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_NEEDS_DEFER_KASAN 13 select ARCH_DISABLE_KASAN_INLINE 14 select ARCH_ENABLE_MEMORY_HOTPLUG 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_PER_VMA_LOCK 73 select ARCH_SUPPORTS_RT 74 select ARCH_SUPPORTS_SCHED_SMT if SMP 75 select ARCH_SUPPORTS_SCHED_MC if SMP 76 select ARCH_USE_BUILTIN_BSWAP 77 select ARCH_USE_CMPXCHG_LOCKREF 78 select ARCH_USE_MEMTEST 79 select ARCH_USE_QUEUED_RWLOCKS 80 select ARCH_USE_QUEUED_SPINLOCKS 81 select ARCH_WANT_DEFAULT_BPF_JIT 82 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 83 select ARCH_WANT_LD_ORPHAN_WARN 84 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 85 select ARCH_WANTS_NO_INSTR 86 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 87 select BUILDTIME_TABLE_SORT 88 select COMMON_CLK 89 select CPU_PM 90 select EDAC_SUPPORT 91 select EFI 92 select GENERIC_CLOCKEVENTS 93 select GENERIC_CMOS_UPDATE 94 select GENERIC_CPU_AUTOPROBE 95 select GENERIC_CPU_DEVICES 96 select GENERIC_CPU_VULNERABILITIES 97 select GENERIC_ENTRY 98 select GENERIC_GETTIMEOFDAY 99 select GENERIC_IOREMAP if !ARCH_IOREMAP 100 select GENERIC_IRQ_MATRIX_ALLOCATOR 101 select GENERIC_IRQ_MULTI_HANDLER 102 select GENERIC_IRQ_PROBE 103 select GENERIC_IRQ_SHOW 104 select GENERIC_LIB_ASHLDI3 105 select GENERIC_LIB_ASHRDI3 106 select GENERIC_LIB_CMPDI2 107 select GENERIC_LIB_LSHRDI3 108 select GENERIC_LIB_UCMPDI2 109 select GENERIC_LIB_DEVMEM_IS_ALLOWED 110 select GENERIC_PCI_IOMAP 111 select GENERIC_SCHED_CLOCK 112 select GENERIC_SMP_IDLE_THREAD 113 select GENERIC_TIME_VSYSCALL 114 select GPIOLIB 115 select HAS_IOPORT 116 select HAVE_ALIGNED_STRUCT_PAGE 117 select HAVE_ARCH_AUDITSYSCALL 118 select HAVE_ARCH_BITREVERSE 119 select HAVE_ARCH_JUMP_LABEL 120 select HAVE_ARCH_JUMP_LABEL_RELATIVE 121 select HAVE_ARCH_KASAN 122 select HAVE_ARCH_KFENCE 123 select HAVE_ARCH_KGDB if PERF_EVENTS 124 select HAVE_ARCH_KSTACK_ERASE 125 select HAVE_ARCH_MMAP_RND_BITS if MMU 126 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 127 select HAVE_ARCH_SECCOMP 128 select HAVE_ARCH_SECCOMP_FILTER 129 select HAVE_ARCH_TRACEHOOK 130 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 131 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD 132 select HAVE_ASM_MODVERSIONS 133 select HAVE_CMPXCHG_DOUBLE 134 select HAVE_CMPXCHG_LOCAL 135 select HAVE_CONTEXT_TRACKING_USER 136 select HAVE_C_RECORDMCOUNT 137 select HAVE_DEBUG_KMEMLEAK 138 select HAVE_DEBUG_STACKOVERFLOW 139 select HAVE_DMA_CONTIGUOUS 140 select HAVE_DYNAMIC_FTRACE 141 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 142 select HAVE_FTRACE_REGS_HAVING_PT_REGS 143 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 144 select HAVE_DYNAMIC_FTRACE_WITH_REGS 145 select HAVE_EBPF_JIT 146 select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN 147 select HAVE_EXIT_THREAD 148 select HAVE_GENERIC_TIF_BITS 149 select HAVE_GUP_FAST 150 select HAVE_FTRACE_GRAPH_FUNC 151 select HAVE_FUNCTION_ARG_ACCESS_API 152 select HAVE_FUNCTION_ERROR_INJECTION 153 select HAVE_FUNCTION_GRAPH_FREGS 154 select HAVE_FUNCTION_GRAPH_TRACER 155 select HAVE_FUNCTION_TRACER 156 select HAVE_GCC_PLUGINS 157 select HAVE_GENERIC_VDSO 158 select HAVE_HW_BREAKPOINT if PERF_EVENTS 159 select HAVE_IOREMAP_PROT 160 select HAVE_IRQ_EXIT_ON_IRQ_STACK 161 select HAVE_IRQ_TIME_ACCOUNTING 162 select HAVE_KPROBES 163 select HAVE_KPROBES_ON_FTRACE 164 select HAVE_KRETPROBES 165 select HAVE_LIVEPATCH 166 select HAVE_MOD_ARCH_SPECIFIC 167 select HAVE_NMI 168 select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS && AS_HAS_THIN_ADD_SUB 169 select HAVE_PCI 170 select HAVE_PERF_EVENTS 171 select HAVE_PERF_REGS 172 select HAVE_PERF_USER_STACK_DUMP 173 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 174 select HAVE_PREEMPT_DYNAMIC_KEY 175 select HAVE_REGS_AND_STACK_ACCESS_API 176 select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC 177 select HAVE_RETHOOK 178 select HAVE_RSEQ 179 select HAVE_RUST 180 select HAVE_SAMPLE_FTRACE_DIRECT 181 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 182 select HAVE_SETUP_PER_CPU_AREA if NUMA 183 select HAVE_STACK_VALIDATION if HAVE_OBJTOOL 184 select HAVE_STACKPROTECTOR 185 select HAVE_SYSCALL_TRACEPOINTS 186 select HAVE_TIF_NOHZ 187 select HAVE_VIRT_CPU_ACCOUNTING_GEN 188 select HOTPLUG_SMT if HOTPLUG_CPU 189 select IRQ_FORCED_THREADING 190 select IRQ_LOONGARCH_CPU 191 select LOCK_MM_AND_FIND_VMA 192 select MMU_GATHER_MERGE_VMAS if MMU 193 select MMU_GATHER_RCU_TABLE_FREE 194 select MODULES_USE_ELF_RELA if MODULES 195 select NEED_PER_CPU_EMBED_FIRST_CHUNK 196 select NEED_PER_CPU_PAGE_FIRST_CHUNK 197 select NUMA_MEMBLKS if NUMA 198 select OF 199 select OF_EARLY_FLATTREE 200 select PCI 201 select PCI_DOMAINS_GENERIC 202 select PCI_ECAM if ACPI 203 select PCI_LOONGSON 204 select PCI_MSI_ARCH_FALLBACKS 205 select PCI_QUIRKS 206 select PERF_USE_VMALLOC 207 select RTC_LIB 208 select SPARSE_IRQ 209 select SYSCTL_ARCH_UNALIGN_ALLOW 210 select SYSCTL_ARCH_UNALIGN_NO_WARN 211 select SYSCTL_EXCEPTION_TRACE 212 select SWIOTLB 213 select TRACE_IRQFLAGS_SUPPORT 214 select USE_PERCPU_NUMA_NODE_ID 215 select USER_STACKTRACE_SUPPORT 216 select VDSO_GETRANDOM 217 select ZONE_DMA32 218 219config 32BIT 220 bool 221 222config 64BIT 223 def_bool y 224 225config GENERIC_BUG 226 def_bool y 227 depends on BUG 228 229config GENERIC_BUG_RELATIVE_POINTERS 230 def_bool y 231 depends on GENERIC_BUG 232 233config GENERIC_CALIBRATE_DELAY 234 def_bool y 235 236config GENERIC_CSUM 237 def_bool y 238 239config GENERIC_HWEIGHT 240 def_bool y 241 242config L1_CACHE_SHIFT 243 int 244 default "6" 245 246config LOCKDEP_SUPPORT 247 bool 248 default y 249 250config STACKTRACE_SUPPORT 251 bool 252 default y 253 254# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the 255# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that 256# are shared between architectures, and specifically expecting the symbols. 257config MACH_LOONGSON32 258 def_bool 32BIT 259 260config MACH_LOONGSON64 261 def_bool 64BIT 262 263config FIX_EARLYCON_MEM 264 def_bool !ARCH_IOREMAP 265 266config PGTABLE_2LEVEL 267 bool 268 269config PGTABLE_3LEVEL 270 bool 271 272config PGTABLE_4LEVEL 273 bool 274 275config PGTABLE_LEVELS 276 int 277 default 2 if PGTABLE_2LEVEL 278 default 3 if PGTABLE_3LEVEL 279 default 4 if PGTABLE_4LEVEL 280 281config SCHED_OMIT_FRAME_POINTER 282 bool 283 default y 284 285config AS_HAS_EXPLICIT_RELOCS 286 def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x)) 287 288config AS_HAS_FCSR_CLASS 289 def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0) 290 291config AS_HAS_THIN_ADD_SUB 292 def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) || AS_IS_LLVM 293 294config AS_HAS_LSX_EXTENSION 295 def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0) 296 297config AS_HAS_LASX_EXTENSION 298 def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0) 299 300config AS_HAS_LBT_EXTENSION 301 def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0) 302 303config AS_HAS_LVZ_EXTENSION 304 def_bool $(as-instr,hvcl 0) 305 306config AS_HAS_SCQ_EXTENSION 307 def_bool $(as-instr,sc.q \$t0$(comma)\$t1$(comma)\$t2) 308 309config CC_HAS_ANNOTATE_TABLEJUMP 310 def_bool $(cc-option,-mannotate-tablejump) 311 312config RUSTC_HAS_ANNOTATE_TABLEJUMP 313 depends on RUST 314 def_bool $(rustc-option,-Cllvm-args=--loongarch-annotate-tablejump) 315 316menu "Kernel type and options" 317 318source "kernel/Kconfig.hz" 319 320choice 321 prompt "Page Table Layout" 322 default 16KB_2LEVEL if 32BIT 323 default 16KB_3LEVEL if 64BIT 324 help 325 Allows choosing the page table layout, which is a combination 326 of page size and page table levels. The size of virtual memory 327 address space are determined by the page table layout. 328 329config 4KB_3LEVEL 330 bool "4KB with 3 levels" 331 select HAVE_PAGE_SIZE_4KB 332 select PGTABLE_3LEVEL 333 help 334 This option selects 4KB page size with 3 level page tables, which 335 support a maximum of 39 bits of application virtual memory. 336 337config 4KB_4LEVEL 338 bool "4KB with 4 levels" 339 select HAVE_PAGE_SIZE_4KB 340 select PGTABLE_4LEVEL 341 help 342 This option selects 4KB page size with 4 level page tables, which 343 support a maximum of 48 bits of application virtual memory. 344 345config 16KB_2LEVEL 346 bool "16KB with 2 levels" 347 select HAVE_PAGE_SIZE_16KB 348 select PGTABLE_2LEVEL 349 help 350 This option selects 16KB page size with 2 level page tables, which 351 support a maximum of 36 bits of application virtual memory. 352 353config 16KB_3LEVEL 354 bool "16KB with 3 levels" 355 select HAVE_PAGE_SIZE_16KB 356 select PGTABLE_3LEVEL 357 help 358 This option selects 16KB page size with 3 level page tables, which 359 support a maximum of 47 bits of application virtual memory. 360 361config 64KB_2LEVEL 362 bool "64KB with 2 levels" 363 select HAVE_PAGE_SIZE_64KB 364 select PGTABLE_2LEVEL 365 help 366 This option selects 64KB page size with 2 level page tables, which 367 support a maximum of 42 bits of application virtual memory. 368 369config 64KB_3LEVEL 370 bool "64KB with 3 levels" 371 select HAVE_PAGE_SIZE_64KB 372 select PGTABLE_3LEVEL 373 help 374 This option selects 64KB page size with 3 level page tables, which 375 support a maximum of 55 bits of application virtual memory. 376 377endchoice 378 379config CMDLINE 380 string "Built-in kernel command line" 381 help 382 For most platforms, the arguments for the kernel's command line 383 are provided at run-time, during boot. However, there are cases 384 where either no arguments are being provided or the provided 385 arguments are insufficient or even invalid. 386 387 When that occurs, it is possible to define a built-in command 388 line here and choose how the kernel should use it later on. 389 390choice 391 prompt "Kernel command line type" 392 default CMDLINE_BOOTLOADER 393 help 394 Choose how the kernel will handle the provided built-in command 395 line. 396 397config CMDLINE_BOOTLOADER 398 bool "Use bootloader kernel arguments if available" 399 help 400 Prefer the command-line passed by the boot loader if available. 401 Use the built-in command line as fallback in case we get nothing 402 during boot. This is the default behaviour. 403 404config CMDLINE_EXTEND 405 bool "Use built-in to extend bootloader kernel arguments" 406 help 407 The built-in command line will be appended to the command- 408 line arguments provided during boot. This is useful in 409 cases where the provided arguments are insufficient and 410 you don't want to or cannot modify them. 411 412config CMDLINE_FORCE 413 bool "Always use the built-in kernel command string" 414 help 415 Always use the built-in command line, even if we get one during 416 boot. This is useful in case you need to override the provided 417 command line on systems where you don't have or want control 418 over it. 419 420endchoice 421 422config BUILTIN_DTB 423 bool "Enable built-in dtb in kernel" 424 depends on OF 425 select GENERIC_BUILTIN_DTB 426 help 427 Some existing systems do not provide a canonical device tree to 428 the kernel at boot time. Let's provide a device tree table in the 429 kernel, keyed by the dts filename, containing the relevant DTBs. 430 431 Built-in DTBs are generic enough and can be used as references. 432 433config BUILTIN_DTB_NAME 434 string "Source file for built-in dtb" 435 depends on BUILTIN_DTB 436 help 437 Base name (without suffix, relative to arch/loongarch/boot/dts/) 438 for the DTS file that will be used to produce the DTB linked into 439 the kernel. 440 441config DMI 442 bool "Enable DMI scanning" 443 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 444 default y 445 help 446 This enables SMBIOS/DMI feature for systems, and scanning of 447 DMI to identify machine quirks. 448 449config EFI 450 bool "EFI runtime service support" 451 select UCS2_STRING 452 select EFI_RUNTIME_WRAPPERS 453 help 454 This enables the kernel to use EFI runtime services that are 455 available (such as the EFI variable services). 456 457config EFI_STUB 458 bool "EFI boot stub support" 459 default y 460 depends on EFI 461 select EFI_GENERIC_STUB 462 help 463 This kernel feature allows the kernel to be loaded directly by 464 EFI firmware without the use of a bootloader. 465 466config SMP 467 bool "Multi-Processing support" 468 help 469 This enables support for systems with more than one CPU. If you have 470 a system with only one CPU, say N. If you have a system with more 471 than one CPU, say Y. 472 473 If you say N here, the kernel will run on uni- and multiprocessor 474 machines, but will use only one CPU of a multiprocessor machine. If 475 you say Y here, the kernel will run on many, but not all, 476 uniprocessor machines. On a uniprocessor machine, the kernel 477 will run faster if you say N here. 478 479 See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. 480 481 If you don't know what to do here, say N. 482 483config HOTPLUG_CPU 484 bool "Support for hot-pluggable CPUs" 485 depends on SMP 486 select GENERIC_IRQ_MIGRATION 487 help 488 Say Y here to allow turning CPUs off and on. CPUs can be 489 controlled through /sys/devices/system/cpu. 490 (Note: power management support will enable this option 491 automatically on SMP systems. ) 492 Say N if you want to disable CPU hotplug. 493 494config NR_CPUS 495 int "Maximum number of CPUs (2-2048)" 496 range 2 2048 497 default "2048" 498 depends on SMP 499 help 500 This allows you to specify the maximum number of CPUs which this 501 kernel will support. 502 503config NUMA 504 bool "NUMA Support" 505 select SMP 506 help 507 Say Y to compile the kernel with NUMA (Non-Uniform Memory Access) 508 support. This option improves performance on systems with more 509 than one NUMA node; on single node systems it is generally better 510 to leave it disabled. 511 512config NODES_SHIFT 513 int 514 default "6" 515 depends on NUMA 516 517config ARCH_FORCE_MAX_ORDER 518 int "Maximum zone order" 519 default "13" if PAGE_SIZE_64KB 520 default "11" if PAGE_SIZE_16KB 521 default "10" 522 help 523 The kernel memory allocator divides physically contiguous memory 524 blocks into "zones", where each zone is a power of two number of 525 pages. This option selects the largest power of two that the kernel 526 keeps in the memory allocator. If you need to allocate very large 527 blocks of physically contiguous memory, then you may need to 528 increase this value. 529 530 The page size is not necessarily 4KB. Keep this in mind 531 when choosing a value for this option. 532 533config ARCH_IOREMAP 534 bool "Enable LoongArch DMW-based ioremap()" 535 help 536 We use generic TLB-based ioremap() by default since it has page 537 protection support. However, you can enable LoongArch DMW-based 538 ioremap() for better performance. 539 540config ARCH_WRITECOMBINE 541 bool "Enable WriteCombine (WUC) for ioremap()" 542 help 543 LoongArch maintains cache coherency in hardware, but when paired 544 with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which 545 is similar to WriteCombine) is out of the scope of cache coherency 546 machanism for PCIe devices (this is a PCIe protocol violation, which 547 may be fixed in newer chipsets). 548 549 This means WUC can only used for write-only memory regions now, so 550 this option is disabled by default, making WUC silently fallback to 551 SUC for ioremap(). You can enable this option if the kernel is ensured 552 to run on hardware without this bug. 553 554 You can override this setting via writecombine=on/off boot parameter. 555 556config ARCH_STRICT_ALIGN 557 bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT 558 default y 559 help 560 Not all LoongArch cores support h/w unaligned access, we can use 561 -mstrict-align build parameter to prevent unaligned accesses. 562 563 CPUs with h/w unaligned access support: 564 Loongson-2K2000/2K3000 and all of Loongson-3 series processors 565 based on LoongArch. 566 567 CPUs without h/w unaligned access support: 568 Loongson-2K0300/2K0500/2K1000. 569 570 If you want to make sure whether to support unaligned memory access 571 on your hardware, please read the bit 20 (UAL) of CPUCFG1 register. 572 573 This option is enabled by default to make the kernel be able to run 574 on all LoongArch systems. But you can disable it manually if you want 575 to run kernel only on systems with h/w unaligned access support in 576 order to optimise for performance. 577 578config CPU_HAS_AMO 579 bool 580 default 64BIT 581 582config CPU_HAS_FPU 583 bool 584 default y 585 586config CPU_HAS_LSX 587 bool "Support for the Loongson SIMD Extension" 588 depends on AS_HAS_LSX_EXTENSION 589 help 590 Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers 591 and a set of SIMD instructions to operate on them. When this option 592 is enabled the kernel will support allocating & switching LSX 593 vector register contexts. If you know that your kernel will only be 594 running on CPUs which do not support LSX or that your userland will 595 not be making use of it then you may wish to say N here to reduce 596 the size & complexity of your kernel. 597 598 If unsure, say Y. 599 600config CPU_HAS_LASX 601 bool "Support for the Loongson Advanced SIMD Extension" 602 depends on CPU_HAS_LSX 603 depends on AS_HAS_LASX_EXTENSION 604 help 605 Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector 606 registers and a set of SIMD instructions to operate on them. When this 607 option is enabled the kernel will support allocating & switching LASX 608 vector register contexts. If you know that your kernel will only be 609 running on CPUs which do not support LASX or that your userland will 610 not be making use of it then you may wish to say N here to reduce 611 the size & complexity of your kernel. 612 613 If unsure, say Y. 614 615config CPU_HAS_LBT 616 bool "Support for the Loongson Binary Translation Extension" 617 depends on AS_HAS_LBT_EXTENSION 618 help 619 Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0 620 to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). 621 Enabling this option allows the kernel to allocate and switch registers 622 specific to LBT. 623 624 If you want to use this feature, such as the Loongson Architecture 625 Translator (LAT), say Y. 626 627config CPU_HAS_PREFETCH 628 bool 629 default y 630 631config ARCH_SUPPORTS_KEXEC 632 def_bool y 633 634config ARCH_SUPPORTS_KEXEC_FILE 635 def_bool 64BIT 636 637config ARCH_SELECTS_KEXEC_FILE 638 def_bool 64BIT 639 depends on KEXEC_FILE 640 select KEXEC_ELF 641 select RELOCATABLE 642 select HAVE_IMA_KEXEC if IMA 643 644config ARCH_SUPPORTS_CRASH_DUMP 645 def_bool y 646 647config ARCH_DEFAULT_CRASH_DUMP 648 def_bool y 649 650config ARCH_SELECTS_CRASH_DUMP 651 def_bool y 652 depends on CRASH_DUMP 653 select RELOCATABLE 654 655config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 656 def_bool CRASH_RESERVE 657 658config RELOCATABLE 659 bool "Relocatable kernel" 660 select ARCH_HAS_RELR 661 help 662 This builds the kernel as a Position Independent Executable (PIE), 663 which retains all relocation metadata required, so as to relocate 664 the kernel binary at runtime to a different virtual address from 665 its link address. 666 667config RANDOMIZE_BASE 668 bool "Randomize the address of the kernel (KASLR)" 669 depends on RELOCATABLE 670 help 671 Randomizes the physical and virtual address at which the 672 kernel image is loaded, as a security feature that 673 deters exploit attempts relying on knowledge of the location 674 of kernel internals. 675 676 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET. 677 678 If unsure, say N. 679 680config RANDOMIZE_BASE_MAX_OFFSET 681 hex "Maximum KASLR offset" if EXPERT 682 depends on RANDOMIZE_BASE 683 range 0x0 0x10000000 684 default "0x01000000" 685 help 686 When KASLR is active, this provides the maximum offset that will 687 be applied to the kernel image. It should be set according to the 688 amount of physical RAM available in the target system. 689 690 This is limited by the size of the lower address memory, 256MB. 691 692source "kernel/livepatch/Kconfig" 693 694config PARAVIRT 695 bool "Enable paravirtualization code" 696 depends on AS_HAS_LVZ_EXTENSION 697 select HAVE_PV_STEAL_CLOCK_GEN 698 help 699 This changes the kernel so it can modify itself when it is run 700 under a hypervisor, potentially improving performance significantly 701 over full virtualization. However, when run without a hypervisor 702 the kernel is theoretically slower and slightly larger. 703 704config PARAVIRT_TIME_ACCOUNTING 705 bool "Paravirtual steal time accounting" 706 depends on PARAVIRT 707 help 708 Select this option to enable fine granularity task steal time 709 accounting. Time spent executing other tasks in parallel with 710 the current vCPU is discounted from the vCPU power. To account for 711 that, there can be a small performance impact. 712 713 If in doubt, say N here. 714 715endmenu 716 717config ARCH_SELECT_MEMORY_MODEL 718 def_bool y 719 720config ARCH_FLATMEM_ENABLE 721 def_bool y 722 depends on !NUMA 723 724config ARCH_SPARSEMEM_ENABLE 725 def_bool y 726 select SPARSEMEM_VMEMMAP_ENABLE 727 help 728 Say Y to support efficient handling of sparse physical memory, 729 for architectures which are either NUMA (Non-Uniform Memory Access) 730 or have huge holes in the physical address space for other reasons. 731 See <file:Documentation/mm/numa.rst> for more. 732 733config ARCH_MEMORY_PROBE 734 def_bool y 735 depends on MEMORY_HOTPLUG 736 737config MMU 738 bool 739 default y 740 741config ARCH_MMAP_RND_BITS_MIN 742 default 12 743 744config ARCH_MMAP_RND_BITS_MAX 745 default 18 746 747config ARCH_SUPPORTS_UPROBES 748 def_bool y 749 750config KASAN_SHADOW_OFFSET 751 hex 752 default 0x0 753 depends on KASAN 754 755menu "Power management options" 756 757config ARCH_SUSPEND_POSSIBLE 758 def_bool y 759 760config ARCH_HIBERNATION_POSSIBLE 761 def_bool y 762 763source "kernel/power/Kconfig" 764source "drivers/acpi/Kconfig" 765source "drivers/cpufreq/Kconfig" 766 767endmenu 768 769source "arch/loongarch/kvm/Kconfig" 770