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 AS_HAS_SCQ_EXTENSION 308 def_bool $(as-instr,sc.q \$t0$(comma)\$t1$(comma)\$t2) 309 310config CC_HAS_ANNOTATE_TABLEJUMP 311 def_bool $(cc-option,-mannotate-tablejump) 312 313config RUSTC_HAS_ANNOTATE_TABLEJUMP 314 depends on RUST 315 def_bool $(rustc-option,-Cllvm-args=--loongarch-annotate-tablejump) 316 317menu "Kernel type and options" 318 319source "kernel/Kconfig.hz" 320 321choice 322 prompt "Page Table Layout" 323 default 16KB_2LEVEL if 32BIT 324 default 16KB_3LEVEL if 64BIT 325 help 326 Allows choosing the page table layout, which is a combination 327 of page size and page table levels. The size of virtual memory 328 address space are determined by the page table layout. 329 330config 4KB_3LEVEL 331 bool "4KB with 3 levels" 332 select HAVE_PAGE_SIZE_4KB 333 select PGTABLE_3LEVEL 334 help 335 This option selects 4KB page size with 3 level page tables, which 336 support a maximum of 39 bits of application virtual memory. 337 338config 4KB_4LEVEL 339 bool "4KB with 4 levels" 340 select HAVE_PAGE_SIZE_4KB 341 select PGTABLE_4LEVEL 342 help 343 This option selects 4KB page size with 4 level page tables, which 344 support a maximum of 48 bits of application virtual memory. 345 346config 16KB_2LEVEL 347 bool "16KB with 2 levels" 348 select HAVE_PAGE_SIZE_16KB 349 select PGTABLE_2LEVEL 350 help 351 This option selects 16KB page size with 2 level page tables, which 352 support a maximum of 36 bits of application virtual memory. 353 354config 16KB_3LEVEL 355 bool "16KB with 3 levels" 356 select HAVE_PAGE_SIZE_16KB 357 select PGTABLE_3LEVEL 358 help 359 This option selects 16KB page size with 3 level page tables, which 360 support a maximum of 47 bits of application virtual memory. 361 362config 64KB_2LEVEL 363 bool "64KB with 2 levels" 364 select HAVE_PAGE_SIZE_64KB 365 select PGTABLE_2LEVEL 366 help 367 This option selects 64KB page size with 2 level page tables, which 368 support a maximum of 42 bits of application virtual memory. 369 370config 64KB_3LEVEL 371 bool "64KB with 3 levels" 372 select HAVE_PAGE_SIZE_64KB 373 select PGTABLE_3LEVEL 374 help 375 This option selects 64KB page size with 3 level page tables, which 376 support a maximum of 55 bits of application virtual memory. 377 378endchoice 379 380config CMDLINE 381 string "Built-in kernel command line" 382 help 383 For most platforms, the arguments for the kernel's command line 384 are provided at run-time, during boot. However, there are cases 385 where either no arguments are being provided or the provided 386 arguments are insufficient or even invalid. 387 388 When that occurs, it is possible to define a built-in command 389 line here and choose how the kernel should use it later on. 390 391choice 392 prompt "Kernel command line type" 393 default CMDLINE_BOOTLOADER 394 help 395 Choose how the kernel will handle the provided built-in command 396 line. 397 398config CMDLINE_BOOTLOADER 399 bool "Use bootloader kernel arguments if available" 400 help 401 Prefer the command-line passed by the boot loader if available. 402 Use the built-in command line as fallback in case we get nothing 403 during boot. This is the default behaviour. 404 405config CMDLINE_EXTEND 406 bool "Use built-in to extend bootloader kernel arguments" 407 help 408 The built-in command line will be appended to the command- 409 line arguments provided during boot. This is useful in 410 cases where the provided arguments are insufficient and 411 you don't want to or cannot modify them. 412 413config CMDLINE_FORCE 414 bool "Always use the built-in kernel command string" 415 help 416 Always use the built-in command line, even if we get one during 417 boot. This is useful in case you need to override the provided 418 command line on systems where you don't have or want control 419 over it. 420 421endchoice 422 423config BUILTIN_DTB 424 bool "Enable built-in dtb in kernel" 425 depends on OF 426 select GENERIC_BUILTIN_DTB 427 help 428 Some existing systems do not provide a canonical device tree to 429 the kernel at boot time. Let's provide a device tree table in the 430 kernel, keyed by the dts filename, containing the relevant DTBs. 431 432 Built-in DTBs are generic enough and can be used as references. 433 434config BUILTIN_DTB_NAME 435 string "Source file for built-in dtb" 436 depends on BUILTIN_DTB 437 help 438 Base name (without suffix, relative to arch/loongarch/boot/dts/) 439 for the DTS file that will be used to produce the DTB linked into 440 the kernel. 441 442config DMI 443 bool "Enable DMI scanning" 444 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 445 default y 446 help 447 This enables SMBIOS/DMI feature for systems, and scanning of 448 DMI to identify machine quirks. 449 450config EFI 451 bool "EFI runtime service support" 452 select UCS2_STRING 453 select EFI_RUNTIME_WRAPPERS 454 help 455 This enables the kernel to use EFI runtime services that are 456 available (such as the EFI variable services). 457 458config EFI_STUB 459 bool "EFI boot stub support" 460 default y 461 depends on EFI 462 select EFI_GENERIC_STUB 463 help 464 This kernel feature allows the kernel to be loaded directly by 465 EFI firmware without the use of a bootloader. 466 467config SMP 468 bool "Multi-Processing support" 469 help 470 This enables support for systems with more than one CPU. If you have 471 a system with only one CPU, say N. If you have a system with more 472 than one CPU, say Y. 473 474 If you say N here, the kernel will run on uni- and multiprocessor 475 machines, but will use only one CPU of a multiprocessor machine. If 476 you say Y here, the kernel will run on many, but not all, 477 uniprocessor machines. On a uniprocessor machine, the kernel 478 will run faster if you say N here. 479 480 See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. 481 482 If you don't know what to do here, say N. 483 484config HOTPLUG_CPU 485 bool "Support for hot-pluggable CPUs" 486 depends on SMP 487 select GENERIC_IRQ_MIGRATION 488 help 489 Say Y here to allow turning CPUs off and on. CPUs can be 490 controlled through /sys/devices/system/cpu. 491 (Note: power management support will enable this option 492 automatically on SMP systems. ) 493 Say N if you want to disable CPU hotplug. 494 495config NR_CPUS 496 int "Maximum number of CPUs (2-2048)" 497 range 2 2048 498 default "2048" 499 depends on SMP 500 help 501 This allows you to specify the maximum number of CPUs which this 502 kernel will support. 503 504config NUMA 505 bool "NUMA Support" 506 select SMP 507 help 508 Say Y to compile the kernel with NUMA (Non-Uniform Memory Access) 509 support. This option improves performance on systems with more 510 than one NUMA node; on single node systems it is generally better 511 to leave it disabled. 512 513config NODES_SHIFT 514 int 515 default "6" 516 depends on NUMA 517 518config ARCH_FORCE_MAX_ORDER 519 int "Maximum zone order" 520 default "13" if PAGE_SIZE_64KB 521 default "11" if PAGE_SIZE_16KB 522 default "10" 523 help 524 The kernel memory allocator divides physically contiguous memory 525 blocks into "zones", where each zone is a power of two number of 526 pages. This option selects the largest power of two that the kernel 527 keeps in the memory allocator. If you need to allocate very large 528 blocks of physically contiguous memory, then you may need to 529 increase this value. 530 531 The page size is not necessarily 4KB. Keep this in mind 532 when choosing a value for this option. 533 534config ARCH_IOREMAP 535 bool "Enable LoongArch DMW-based ioremap()" 536 help 537 We use generic TLB-based ioremap() by default since it has page 538 protection support. However, you can enable LoongArch DMW-based 539 ioremap() for better performance. 540 541config ARCH_WRITECOMBINE 542 bool "Enable WriteCombine (WUC) for ioremap()" 543 help 544 LoongArch maintains cache coherency in hardware, but when paired 545 with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which 546 is similar to WriteCombine) is out of the scope of cache coherency 547 machanism for PCIe devices (this is a PCIe protocol violation, which 548 may be fixed in newer chipsets). 549 550 This means WUC can only used for write-only memory regions now, so 551 this option is disabled by default, making WUC silently fallback to 552 SUC for ioremap(). You can enable this option if the kernel is ensured 553 to run on hardware without this bug. 554 555 You can override this setting via writecombine=on/off boot parameter. 556 557config ARCH_STRICT_ALIGN 558 bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT 559 default y 560 help 561 Not all LoongArch cores support h/w unaligned access, we can use 562 -mstrict-align build parameter to prevent unaligned accesses. 563 564 CPUs with h/w unaligned access support: 565 Loongson-2K2000/2K3000 and all of Loongson-3 series processors 566 based on LoongArch. 567 568 CPUs without h/w unaligned access support: 569 Loongson-2K0300/2K0500/2K1000. 570 571 If you want to make sure whether to support unaligned memory access 572 on your hardware, please read the bit 20 (UAL) of CPUCFG1 register. 573 574 This option is enabled by default to make the kernel be able to run 575 on all LoongArch systems. But you can disable it manually if you want 576 to run kernel only on systems with h/w unaligned access support in 577 order to optimise for performance. 578 579config CPU_HAS_AMO 580 bool 581 default 64BIT 582 583config CPU_HAS_FPU 584 bool 585 default y 586 587config CPU_HAS_LSX 588 bool "Support for the Loongson SIMD Extension" 589 depends on AS_HAS_LSX_EXTENSION 590 help 591 Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers 592 and a set of SIMD instructions to operate on them. When this option 593 is enabled the kernel will support allocating & switching LSX 594 vector register contexts. If you know that your kernel will only be 595 running on CPUs which do not support LSX or that your userland will 596 not be making use of it then you may wish to say N here to reduce 597 the size & complexity of your kernel. 598 599 If unsure, say Y. 600 601config CPU_HAS_LASX 602 bool "Support for the Loongson Advanced SIMD Extension" 603 depends on CPU_HAS_LSX 604 depends on AS_HAS_LASX_EXTENSION 605 help 606 Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector 607 registers and a set of SIMD instructions to operate on them. When this 608 option is enabled the kernel will support allocating & switching LASX 609 vector register contexts. If you know that your kernel will only be 610 running on CPUs which do not support LASX or that your userland will 611 not be making use of it then you may wish to say N here to reduce 612 the size & complexity of your kernel. 613 614 If unsure, say Y. 615 616config CPU_HAS_LBT 617 bool "Support for the Loongson Binary Translation Extension" 618 depends on AS_HAS_LBT_EXTENSION 619 help 620 Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0 621 to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop). 622 Enabling this option allows the kernel to allocate and switch registers 623 specific to LBT. 624 625 If you want to use this feature, such as the Loongson Architecture 626 Translator (LAT), say Y. 627 628config CPU_HAS_PREFETCH 629 bool 630 default y 631 632config ARCH_SUPPORTS_KEXEC 633 def_bool y 634 635config ARCH_SUPPORTS_KEXEC_FILE 636 def_bool 64BIT 637 638config ARCH_SELECTS_KEXEC_FILE 639 def_bool 64BIT 640 depends on KEXEC_FILE 641 select KEXEC_ELF 642 select RELOCATABLE 643 select HAVE_IMA_KEXEC if IMA 644 645config ARCH_SUPPORTS_CRASH_DUMP 646 def_bool y 647 648config ARCH_DEFAULT_CRASH_DUMP 649 def_bool y 650 651config ARCH_SELECTS_CRASH_DUMP 652 def_bool y 653 depends on CRASH_DUMP 654 select RELOCATABLE 655 656config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 657 def_bool CRASH_RESERVE 658 659config RELOCATABLE 660 bool "Relocatable kernel" 661 select ARCH_HAS_RELR 662 help 663 This builds the kernel as a Position Independent Executable (PIE), 664 which retains all relocation metadata required, so as to relocate 665 the kernel binary at runtime to a different virtual address from 666 its link address. 667 668config RANDOMIZE_BASE 669 bool "Randomize the address of the kernel (KASLR)" 670 depends on RELOCATABLE 671 help 672 Randomizes the physical and virtual address at which the 673 kernel image is loaded, as a security feature that 674 deters exploit attempts relying on knowledge of the location 675 of kernel internals. 676 677 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET. 678 679 If unsure, say N. 680 681config RANDOMIZE_BASE_MAX_OFFSET 682 hex "Maximum KASLR offset" if EXPERT 683 depends on RANDOMIZE_BASE 684 range 0x0 0x10000000 685 default "0x01000000" 686 help 687 When KASLR is active, this provides the maximum offset that will 688 be applied to the kernel image. It should be set according to the 689 amount of physical RAM available in the target system. 690 691 This is limited by the size of the lower address memory, 256MB. 692 693source "kernel/livepatch/Kconfig" 694 695config PARAVIRT 696 bool "Enable paravirtualization code" 697 depends on AS_HAS_LVZ_EXTENSION 698 select HAVE_PV_STEAL_CLOCK_GEN 699 help 700 This changes the kernel so it can modify itself when it is run 701 under a hypervisor, potentially improving performance significantly 702 over full virtualization. However, when run without a hypervisor 703 the kernel is theoretically slower and slightly larger. 704 705config PARAVIRT_TIME_ACCOUNTING 706 bool "Paravirtual steal time accounting" 707 depends on PARAVIRT 708 help 709 Select this option to enable fine granularity task steal time 710 accounting. Time spent executing other tasks in parallel with 711 the current vCPU is discounted from the vCPU power. To account for 712 that, there can be a small performance impact. 713 714 If in doubt, say N here. 715 716endmenu 717 718config ARCH_SELECT_MEMORY_MODEL 719 def_bool y 720 721config ARCH_FLATMEM_ENABLE 722 def_bool y 723 depends on !NUMA 724 725config ARCH_SPARSEMEM_ENABLE 726 def_bool y 727 select SPARSEMEM_VMEMMAP_ENABLE 728 help 729 Say Y to support efficient handling of sparse physical memory, 730 for architectures which are either NUMA (Non-Uniform Memory Access) 731 or have huge holes in the physical address space for other reasons. 732 See <file:Documentation/mm/numa.rst> for more. 733 734config ARCH_MEMORY_PROBE 735 def_bool y 736 depends on MEMORY_HOTPLUG 737 738config MMU 739 bool 740 default y 741 742config ARCH_MMAP_RND_BITS_MIN 743 default 12 744 745config ARCH_MMAP_RND_BITS_MAX 746 default 18 747 748config ARCH_SUPPORTS_UPROBES 749 def_bool y 750 751config KASAN_SHADOW_OFFSET 752 hex 753 default 0x0 754 depends on KASAN 755 756menu "Power management options" 757 758config ARCH_SUSPEND_POSSIBLE 759 def_bool y 760 761config ARCH_HIBERNATION_POSSIBLE 762 def_bool y 763 764source "kernel/power/Kconfig" 765source "drivers/acpi/Kconfig" 766source "drivers/cpufreq/Kconfig" 767 768endmenu 769 770source "arch/loongarch/kvm/Kconfig" 771