xref: /linux/arch/loongarch/Kconfig (revision 30bbcb44707a97fcb62246bebc8b413b5ab293f8)
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_DEBUG_VM_PGTABLE
20	select ARCH_HAS_FAST_MULTIPLIER
21	select ARCH_HAS_FORTIFY_SOURCE
22	select ARCH_HAS_KCOV
23	select ARCH_HAS_KERNEL_FPU_SUPPORT if CPU_HAS_FPU
24	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
25	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
26	select ARCH_HAS_PREEMPT_LAZY
27	select ARCH_HAS_PTE_SPECIAL
28	select ARCH_HAS_SET_MEMORY
29	select ARCH_HAS_SET_DIRECT_MAP
30	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
31	select ARCH_HAS_UBSAN
32	select ARCH_HAS_VDSO_ARCH_DATA
33	select ARCH_INLINE_READ_LOCK if !PREEMPTION
34	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
35	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
36	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
37	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
38	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
39	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
40	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
41	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
42	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
43	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
44	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
45	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
46	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
47	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
48	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
49	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
50	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
51	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
52	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
53	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
54	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
55	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
56	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
57	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
58	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
59	select ARCH_KEEP_MEMBLOCK
60	select ARCH_MIGHT_HAVE_PC_PARPORT
61	select ARCH_MIGHT_HAVE_PC_SERIO
62	select ARCH_SPARSEMEM_ENABLE
63	select ARCH_STACKWALK
64	select ARCH_SUPPORTS_ACPI
65	select ARCH_SUPPORTS_ATOMIC_RMW
66	select ARCH_SUPPORTS_HUGETLBFS
67	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
68	select ARCH_SUPPORTS_LTO_CLANG
69	select ARCH_SUPPORTS_LTO_CLANG_THIN
70	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
71	select ARCH_SUPPORTS_NUMA_BALANCING
72	select ARCH_SUPPORTS_RT
73	select ARCH_SUPPORTS_SCHED_SMT if SMP
74	select ARCH_SUPPORTS_SCHED_MC  if SMP
75	select ARCH_USE_BUILTIN_BSWAP
76	select ARCH_USE_CMPXCHG_LOCKREF
77	select ARCH_USE_MEMTEST
78	select ARCH_USE_QUEUED_RWLOCKS
79	select ARCH_USE_QUEUED_SPINLOCKS
80	select ARCH_WANT_DEFAULT_BPF_JIT
81	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
82	select ARCH_WANT_LD_ORPHAN_WARN
83	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
84	select ARCH_WANTS_NO_INSTR
85	select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE
86	select BUILDTIME_TABLE_SORT
87	select COMMON_CLK
88	select CPU_PM
89	select EDAC_SUPPORT
90	select EFI
91	select GENERIC_CLOCKEVENTS
92	select GENERIC_CMOS_UPDATE
93	select GENERIC_CPU_AUTOPROBE
94	select GENERIC_CPU_DEVICES
95	select GENERIC_CPU_VULNERABILITIES
96	select GENERIC_ENTRY
97	select GENERIC_GETTIMEOFDAY
98	select GENERIC_IOREMAP if !ARCH_IOREMAP
99	select GENERIC_IRQ_MATRIX_ALLOCATOR
100	select GENERIC_IRQ_MULTI_HANDLER
101	select GENERIC_IRQ_PROBE
102	select GENERIC_IRQ_SHOW
103	select GENERIC_LIB_ASHLDI3
104	select GENERIC_LIB_ASHRDI3
105	select GENERIC_LIB_CMPDI2
106	select GENERIC_LIB_LSHRDI3
107	select GENERIC_LIB_UCMPDI2
108	select GENERIC_LIB_DEVMEM_IS_ALLOWED
109	select GENERIC_PCI_IOMAP
110	select GENERIC_SCHED_CLOCK
111	select GENERIC_SMP_IDLE_THREAD
112	select GENERIC_TIME_VSYSCALL
113	select GPIOLIB
114	select HAS_IOPORT
115	select HAVE_ARCH_AUDITSYSCALL
116	select HAVE_ARCH_JUMP_LABEL
117	select HAVE_ARCH_JUMP_LABEL_RELATIVE
118	select HAVE_ARCH_KASAN
119	select HAVE_ARCH_KFENCE
120	select HAVE_ARCH_KGDB if PERF_EVENTS
121	select HAVE_ARCH_KSTACK_ERASE
122	select HAVE_ARCH_MMAP_RND_BITS if MMU
123	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
124	select HAVE_ARCH_SECCOMP
125	select HAVE_ARCH_SECCOMP_FILTER
126	select HAVE_ARCH_TRACEHOOK
127	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
128	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
129	select HAVE_ASM_MODVERSIONS
130	select HAVE_CONTEXT_TRACKING_USER
131	select HAVE_C_RECORDMCOUNT
132	select HAVE_DEBUG_KMEMLEAK
133	select HAVE_DEBUG_STACKOVERFLOW
134	select HAVE_DMA_CONTIGUOUS
135	select HAVE_DYNAMIC_FTRACE
136	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
137	select HAVE_FTRACE_REGS_HAVING_PT_REGS
138	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
139	select HAVE_DYNAMIC_FTRACE_WITH_REGS
140	select HAVE_EBPF_JIT
141	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
142	select HAVE_EXIT_THREAD
143	select HAVE_GENERIC_TIF_BITS
144	select HAVE_GUP_FAST
145	select HAVE_FTRACE_GRAPH_FUNC
146	select HAVE_FUNCTION_ARG_ACCESS_API
147	select HAVE_FUNCTION_ERROR_INJECTION
148	select HAVE_FUNCTION_GRAPH_FREGS
149	select HAVE_FUNCTION_GRAPH_TRACER
150	select HAVE_FUNCTION_TRACER
151	select HAVE_GCC_PLUGINS
152	select HAVE_GENERIC_VDSO
153	select HAVE_HW_BREAKPOINT if PERF_EVENTS
154	select HAVE_IOREMAP_PROT
155	select HAVE_IRQ_EXIT_ON_IRQ_STACK
156	select HAVE_IRQ_TIME_ACCOUNTING
157	select HAVE_KPROBES
158	select HAVE_KPROBES_ON_FTRACE
159	select HAVE_KRETPROBES
160	select HAVE_LIVEPATCH
161	select HAVE_MOD_ARCH_SPECIFIC
162	select HAVE_NMI
163	select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS && AS_HAS_THIN_ADD_SUB
164	select HAVE_PCI
165	select HAVE_PERF_EVENTS
166	select HAVE_PERF_REGS
167	select HAVE_PERF_USER_STACK_DUMP
168	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
169	select HAVE_PREEMPT_DYNAMIC_KEY
170	select HAVE_REGS_AND_STACK_ACCESS_API
171	select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC
172	select HAVE_RETHOOK
173	select HAVE_RSEQ
174	select HAVE_RUST
175	select HAVE_SAMPLE_FTRACE_DIRECT
176	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
177	select HAVE_SETUP_PER_CPU_AREA if NUMA
178	select HAVE_STACK_VALIDATION if HAVE_OBJTOOL
179	select HAVE_STACKPROTECTOR
180	select HAVE_SYSCALL_TRACEPOINTS
181	select HAVE_TIF_NOHZ
182	select HAVE_VIRT_CPU_ACCOUNTING_GEN
183	select IRQ_FORCED_THREADING
184	select IRQ_LOONGARCH_CPU
185	select LOCK_MM_AND_FIND_VMA
186	select MMU_GATHER_MERGE_VMAS if MMU
187	select MODULES_USE_ELF_RELA if MODULES
188	select NEED_PER_CPU_EMBED_FIRST_CHUNK
189	select NEED_PER_CPU_PAGE_FIRST_CHUNK
190	select NUMA_MEMBLKS if NUMA
191	select OF
192	select OF_EARLY_FLATTREE
193	select PCI
194	select PCI_DOMAINS_GENERIC
195	select PCI_ECAM if ACPI
196	select PCI_LOONGSON
197	select PCI_MSI_ARCH_FALLBACKS
198	select PCI_QUIRKS
199	select PERF_USE_VMALLOC
200	select RTC_LIB
201	select SPARSE_IRQ
202	select SYSCTL_ARCH_UNALIGN_ALLOW
203	select SYSCTL_ARCH_UNALIGN_NO_WARN
204	select SYSCTL_EXCEPTION_TRACE
205	select SWIOTLB
206	select TRACE_IRQFLAGS_SUPPORT
207	select USE_PERCPU_NUMA_NODE_ID
208	select USER_STACKTRACE_SUPPORT
209	select VDSO_GETRANDOM
210	select ZONE_DMA32
211
212config 32BIT
213	bool
214
215config 64BIT
216	def_bool y
217
218config GENERIC_BUG
219	def_bool y
220	depends on BUG
221
222config GENERIC_BUG_RELATIVE_POINTERS
223	def_bool y
224	depends on GENERIC_BUG
225
226config GENERIC_CALIBRATE_DELAY
227	def_bool y
228
229config GENERIC_CSUM
230	def_bool y
231
232config GENERIC_HWEIGHT
233	def_bool y
234
235config L1_CACHE_SHIFT
236	int
237	default "6"
238
239config LOCKDEP_SUPPORT
240	bool
241	default y
242
243config STACKTRACE_SUPPORT
244	bool
245	default y
246
247# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the
248# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
249# are shared between architectures, and specifically expecting the symbols.
250config MACH_LOONGSON32
251	def_bool 32BIT
252
253config MACH_LOONGSON64
254	def_bool 64BIT
255
256config FIX_EARLYCON_MEM
257	def_bool !ARCH_IOREMAP
258
259config PGTABLE_2LEVEL
260	bool
261
262config PGTABLE_3LEVEL
263	bool
264
265config PGTABLE_4LEVEL
266	bool
267
268config PGTABLE_LEVELS
269	int
270	default 2 if PGTABLE_2LEVEL
271	default 3 if PGTABLE_3LEVEL
272	default 4 if PGTABLE_4LEVEL
273
274config SCHED_OMIT_FRAME_POINTER
275	bool
276	default y
277
278config AS_HAS_EXPLICIT_RELOCS
279	def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x))
280
281config AS_HAS_FCSR_CLASS
282	def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0)
283
284config AS_HAS_THIN_ADD_SUB
285	def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) || AS_IS_LLVM
286
287config AS_HAS_LSX_EXTENSION
288	def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0)
289
290config AS_HAS_LASX_EXTENSION
291	def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0)
292
293config AS_HAS_LBT_EXTENSION
294	def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0)
295
296config AS_HAS_LVZ_EXTENSION
297	def_bool $(as-instr,hvcl 0)
298
299config CC_HAS_ANNOTATE_TABLEJUMP
300	def_bool $(cc-option,-mannotate-tablejump)
301
302config RUSTC_HAS_ANNOTATE_TABLEJUMP
303	depends on RUST
304	def_bool $(rustc-option,-Cllvm-args=--loongarch-annotate-tablejump)
305
306menu "Kernel type and options"
307
308source "kernel/Kconfig.hz"
309
310choice
311	prompt "Page Table Layout"
312	default 16KB_2LEVEL if 32BIT
313	default 16KB_3LEVEL if 64BIT
314	help
315	  Allows choosing the page table layout, which is a combination
316	  of page size and page table levels. The size of virtual memory
317	  address space are determined by the page table layout.
318
319config 4KB_3LEVEL
320	bool "4KB with 3 levels"
321	select HAVE_PAGE_SIZE_4KB
322	select PGTABLE_3LEVEL
323	help
324	  This option selects 4KB page size with 3 level page tables, which
325	  support a maximum of 39 bits of application virtual memory.
326
327config 4KB_4LEVEL
328	bool "4KB with 4 levels"
329	select HAVE_PAGE_SIZE_4KB
330	select PGTABLE_4LEVEL
331	help
332	  This option selects 4KB page size with 4 level page tables, which
333	  support a maximum of 48 bits of application virtual memory.
334
335config 16KB_2LEVEL
336	bool "16KB with 2 levels"
337	select HAVE_PAGE_SIZE_16KB
338	select PGTABLE_2LEVEL
339	help
340	  This option selects 16KB page size with 2 level page tables, which
341	  support a maximum of 36 bits of application virtual memory.
342
343config 16KB_3LEVEL
344	bool "16KB with 3 levels"
345	select HAVE_PAGE_SIZE_16KB
346	select PGTABLE_3LEVEL
347	help
348	  This option selects 16KB page size with 3 level page tables, which
349	  support a maximum of 47 bits of application virtual memory.
350
351config 64KB_2LEVEL
352	bool "64KB with 2 levels"
353	select HAVE_PAGE_SIZE_64KB
354	select PGTABLE_2LEVEL
355	help
356	  This option selects 64KB page size with 2 level page tables, which
357	  support a maximum of 42 bits of application virtual memory.
358
359config 64KB_3LEVEL
360	bool "64KB with 3 levels"
361	select HAVE_PAGE_SIZE_64KB
362	select PGTABLE_3LEVEL
363	help
364	  This option selects 64KB page size with 3 level page tables, which
365	  support a maximum of 55 bits of application virtual memory.
366
367endchoice
368
369config CMDLINE
370	string "Built-in kernel command line"
371	help
372	  For most platforms, the arguments for the kernel's command line
373	  are provided at run-time, during boot. However, there are cases
374	  where either no arguments are being provided or the provided
375	  arguments are insufficient or even invalid.
376
377	  When that occurs, it is possible to define a built-in command
378	  line here and choose how the kernel should use it later on.
379
380choice
381	prompt "Kernel command line type"
382	default CMDLINE_BOOTLOADER
383	help
384	  Choose how the kernel will handle the provided built-in command
385	  line.
386
387config CMDLINE_BOOTLOADER
388	bool "Use bootloader kernel arguments if available"
389	help
390	  Prefer the command-line passed by the boot loader if available.
391	  Use the built-in command line as fallback in case we get nothing
392	  during boot. This is the default behaviour.
393
394config CMDLINE_EXTEND
395	bool "Use built-in to extend bootloader kernel arguments"
396	help
397	  The built-in command line will be appended to the command-
398	  line arguments provided during boot. This is useful in
399	  cases where the provided arguments are insufficient and
400	  you don't want to or cannot modify them.
401
402config CMDLINE_FORCE
403	bool "Always use the built-in kernel command string"
404	help
405	  Always use the built-in command line, even if we get one during
406	  boot. This is useful in case you need to override the provided
407	  command line on systems where you don't have or want control
408	  over it.
409
410endchoice
411
412config BUILTIN_DTB
413	bool "Enable built-in dtb in kernel"
414	depends on OF
415	select GENERIC_BUILTIN_DTB
416	help
417	  Some existing systems do not provide a canonical device tree to
418	  the kernel at boot time. Let's provide a device tree table in the
419	  kernel, keyed by the dts filename, containing the relevant DTBs.
420
421	  Built-in DTBs are generic enough and can be used as references.
422
423config BUILTIN_DTB_NAME
424	string "Source file for built-in dtb"
425	depends on BUILTIN_DTB
426	help
427	  Base name (without suffix, relative to arch/loongarch/boot/dts/)
428	  for the DTS file that will be used to produce the DTB linked into
429	  the kernel.
430
431config DMI
432	bool "Enable DMI scanning"
433	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
434	default y
435	help
436	  This enables SMBIOS/DMI feature for systems, and scanning of
437	  DMI to identify machine quirks.
438
439config EFI
440	bool "EFI runtime service support"
441	select UCS2_STRING
442	select EFI_RUNTIME_WRAPPERS
443	help
444	  This enables the kernel to use EFI runtime services that are
445	  available (such as the EFI variable services).
446
447config EFI_STUB
448	bool "EFI boot stub support"
449	default y
450	depends on EFI
451	select EFI_GENERIC_STUB
452	help
453	  This kernel feature allows the kernel to be loaded directly by
454	  EFI firmware without the use of a bootloader.
455
456config SMP
457	bool "Multi-Processing support"
458	help
459	  This enables support for systems with more than one CPU. If you have
460	  a system with only one CPU, say N. If you have a system with more
461	  than one CPU, say Y.
462
463	  If you say N here, the kernel will run on uni- and multiprocessor
464	  machines, but will use only one CPU of a multiprocessor machine. If
465	  you say Y here, the kernel will run on many, but not all,
466	  uniprocessor machines. On a uniprocessor machine, the kernel
467	  will run faster if you say N here.
468
469	  See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>.
470
471	  If you don't know what to do here, say N.
472
473config HOTPLUG_CPU
474	bool "Support for hot-pluggable CPUs"
475	depends on SMP
476	select GENERIC_IRQ_MIGRATION
477	help
478	  Say Y here to allow turning CPUs off and on. CPUs can be
479	  controlled through /sys/devices/system/cpu.
480	  (Note: power management support will enable this option
481	    automatically on SMP systems. )
482	  Say N if you want to disable CPU hotplug.
483
484config NR_CPUS
485	int "Maximum number of CPUs (2-2048)"
486	range 2 2048
487	default "2048"
488	depends on SMP
489	help
490	  This allows you to specify the maximum number of CPUs which this
491	  kernel will support.
492
493config NUMA
494	bool "NUMA Support"
495	select SMP
496	help
497	  Say Y to compile the kernel with NUMA (Non-Uniform Memory Access)
498	  support.  This option improves performance on systems with more
499	  than one NUMA node; on single node systems it is generally better
500	  to leave it disabled.
501
502config NODES_SHIFT
503	int
504	default "6"
505	depends on NUMA
506
507config ARCH_FORCE_MAX_ORDER
508	int "Maximum zone order"
509	default "13" if PAGE_SIZE_64KB
510	default "11" if PAGE_SIZE_16KB
511	default "10"
512	help
513	  The kernel memory allocator divides physically contiguous memory
514	  blocks into "zones", where each zone is a power of two number of
515	  pages.  This option selects the largest power of two that the kernel
516	  keeps in the memory allocator.  If you need to allocate very large
517	  blocks of physically contiguous memory, then you may need to
518	  increase this value.
519
520	  The page size is not necessarily 4KB.  Keep this in mind
521	  when choosing a value for this option.
522
523config ARCH_IOREMAP
524	bool "Enable LoongArch DMW-based ioremap()"
525	help
526	  We use generic TLB-based ioremap() by default since it has page
527	  protection support. However, you can enable LoongArch DMW-based
528	  ioremap() for better performance.
529
530config ARCH_WRITECOMBINE
531	bool "Enable WriteCombine (WUC) for ioremap()"
532	help
533	  LoongArch maintains cache coherency in hardware, but when paired
534	  with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which
535	  is similar to WriteCombine) is out of the scope of cache coherency
536	  machanism for PCIe devices (this is a PCIe protocol violation, which
537	  may be fixed in newer chipsets).
538
539	  This means WUC can only used for write-only memory regions now, so
540	  this option is disabled by default, making WUC silently fallback to
541	  SUC for ioremap(). You can enable this option if the kernel is ensured
542	  to run on hardware without this bug.
543
544	  You can override this setting via writecombine=on/off boot parameter.
545
546config ARCH_STRICT_ALIGN
547	bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT
548	default y
549	help
550	  Not all LoongArch cores support h/w unaligned access, we can use
551	  -mstrict-align build parameter to prevent unaligned accesses.
552
553	  CPUs with h/w unaligned access support:
554	  Loongson-2K2000/2K3000 and all of Loongson-3 series processors
555	  based on LoongArch.
556
557	  CPUs without h/w unaligned access support:
558	  Loongson-2K0300/2K0500/2K1000.
559
560	  If you want to make sure whether to support unaligned memory access
561	  on your hardware, please read the bit 20 (UAL) of CPUCFG1 register.
562
563	  This option is enabled by default to make the kernel be able to run
564	  on all LoongArch systems. But you can disable it manually if you want
565	  to run kernel only on systems with h/w unaligned access support in
566	  order to optimise for performance.
567
568config CPU_HAS_FPU
569	bool
570	default y
571
572config CPU_HAS_LSX
573	bool "Support for the Loongson SIMD Extension"
574	depends on AS_HAS_LSX_EXTENSION
575	help
576	  Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers
577	  and a set of SIMD instructions to operate on them. When this option
578	  is enabled the kernel will support allocating & switching LSX
579	  vector register contexts. If you know that your kernel will only be
580	  running on CPUs which do not support LSX or that your userland will
581	  not be making use of it then you may wish to say N here to reduce
582	  the size & complexity of your kernel.
583
584	  If unsure, say Y.
585
586config CPU_HAS_LASX
587	bool "Support for the Loongson Advanced SIMD Extension"
588	depends on CPU_HAS_LSX
589	depends on AS_HAS_LASX_EXTENSION
590	help
591	  Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector
592	  registers and a set of SIMD instructions to operate on them. When this
593	  option is enabled the kernel will support allocating & switching LASX
594	  vector register contexts. If you know that your kernel will only be
595	  running on CPUs which do not support LASX or that your userland will
596	  not be making use of it then you may wish to say N here to reduce
597	  the size & complexity of your kernel.
598
599	  If unsure, say Y.
600
601config CPU_HAS_LBT
602	bool "Support for the Loongson Binary Translation Extension"
603	depends on AS_HAS_LBT_EXTENSION
604	help
605	  Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0
606	  to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop).
607	  Enabling this option allows the kernel to allocate and switch registers
608	  specific to LBT.
609
610	  If you want to use this feature, such as the Loongson Architecture
611	  Translator (LAT), say Y.
612
613config CPU_HAS_PREFETCH
614	bool
615	default y
616
617config ARCH_SUPPORTS_KEXEC
618	def_bool y
619
620config ARCH_SUPPORTS_CRASH_DUMP
621	def_bool y
622
623config ARCH_DEFAULT_CRASH_DUMP
624	def_bool y
625
626config ARCH_SELECTS_CRASH_DUMP
627	def_bool y
628	depends on CRASH_DUMP
629	select RELOCATABLE
630
631config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
632	def_bool CRASH_RESERVE
633
634config RELOCATABLE
635	bool "Relocatable kernel"
636	select ARCH_HAS_RELR
637	help
638	  This builds the kernel as a Position Independent Executable (PIE),
639	  which retains all relocation metadata required, so as to relocate
640	  the kernel binary at runtime to a different virtual address from
641	  its link address.
642
643config RANDOMIZE_BASE
644	bool "Randomize the address of the kernel (KASLR)"
645	depends on RELOCATABLE
646	help
647	   Randomizes the physical and virtual address at which the
648	   kernel image is loaded, as a security feature that
649	   deters exploit attempts relying on knowledge of the location
650	   of kernel internals.
651
652	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET.
653
654	   If unsure, say N.
655
656config RANDOMIZE_BASE_MAX_OFFSET
657	hex "Maximum KASLR offset" if EXPERT
658	depends on RANDOMIZE_BASE
659	range 0x0 0x10000000
660	default "0x01000000"
661	help
662	  When KASLR is active, this provides the maximum offset that will
663	  be applied to the kernel image. It should be set according to the
664	  amount of physical RAM available in the target system.
665
666	  This is limited by the size of the lower address memory, 256MB.
667
668source "kernel/livepatch/Kconfig"
669
670config PARAVIRT
671	bool "Enable paravirtualization code"
672	depends on AS_HAS_LVZ_EXTENSION
673	help
674	  This changes the kernel so it can modify itself when it is run
675	  under a hypervisor, potentially improving performance significantly
676	  over full virtualization.  However, when run without a hypervisor
677	  the kernel is theoretically slower and slightly larger.
678
679config PARAVIRT_TIME_ACCOUNTING
680	bool "Paravirtual steal time accounting"
681	depends on PARAVIRT
682	help
683	  Select this option to enable fine granularity task steal time
684	  accounting. Time spent executing other tasks in parallel with
685	  the current vCPU is discounted from the vCPU power. To account for
686	  that, there can be a small performance impact.
687
688	  If in doubt, say N here.
689
690endmenu
691
692config ARCH_SELECT_MEMORY_MODEL
693	def_bool y
694
695config ARCH_FLATMEM_ENABLE
696	def_bool y
697	depends on !NUMA
698
699config ARCH_SPARSEMEM_ENABLE
700	def_bool y
701	select SPARSEMEM_VMEMMAP_ENABLE
702	help
703	  Say Y to support efficient handling of sparse physical memory,
704	  for architectures which are either NUMA (Non-Uniform Memory Access)
705	  or have huge holes in the physical address space for other reasons.
706	  See <file:Documentation/mm/numa.rst> for more.
707
708config ARCH_MEMORY_PROBE
709	def_bool y
710	depends on MEMORY_HOTPLUG
711
712config MMU
713	bool
714	default y
715
716config ARCH_MMAP_RND_BITS_MIN
717	default 12
718
719config ARCH_MMAP_RND_BITS_MAX
720	default 18
721
722config ARCH_SUPPORTS_UPROBES
723	def_bool y
724
725config KASAN_SHADOW_OFFSET
726	hex
727	default 0x0
728	depends on KASAN
729
730menu "Power management options"
731
732config ARCH_SUSPEND_POSSIBLE
733	def_bool y
734
735config ARCH_HIBERNATION_POSSIBLE
736	def_bool y
737
738source "kernel/power/Kconfig"
739source "drivers/acpi/Kconfig"
740source "drivers/cpufreq/Kconfig"
741
742endmenu
743
744source "arch/loongarch/kvm/Kconfig"
745