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_CRC32 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_DEVMAP 29 select ARCH_HAS_PTE_SPECIAL 30 select ARCH_HAS_SET_MEMORY 31 select ARCH_HAS_SET_DIRECT_MAP 32 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 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_NUMA_BALANCING 72 select ARCH_SUPPORTS_RT 73 select ARCH_USE_BUILTIN_BSWAP 74 select ARCH_USE_CMPXCHG_LOCKREF 75 select ARCH_USE_QUEUED_RWLOCKS 76 select ARCH_USE_QUEUED_SPINLOCKS 77 select ARCH_WANT_DEFAULT_BPF_JIT 78 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 79 select ARCH_WANT_LD_ORPHAN_WARN 80 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 81 select ARCH_WANTS_NO_INSTR 82 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 83 select BUILDTIME_TABLE_SORT 84 select COMMON_CLK 85 select CPU_PM 86 select EDAC_SUPPORT 87 select EFI 88 select GENERIC_CLOCKEVENTS 89 select GENERIC_CMOS_UPDATE 90 select GENERIC_CPU_AUTOPROBE 91 select GENERIC_CPU_DEVICES 92 select GENERIC_CPU_VULNERABILITIES 93 select GENERIC_ENTRY 94 select GENERIC_GETTIMEOFDAY 95 select GENERIC_IOREMAP if !ARCH_IOREMAP 96 select GENERIC_IRQ_MATRIX_ALLOCATOR 97 select GENERIC_IRQ_MULTI_HANDLER 98 select GENERIC_IRQ_PROBE 99 select GENERIC_IRQ_SHOW 100 select GENERIC_LIB_ASHLDI3 101 select GENERIC_LIB_ASHRDI3 102 select GENERIC_LIB_CMPDI2 103 select GENERIC_LIB_LSHRDI3 104 select GENERIC_LIB_UCMPDI2 105 select GENERIC_LIB_DEVMEM_IS_ALLOWED 106 select GENERIC_PCI_IOMAP 107 select GENERIC_SCHED_CLOCK 108 select GENERIC_SMP_IDLE_THREAD 109 select GENERIC_TIME_VSYSCALL 110 select GENERIC_VDSO_DATA_STORE 111 select GENERIC_VDSO_TIME_NS 112 select GPIOLIB 113 select HAS_IOPORT 114 select HAVE_ARCH_AUDITSYSCALL 115 select HAVE_ARCH_JUMP_LABEL 116 select HAVE_ARCH_JUMP_LABEL_RELATIVE 117 select HAVE_ARCH_KASAN 118 select HAVE_ARCH_KFENCE 119 select HAVE_ARCH_KGDB if PERF_EVENTS 120 select HAVE_ARCH_MMAP_RND_BITS if MMU 121 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 122 select HAVE_ARCH_SECCOMP 123 select HAVE_ARCH_SECCOMP_FILTER 124 select HAVE_ARCH_TRACEHOOK 125 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 126 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD 127 select HAVE_ASM_MODVERSIONS 128 select HAVE_CONTEXT_TRACKING_USER 129 select HAVE_C_RECORDMCOUNT 130 select HAVE_DEBUG_KMEMLEAK 131 select HAVE_DEBUG_STACKOVERFLOW 132 select HAVE_DMA_CONTIGUOUS 133 select HAVE_DYNAMIC_FTRACE 134 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 135 select HAVE_FTRACE_REGS_HAVING_PT_REGS 136 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 137 select HAVE_DYNAMIC_FTRACE_WITH_REGS 138 select HAVE_EBPF_JIT 139 select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN 140 select HAVE_EXIT_THREAD 141 select HAVE_GUP_FAST 142 select HAVE_FTRACE_GRAPH_FUNC 143 select HAVE_FTRACE_MCOUNT_RECORD 144 select HAVE_FUNCTION_ARG_ACCESS_API 145 select HAVE_FUNCTION_ERROR_INJECTION 146 select HAVE_FUNCTION_GRAPH_FREGS 147 select HAVE_FUNCTION_GRAPH_TRACER 148 select HAVE_FUNCTION_TRACER 149 select HAVE_GCC_PLUGINS 150 select HAVE_GENERIC_VDSO 151 select HAVE_HW_BREAKPOINT if PERF_EVENTS 152 select HAVE_IOREMAP_PROT 153 select HAVE_IRQ_EXIT_ON_IRQ_STACK 154 select HAVE_IRQ_TIME_ACCOUNTING 155 select HAVE_KPROBES 156 select HAVE_KPROBES_ON_FTRACE 157 select HAVE_KRETPROBES 158 select HAVE_LIVEPATCH 159 select HAVE_MOD_ARCH_SPECIFIC 160 select HAVE_NMI 161 select HAVE_OBJTOOL if AS_HAS_EXPLICIT_RELOCS && AS_HAS_THIN_ADD_SUB 162 select HAVE_PCI 163 select HAVE_PERF_EVENTS 164 select HAVE_PERF_REGS 165 select HAVE_PERF_USER_STACK_DUMP 166 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 167 select HAVE_PREEMPT_DYNAMIC_KEY 168 select HAVE_REGS_AND_STACK_ACCESS_API 169 select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC 170 select HAVE_RETHOOK 171 select HAVE_RSEQ 172 select HAVE_RUST 173 select HAVE_SAMPLE_FTRACE_DIRECT 174 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 175 select HAVE_SETUP_PER_CPU_AREA if NUMA 176 select HAVE_STACK_VALIDATION if HAVE_OBJTOOL 177 select HAVE_STACKPROTECTOR 178 select HAVE_SYSCALL_TRACEPOINTS 179 select HAVE_TIF_NOHZ 180 select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP 181 select IRQ_FORCED_THREADING 182 select IRQ_LOONGARCH_CPU 183 select LOCK_MM_AND_FIND_VMA 184 select MMU_GATHER_MERGE_VMAS if MMU 185 select MODULES_USE_ELF_RELA if MODULES 186 select NEED_PER_CPU_EMBED_FIRST_CHUNK 187 select NEED_PER_CPU_PAGE_FIRST_CHUNK 188 select OF 189 select OF_EARLY_FLATTREE 190 select PCI 191 select PCI_DOMAINS_GENERIC 192 select PCI_ECAM if ACPI 193 select PCI_LOONGSON 194 select PCI_MSI_ARCH_FALLBACKS 195 select PCI_QUIRKS 196 select PERF_USE_VMALLOC 197 select RTC_LIB 198 select SPARSE_IRQ 199 select SYSCTL_ARCH_UNALIGN_ALLOW 200 select SYSCTL_ARCH_UNALIGN_NO_WARN 201 select SYSCTL_EXCEPTION_TRACE 202 select SWIOTLB 203 select TRACE_IRQFLAGS_SUPPORT 204 select USE_PERCPU_NUMA_NODE_ID 205 select USER_STACKTRACE_SUPPORT 206 select VDSO_GETRANDOM 207 select ZONE_DMA32 208 209config 32BIT 210 bool 211 212config 64BIT 213 def_bool y 214 215config GENERIC_BUG 216 def_bool y 217 depends on BUG 218 219config GENERIC_BUG_RELATIVE_POINTERS 220 def_bool y 221 depends on GENERIC_BUG 222 223config GENERIC_CALIBRATE_DELAY 224 def_bool y 225 226config GENERIC_CSUM 227 def_bool y 228 229config GENERIC_HWEIGHT 230 def_bool y 231 232config L1_CACHE_SHIFT 233 int 234 default "6" 235 236config LOCKDEP_SUPPORT 237 bool 238 default y 239 240config STACKTRACE_SUPPORT 241 bool 242 default y 243 244# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the 245# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that 246# are shared between architectures, and specifically expecting the symbols. 247config MACH_LOONGSON32 248 def_bool 32BIT 249 250config MACH_LOONGSON64 251 def_bool 64BIT 252 253config FIX_EARLYCON_MEM 254 def_bool !ARCH_IOREMAP 255 256config PGTABLE_2LEVEL 257 bool 258 259config PGTABLE_3LEVEL 260 bool 261 262config PGTABLE_4LEVEL 263 bool 264 265config PGTABLE_LEVELS 266 int 267 default 2 if PGTABLE_2LEVEL 268 default 3 if PGTABLE_3LEVEL 269 default 4 if PGTABLE_4LEVEL 270 271config SCHED_OMIT_FRAME_POINTER 272 bool 273 default y 274 275config AS_HAS_EXPLICIT_RELOCS 276 def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x)) 277 278config AS_HAS_FCSR_CLASS 279 def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0) 280 281config AS_HAS_THIN_ADD_SUB 282 def_bool $(cc-option,-Wa$(comma)-mthin-add-sub) || AS_IS_LLVM 283 284config AS_HAS_LSX_EXTENSION 285 def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0) 286 287config AS_HAS_LASX_EXTENSION 288 def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0) 289 290config AS_HAS_LBT_EXTENSION 291 def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0) 292 293config AS_HAS_LVZ_EXTENSION 294 def_bool $(as-instr,hvcl 0) 295 296config CC_HAS_ANNOTATE_TABLEJUMP 297 def_bool $(cc-option,-mannotate-tablejump) 298 299menu "Kernel type and options" 300 301source "kernel/Kconfig.hz" 302 303choice 304 prompt "Page Table Layout" 305 default 16KB_2LEVEL if 32BIT 306 default 16KB_3LEVEL if 64BIT 307 help 308 Allows choosing the page table layout, which is a combination 309 of page size and page table levels. The size of virtual memory 310 address space are determined by the page table layout. 311 312config 4KB_3LEVEL 313 bool "4KB with 3 levels" 314 select HAVE_PAGE_SIZE_4KB 315 select PGTABLE_3LEVEL 316 help 317 This option selects 4KB page size with 3 level page tables, which 318 support a maximum of 39 bits of application virtual memory. 319 320config 4KB_4LEVEL 321 bool "4KB with 4 levels" 322 select HAVE_PAGE_SIZE_4KB 323 select PGTABLE_4LEVEL 324 help 325 This option selects 4KB page size with 4 level page tables, which 326 support a maximum of 48 bits of application virtual memory. 327 328config 16KB_2LEVEL 329 bool "16KB with 2 levels" 330 select HAVE_PAGE_SIZE_16KB 331 select PGTABLE_2LEVEL 332 help 333 This option selects 16KB page size with 2 level page tables, which 334 support a maximum of 36 bits of application virtual memory. 335 336config 16KB_3LEVEL 337 bool "16KB with 3 levels" 338 select HAVE_PAGE_SIZE_16KB 339 select PGTABLE_3LEVEL 340 help 341 This option selects 16KB page size with 3 level page tables, which 342 support a maximum of 47 bits of application virtual memory. 343 344config 64KB_2LEVEL 345 bool "64KB with 2 levels" 346 select HAVE_PAGE_SIZE_64KB 347 select PGTABLE_2LEVEL 348 help 349 This option selects 64KB page size with 2 level page tables, which 350 support a maximum of 42 bits of application virtual memory. 351 352config 64KB_3LEVEL 353 bool "64KB with 3 levels" 354 select HAVE_PAGE_SIZE_64KB 355 select PGTABLE_3LEVEL 356 help 357 This option selects 64KB page size with 3 level page tables, which 358 support a maximum of 55 bits of application virtual memory. 359 360endchoice 361 362config CMDLINE 363 string "Built-in kernel command line" 364 help 365 For most platforms, the arguments for the kernel's command line 366 are provided at run-time, during boot. However, there are cases 367 where either no arguments are being provided or the provided 368 arguments are insufficient or even invalid. 369 370 When that occurs, it is possible to define a built-in command 371 line here and choose how the kernel should use it later on. 372 373choice 374 prompt "Kernel command line type" 375 default CMDLINE_BOOTLOADER 376 help 377 Choose how the kernel will handle the provided built-in command 378 line. 379 380config CMDLINE_BOOTLOADER 381 bool "Use bootloader kernel arguments if available" 382 help 383 Prefer the command-line passed by the boot loader if available. 384 Use the built-in command line as fallback in case we get nothing 385 during boot. This is the default behaviour. 386 387config CMDLINE_EXTEND 388 bool "Use built-in to extend bootloader kernel arguments" 389 help 390 The command-line arguments provided during boot will be 391 appended to the built-in command line. This is useful in 392 cases where the provided arguments are insufficient and 393 you don't want to or cannot modify them. 394 395config CMDLINE_FORCE 396 bool "Always use the built-in kernel command string" 397 help 398 Always use the built-in command line, even if we get one during 399 boot. This is useful in case you need to override the provided 400 command line on systems where you don't have or want control 401 over it. 402 403endchoice 404 405config BUILTIN_DTB 406 bool "Enable built-in dtb in kernel" 407 depends on OF 408 select GENERIC_BUILTIN_DTB 409 help 410 Some existing systems do not provide a canonical device tree to 411 the kernel at boot time. Let's provide a device tree table in the 412 kernel, keyed by the dts filename, containing the relevant DTBs. 413 414 Built-in DTBs are generic enough and can be used as references. 415 416config BUILTIN_DTB_NAME 417 string "Source file for built-in dtb" 418 depends on BUILTIN_DTB 419 help 420 Base name (without suffix, relative to arch/loongarch/boot/dts/) 421 for the DTS file that will be used to produce the DTB linked into 422 the kernel. 423 424config DMI 425 bool "Enable DMI scanning" 426 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 427 default y 428 help 429 This enables SMBIOS/DMI feature for systems, and scanning of 430 DMI to identify machine quirks. 431 432config EFI 433 bool "EFI runtime service support" 434 select UCS2_STRING 435 select EFI_RUNTIME_WRAPPERS 436 help 437 This enables the kernel to use EFI runtime services that are 438 available (such as the EFI variable services). 439 440config EFI_STUB 441 bool "EFI boot stub support" 442 default y 443 depends on EFI 444 select EFI_GENERIC_STUB 445 help 446 This kernel feature allows the kernel to be loaded directly by 447 EFI firmware without the use of a bootloader. 448 449config SCHED_SMT 450 bool "SMT scheduler support" 451 depends on SMP 452 default y 453 help 454 Improves scheduler's performance when there are multiple 455 threads in one physical core. 456 457config SMP 458 bool "Multi-Processing support" 459 help 460 This enables support for systems with more than one CPU. If you have 461 a system with only one CPU, say N. If you have a system with more 462 than one CPU, say Y. 463 464 If you say N here, the kernel will run on uni- and multiprocessor 465 machines, but will use only one CPU of a multiprocessor machine. If 466 you say Y here, the kernel will run on many, but not all, 467 uniprocessor machines. On a uniprocessor machine, the kernel 468 will run faster if you say N here. 469 470 See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. 471 472 If you don't know what to do here, say N. 473 474config HOTPLUG_CPU 475 bool "Support for hot-pluggable CPUs" 476 depends on SMP 477 select GENERIC_IRQ_MIGRATION 478 help 479 Say Y here to allow turning CPUs off and on. CPUs can be 480 controlled through /sys/devices/system/cpu. 481 (Note: power management support will enable this option 482 automatically on SMP systems. ) 483 Say N if you want to disable CPU hotplug. 484 485config NR_CPUS 486 int "Maximum number of CPUs (2-256)" 487 range 2 256 488 depends on SMP 489 default "64" 490 help 491 This allows you to specify the maximum number of CPUs which this 492 kernel will support. 493 494config NUMA 495 bool "NUMA Support" 496 select SMP 497 help 498 Say Y to compile the kernel with NUMA (Non-Uniform Memory Access) 499 support. This option improves performance on systems with more 500 than one NUMA node; on single node systems it is generally better 501 to leave it disabled. 502 503config NODES_SHIFT 504 int 505 default "6" 506 depends on NUMA 507 508config ARCH_FORCE_MAX_ORDER 509 int "Maximum zone order" 510 default "13" if PAGE_SIZE_64KB 511 default "11" if PAGE_SIZE_16KB 512 default "10" 513 help 514 The kernel memory allocator divides physically contiguous memory 515 blocks into "zones", where each zone is a power of two number of 516 pages. This option selects the largest power of two that the kernel 517 keeps in the memory allocator. If you need to allocate very large 518 blocks of physically contiguous memory, then you may need to 519 increase this value. 520 521 The page size is not necessarily 4KB. Keep this in mind 522 when choosing a value for this option. 523 524config ARCH_IOREMAP 525 bool "Enable LoongArch DMW-based ioremap()" 526 help 527 We use generic TLB-based ioremap() by default since it has page 528 protection support. However, you can enable LoongArch DMW-based 529 ioremap() for better performance. 530 531config ARCH_WRITECOMBINE 532 bool "Enable WriteCombine (WUC) for ioremap()" 533 help 534 LoongArch maintains cache coherency in hardware, but when paired 535 with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which 536 is similar to WriteCombine) is out of the scope of cache coherency 537 machanism for PCIe devices (this is a PCIe protocol violation, which 538 may be fixed in newer chipsets). 539 540 This means WUC can only used for write-only memory regions now, so 541 this option is disabled by default, making WUC silently fallback to 542 SUC for ioremap(). You can enable this option if the kernel is ensured 543 to run on hardware without this bug. 544 545 You can override this setting via writecombine=on/off boot parameter. 546 547config ARCH_STRICT_ALIGN 548 bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT 549 default y 550 help 551 Not all LoongArch cores support h/w unaligned access, we can use 552 -mstrict-align build parameter to prevent unaligned accesses. 553 554 CPUs with h/w unaligned access support: 555 Loongson-2K2000/2K3000/3A5000/3C5000/3D5000. 556 557 CPUs without h/w unaligned access support: 558 Loongson-2K500/2K1000. 559 560 This option is enabled by default to make the kernel be able to run 561 on all LoongArch systems. But you can disable it manually if you want 562 to run kernel only on systems with h/w unaligned access support in 563 order to optimise for performance. 564 565config CPU_HAS_FPU 566 bool 567 default y 568 569config CPU_HAS_LSX 570 bool "Support for the Loongson SIMD Extension" 571 depends on AS_HAS_LSX_EXTENSION 572 help 573 Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers 574 and a set of SIMD instructions to operate on them. When this option 575 is enabled the kernel will support allocating & switching LSX 576 vector register contexts. If you know that your kernel will only be 577 running on CPUs which do not support LSX or that your userland will 578 not be making use of it then you may wish to say N here to reduce 579 the size & complexity of your kernel. 580 581 If unsure, say Y. 582 583config CPU_HAS_LASX 584 bool "Support for the Loongson Advanced SIMD Extension" 585 depends on CPU_HAS_LSX 586 depends on AS_HAS_LASX_EXTENSION 587 help 588 Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector 589 registers and a set of SIMD instructions to operate on them. When this 590 option is enabled the kernel will support allocating & switching LASX 591 vector register contexts. If you know that your kernel will only be 592 running on CPUs which do not support LASX or that your userland will 593 not be making use of it then you may wish to say N here to reduce 594 the size & complexity of your kernel. 595 596 If unsure, say Y. 597 598config CPU_HAS_LBT 599 bool "Support for the Loongson Binary Translation Extension" 600 depends on AS_HAS_LBT_EXTENSION 601 help 602 Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0 603 to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). 604 Enabling this option allows the kernel to allocate and switch registers 605 specific to LBT. 606 607 If you want to use this feature, such as the Loongson Architecture 608 Translator (LAT), say Y. 609 610config CPU_HAS_PREFETCH 611 bool 612 default y 613 614config ARCH_SUPPORTS_KEXEC 615 def_bool y 616 617config ARCH_SUPPORTS_CRASH_DUMP 618 def_bool y 619 620config ARCH_DEFAULT_CRASH_DUMP 621 def_bool y 622 623config ARCH_SELECTS_CRASH_DUMP 624 def_bool y 625 depends on CRASH_DUMP 626 select RELOCATABLE 627 628config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 629 def_bool CRASH_RESERVE 630 631config RELOCATABLE 632 bool "Relocatable kernel" 633 select ARCH_HAS_RELR 634 help 635 This builds the kernel as a Position Independent Executable (PIE), 636 which retains all relocation metadata required, so as to relocate 637 the kernel binary at runtime to a different virtual address from 638 its link address. 639 640config RANDOMIZE_BASE 641 bool "Randomize the address of the kernel (KASLR)" 642 depends on RELOCATABLE 643 help 644 Randomizes the physical and virtual address at which the 645 kernel image is loaded, as a security feature that 646 deters exploit attempts relying on knowledge of the location 647 of kernel internals. 648 649 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET. 650 651 If unsure, say N. 652 653config RANDOMIZE_BASE_MAX_OFFSET 654 hex "Maximum KASLR offset" if EXPERT 655 depends on RANDOMIZE_BASE 656 range 0x0 0x10000000 657 default "0x01000000" 658 help 659 When KASLR is active, this provides the maximum offset that will 660 be applied to the kernel image. It should be set according to the 661 amount of physical RAM available in the target system. 662 663 This is limited by the size of the lower address memory, 256MB. 664 665source "kernel/livepatch/Kconfig" 666 667config PARAVIRT 668 bool "Enable paravirtualization code" 669 depends on AS_HAS_LVZ_EXTENSION 670 help 671 This changes the kernel so it can modify itself when it is run 672 under a hypervisor, potentially improving performance significantly 673 over full virtualization. However, when run without a hypervisor 674 the kernel is theoretically slower and slightly larger. 675 676config PARAVIRT_TIME_ACCOUNTING 677 bool "Paravirtual steal time accounting" 678 depends on PARAVIRT 679 help 680 Select this option to enable fine granularity task steal time 681 accounting. Time spent executing other tasks in parallel with 682 the current vCPU is discounted from the vCPU power. To account for 683 that, there can be a small performance impact. 684 685 If in doubt, say N here. 686 687endmenu 688 689config ARCH_SELECT_MEMORY_MODEL 690 def_bool y 691 692config ARCH_FLATMEM_ENABLE 693 def_bool y 694 depends on !NUMA 695 696config ARCH_SPARSEMEM_ENABLE 697 def_bool y 698 select SPARSEMEM_VMEMMAP_ENABLE 699 help 700 Say Y to support efficient handling of sparse physical memory, 701 for architectures which are either NUMA (Non-Uniform Memory Access) 702 or have huge holes in the physical address space for other reasons. 703 See <file:Documentation/mm/numa.rst> for more. 704 705config ARCH_MEMORY_PROBE 706 def_bool y 707 depends on MEMORY_HOTPLUG 708 709config MMU 710 bool 711 default y 712 713config ARCH_MMAP_RND_BITS_MIN 714 default 12 715 716config ARCH_MMAP_RND_BITS_MAX 717 default 18 718 719config ARCH_SUPPORTS_UPROBES 720 def_bool y 721 722config KASAN_SHADOW_OFFSET 723 hex 724 default 0x0 725 depends on KASAN 726 727menu "Power management options" 728 729config ARCH_SUSPEND_POSSIBLE 730 def_bool y 731 732config ARCH_HIBERNATION_POSSIBLE 733 def_bool y 734 735source "kernel/power/Kconfig" 736source "drivers/acpi/Kconfig" 737source "drivers/cpufreq/Kconfig" 738 739endmenu 740 741source "arch/loongarch/kvm/Kconfig" 742