1# SPDX-License-Identifier: GPL-2.0-only 2# 3# For a description of the syntax of this configuration file, 4# see Documentation/kbuild/kconfig-language.rst. 5# 6 7config 64BIT 8 bool 9 10config 32BIT 11 bool 12 13config RISCV 14 def_bool y 15 select ACPI_GENERIC_GSI if ACPI 16 select ACPI_MCFG if (ACPI && PCI) 17 select ACPI_PPTT if ACPI 18 select ACPI_REDUCED_HARDWARE_ONLY if ACPI 19 select ACPI_SPCR_TABLE if ACPI 20 select ARCH_DMA_DEFAULT_COHERENT 21 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 22 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM_VMEMMAP 23 select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG 24 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 25 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 26 select ARCH_HAS_BINFMT_FLAT 27 select ARCH_HAS_CRC32 if RISCV_ISA_ZBC 28 select ARCH_HAS_CRC64 if 64BIT && RISCV_ISA_ZBC 29 select ARCH_HAS_CRC_T10DIF if RISCV_ISA_ZBC 30 select ARCH_HAS_CURRENT_STACK_POINTER 31 select ARCH_HAS_DEBUG_VIRTUAL if MMU 32 select ARCH_HAS_DEBUG_VM_PGTABLE 33 select ARCH_HAS_DEBUG_WX 34 select ARCH_HAS_FAST_MULTIPLIER 35 select ARCH_HAS_FORTIFY_SOURCE 36 select ARCH_HAS_GCOV_PROFILE_ALL 37 select ARCH_HAS_GIGANTIC_PAGE 38 select ARCH_HAS_HW_PTE_YOUNG 39 select ARCH_HAS_KCOV 40 select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU 41 select ARCH_HAS_MEMBARRIER_CALLBACKS 42 select ARCH_HAS_MEMBARRIER_SYNC_CORE 43 select ARCH_HAS_MMIOWB 44 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 45 select ARCH_HAS_PMEM_API 46 select ARCH_HAS_PREEMPT_LAZY 47 select ARCH_HAS_PREPARE_SYNC_CORE_CMD 48 select ARCH_HAS_PTDUMP if MMU 49 select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU 50 select ARCH_HAS_PTE_SPECIAL 51 select ARCH_HAS_SET_DIRECT_MAP if MMU 52 select ARCH_HAS_SET_MEMORY if MMU 53 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 54 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 55 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 56 select ARCH_HAS_SYSCALL_WRAPPER 57 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 58 select ARCH_HAS_UBSAN 59 select ARCH_HAS_VDSO_ARCH_DATA if GENERIC_VDSO_DATA_STORE 60 select ARCH_KEEP_MEMBLOCK if ACPI 61 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if 64BIT && MMU 62 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 63 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 64 select ARCH_STACKWALK 65 select ARCH_SUPPORTS_ATOMIC_RMW 66 # clang >= 17: https://github.com/llvm/llvm-project/commit/62fa708ceb027713b386c7e0efda994f8bdc27e2 67 select ARCH_SUPPORTS_CFI_CLANG if CLANG_VERSION >= 170000 68 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 69 select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE 70 select ARCH_SUPPORTS_HUGETLBFS if MMU 71 # LLD >= 14: https://github.com/llvm/llvm-project/issues/50505 72 select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000 73 select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000 74 select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS if 64BIT && MMU 75 select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU 76 select ARCH_SUPPORTS_PER_VMA_LOCK if MMU 77 select ARCH_SUPPORTS_RT 78 select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK 79 select ARCH_USE_CMPXCHG_LOCKREF if 64BIT 80 select ARCH_USE_MEMTEST 81 select ARCH_USE_QUEUED_RWLOCKS 82 select ARCH_USE_SYM_ANNOTATIONS 83 select ARCH_USES_CFI_TRAPS if CFI_CLANG 84 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU 85 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 86 select ARCH_WANT_FRAME_POINTERS 87 select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT 88 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 89 select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL 90 select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP 91 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 92 select ARCH_WANTS_NO_INSTR 93 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 94 select ARCH_WEAK_RELEASE_ACQUIRE if ARCH_USE_QUEUED_SPINLOCKS 95 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 96 select BUILDTIME_TABLE_SORT if MMU 97 select CLINT_TIMER if RISCV_M_MODE 98 select CLONE_BACKWARDS 99 select COMMON_CLK 100 select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND 101 select DYNAMIC_FTRACE if FUNCTION_TRACER 102 select EDAC_SUPPORT 103 select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) 104 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE 105 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS 106 select GENERIC_ARCH_TOPOLOGY 107 select GENERIC_ATOMIC64 if !64BIT 108 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 109 select GENERIC_CPU_DEVICES 110 select GENERIC_CPU_VULNERABILITIES 111 select GENERIC_EARLY_IOREMAP 112 select GENERIC_ENTRY 113 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 114 select GENERIC_IDLE_POLL_SETUP 115 select GENERIC_IOREMAP if MMU 116 select GENERIC_IRQ_IPI if SMP 117 select GENERIC_IRQ_IPI_MUX if SMP 118 select GENERIC_IRQ_MULTI_HANDLER 119 select GENERIC_IRQ_SHOW 120 select GENERIC_IRQ_SHOW_LEVEL 121 select GENERIC_LIB_DEVMEM_IS_ALLOWED 122 select GENERIC_PENDING_IRQ if SMP 123 select GENERIC_PCI_IOMAP 124 select GENERIC_SCHED_CLOCK 125 select GENERIC_SMP_IDLE_THREAD 126 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 127 select GENERIC_VDSO_DATA_STORE if MMU 128 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 129 select HARDIRQS_SW_RESEND 130 select HAS_IOPORT if MMU 131 select HAVE_ALIGNED_STRUCT_PAGE 132 select HAVE_ARCH_AUDITSYSCALL 133 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP 134 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT 135 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 136 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 137 select HAVE_ARCH_KASAN if MMU && 64BIT 138 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 139 select HAVE_ARCH_KFENCE if MMU && 64BIT 140 select HAVE_ARCH_KGDB if !XIP_KERNEL 141 select HAVE_ARCH_KGDB_QXFER_PKT 142 select HAVE_ARCH_MMAP_RND_BITS if MMU 143 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 144 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 145 select HAVE_ARCH_SECCOMP_FILTER 146 select HAVE_ARCH_STACKLEAK 147 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 148 select HAVE_ARCH_TRACEHOOK 149 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 150 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if 64BIT && MMU 151 select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD 152 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 153 select HAVE_ASM_MODVERSIONS 154 select HAVE_CONTEXT_TRACKING_USER 155 select HAVE_DEBUG_KMEMLEAK 156 select HAVE_DMA_CONTIGUOUS if MMU 157 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) 158 select FUNCTION_ALIGNMENT_4B if HAVE_DYNAMIC_FTRACE && RISCV_ISA_C 159 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS if HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS 160 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG) 161 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE 162 select HAVE_FTRACE_GRAPH_FUNC 163 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 164 select HAVE_FUNCTION_GRAPH_TRACER if HAVE_DYNAMIC_FTRACE_WITH_ARGS 165 select HAVE_FUNCTION_GRAPH_FREGS 166 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && HAVE_DYNAMIC_FTRACE 167 select HAVE_EBPF_JIT if MMU 168 select HAVE_GUP_FAST if MMU 169 select HAVE_FUNCTION_ARG_ACCESS_API 170 select HAVE_FUNCTION_ERROR_INJECTION 171 select HAVE_GCC_PLUGINS 172 select HAVE_GENERIC_VDSO if MMU && 64BIT 173 select HAVE_IRQ_TIME_ACCOUNTING 174 select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT 175 select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT 176 select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT 177 select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT 178 select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT 179 select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT 180 select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT 181 select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT 182 select HAVE_KPROBES if !XIP_KERNEL 183 select HAVE_KRETPROBES if !XIP_KERNEL 184 # https://github.com/ClangBuiltLinux/linux/issues/1881 185 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD 186 select HAVE_MOVE_PMD 187 select HAVE_MOVE_PUD 188 select HAVE_PAGE_SIZE_4KB 189 select HAVE_PCI 190 select HAVE_PERF_EVENTS 191 select HAVE_PERF_REGS 192 select HAVE_PERF_USER_STACK_DUMP 193 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 194 select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL 195 select HAVE_REGS_AND_STACK_ACCESS_API 196 select HAVE_RETHOOK if !XIP_KERNEL 197 select HAVE_RSEQ 198 select HAVE_RUST if RUSTC_SUPPORTS_RISCV && CC_IS_CLANG 199 select HAVE_SAMPLE_FTRACE_DIRECT 200 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 201 select HAVE_STACKPROTECTOR 202 select HAVE_SYSCALL_TRACEPOINTS 203 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 204 select IRQ_DOMAIN 205 select IRQ_FORCED_THREADING 206 select KASAN_VMALLOC if KASAN 207 select LOCK_MM_AND_FIND_VMA 208 select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU 209 select MODULES_USE_ELF_RELA if MODULES 210 select OF 211 select OF_EARLY_FLATTREE 212 select OF_IRQ 213 select PCI_DOMAINS_GENERIC if PCI 214 select PCI_ECAM if (ACPI && PCI) 215 select PCI_MSI if PCI 216 select RELOCATABLE if !MMU && !PHYS_RAM_BASE_FIXED 217 select RISCV_ALTERNATIVE if !XIP_KERNEL 218 select RISCV_APLIC 219 select RISCV_IMSIC 220 select RISCV_INTC 221 select RISCV_TIMER if RISCV_SBI 222 select SIFIVE_PLIC 223 select SPARSE_IRQ 224 select SYSCTL_EXCEPTION_TRACE 225 select THREAD_INFO_IN_TASK 226 select TRACE_IRQFLAGS_SUPPORT 227 select UACCESS_MEMCPY if !MMU 228 select VDSO_GETRANDOM if HAVE_GENERIC_VDSO 229 select USER_STACKTRACE_SUPPORT 230 select ZONE_DMA32 if 64BIT 231 232config RUSTC_SUPPORTS_RISCV 233 def_bool y 234 depends on 64BIT 235 # Shadow call stack requires rustc version 1.82+ due to use of the 236 # -Zsanitizer=shadow-call-stack flag. 237 depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 238 239config CLANG_SUPPORTS_DYNAMIC_FTRACE 240 def_bool CC_IS_CLANG 241 # https://github.com/ClangBuiltLinux/linux/issues/1817 242 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 243 244config GCC_SUPPORTS_DYNAMIC_FTRACE 245 def_bool CC_IS_GCC 246 depends on $(cc-option,-fpatchable-function-entry=8) 247 depends on CC_HAS_MIN_FUNCTION_ALIGNMENT || !RISCV_ISA_C 248 249config HAVE_SHADOW_CALL_STACK 250 def_bool $(cc-option,-fsanitize=shadow-call-stack) 251 # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769 252 depends on $(ld-option,--no-relax-gp) 253 254config RISCV_USE_LINKER_RELAXATION 255 def_bool y 256 # https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985 257 depends on !LD_IS_LLD || LLD_VERSION >= 150000 258 259# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6 260config ARCH_HAS_BROKEN_DWARF5 261 def_bool y 262 depends on RISCV_USE_LINKER_RELAXATION 263 # https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a 264 depends on AS_IS_LLVM && AS_VERSION < 180000 265 # https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77 266 depends on LD_IS_LLD && LLD_VERSION < 180000 267 268config ARCH_MMAP_RND_BITS_MIN 269 default 18 if 64BIT 270 default 8 271 272config ARCH_MMAP_RND_COMPAT_BITS_MIN 273 default 8 274 275# max bits determined by the following formula: 276# VA_BITS - PAGE_SHIFT - 3 277config ARCH_MMAP_RND_BITS_MAX 278 default 24 if 64BIT # SV39 based 279 default 17 280 281config ARCH_MMAP_RND_COMPAT_BITS_MAX 282 default 17 283 284# set if we run in machine mode, cleared if we run in supervisor mode 285config RISCV_M_MODE 286 bool "Build a kernel that runs in machine mode" 287 depends on !MMU 288 default y 289 help 290 Select this option if you want to run the kernel in M-mode, 291 without the assistance of any other firmware. 292 293# set if we are running in S-mode and can use SBI calls 294config RISCV_SBI 295 bool 296 depends on !RISCV_M_MODE 297 default y 298 299config MMU 300 bool "MMU-based Paged Memory Management Support" 301 default y 302 help 303 Select if you want MMU-based virtualised addressing space 304 support by paged memory management. If unsure, say 'Y'. 305 306config KASAN_SHADOW_OFFSET 307 hex 308 depends on KASAN_GENERIC 309 default 0xdfffffff00000000 if 64BIT 310 default 0xffffffff if 32BIT 311 312config ARCH_FLATMEM_ENABLE 313 def_bool !NUMA 314 315config ARCH_SPARSEMEM_ENABLE 316 def_bool y 317 depends on MMU 318 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 319 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 320 321config ARCH_SELECT_MEMORY_MODEL 322 def_bool ARCH_SPARSEMEM_ENABLE 323 324config ARCH_SUPPORTS_UPROBES 325 def_bool y 326 327config STACKTRACE_SUPPORT 328 def_bool y 329 330config GENERIC_BUG 331 def_bool y 332 depends on BUG 333 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 334 335config GENERIC_BUG_RELATIVE_POINTERS 336 bool 337 338config GENERIC_CALIBRATE_DELAY 339 def_bool y 340 341config GENERIC_CSUM 342 def_bool y 343 344config GENERIC_HWEIGHT 345 def_bool y 346 347config FIX_EARLYCON_MEM 348 def_bool MMU 349 350config ILLEGAL_POINTER_VALUE 351 hex 352 default 0 if 32BIT 353 default 0xdead000000000000 if 64BIT 354 355config PGTABLE_LEVELS 356 int 357 default 5 if 64BIT 358 default 2 359 360config LOCKDEP_SUPPORT 361 def_bool y 362 363config RISCV_DMA_NONCOHERENT 364 bool 365 select ARCH_HAS_DMA_PREP_COHERENT 366 select ARCH_HAS_SETUP_DMA_OPS 367 select ARCH_HAS_SYNC_DMA_FOR_CPU 368 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 369 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 370 371config RISCV_NONSTANDARD_CACHE_OPS 372 bool 373 help 374 This enables function pointer support for non-standard noncoherent 375 systems to handle cache management. 376 377config AS_HAS_INSN 378 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 379 380config AS_HAS_OPTION_ARCH 381 # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4 382 def_bool y 383 depends on $(as-instr, .option arch$(comma) +m) 384 385source "arch/riscv/Kconfig.socs" 386source "arch/riscv/Kconfig.errata" 387 388menu "Platform type" 389 390config NONPORTABLE 391 bool "Allow configurations that result in non-portable kernels" 392 help 393 RISC-V kernel binaries are compatible between all known systems 394 whenever possible, but there are some use cases that can only be 395 satisfied by configurations that result in kernel binaries that are 396 not portable between systems. 397 398 Selecting N does not guarantee kernels will be portable to all known 399 systems. Selecting any of the options guarded by NONPORTABLE will 400 result in kernel binaries that are unlikely to be portable between 401 systems. 402 403 If unsure, say N. 404 405choice 406 prompt "Base ISA" 407 default ARCH_RV64I 408 help 409 This selects the base ISA that this kernel will target and must match 410 the target platform. 411 412config ARCH_RV32I 413 bool "RV32I" 414 depends on NONPORTABLE 415 select 32BIT 416 select GENERIC_LIB_ASHLDI3 417 select GENERIC_LIB_ASHRDI3 418 select GENERIC_LIB_LSHRDI3 419 select GENERIC_LIB_UCMPDI2 420 421config ARCH_RV64I 422 bool "RV64I" 423 select 64BIT 424 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 425 select SWIOTLB if MMU 426 427endchoice 428 429# We must be able to map all physical memory into the kernel, but the compiler 430# is still a bit more efficient when generating code if it's setup in a manner 431# such that it can only map 2GiB of memory. 432choice 433 prompt "Kernel Code Model" 434 default CMODEL_MEDLOW if 32BIT 435 default CMODEL_MEDANY if 64BIT 436 437 config CMODEL_MEDLOW 438 bool "medium low code model" 439 config CMODEL_MEDANY 440 bool "medium any code model" 441endchoice 442 443config MODULE_SECTIONS 444 bool 445 select HAVE_MOD_ARCH_SPECIFIC 446 447config SMP 448 bool "Symmetric Multi-Processing" 449 help 450 This enables support for systems with more than one CPU. If 451 you say N here, the kernel will run on single and 452 multiprocessor machines, but will use only one CPU of a 453 multiprocessor machine. If you say Y here, the kernel will run 454 on many, but not all, single processor machines. On a single 455 processor machine, the kernel will run faster if you say N 456 here. 457 458 If you don't know what to do here, say N. 459 460config SCHED_MC 461 bool "Multi-core scheduler support" 462 depends on SMP 463 help 464 Multi-core scheduler support improves the CPU scheduler's decision 465 making when dealing with multi-core CPU chips at a cost of slightly 466 increased overhead in some places. If unsure say N here. 467 468config NR_CPUS 469 int "Maximum number of CPUs (2-512)" 470 depends on SMP 471 range 2 512 if !RISCV_SBI_V01 472 range 2 32 if RISCV_SBI_V01 && 32BIT 473 range 2 64 if RISCV_SBI_V01 && 64BIT 474 default "32" if 32BIT 475 default "64" if 64BIT 476 477config HOTPLUG_CPU 478 bool "Support for hot-pluggable CPUs" 479 depends on SMP 480 select GENERIC_IRQ_MIGRATION 481 help 482 483 Say Y here to experiment with turning CPUs off and on. CPUs 484 can be controlled through /sys/devices/system/cpu. 485 486 Say N if you want to disable CPU hotplug. 487 488choice 489 prompt "CPU Tuning" 490 default TUNE_GENERIC 491 492config TUNE_GENERIC 493 bool "generic" 494 495endchoice 496 497# Common NUMA Features 498config NUMA 499 bool "NUMA Memory Allocation and Scheduler Support" 500 depends on SMP && MMU 501 select ARCH_SUPPORTS_NUMA_BALANCING 502 select GENERIC_ARCH_NUMA 503 select HAVE_SETUP_PER_CPU_AREA 504 select NEED_PER_CPU_EMBED_FIRST_CHUNK 505 select NEED_PER_CPU_PAGE_FIRST_CHUNK 506 select OF_NUMA 507 select USE_PERCPU_NUMA_NODE_ID 508 help 509 Enable NUMA (Non-Uniform Memory Access) support. 510 511 The kernel will try to allocate memory used by a CPU on the 512 local memory of the CPU and add some more NUMA awareness to the kernel. 513 514config NODES_SHIFT 515 int "Maximum NUMA Nodes (as a power of 2)" 516 range 1 10 517 default "2" 518 depends on NUMA 519 help 520 Specify the maximum number of NUMA Nodes available on the target 521 system. Increases memory reserved to accommodate various tables. 522 523choice 524 prompt "RISC-V spinlock type" 525 default RISCV_COMBO_SPINLOCKS 526 527config RISCV_TICKET_SPINLOCKS 528 bool "Using ticket spinlock" 529 530config RISCV_QUEUED_SPINLOCKS 531 bool "Using queued spinlock" 532 depends on SMP && MMU && NONPORTABLE 533 select ARCH_USE_QUEUED_SPINLOCKS 534 help 535 The queued spinlock implementation requires the forward progress 536 guarantee of cmpxchg()/xchg() atomic operations: CAS with Zabha or 537 LR/SC with Ziccrse provide such guarantee. 538 539 Select this if and only if Zabha or Ziccrse is available on your 540 platform, RISCV_QUEUED_SPINLOCKS must not be selected for platforms 541 without one of those extensions. 542 543 If unsure, select RISCV_COMBO_SPINLOCKS, which will use qspinlocks 544 when supported and otherwise ticket spinlocks. 545 546config RISCV_COMBO_SPINLOCKS 547 bool "Using combo spinlock" 548 depends on SMP && MMU 549 select ARCH_USE_QUEUED_SPINLOCKS 550 help 551 Embed both queued spinlock and ticket lock so that the spinlock 552 implementation can be chosen at runtime. 553 554endchoice 555 556config RISCV_ALTERNATIVE 557 bool 558 depends on !XIP_KERNEL 559 help 560 This Kconfig allows the kernel to automatically patch the 561 erratum or cpufeature required by the execution platform at run 562 time. The code patching overhead is minimal, as it's only done 563 once at boot and once on each module load. 564 565config RISCV_ALTERNATIVE_EARLY 566 bool 567 depends on RISCV_ALTERNATIVE 568 help 569 Allows early patching of the kernel for special errata 570 571config RISCV_ISA_C 572 bool "Emit compressed instructions when building Linux" 573 default y 574 help 575 Adds "C" to the ISA subsets that the toolchain is allowed to emit 576 when building Linux, which results in compressed instructions in the 577 Linux binary. This option produces a kernel that will not run on 578 systems that do not support compressed instructions. 579 580 If you don't know what to do here, say Y. 581 582config RISCV_ISA_SUPM 583 bool "Supm extension for userspace pointer masking" 584 depends on 64BIT 585 default y 586 help 587 Add support for pointer masking in userspace (Supm) when the 588 underlying hardware extension (Smnpm or Ssnpm) is detected at boot. 589 590 If this option is disabled, userspace will be unable to use 591 the prctl(PR_{SET,GET}_TAGGED_ADDR_CTRL) API. 592 593config RISCV_ISA_SVNAPOT 594 bool "Svnapot extension support for supervisor mode NAPOT pages" 595 depends on 64BIT && MMU 596 depends on RISCV_ALTERNATIVE 597 default y 598 help 599 Enable support for the Svnapot ISA-extension when it is detected 600 at boot. 601 602 The Svnapot extension is used to mark contiguous PTEs as a range 603 of contiguous virtual-to-physical translations for a naturally 604 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 605 size. When HUGETLBFS is also selected this option unconditionally 606 allocates some memory for each NAPOT page size supported by the kernel. 607 When optimizing for low memory consumption and for platforms without 608 the Svnapot extension, it may be better to say N here. 609 610 If you don't know what to do here, say Y. 611 612config RISCV_ISA_SVPBMT 613 bool "Svpbmt extension support for supervisor mode page-based memory types" 614 depends on 64BIT && MMU 615 depends on RISCV_ALTERNATIVE 616 default y 617 help 618 Add support for the Svpbmt ISA-extension (Supervisor-mode: 619 page-based memory types) in the kernel when it is detected at boot. 620 621 The memory type for a page contains a combination of attributes 622 that indicate the cacheability, idempotency, and ordering 623 properties for access to that page. 624 625 The Svpbmt extension is only available on 64-bit cpus. 626 627 If you don't know what to do here, say Y. 628 629config TOOLCHAIN_HAS_V 630 bool 631 default y 632 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv) 633 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv) 634 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 635 depends on AS_HAS_OPTION_ARCH 636 637config RISCV_ISA_V 638 bool "Vector extension support" 639 depends on TOOLCHAIN_HAS_V 640 depends on FPU 641 select DYNAMIC_SIGFRAME 642 default y 643 help 644 Add support for the Vector extension when it is detected at boot. 645 When this option is disabled, neither the kernel nor userspace may 646 use vector procedures. 647 648 If you don't know what to do here, say Y. 649 650config RISCV_ISA_V_DEFAULT_ENABLE 651 bool "Enable userspace Vector by default" 652 depends on RISCV_ISA_V 653 default y 654 help 655 Say Y here if you want to enable Vector in userspace by default. 656 Otherwise, userspace has to make explicit prctl() call to enable 657 Vector, or enable it via the sysctl interface. 658 659 If you don't know what to do here, say Y. 660 661config RISCV_ISA_V_UCOPY_THRESHOLD 662 int "Threshold size for vectorized user copies" 663 depends on RISCV_ISA_V 664 default 768 665 help 666 Prefer using vectorized copy_to_user()/copy_from_user() when the 667 workload size exceeds this value. 668 669config RISCV_ISA_V_PREEMPTIVE 670 bool "Run kernel-mode Vector with kernel preemption" 671 depends on PREEMPTION 672 depends on RISCV_ISA_V 673 default y 674 help 675 Usually, in-kernel SIMD routines are run with preemption disabled. 676 Functions which invoke long running SIMD thus must yield the core's 677 vector unit to prevent blocking other tasks for too long. 678 679 This config allows the kernel to run SIMD without explicitly disabling 680 preemption. Enabling this config will result in higher memory consumption 681 due to the allocation of per-task's kernel Vector context. 682 683config RISCV_ISA_ZAWRS 684 bool "Zawrs extension support for more efficient busy waiting" 685 depends on RISCV_ALTERNATIVE 686 default y 687 help 688 The Zawrs extension defines instructions to be used in polling loops 689 which allow a hart to enter a low-power state or to trap to the 690 hypervisor while waiting on a store to a memory location. Enable the 691 use of these instructions in the kernel when the Zawrs extension is 692 detected at boot. 693 694config TOOLCHAIN_HAS_ZABHA 695 bool 696 default y 697 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zabha) 698 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zabha) 699 depends on AS_HAS_OPTION_ARCH 700 701config RISCV_ISA_ZABHA 702 bool "Zabha extension support for atomic byte/halfword operations" 703 depends on TOOLCHAIN_HAS_ZABHA 704 depends on RISCV_ALTERNATIVE 705 default y 706 help 707 Enable the use of the Zabha ISA-extension to implement kernel 708 byte/halfword atomic memory operations when it is detected at boot. 709 710 If you don't know what to do here, say Y. 711 712config TOOLCHAIN_HAS_ZACAS 713 bool 714 default y 715 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zacas) 716 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zacas) 717 depends on AS_HAS_OPTION_ARCH 718 719config RISCV_ISA_ZACAS 720 bool "Zacas extension support for atomic CAS" 721 depends on TOOLCHAIN_HAS_ZACAS 722 depends on RISCV_ALTERNATIVE 723 default y 724 help 725 Enable the use of the Zacas ISA-extension to implement kernel atomic 726 cmpxchg operations when it is detected at boot. 727 728 If you don't know what to do here, say Y. 729 730config TOOLCHAIN_HAS_ZBB 731 bool 732 default y 733 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 734 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 735 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 736 depends on AS_HAS_OPTION_ARCH 737 738# This symbol indicates that the toolchain supports all v1.0 vector crypto 739# extensions, including Zvk*, Zvbb, and Zvbc. LLVM added all of these at once. 740# binutils added all except Zvkb, then added Zvkb. So we just check for Zvkb. 741config TOOLCHAIN_HAS_VECTOR_CRYPTO 742 def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb) 743 depends on AS_HAS_OPTION_ARCH 744 745config TOOLCHAIN_HAS_ZBA 746 bool 747 default y 748 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zba) 749 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zba) 750 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 751 depends on AS_HAS_OPTION_ARCH 752 753config RISCV_ISA_ZBA 754 bool "Zba extension support for bit manipulation instructions" 755 default y 756 help 757 Add support for enabling optimisations in the kernel when the Zba 758 extension is detected at boot. 759 760 The Zba extension provides instructions to accelerate the generation 761 of addresses that index into arrays of basic data types. 762 763 If you don't know what to do here, say Y. 764 765config RISCV_ISA_ZBB 766 bool "Zbb extension support for bit manipulation instructions" 767 depends on RISCV_ALTERNATIVE 768 default y 769 help 770 Add support for enabling optimisations in the kernel when the 771 Zbb extension is detected at boot. Some optimisations may 772 additionally depend on toolchain support for Zbb. 773 774 The Zbb extension provides instructions to accelerate a number 775 of bit-specific operations (count bit population, sign extending, 776 bitrotation, etc). 777 778 If you don't know what to do here, say Y. 779 780config TOOLCHAIN_HAS_ZBC 781 bool 782 default y 783 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc) 784 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc) 785 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 786 depends on AS_HAS_OPTION_ARCH 787 788config RISCV_ISA_ZBC 789 bool "Zbc extension support for carry-less multiplication instructions" 790 depends on TOOLCHAIN_HAS_ZBC 791 depends on MMU 792 depends on RISCV_ALTERNATIVE 793 default y 794 help 795 Adds support to dynamically detect the presence of the Zbc 796 extension (carry-less multiplication) and enable its usage. 797 798 The Zbc extension could accelerate CRC (cyclic redundancy check) 799 calculations. 800 801 If you don't know what to do here, say Y. 802 803config TOOLCHAIN_HAS_ZBKB 804 bool 805 default y 806 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbkb) 807 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbkb) 808 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 809 depends on AS_HAS_OPTION_ARCH 810 811config RISCV_ISA_ZBKB 812 bool "Zbkb extension support for bit manipulation instructions" 813 depends on TOOLCHAIN_HAS_ZBKB 814 depends on RISCV_ALTERNATIVE 815 default y 816 help 817 Adds support to dynamically detect the presence of the ZBKB 818 extension (bit manipulation for cryptography) and enable its usage. 819 820 The Zbkb extension provides instructions to accelerate a number 821 of common cryptography operations (pack, zip, etc). 822 823 If you don't know what to do here, say Y. 824 825config RISCV_ISA_ZICBOM 826 bool "Zicbom extension support for non-coherent DMA operation" 827 depends on MMU 828 depends on RISCV_ALTERNATIVE 829 default y 830 select RISCV_DMA_NONCOHERENT 831 select DMA_DIRECT_REMAP 832 help 833 Add support for the Zicbom extension (Cache Block Management 834 Operations) and enable its use in the kernel when it is detected 835 at boot. 836 837 The Zicbom extension can be used to handle for example 838 non-coherent DMA support on devices that need it. 839 840 If you don't know what to do here, say Y. 841 842config RISCV_ISA_ZICBOZ 843 bool "Zicboz extension support for faster zeroing of memory" 844 depends on RISCV_ALTERNATIVE 845 default y 846 help 847 Enable the use of the Zicboz extension (cbo.zero instruction) 848 in the kernel when it is detected at boot. 849 850 The Zicboz extension is used for faster zeroing of memory. 851 852 If you don't know what to do here, say Y. 853 854config RISCV_ISA_ZICBOP 855 bool "Zicbop extension support for cache block prefetch" 856 depends on MMU 857 depends on RISCV_ALTERNATIVE 858 default y 859 help 860 Adds support to dynamically detect the presence of the ZICBOP 861 extension (Cache Block Prefetch Operations) and enable its 862 usage. 863 864 The Zicbop extension can be used to prefetch cache blocks for 865 read/write fetch. 866 867 If you don't know what to do here, say Y. 868 869config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 870 def_bool y 871 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 872 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 873 depends on AS_IS_GNU && AS_VERSION >= 23600 874 help 875 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 876 20191213 version, which moves some instructions from the I extension to 877 the Zicsr and Zifencei extensions. This requires explicitly specifying 878 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 879 and Zifencei are supported in binutils from version 2.36 onwards. 880 To make life easier, and avoid forcing toolchains that default to a 881 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 882 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 883 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 884 885config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 886 def_bool y 887 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 888 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 889 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 890 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 891 help 892 Certain versions of clang and GCC do not support zicsr and zifencei via 893 -march. This option causes an older ISA spec compatible with these older 894 versions of clang and GCC to be passed to GAS, which has the same result 895 as passing zicsr and zifencei to -march. 896 897config FPU 898 bool "FPU support" 899 default y 900 help 901 Add support for floating point operations when an FPU is detected at 902 boot. When this option is disabled, neither the kernel nor userspace 903 may use the floating point unit. 904 905 If you don't know what to do here, say Y. 906 907config IRQ_STACKS 908 bool "Independent irq & softirq stacks" if EXPERT 909 default y 910 select HAVE_IRQ_EXIT_ON_IRQ_STACK 911 select HAVE_SOFTIRQ_ON_OWN_STACK 912 help 913 Add independent irq & softirq stacks for percpu to prevent kernel stack 914 overflows. We may save some memory footprint by disabling IRQ_STACKS. 915 916config THREAD_SIZE_ORDER 917 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 918 range 0 4 919 default 1 if 32BIT 920 default 2 921 help 922 Specify the Pages of thread stack size (from 4KB to 64KB), which also 923 affects irq stack size, which is equal to thread stack size. 924 925config RISCV_MISALIGNED 926 bool 927 help 928 Embed support for detecting and emulating misaligned 929 scalar or vector loads and stores. 930 931config RISCV_SCALAR_MISALIGNED 932 bool 933 select RISCV_MISALIGNED 934 select SYSCTL_ARCH_UNALIGN_ALLOW 935 help 936 Embed support for emulating misaligned loads and stores. 937 938config RISCV_VECTOR_MISALIGNED 939 bool 940 select RISCV_MISALIGNED 941 depends on RISCV_ISA_V 942 help 943 Enable detecting support for vector misaligned loads and stores. 944 945choice 946 prompt "Unaligned Accesses Support" 947 default RISCV_PROBE_UNALIGNED_ACCESS 948 help 949 This determines the level of support for unaligned accesses. This 950 information is used by the kernel to perform optimizations. It is also 951 exposed to user space via the hwprobe syscall. The hardware will be 952 probed at boot by default. 953 954config RISCV_PROBE_UNALIGNED_ACCESS 955 bool "Probe for hardware unaligned access support" 956 select RISCV_SCALAR_MISALIGNED 957 help 958 During boot, the kernel will run a series of tests to determine the 959 speed of unaligned accesses. This probing will dynamically determine 960 the speed of unaligned accesses on the underlying system. If unaligned 961 memory accesses trap into the kernel as they are not supported by the 962 system, the kernel will emulate the unaligned accesses to preserve the 963 UABI. 964 965config RISCV_EMULATED_UNALIGNED_ACCESS 966 bool "Emulate unaligned access where system support is missing" 967 select RISCV_SCALAR_MISALIGNED 968 help 969 If unaligned memory accesses trap into the kernel as they are not 970 supported by the system, the kernel will emulate the unaligned 971 accesses to preserve the UABI. When the underlying system does support 972 unaligned accesses, the unaligned accesses are assumed to be slow. 973 974config RISCV_SLOW_UNALIGNED_ACCESS 975 bool "Assume the system supports slow unaligned memory accesses" 976 depends on NONPORTABLE 977 help 978 Assume that the system supports slow unaligned memory accesses. The 979 kernel and userspace programs may not be able to run at all on systems 980 that do not support unaligned memory accesses. 981 982config RISCV_EFFICIENT_UNALIGNED_ACCESS 983 bool "Assume the system supports fast unaligned memory accesses" 984 depends on NONPORTABLE 985 select DCACHE_WORD_ACCESS if MMU 986 select HAVE_EFFICIENT_UNALIGNED_ACCESS 987 help 988 Assume that the system supports fast unaligned memory accesses. When 989 enabled, this option improves the performance of the kernel on such 990 systems. However, the kernel and userspace programs will run much more 991 slowly, or will not be able to run at all, on systems that do not 992 support efficient unaligned memory accesses. 993 994endchoice 995 996choice 997 prompt "Vector unaligned Accesses Support" 998 depends on RISCV_ISA_V 999 default RISCV_PROBE_VECTOR_UNALIGNED_ACCESS 1000 help 1001 This determines the level of support for vector unaligned accesses. This 1002 information is used by the kernel to perform optimizations. It is also 1003 exposed to user space via the hwprobe syscall. The hardware will be 1004 probed at boot by default. 1005 1006config RISCV_PROBE_VECTOR_UNALIGNED_ACCESS 1007 bool "Probe speed of vector unaligned accesses" 1008 select RISCV_VECTOR_MISALIGNED 1009 depends on RISCV_ISA_V 1010 help 1011 During boot, the kernel will run a series of tests to determine the 1012 speed of vector unaligned accesses if they are supported. This probing 1013 will dynamically determine the speed of vector unaligned accesses on 1014 the underlying system if they are supported. 1015 1016config RISCV_SLOW_VECTOR_UNALIGNED_ACCESS 1017 bool "Assume the system supports slow vector unaligned memory accesses" 1018 depends on NONPORTABLE 1019 help 1020 Assume that the system supports slow vector unaligned memory accesses. The 1021 kernel and userspace programs may not be able to run at all on systems 1022 that do not support unaligned memory accesses. 1023 1024config RISCV_EFFICIENT_VECTOR_UNALIGNED_ACCESS 1025 bool "Assume the system supports fast vector unaligned memory accesses" 1026 depends on NONPORTABLE 1027 help 1028 Assume that the system supports fast vector unaligned memory accesses. When 1029 enabled, this option improves the performance of the kernel on such 1030 systems. However, the kernel and userspace programs will run much more 1031 slowly, or will not be able to run at all, on systems that do not 1032 support efficient unaligned memory accesses. 1033 1034endchoice 1035 1036source "arch/riscv/Kconfig.vendor" 1037 1038endmenu # "Platform type" 1039 1040menu "Kernel features" 1041 1042source "kernel/Kconfig.hz" 1043 1044config RISCV_SBI_V01 1045 bool "SBI v0.1 support" 1046 depends on RISCV_SBI 1047 help 1048 This config allows kernel to use SBI v0.1 APIs. This will be 1049 deprecated in future once legacy M-mode software are no longer in use. 1050 1051config RISCV_BOOT_SPINWAIT 1052 bool "Spinwait booting method" 1053 depends on SMP 1054 default y if RISCV_SBI_V01 || RISCV_M_MODE 1055 help 1056 This enables support for booting Linux via spinwait method. In the 1057 spinwait method, all cores randomly jump to Linux. One of the cores 1058 gets chosen via lottery and all other keep spinning on a percpu 1059 variable. This method cannot support CPU hotplug and sparse hartid 1060 scheme. It should be only enabled for M-mode Linux or platforms relying 1061 on older firmware without SBI HSM extension. All other platforms should 1062 rely on ordered booting via SBI HSM extension which gets chosen 1063 dynamically at runtime if the firmware supports it. 1064 1065 Since spinwait is incompatible with sparse hart IDs, it requires 1066 NR_CPUS be large enough to contain the physical hart ID of the first 1067 hart to enter Linux. 1068 1069 If unsure what to do here, say N. 1070 1071config ARCH_SUPPORTS_KEXEC 1072 def_bool y 1073 1074config ARCH_SELECTS_KEXEC 1075 def_bool y 1076 depends on KEXEC 1077 select HOTPLUG_CPU if SMP 1078 1079config ARCH_SUPPORTS_KEXEC_FILE 1080 def_bool 64BIT 1081 1082config ARCH_SELECTS_KEXEC_FILE 1083 def_bool y 1084 depends on KEXEC_FILE 1085 select HAVE_IMA_KEXEC if IMA 1086 select KEXEC_ELF 1087 1088config ARCH_SUPPORTS_KEXEC_PURGATORY 1089 def_bool ARCH_SUPPORTS_KEXEC_FILE 1090 1091config ARCH_SUPPORTS_CRASH_DUMP 1092 def_bool y 1093 1094config ARCH_DEFAULT_CRASH_DUMP 1095 def_bool y 1096 1097config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 1098 def_bool CRASH_RESERVE 1099 1100config COMPAT 1101 bool "Kernel support for 32-bit U-mode" 1102 default 64BIT 1103 depends on 64BIT && MMU 1104 help 1105 This option enables support for a 32-bit U-mode running under a 64-bit 1106 kernel at S-mode. riscv32-specific components such as system calls, 1107 the user helper functions (vdso), signal rt_frame functions and the 1108 ptrace interface are handled appropriately by the kernel. 1109 1110 If you want to execute 32-bit userspace applications, say Y. 1111 1112config PARAVIRT 1113 bool "Enable paravirtualization code" 1114 depends on RISCV_SBI 1115 help 1116 This changes the kernel so it can modify itself when it is run 1117 under a hypervisor, potentially improving performance significantly 1118 over full virtualization. 1119 1120config PARAVIRT_TIME_ACCOUNTING 1121 bool "Paravirtual steal time accounting" 1122 depends on PARAVIRT 1123 help 1124 Select this option to enable fine granularity task steal time 1125 accounting. Time spent executing other tasks in parallel with 1126 the current vCPU is discounted from the vCPU power. To account for 1127 that, there can be a small performance impact. 1128 1129 If in doubt, say N here. 1130 1131config RELOCATABLE 1132 bool "Build a relocatable kernel" 1133 depends on !XIP_KERNEL 1134 select MODULE_SECTIONS if MODULES 1135 select ARCH_VMLINUX_NEEDS_RELOCS 1136 help 1137 This builds a kernel as a Position Independent Executable (PIE), 1138 which retains all relocation metadata required to relocate the 1139 kernel binary at runtime to a different virtual address than the 1140 address it was linked at. 1141 Since RISCV uses the RELA relocation format, this requires a 1142 relocation pass at runtime even if the kernel is loaded at the 1143 same address it was linked at. 1144 1145 If unsure, say N. 1146 1147config RANDOMIZE_BASE 1148 bool "Randomize the address of the kernel image" 1149 select RELOCATABLE 1150 depends on MMU && 64BIT && !XIP_KERNEL 1151 help 1152 Randomizes the virtual address at which the kernel image is 1153 loaded, as a security feature that deters exploit attempts 1154 relying on knowledge of the location of kernel internals. 1155 1156 It is the bootloader's job to provide entropy, by passing a 1157 random u64 value in /chosen/kaslr-seed at kernel entry. 1158 1159 When booting via the UEFI stub, it will invoke the firmware's 1160 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 1161 to the kernel proper. In addition, it will randomise the physical 1162 location of the kernel Image as well. 1163 1164 If unsure, say N. 1165 1166endmenu # "Kernel features" 1167 1168menu "Boot options" 1169 1170config CMDLINE 1171 string "Built-in kernel command line" 1172 help 1173 For most platforms, the arguments for the kernel's command line 1174 are provided at run-time, during boot. However, there are cases 1175 where either no arguments are being provided or the provided 1176 arguments are insufficient or even invalid. 1177 1178 When that occurs, it is possible to define a built-in command 1179 line here and choose how the kernel should use it later on. 1180 1181choice 1182 prompt "Built-in command line usage" 1183 depends on CMDLINE != "" 1184 default CMDLINE_FALLBACK 1185 help 1186 Choose how the kernel will handle the provided built-in command 1187 line. 1188 1189config CMDLINE_FALLBACK 1190 bool "Use bootloader kernel arguments if available" 1191 help 1192 Use the built-in command line as fallback in case we get nothing 1193 during boot. This is the default behaviour. 1194 1195config CMDLINE_EXTEND 1196 bool "Extend bootloader kernel arguments" 1197 help 1198 The built-in command line will be appended to the command- 1199 line arguments provided during boot. This is useful in 1200 cases where the provided arguments are insufficient and 1201 you don't want to or cannot modify them. 1202 1203config CMDLINE_FORCE 1204 bool "Always use the default kernel command string" 1205 help 1206 Always use the built-in command line, even if we get one during 1207 boot. This is useful in case you need to override the provided 1208 command line on systems where you don't have or want control 1209 over it. 1210 1211endchoice 1212 1213config EFI_STUB 1214 bool 1215 1216config EFI 1217 bool "UEFI runtime support" 1218 depends on OF && !XIP_KERNEL 1219 depends on MMU 1220 default y 1221 select ARCH_SUPPORTS_ACPI if 64BIT 1222 select EFI_GENERIC_STUB 1223 select EFI_PARAMS_FROM_FDT 1224 select EFI_RUNTIME_WRAPPERS 1225 select EFI_STUB 1226 select LIBFDT 1227 select RISCV_ISA_C 1228 select UCS2_STRING 1229 help 1230 This option provides support for runtime services provided 1231 by UEFI firmware (such as non-volatile variables, realtime 1232 clock, and platform reset). A UEFI stub is also provided to 1233 allow the kernel to be booted as an EFI application. This 1234 is only useful on systems that have UEFI firmware. 1235 1236config DMI 1237 bool "Enable support for SMBIOS (DMI) tables" 1238 depends on EFI 1239 default y 1240 help 1241 This enables SMBIOS/DMI feature for systems. 1242 1243 This option is only useful on systems that have UEFI firmware. 1244 However, even with this option, the resultant kernel should 1245 continue to boot on existing non-UEFI platforms. 1246 1247config CC_HAVE_STACKPROTECTOR_TLS 1248 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 1249 1250config STACKPROTECTOR_PER_TASK 1251 def_bool y 1252 depends on !RANDSTRUCT 1253 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 1254 1255config PHYS_RAM_BASE_FIXED 1256 bool "Explicitly specified physical RAM address" 1257 depends on NONPORTABLE 1258 default n 1259 1260config PHYS_RAM_BASE 1261 hex "Platform Physical RAM address" 1262 depends on PHYS_RAM_BASE_FIXED 1263 default "0x80000000" 1264 help 1265 This is the physical address of RAM in the system. It has to be 1266 explicitly specified to run early relocations of read-write data 1267 from flash to RAM. 1268 1269config XIP_KERNEL 1270 bool "Kernel Execute-In-Place from ROM" 1271 depends on MMU && SPARSEMEM && NONPORTABLE 1272 # This prevents XIP from being enabled by all{yes,mod}config, which 1273 # fail to build since XIP doesn't support large kernels. 1274 depends on !COMPILE_TEST 1275 select PHYS_RAM_BASE_FIXED 1276 help 1277 Execute-In-Place allows the kernel to run from non-volatile storage 1278 directly addressable by the CPU, such as NOR flash. This saves RAM 1279 space since the text section of the kernel is not loaded from flash 1280 to RAM. Read-write sections, such as the data section and stack, 1281 are still copied to RAM. The XIP kernel is not compressed since 1282 it has to run directly from flash, so it will take more space to 1283 store it. The flash address used to link the kernel object files, 1284 and for storing it, is configuration dependent. Therefore, if you 1285 say Y here, you must know the proper physical address where to 1286 store the kernel image depending on your own flash memory usage. 1287 1288 Also note that the make target becomes "make xipImage" rather than 1289 "make zImage" or "make Image". The final kernel binary to put in 1290 ROM memory will be arch/riscv/boot/xipImage. 1291 1292 SPARSEMEM is required because the kernel text and rodata that are 1293 flash resident are not backed by memmap, then any attempt to get 1294 a struct page on those regions will trigger a fault. 1295 1296 If unsure, say N. 1297 1298config XIP_PHYS_ADDR 1299 hex "XIP Kernel Physical Location" 1300 depends on XIP_KERNEL 1301 default "0x21000000" 1302 help 1303 This is the physical address in your flash memory the kernel will 1304 be linked for and stored to. This address is dependent on your 1305 own flash usage. 1306 1307config RISCV_ISA_FALLBACK 1308 bool "Permit falling back to parsing riscv,isa for extension support by default" 1309 default y 1310 help 1311 Parsing the "riscv,isa" devicetree property has been deprecated and 1312 replaced by a list of explicitly defined strings. For compatibility 1313 with existing platforms, the kernel will fall back to parsing the 1314 "riscv,isa" property if the replacements are not found. 1315 1316 Selecting N here will result in a kernel that does not use the 1317 fallback, unless the commandline "riscv_isa_fallback" parameter is 1318 present. 1319 1320 Please see the dt-binding, located at 1321 Documentation/devicetree/bindings/riscv/extensions.yaml for details 1322 on the replacement properties, "riscv,isa-base" and 1323 "riscv,isa-extensions". 1324 1325config BUILTIN_DTB 1326 bool "Built-in device tree" 1327 depends on OF && NONPORTABLE 1328 select GENERIC_BUILTIN_DTB 1329 help 1330 Build a device tree into the Linux image. 1331 This option should be selected if no bootloader is being used. 1332 If unsure, say N. 1333 1334 1335config BUILTIN_DTB_NAME 1336 string "Built-in device tree source" 1337 depends on BUILTIN_DTB 1338 help 1339 DTS file path (without suffix, relative to arch/riscv/boot/dts) 1340 for the DTS file that will be used to produce the DTB linked into the 1341 kernel. 1342 1343endmenu # "Boot options" 1344 1345config PORTABLE 1346 bool 1347 default !NONPORTABLE 1348 select EFI 1349 select MMU 1350 select OF 1351 1352config ARCH_PROC_KCORE_TEXT 1353 def_bool y 1354 1355menu "Power management options" 1356 1357source "kernel/power/Kconfig" 1358 1359config ARCH_HIBERNATION_POSSIBLE 1360 def_bool y 1361 1362config ARCH_HIBERNATION_HEADER 1363 def_bool HIBERNATION 1364 1365config ARCH_SUSPEND_POSSIBLE 1366 def_bool y 1367 1368endmenu # "Power management options" 1369 1370menu "CPU Power Management" 1371 1372source "drivers/cpuidle/Kconfig" 1373 1374source "drivers/cpufreq/Kconfig" 1375 1376endmenu # "CPU Power Management" 1377 1378source "arch/riscv/kvm/Kconfig" 1379 1380source "drivers/acpi/Kconfig" 1381