xref: /linux/arch/loongarch/Kconfig (revision 8f8d74ee110c02137f5b78ca0a2bd6c10331f267)
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_CURRENT_STACK_POINTER
19	select ARCH_HAS_FAST_MULTIPLIER
20	select ARCH_HAS_FORTIFY_SOURCE
21	select ARCH_HAS_KCOV
22	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
23	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
24	select ARCH_HAS_PTE_SPECIAL
25	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
26	select ARCH_INLINE_READ_LOCK if !PREEMPTION
27	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
28	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
29	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
30	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
31	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
32	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
33	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
34	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
35	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
36	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
37	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
38	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
39	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
40	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
41	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
42	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
43	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
44	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
45	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
46	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
47	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
48	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
49	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
50	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
51	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
52	select ARCH_KEEP_MEMBLOCK
53	select ARCH_MIGHT_HAVE_PC_PARPORT
54	select ARCH_MIGHT_HAVE_PC_SERIO
55	select ARCH_SPARSEMEM_ENABLE
56	select ARCH_STACKWALK
57	select ARCH_SUPPORTS_ACPI
58	select ARCH_SUPPORTS_ATOMIC_RMW
59	select ARCH_SUPPORTS_HUGETLBFS
60	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
61	select ARCH_SUPPORTS_LTO_CLANG
62	select ARCH_SUPPORTS_LTO_CLANG_THIN
63	select ARCH_SUPPORTS_NUMA_BALANCING
64	select ARCH_USE_BUILTIN_BSWAP
65	select ARCH_USE_CMPXCHG_LOCKREF
66	select ARCH_USE_QUEUED_RWLOCKS
67	select ARCH_USE_QUEUED_SPINLOCKS
68	select ARCH_WANT_DEFAULT_BPF_JIT
69	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
70	select ARCH_WANT_LD_ORPHAN_WARN
71	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
72	select ARCH_WANTS_NO_INSTR
73	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
74	select BUILDTIME_TABLE_SORT
75	select COMMON_CLK
76	select CPU_PM
77	select EFI
78	select GENERIC_CLOCKEVENTS
79	select GENERIC_CMOS_UPDATE
80	select GENERIC_CPU_AUTOPROBE
81	select GENERIC_CPU_DEVICES
82	select GENERIC_ENTRY
83	select GENERIC_GETTIMEOFDAY
84	select GENERIC_IOREMAP if !ARCH_IOREMAP
85	select GENERIC_IRQ_MULTI_HANDLER
86	select GENERIC_IRQ_PROBE
87	select GENERIC_IRQ_SHOW
88	select GENERIC_LIB_ASHLDI3
89	select GENERIC_LIB_ASHRDI3
90	select GENERIC_LIB_CMPDI2
91	select GENERIC_LIB_LSHRDI3
92	select GENERIC_LIB_UCMPDI2
93	select GENERIC_LIB_DEVMEM_IS_ALLOWED
94	select GENERIC_PCI_IOMAP
95	select GENERIC_SCHED_CLOCK
96	select GENERIC_SMP_IDLE_THREAD
97	select GENERIC_TIME_VSYSCALL
98	select GENERIC_VDSO_TIME_NS
99	select GPIOLIB
100	select HAS_IOPORT
101	select HAVE_ARCH_AUDITSYSCALL
102	select HAVE_ARCH_JUMP_LABEL
103	select HAVE_ARCH_JUMP_LABEL_RELATIVE
104	select HAVE_ARCH_KASAN
105	select HAVE_ARCH_KFENCE
106	select HAVE_ARCH_KGDB if PERF_EVENTS
107	select HAVE_ARCH_MMAP_RND_BITS if MMU
108	select HAVE_ARCH_SECCOMP
109	select HAVE_ARCH_SECCOMP_FILTER
110	select HAVE_ARCH_TRACEHOOK
111	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
112	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
113	select HAVE_ASM_MODVERSIONS
114	select HAVE_CONTEXT_TRACKING_USER
115	select HAVE_C_RECORDMCOUNT
116	select HAVE_DEBUG_KMEMLEAK
117	select HAVE_DEBUG_STACKOVERFLOW
118	select HAVE_DMA_CONTIGUOUS
119	select HAVE_DYNAMIC_FTRACE
120	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
121	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
122	select HAVE_DYNAMIC_FTRACE_WITH_REGS
123	select HAVE_EBPF_JIT
124	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
125	select HAVE_EXIT_THREAD
126	select HAVE_FAST_GUP
127	select HAVE_FTRACE_MCOUNT_RECORD
128	select HAVE_FUNCTION_ARG_ACCESS_API
129	select HAVE_FUNCTION_ERROR_INJECTION
130	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
131	select HAVE_FUNCTION_GRAPH_TRACER
132	select HAVE_FUNCTION_TRACER
133	select HAVE_GCC_PLUGINS
134	select HAVE_GENERIC_VDSO
135	select HAVE_HW_BREAKPOINT if PERF_EVENTS
136	select HAVE_IOREMAP_PROT
137	select HAVE_IRQ_EXIT_ON_IRQ_STACK
138	select HAVE_IRQ_TIME_ACCOUNTING
139	select HAVE_KPROBES
140	select HAVE_KPROBES_ON_FTRACE
141	select HAVE_KRETPROBES
142	select HAVE_LIVEPATCH
143	select HAVE_MOD_ARCH_SPECIFIC
144	select HAVE_NMI
145	select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS
146	select HAVE_PCI
147	select HAVE_PERF_EVENTS
148	select HAVE_PERF_REGS
149	select HAVE_PERF_USER_STACK_DUMP
150	select HAVE_PREEMPT_DYNAMIC_KEY
151	select HAVE_REGS_AND_STACK_ACCESS_API
152	select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC
153	select HAVE_RETHOOK
154	select HAVE_RSEQ
155	select HAVE_RUST
156	select HAVE_SAMPLE_FTRACE_DIRECT
157	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
158	select HAVE_SETUP_PER_CPU_AREA if NUMA
159	select HAVE_STACK_VALIDATION if HAVE_OBJTOOL
160	select HAVE_STACKPROTECTOR
161	select HAVE_SYSCALL_TRACEPOINTS
162	select HAVE_TIF_NOHZ
163	select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
164	select IRQ_FORCED_THREADING
165	select IRQ_LOONGARCH_CPU
166	select LOCK_MM_AND_FIND_VMA
167	select MMU_GATHER_MERGE_VMAS if MMU
168	select MODULES_USE_ELF_RELA if MODULES
169	select NEED_PER_CPU_EMBED_FIRST_CHUNK
170	select NEED_PER_CPU_PAGE_FIRST_CHUNK
171	select OF
172	select OF_EARLY_FLATTREE
173	select PCI
174	select PCI_DOMAINS_GENERIC
175	select PCI_ECAM if ACPI
176	select PCI_LOONGSON
177	select PCI_MSI_ARCH_FALLBACKS
178	select PCI_QUIRKS
179	select PERF_USE_VMALLOC
180	select RTC_LIB
181	select SPARSE_IRQ
182	select SYSCTL_ARCH_UNALIGN_ALLOW
183	select SYSCTL_ARCH_UNALIGN_NO_WARN
184	select SYSCTL_EXCEPTION_TRACE
185	select SWIOTLB
186	select TRACE_IRQFLAGS_SUPPORT
187	select USE_PERCPU_NUMA_NODE_ID
188	select USER_STACKTRACE_SUPPORT
189	select ZONE_DMA32
190
191config 32BIT
192	bool
193
194config 64BIT
195	def_bool y
196
197config GENERIC_BUG
198	def_bool y
199	depends on BUG
200
201config GENERIC_BUG_RELATIVE_POINTERS
202	def_bool y
203	depends on GENERIC_BUG
204
205config GENERIC_CALIBRATE_DELAY
206	def_bool y
207
208config GENERIC_CSUM
209	def_bool y
210
211config GENERIC_HWEIGHT
212	def_bool y
213
214config L1_CACHE_SHIFT
215	int
216	default "6"
217
218config LOCKDEP_SUPPORT
219	bool
220	default y
221
222config STACKTRACE_SUPPORT
223	bool
224	default y
225
226# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the
227# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
228# are shared between architectures, and specifically expecting the symbols.
229config MACH_LOONGSON32
230	def_bool 32BIT
231
232config MACH_LOONGSON64
233	def_bool 64BIT
234
235config FIX_EARLYCON_MEM
236	def_bool y
237
238config PGTABLE_2LEVEL
239	bool
240
241config PGTABLE_3LEVEL
242	bool
243
244config PGTABLE_4LEVEL
245	bool
246
247config PGTABLE_LEVELS
248	int
249	default 2 if PGTABLE_2LEVEL
250	default 3 if PGTABLE_3LEVEL
251	default 4 if PGTABLE_4LEVEL
252
253config SCHED_OMIT_FRAME_POINTER
254	bool
255	default y
256
257config AS_HAS_EXPLICIT_RELOCS
258	def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x))
259
260config AS_HAS_FCSR_CLASS
261	def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0)
262
263config AS_HAS_LSX_EXTENSION
264	def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0)
265
266config AS_HAS_LASX_EXTENSION
267	def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0)
268
269config AS_HAS_LBT_EXTENSION
270	def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0)
271
272config AS_HAS_LVZ_EXTENSION
273	def_bool $(as-instr,hvcl 0)
274
275menu "Kernel type and options"
276
277source "kernel/Kconfig.hz"
278
279choice
280	prompt "Page Table Layout"
281	default 16KB_2LEVEL if 32BIT
282	default 16KB_3LEVEL if 64BIT
283	help
284	  Allows choosing the page table layout, which is a combination
285	  of page size and page table levels. The size of virtual memory
286	  address space are determined by the page table layout.
287
288config 4KB_3LEVEL
289	bool "4KB with 3 levels"
290	select HAVE_PAGE_SIZE_4KB
291	select PGTABLE_3LEVEL
292	help
293	  This option selects 4KB page size with 3 level page tables, which
294	  support a maximum of 39 bits of application virtual memory.
295
296config 4KB_4LEVEL
297	bool "4KB with 4 levels"
298	select HAVE_PAGE_SIZE_4KB
299	select PGTABLE_4LEVEL
300	help
301	  This option selects 4KB page size with 4 level page tables, which
302	  support a maximum of 48 bits of application virtual memory.
303
304config 16KB_2LEVEL
305	bool "16KB with 2 levels"
306	select HAVE_PAGE_SIZE_16KB
307	select PGTABLE_2LEVEL
308	help
309	  This option selects 16KB page size with 2 level page tables, which
310	  support a maximum of 36 bits of application virtual memory.
311
312config 16KB_3LEVEL
313	bool "16KB with 3 levels"
314	select HAVE_PAGE_SIZE_16KB
315	select PGTABLE_3LEVEL
316	help
317	  This option selects 16KB page size with 3 level page tables, which
318	  support a maximum of 47 bits of application virtual memory.
319
320config 64KB_2LEVEL
321	bool "64KB with 2 levels"
322	select HAVE_PAGE_SIZE_64KB
323	select PGTABLE_2LEVEL
324	help
325	  This option selects 64KB page size with 2 level page tables, which
326	  support a maximum of 42 bits of application virtual memory.
327
328config 64KB_3LEVEL
329	bool "64KB with 3 levels"
330	select HAVE_PAGE_SIZE_64KB
331	select PGTABLE_3LEVEL
332	help
333	  This option selects 64KB page size with 3 level page tables, which
334	  support a maximum of 55 bits of application virtual memory.
335
336endchoice
337
338config CMDLINE
339	string "Built-in kernel command line"
340	help
341	  For most platforms, the arguments for the kernel's command line
342	  are provided at run-time, during boot. However, there are cases
343	  where either no arguments are being provided or the provided
344	  arguments are insufficient or even invalid.
345
346	  When that occurs, it is possible to define a built-in command
347	  line here and choose how the kernel should use it later on.
348
349choice
350	prompt "Kernel command line type"
351	default CMDLINE_BOOTLOADER
352	help
353	  Choose how the kernel will handle the provided built-in command
354	  line.
355
356config CMDLINE_BOOTLOADER
357	bool "Use bootloader kernel arguments if available"
358	help
359	  Prefer the command-line passed by the boot loader if available.
360	  Use the built-in command line as fallback in case we get nothing
361	  during boot. This is the default behaviour.
362
363config CMDLINE_EXTEND
364	bool "Use built-in to extend bootloader kernel arguments"
365	help
366	  The command-line arguments provided during boot will be
367	  appended to the built-in command line. This is useful in
368	  cases where the provided arguments are insufficient and
369	  you don't want to or cannot modify them.
370
371config CMDLINE_FORCE
372	bool "Always use the built-in kernel command string"
373	help
374	  Always use the built-in command line, even if we get one during
375	  boot. This is useful in case you need to override the provided
376	  command line on systems where you don't have or want control
377	  over it.
378
379endchoice
380
381config BUILTIN_DTB
382	bool "Enable built-in dtb in kernel"
383	depends on OF
384	help
385	  Some existing systems do not provide a canonical device tree to
386	  the kernel at boot time. Let's provide a device tree table in the
387	  kernel, keyed by the dts filename, containing the relevant DTBs.
388
389	  Built-in DTBs are generic enough and can be used as references.
390
391config BUILTIN_DTB_NAME
392	string "Source file for built-in dtb"
393	depends on BUILTIN_DTB
394	help
395	  Base name (without suffix, relative to arch/loongarch/boot/dts/)
396	  for the DTS file that will be used to produce the DTB linked into
397	  the kernel.
398
399config DMI
400	bool "Enable DMI scanning"
401	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
402	default y
403	help
404	  This enables SMBIOS/DMI feature for systems, and scanning of
405	  DMI to identify machine quirks.
406
407config EFI
408	bool "EFI runtime service support"
409	select UCS2_STRING
410	select EFI_RUNTIME_WRAPPERS
411	help
412	  This enables the kernel to use EFI runtime services that are
413	  available (such as the EFI variable services).
414
415config EFI_STUB
416	bool "EFI boot stub support"
417	default y
418	depends on EFI
419	select EFI_GENERIC_STUB
420	help
421	  This kernel feature allows the kernel to be loaded directly by
422	  EFI firmware without the use of a bootloader.
423
424config SCHED_SMT
425	bool "SMT scheduler support"
426	depends on SMP
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_RESERVE
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
637source "kernel/livepatch/Kconfig"
638
639endmenu
640
641config ARCH_SELECT_MEMORY_MODEL
642	def_bool y
643
644config ARCH_FLATMEM_ENABLE
645	def_bool y
646	depends on !NUMA
647
648config ARCH_SPARSEMEM_ENABLE
649	def_bool y
650	select SPARSEMEM_VMEMMAP_ENABLE
651	help
652	  Say Y to support efficient handling of sparse physical memory,
653	  for architectures which are either NUMA (Non-Uniform Memory Access)
654	  or have huge holes in the physical address space for other reasons.
655	  See <file:Documentation/mm/numa.rst> for more.
656
657config ARCH_MEMORY_PROBE
658	def_bool y
659	depends on MEMORY_HOTPLUG
660
661config MMU
662	bool
663	default y
664
665config ARCH_MMAP_RND_BITS_MIN
666	default 12
667
668config ARCH_MMAP_RND_BITS_MAX
669	default 18
670
671config ARCH_SUPPORTS_UPROBES
672	def_bool y
673
674config KASAN_SHADOW_OFFSET
675	hex
676	default 0x0
677	depends on KASAN
678
679menu "Power management options"
680
681config ARCH_SUSPEND_POSSIBLE
682	def_bool y
683
684config ARCH_HIBERNATION_POSSIBLE
685	def_bool y
686
687source "kernel/power/Kconfig"
688source "drivers/acpi/Kconfig"
689
690endmenu
691
692source "arch/loongarch/kvm/Kconfig"
693