Uniform Memory Access)
624	  or have huge holes in the physical address space for other reasons.
625	  See <file:Documentation/mm/numa.rst> for more.
626
627config ARCH_MEMORY_PROBE
628	def_bool y
629	depends on MEMORY_HOTPLUG
630
631config MMU
632	bool
633	default y
634
635config ARCH_MMAP_RND_BITS_MIN
636	default 12
637
638config ARCH_MMAP_RND_BITS_MAX
639	default 18
640
641config ARCH_SUPPORTS_UPROBES
642	def_bool y
643
644config KASAN_SHADOW_OFFSET
645	hex
646	default 0x0
647	depends on KASAN
648
649menu "Power management options"
650
651config ARCH_SUSPEND_POSSIBLE
652	def_bool y
653
654config ARCH_HIBERNATION_POSSIBLE
655	def_bool y
656
657source "kernel/power/Kconfig"
658source "drivers/acpi/Kconfig"
659
660endmenu
661