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