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_MEMORY_HOTREMOVE 16 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 17 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 18 select ARCH_HAS_CPU_FINALIZE_INIT 19 select ARCH_HAS_CURRENT_STACK_POINTER 20 select ARCH_HAS_DEBUG_VM_PGTABLE 21 select ARCH_HAS_FAST_MULTIPLIER 22 select ARCH_HAS_FORTIFY_SOURCE 23 select ARCH_HAS_KCOV 24 select ARCH_HAS_KERNEL_FPU_SUPPORT if CPU_HAS_FPU 25 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 26 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 27 select ARCH_HAS_PREEMPT_LAZY 28 select ARCH_HAS_PTE_SPECIAL 29 select ARCH_HAS_SET_MEMORY 30 select ARCH_HAS_SET_DIRECT_MAP 31 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 32 select ARCH_HAS_UBSAN 33 select ARCH_HAS_VDSO_ARCH_DATA 34 select ARCH_INLINE_READ_LOCK if !PREEMPTION 35 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION 36 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION 37 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION 38 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION 39 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION 40 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION 41 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION 42 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION 43 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION 44 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION 45 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION 46 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION 47 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION 48 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION 49 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION 50 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION 51 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION 52 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION 53 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION 54 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION 55 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION 56 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION 57 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION 58 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION 59 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION 60 select ARCH_KEEP_MEMBLOCK 61 select ARCH_MIGHT_HAVE_PC_PARPORT 62 select ARCH_MIGHT_HAVE_PC_SERIO 63 select ARCH_SPARSEMEM_ENABLE 64 select ARCH_STACKWALK 65 select ARCH_SUPPORTS_ACPI 66 select ARCH_SUPPORTS_ATOMIC_RMW 67 select ARCH_SUPPORTS_HUGETLBFS 68 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 69 select ARCH_SUPPORTS_LTO_CLANG 70 select ARCH_SUPPORTS_LTO_CLANG_THIN 71 select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS 72 select ARCH_SUPPORTS_NUMA_BALANCING 73 select ARCH_SUPPORTS_PER_VMA_LOCK 74 select ARCH_SUPPORTS_RT 75 select ARCH_SUPPORTS_SCHED_SMT if SMP 76 select ARCH_SUPPORTS_SCHED_MC if SMP 77 select ARCH_USE_BUILTIN_BSWAP 78 select ARCH_USE_CMPXCHG_LOCKREF 79 select ARCH_USE_MEMTEST 80 select ARCH_USE_QUEUED_RWLOCKS 81 select ARCH_USE_QUEUED_SPINLOCKS 82 select ARCH_WANT_DEFAULT_BPF_JIT 83 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 84 select ARCH_WANT_LD_ORPHAN_WARN 85 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 86 select ARCH_WANTS_NO_INSTR 87 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 88 select BUILDTIME_TABLE_SORT 89 select COMMON_CLK 90 select CPU_PM 91 select EDAC_SUPPORT 92 select EFI 93 select GENERIC_CLOCKEVENTS 94 select GENERIC_CMOS_UPDATE 95 select GENERIC_CPU_AUTOPROBE 96 select GENERIC_CPU_DEVICES 97 select GENERIC_CPU_VULNERABILITIES 98 select GENERIC_ENTRY 99 select GENERIC_GETTIMEOFDAY 100 select GENERIC_IOREMAP if !ARCH_IOREMAP 101 select GENERIC_IRQ_MATRIX_ALLOCATOR 102 select GENERIC_IRQ_MULTI_HANDLER 103 select GENERIC_IRQ_PROBE 104 select GENERIC_IRQ_SHOW 105 select GENERIC_LIB_ASHLDI3 106 select GENERIC_LIB_ASHRDI3 107 select GENERIC_LIB_CMPDI2 108 select GENERIC_LIB_LSHRDI3 109 select GENERIC_LIB_UCMPDI2 110 select GENERIC_LIB_DEVMEM_IS_ALLOWED 111 select GENERIC_PCI_IOMAP 112 select GENERIC_SCHED_CLOCK 113 select GENERIC_SMP_IDLE_THREAD 114 select GENERIC_TIME_VSYSCALL 115 select GPIOLIB 116 select HAS_IOPORT 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_CONTEXT_TRACKING_USER 134 select HAVE_C_RECORDMCOUNT 135 select HAVE_DEBUG_KMEMLEAK 136 select HAVE_DEBUG_STACKOVERFLOW 137 select HAVE_DMA_CONTIGUOUS 138 select HAVE_DYNAMIC_FTRACE 139 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 140 select HAVE_FTRACE_REGS_HAVING_PT_REGS 141 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 142 select HAVE_DYNAMIC_FTRACE_WITH_REGS 143 select HAVE_EBPF_JIT 144 select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN 145 select HAVE_EXIT_THREAD 146 select HAVE_GENERIC_TIF_BITS 147 select HAVE_GUP_FAST 148 select HAVE_FTRACE_GRAPH_FUNC 149 select HAVE_FUNCTION_ARG_ACCESS_API 150 select HAVE_FUNCTION_ERROR_INJECTION 151 select HAVE_FUNCTION_GRAPH_FREGS 152 select HAVE_FUNCTION_GRAPH_TRACER 153 select HAVE_FUNCTION_TRACER 154 select HAVE_GCC_PLUGINS 155 select HAVE_GENERIC_VDSO 156 select HAVE_HW_BREAKPOINT if PERF_EVENTS 157 select HAVE_IOREMAP_PROT 158 select HAVE_IRQ_EXIT_ON_IRQ_STACK 159 select HAVE_IRQ_TIME_ACCOUNTING 160 select HAVE_KPROBES 161 select HAVE_KPROBES_ON_FTRACE 162 select HAVE_KRETPROBES 163 select HAVE_LIVEPATCH 164 select HAVE_MOD_ARCH_SPECIFIC 165 select HAVE_NMI 166 select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS && AS_HAS_THIN_ADD_SUB 167 select HAVE_PCI 168 select HAVE_PERF_EVENTS 169 select HAVE_PERF_REGS 170 select HAVE_PERF_USER_STACK_DUMP 171 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 172 select HAVE_PREEMPT_DYNAMIC_KEY 173 select HAVE_REGS_AND_STACK_ACCESS_API 174 select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC 175 select HAVE_RETHOOK 176 select HAVE_RSEQ 177 select HAVE_RUST 178 select HAVE_SAMPLE_FTRACE_DIRECT 179 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 180 select HAVE_SETUP_PER_CPU_AREA if NUMA 181 select HAVE_STACK_VALIDATION if HAVE_OBJTOOL 182 select HAVE_STACKPROTECTOR 183 select HAVE_SYSCALL_TRACEPOINTS 184 select HAVE_TIF_NOHZ 185 select HAVE_VIRT_CPU_ACCOUNTING_GEN 186 select IRQ_FORCED_THREADING 187 select IRQ_LOONGARCH_CPU 188 select LOCK_MM_AND_FIND_VMA 189 select MMU_GATHER_MERGE_VMAS if MMU 190 select MMU_GATHER_RCU_TABLE_FREE 191 select MODULES_USE_ELF_RELA if MODULES 192 select NEED_PER_CPU_EMBED_FIRST_CHUNK 193 select NEED_PER_CPU_PAGE_FIRST_CHUNK 194 select NUMA_MEMBLKS if NUMA 195 select OF 196 select OF_EARLY_FLATTREE 197 select PCI 198 select PCI_DOMAINS_GENERIC 199 select PCI_ECAM if ACPI 200 select PCI_LOONGSON 201 select PCI_MSI_ARCH_FALLBACKS 202 select PCI_QUIRKS 203 select PERF_USE_VMALLOC 204 select RTC_LIB 205 select SPARSE_IRQ 206 select SYSCTL_ARCH_UNALIGN_ALLOW 207 select SYSCTL_ARCH_UNALIGN_NO_WARN 208 select SYSCTL_EXCEPTION_TRACE 209 select SWIOTLB 210 select TRACE_IRQFLAGS_SUPPORT 211 select USE_PERCPU_NUMA_NODE_ID 212 select USER_STACKTRACE_SUPPORT 213 select VDSO_GETRANDOM 214 select ZONE_DMA32 215 216config 32BIT 217 bool 218 219config 64BIT 220 def_bool y 221 222config GENERIC_BUG 223 def_bool y 224 depends on BUG 225 226config GENERIC_BUG_RELATIVE_POINTERS 227 def_bool y 228 depends on GENERIC_BUG 229 230config GENERIC_CALIBRATE_DELAY 231 def_bool y 232 233config GENERIC_CSUM 234 def_bool y 235 236config GENERIC_HWEIGHT 237 def_bool y 238 239config L1_CACHE_SHIFT 240 int 241 default "6" 242 243config LOCKDEP_SUPPORT 244 bool 245 default y 246 247config STACKTRACE_SUPPORT 248 bool 249 default y 250 251# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the 252# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that 253# are shared between architectures, and specifically expecting the symbols. 254config MACH_LOONGSON32 255 def_bool 32BIT 256 257config MACH_LOONGSON64 258 def_bool 64BIT 259 260config FIX_EARLYCON_MEM 261 def_bool !ARCH_IOREMAP 262 263config PGTABLE_2LEVEL 264 bool 265 266config PGTABLE_3LEVEL 267 bool 268 269config PGTABLE_4LEVEL 270 bool 271 272config PGTABLE_LEVELS 273 int 274 default 2 if PGTABLE_2LEVEL 275 default 3 if PGTABLE_3LEVEL 276 default 4 if PGTABLE_4LEVEL 277 278config SCHED_OMIT_FRAME_POINTER 279 bool 280 default y 281 282config AS_HAS_EXPLICIT_RELOCS 283 def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x)) 284 285config AS_HAS_FCSR_CLASS 286 def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0) 287 288config AS_HAS_THIN_ADD_SUB 289 def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) || AS_IS_LLVM 290 291config AS_HAS_LSX_EXTENSION 292 def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0) 293 294config AS_HAS_LASX_EXTENSION 295 def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0) 296 297config AS_HAS_LBT_EXTENSION 298 def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0) 299 300config AS_HAS_LVZ_EXTENSION 301 def_bool $(as-instr,hvcl 0) 302 303config CC_HAS_ANNOTATE_TABLEJUMP 304 def_bool $(cc-option,-mannotate-tablejump) 305 306config RUSTC_HAS_ANNOTATE_TABLEJUMP 307 depends on RUST 308 def_bool $(rustc-option,-Cllvm-args=--loongarch-annotate-tablejump) 309 310menu "Kernel type and options" 311 312source "kernel/Kconfig.hz" 313 314choice 315 prompt "Page Table Layout" 316 default 16KB_2LEVEL if 32BIT 317 default 16KB_3LEVEL if 64BIT 318 help 319 Allows choosing the page table layout, which is a combination 320 of page size and page table levels. The size of virtual memory 321 address space are determined by the page table layout. 322 323config 4KB_3LEVEL 324 bool "4KB with 3 levels" 325 select HAVE_PAGE_SIZE_4KB 326 select PGTABLE_3LEVEL 327 help 328 This option selects 4KB page size with 3 level page tables, which 329 support a maximum of 39 bits of application virtual memory. 330 331config 4KB_4LEVEL 332 bool "4KB with 4 levels" 333 select HAVE_PAGE_SIZE_4KB 334 select PGTABLE_4LEVEL 335 help 336 This option selects 4KB page size with 4 level page tables, which 337 support a maximum of 48 bits of application virtual memory. 338 339config 16KB_2LEVEL 340 bool "16KB with 2 levels" 341 select HAVE_PAGE_SIZE_16KB 342 select PGTABLE_2LEVEL 343 help 344 This option selects 16KB page size with 2 level page tables, which 345 support a maximum of 36 bits of application virtual memory. 346 347config 16KB_3LEVEL 348 bool "16KB with 3 levels" 349 select HAVE_PAGE_SIZE_16KB 350 select PGTABLE_3LEVEL 351 help 352 This option selects 16KB page size with 3 level page tables, which 353 support a maximum of 47 bits of application virtual memory. 354 355config 64KB_2LEVEL 356 bool "64KB with 2 levels" 357 select HAVE_PAGE_SIZE_64KB 358 select PGTABLE_2LEVEL 359 help 360 This option selects 64KB page size with 2 level page tables, which 361 support a maximum of 42 bits of application virtual memory. 362 363config 64KB_3LEVEL 364 bool "64KB with 3 levels" 365 select HAVE_PAGE_SIZE_64KB 366 select PGTABLE_3LEVEL 367 help 368 This option selects 64KB page size with 3 level page tables, which 369 support a maximum of 55 bits of application virtual memory. 370 371endchoice 372 373config CMDLINE 374 string "Built-in kernel command line" 375 help 376 For most platforms, the arguments for the kernel's command line 377 are provided at run-time, during boot. However, there are cases 378 where either no arguments are being provided or the provided 379 arguments are insufficient or even invalid. 380 381 When that occurs, it is possible to define a built-in command 382 line here and choose how the kernel should use it later on. 383 384choice 385 prompt "Kernel command line type" 386 default CMDLINE_BOOTLOADER 387 help 388 Choose how the kernel will handle the provided built-in command 389 line. 390 391config CMDLINE_BOOTLOADER 392 bool "Use bootloader kernel arguments if available" 393 help 394 Prefer the command-line passed by the boot loader if available. 395 Use the built-in command line as fallback in case we get nothing 396 during boot. This is the default behaviour. 397 398config CMDLINE_EXTEND 399 bool "Use built-in to extend bootloader kernel arguments" 400 help 401 The built-in command line will be appended to the command- 402 line arguments provided during boot. This is useful in 403 cases where the provided arguments are insufficient and 404 you don't want to or cannot modify them. 405 406config CMDLINE_FORCE 407 bool "Always use the built-in kernel command string" 408 help 409 Always use the built-in command line, even if we get one during 410 boot. This is useful in case you need to override the provided 411 command line on systems where you don't have or want control 412 over it. 413 414endchoice 415 416config BUILTIN_DTB 417 bool "Enable built-in dtb in kernel" 418 depends on OF 419 select GENERIC_BUILTIN_DTB 420 help 421 Some existing systems do not provide a canonical device tree to 422 the kernel at boot time. Let's provide a device tree table in the 423 kernel, keyed by the dts filename, containing the relevant DTBs. 424 425 Built-in DTBs are generic enough and can be used as references. 426 427config BUILTIN_DTB_NAME 428 string "Source file for built-in dtb" 429 depends on BUILTIN_DTB 430 help 431 Base name (without suffix, relative to arch/loongarch/boot/dts/) 432 for the DTS file that will be used to produce the DTB linked into 433 the kernel. 434 435config DMI 436 bool "Enable DMI scanning" 437 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 438 default y 439 help 440 This enables SMBIOS/DMI feature for systems, and scanning of 441 DMI to identify machine quirks. 442 443config EFI 444 bool "EFI runtime service support" 445 select UCS2_STRING 446 select EFI_RUNTIME_WRAPPERS 447 help 448 This enables the kernel to use EFI runtime services that are 449 available (such as the EFI variable services). 450 451config EFI_STUB 452 bool "EFI boot stub support" 453 default y 454 depends on EFI 455 select EFI_GENERIC_STUB 456 help 457 This kernel feature allows the kernel to be loaded directly by 458 EFI firmware without the use of a bootloader. 459 460config SMP 461 bool "Multi-Processing support" 462 help 463 This enables support for systems with more than one CPU. If you have 464 a system with only one CPU, say N. If you have a system with more 465 than one CPU, say Y. 466 467 If you say N here, the kernel will run on uni- and multiprocessor 468 machines, but will use only one CPU of a multiprocessor machine. If 469 you say Y here, the kernel will run on many, but not all, 470 uniprocessor machines. On a uniprocessor machine, the kernel 471 will run faster if you say N here. 472 473 See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. 474 475 If you don't know what to do here, say N. 476 477config HOTPLUG_CPU 478 bool "Support for hot-pluggable CPUs" 479 depends on SMP 480 select GENERIC_IRQ_MIGRATION 481 help 482 Say Y here to allow turning CPUs off and on. CPUs can be 483 controlled through /sys/devices/system/cpu. 484 (Note: power management support will enable this option 485 automatically on SMP systems. ) 486 Say N if you want to disable CPU hotplug. 487 488config NR_CPUS 489 int "Maximum number of CPUs (2-2048)" 490 range 2 2048 491 default "2048" 492 depends on SMP 493 help 494 This allows you to specify the maximum number of CPUs which this 495 kernel will support. 496 497config NUMA 498 bool "NUMA Support" 499 select SMP 500 help 501 Say Y to compile the kernel with NUMA (Non-Uniform Memory Access) 502 support. This option improves performance on systems with more 503 than one NUMA node; on single node systems it is generally better 504 to leave it disabled. 505 506config NODES_SHIFT 507 int 508 default "6" 509 depends on NUMA 510 511config ARCH_FORCE_MAX_ORDER 512 int "Maximum zone order" 513 default "13" if PAGE_SIZE_64KB 514 default "11" if PAGE_SIZE_16KB 515 default "10" 516 help 517 The kernel memory allocator divides physically contiguous memory 518 blocks into "zones", where each zone is a power of two number of 519 pages. This option selects the largest power of two that the kernel 520 keeps in the memory allocator. If you need to allocate very large 521 blocks of physically contiguous memory, then you may need to 522 increase this value. 523 524 The page size is not necessarily 4KB. Keep this in mind 525 when choosing a value for this option. 526 527config ARCH_IOREMAP 528 bool "Enable LoongArch DMW-based ioremap()" 529 help 530 We use generic TLB-based ioremap() by default since it has page 531 protection support. However, you can enable LoongArch DMW-based 532 ioremap() for better performance. 533 534config ARCH_WRITECOMBINE 535 bool "Enable WriteCombine (WUC) for ioremap()" 536 help 537 LoongArch maintains cache coherency in hardware, but when paired 538 with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which 539 is similar to WriteCombine) is out of the scope of cache coherency 540 machanism for PCIe devices (this is a PCIe protocol violation, which 541 may be fixed in newer chipsets). 542 543 This means WUC can only used for write-only memory regions now, so 544 this option is disabled by default, making WUC silently fallback to 545 SUC for ioremap(). You can enable this option if the kernel is ensured 546 to run on hardware without this bug. 547 548 You can override this setting via writecombine=on/off boot parameter. 549 550config ARCH_STRICT_ALIGN 551 bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT 552 default y 553 help 554 Not all LoongArch cores support h/w unaligned access, we can use 555 -mstrict-align build parameter to prevent unaligned accesses. 556 557 CPUs with h/w unaligned access support: 558 Loongson-2K2000/2K3000 and all of Loongson-3 series processors 559 based on LoongArch. 560 561 CPUs without h/w unaligned access support: 562 Loongson-2K0300/2K0500/2K1000. 563 564 If you want to make sure whether to support unaligned memory access 565 on your hardware, please read the bit 20 (UAL) of CPUCFG1 register. 566 567 This option is enabled by default to make the kernel be able to run 568 on all LoongArch systems. But you can disable it manually if you want 569 to run kernel only on systems with h/w unaligned access support in 570 order to optimise for performance. 571 572config CPU_HAS_AMO 573 bool 574 default 64BIT 575 576config CPU_HAS_FPU 577 bool 578 default y 579 580config CPU_HAS_LSX 581 bool "Support for the Loongson SIMD Extension" 582 depends on AS_HAS_LSX_EXTENSION 583 help 584 Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers 585 and a set of SIMD instructions to operate on them. When this option 586 is enabled the kernel will support allocating & switching LSX 587 vector register contexts. If you know that your kernel will only be 588 running on CPUs which do not support LSX or that your userland will 589 not be making use of it then you may wish to say N here to reduce 590 the size & complexity of your kernel. 591 592 If unsure, say Y. 593 594config CPU_HAS_LASX 595 bool "Support for the Loongson Advanced SIMD Extension" 596 depends on CPU_HAS_LSX 597 depends on AS_HAS_LASX_EXTENSION 598 help 599 Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector 600 registers and a set of SIMD instructions to operate on them. When this 601 option is enabled the kernel will support allocating & switching LASX 602 vector register contexts. If you know that your kernel will only be 603 running on CPUs which do not support LASX or that your userland will 604 not be making use of it then you may wish to say N here to reduce 605 the size & complexity of your kernel. 606 607 If unsure, say Y. 608 609config CPU_HAS_LBT 610 bool "Support for the Loongson Binary Translation Extension" 611 depends on AS_HAS_LBT_EXTENSION 612 help 613 Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0 614 to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). 615 Enabling this option allows the kernel to allocate and switch registers 616 specific to LBT. 617 618 If you want to use this feature, such as the Loongson Architecture 619 Translator (LAT), say Y. 620 621config CPU_HAS_PREFETCH 622 bool 623 default y 624 625config ARCH_SUPPORTS_KEXEC 626 def_bool y 627 628config ARCH_SUPPORTS_KEXEC_FILE 629 def_bool 64BIT 630 631config ARCH_SELECTS_KEXEC_FILE 632 def_bool 64BIT 633 depends on KEXEC_FILE 634 select KEXEC_ELF 635 select RELOCATABLE 636 select HAVE_IMA_KEXEC if IMA 637 638config ARCH_SUPPORTS_CRASH_DUMP 639 def_bool y 640 641config ARCH_DEFAULT_CRASH_DUMP 642 def_bool y 643 644config ARCH_SELECTS_CRASH_DUMP 645 def_bool y 646 depends on CRASH_DUMP 647 select RELOCATABLE 648 649config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 650 def_bool CRASH_RESERVE 651 652config RELOCATABLE 653 bool "Relocatable kernel" 654 select ARCH_HAS_RELR 655 help 656 This builds the kernel as a Position Independent Executable (PIE), 657 which retains all relocation metadata required, so as to relocate 658 the kernel binary at runtime to a different virtual address from 659 its link address. 660 661config RANDOMIZE_BASE 662 bool "Randomize the address of the kernel (KASLR)" 663 depends on RELOCATABLE 664 help 665 Randomizes the physical and virtual address at which the 666 kernel image is loaded, as a security feature that 667 deters exploit attempts relying on knowledge of the location 668 of kernel internals. 669 670 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET. 671 672 If unsure, say N. 673 674config RANDOMIZE_BASE_MAX_OFFSET 675 hex "Maximum KASLR offset" if EXPERT 676 depends on RANDOMIZE_BASE 677 range 0x0 0x10000000 678 default "0x01000000" 679 help 680 When KASLR is active, this provides the maximum offset that will 681 be applied to the kernel image. It should be set according to the 682 amount of physical RAM available in the target system. 683 684 This is limited by the size of the lower address memory, 256MB. 685 686source "kernel/livepatch/Kconfig" 687 688config PARAVIRT 689 bool "Enable paravirtualization code" 690 depends on AS_HAS_LVZ_EXTENSION 691 select HAVE_PV_STEAL_CLOCK_GEN 692 help 693 This changes the kernel so it can modify itself when it is run 694 under a hypervisor, potentially improving performance significantly 695 over full virtualization. However, when run without a hypervisor 696 the kernel is theoretically slower and slightly larger. 697 698config PARAVIRT_TIME_ACCOUNTING 699 bool "Paravirtual steal time accounting" 700 depends on PARAVIRT 701 help 702 Select this option to enable fine granularity task steal time 703 accounting. Time spent executing other tasks in parallel with 704 the current vCPU is discounted from the vCPU power. To account for 705 that, there can be a small performance impact. 706 707 If in doubt, say N here. 708 709endmenu 710 711config ARCH_SELECT_MEMORY_MODEL 712 def_bool y 713 714config ARCH_FLATMEM_ENABLE 715 def_bool y 716 depends on !NUMA 717 718config ARCH_SPARSEMEM_ENABLE 719 def_bool y 720 select SPARSEMEM_VMEMMAP_ENABLE 721 help 722 Say Y to support efficient handling of sparse physical memory, 723 for architectures which are either NUMA (Non-Uniform Memory Access) 724 or have huge holes in the physical address space for other reasons. 725 See <file:Documentation/mm/numa.rst> for more. 726 727config ARCH_MEMORY_PROBE 728 def_bool y 729 depends on MEMORY_HOTPLUG 730 731config MMU 732 bool 733 default y 734 735config ARCH_MMAP_RND_BITS_MIN 736 default 12 737 738config ARCH_MMAP_RND_BITS_MAX 739 default 18 740 741config ARCH_SUPPORTS_UPROBES 742 def_bool y 743 744config KASAN_SHADOW_OFFSET 745 hex 746 default 0x0 747 depends on KASAN 748 749menu "Power management options" 750 751config ARCH_SUSPEND_POSSIBLE 752 def_bool y 753 754config ARCH_HIBERNATION_POSSIBLE 755 def_bool y 756 757source "kernel/power/Kconfig" 758source "drivers/acpi/Kconfig" 759source "drivers/cpufreq/Kconfig" 760 761endmenu 762 763source "arch/loongarch/kvm/Kconfig" 764