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_PPTT if ACPI 17 select ACPI_REDUCED_HARDWARE_ONLY if ACPI 18 select ACPI_SPCR_TABLE if ACPI 19 select ARCH_DMA_DEFAULT_COHERENT 20 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 21 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM_VMEMMAP 22 select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG 23 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 24 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 25 select ARCH_HAS_BINFMT_FLAT 26 select ARCH_HAS_CURRENT_STACK_POINTER 27 select ARCH_HAS_DEBUG_VIRTUAL if MMU 28 select ARCH_HAS_DEBUG_VM_PGTABLE 29 select ARCH_HAS_DEBUG_WX 30 select ARCH_HAS_FAST_MULTIPLIER 31 select ARCH_HAS_FORTIFY_SOURCE 32 select ARCH_HAS_GCOV_PROFILE_ALL 33 select ARCH_HAS_GIGANTIC_PAGE 34 select ARCH_HAS_KCOV 35 select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU 36 select ARCH_HAS_MEMBARRIER_CALLBACKS 37 select ARCH_HAS_MEMBARRIER_SYNC_CORE 38 select ARCH_HAS_MMIOWB 39 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 40 select ARCH_HAS_PMEM_API 41 select ARCH_HAS_PREPARE_SYNC_CORE_CMD 42 select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU 43 select ARCH_HAS_PTE_SPECIAL 44 select ARCH_HAS_SET_DIRECT_MAP if MMU 45 select ARCH_HAS_SET_MEMORY if MMU 46 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 47 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 48 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 49 select ARCH_HAS_SYSCALL_WRAPPER 50 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 51 select ARCH_HAS_UBSAN 52 select ARCH_HAS_VDSO_DATA 53 select ARCH_KEEP_MEMBLOCK if ACPI 54 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if 64BIT && MMU 55 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 56 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 57 select ARCH_STACKWALK 58 select ARCH_SUPPORTS_ATOMIC_RMW 59 select ARCH_SUPPORTS_CFI_CLANG 60 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 61 select ARCH_SUPPORTS_HUGETLBFS if MMU 62 # LLD >= 14: https://github.com/llvm/llvm-project/issues/50505 63 select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000 64 select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000 65 select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU 66 select ARCH_SUPPORTS_PER_VMA_LOCK if MMU 67 select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK 68 select ARCH_USE_CMPXCHG_LOCKREF if 64BIT 69 select ARCH_USE_MEMTEST 70 select ARCH_USE_QUEUED_RWLOCKS 71 select ARCH_USES_CFI_TRAPS if CFI_CLANG 72 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU 73 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 74 select ARCH_WANT_FRAME_POINTERS 75 select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT 76 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 77 select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL 78 select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP 79 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 80 select ARCH_WANTS_NO_INSTR 81 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 82 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 83 select BUILDTIME_TABLE_SORT if MMU 84 select CLINT_TIMER if RISCV_M_MODE 85 select CLONE_BACKWARDS 86 select COMMON_CLK 87 select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND 88 select EDAC_SUPPORT 89 select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) 90 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE 91 select GENERIC_ARCH_TOPOLOGY 92 select GENERIC_ATOMIC64 if !64BIT 93 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 94 select GENERIC_CPU_DEVICES 95 select GENERIC_CPU_VULNERABILITIES 96 select GENERIC_EARLY_IOREMAP 97 select GENERIC_ENTRY 98 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 99 select GENERIC_IDLE_POLL_SETUP 100 select GENERIC_IOREMAP if MMU 101 select GENERIC_IRQ_IPI if SMP 102 select GENERIC_IRQ_IPI_MUX if SMP 103 select GENERIC_IRQ_MULTI_HANDLER 104 select GENERIC_IRQ_SHOW 105 select GENERIC_IRQ_SHOW_LEVEL 106 select GENERIC_LIB_DEVMEM_IS_ALLOWED 107 select GENERIC_PCI_IOMAP 108 select GENERIC_PTDUMP if MMU 109 select GENERIC_SCHED_CLOCK 110 select GENERIC_SMP_IDLE_THREAD 111 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 112 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 113 select HARDIRQS_SW_RESEND 114 select HAS_IOPORT if MMU 115 select HAVE_ARCH_AUDITSYSCALL 116 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP 117 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT 118 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 119 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 120 select HAVE_ARCH_KASAN if MMU && 64BIT 121 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 122 select HAVE_ARCH_KFENCE if MMU && 64BIT 123 select HAVE_ARCH_KGDB if !XIP_KERNEL 124 select HAVE_ARCH_KGDB_QXFER_PKT 125 select HAVE_ARCH_MMAP_RND_BITS if MMU 126 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 127 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 128 select HAVE_ARCH_SECCOMP_FILTER 129 select HAVE_ARCH_STACKLEAK 130 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 131 select HAVE_ARCH_TRACEHOOK 132 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 133 select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD 134 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 135 select HAVE_ASM_MODVERSIONS 136 select HAVE_CONTEXT_TRACKING_USER 137 select HAVE_DEBUG_KMEMLEAK 138 select HAVE_DMA_CONTIGUOUS if MMU 139 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) 140 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 141 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE 142 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 143 select HAVE_FUNCTION_GRAPH_TRACER 144 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER 145 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION 146 select HAVE_EBPF_JIT if MMU 147 select HAVE_GUP_FAST if MMU 148 select HAVE_FUNCTION_ARG_ACCESS_API 149 select HAVE_FUNCTION_ERROR_INJECTION 150 select HAVE_GCC_PLUGINS 151 select HAVE_GENERIC_VDSO if MMU && 64BIT 152 select HAVE_IRQ_TIME_ACCOUNTING 153 select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT 154 select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT 155 select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT 156 select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT 157 select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT 158 select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT 159 select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT 160 select HAVE_KPROBES if !XIP_KERNEL 161 select HAVE_KRETPROBES if !XIP_KERNEL 162 # https://github.com/ClangBuiltLinux/linux/issues/1881 163 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD 164 select HAVE_MOVE_PMD 165 select HAVE_MOVE_PUD 166 select HAVE_PAGE_SIZE_4KB 167 select HAVE_PCI 168 select HAVE_PERF_EVENTS 169 select HAVE_PERF_REGS 170 select HAVE_PERF_USER_STACK_DUMP 171 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 172 select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL 173 select HAVE_REGS_AND_STACK_ACCESS_API 174 select HAVE_RETHOOK if !XIP_KERNEL 175 select HAVE_RSEQ 176 select HAVE_RUST if 64BIT 177 select HAVE_SAMPLE_FTRACE_DIRECT 178 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 179 select HAVE_STACKPROTECTOR 180 select HAVE_SYSCALL_TRACEPOINTS 181 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 182 select IRQ_DOMAIN 183 select IRQ_FORCED_THREADING 184 select KASAN_VMALLOC if KASAN 185 select LOCK_MM_AND_FIND_VMA 186 select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU 187 select MODULES_USE_ELF_RELA if MODULES 188 select OF 189 select OF_EARLY_FLATTREE 190 select OF_IRQ 191 select PCI_DOMAINS_GENERIC if PCI 192 select PCI_MSI if PCI 193 select RISCV_ALTERNATIVE if !XIP_KERNEL 194 select RISCV_APLIC 195 select RISCV_IMSIC 196 select RISCV_INTC 197 select RISCV_TIMER if RISCV_SBI 198 select SIFIVE_PLIC 199 select SPARSE_IRQ 200 select SYSCTL_EXCEPTION_TRACE 201 select THREAD_INFO_IN_TASK 202 select TRACE_IRQFLAGS_SUPPORT 203 select UACCESS_MEMCPY if !MMU 204 select ZONE_DMA32 if 64BIT 205 206config CLANG_SUPPORTS_DYNAMIC_FTRACE 207 def_bool CC_IS_CLANG 208 # https://github.com/ClangBuiltLinux/linux/issues/1817 209 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 210 211config GCC_SUPPORTS_DYNAMIC_FTRACE 212 def_bool CC_IS_GCC 213 depends on $(cc-option,-fpatchable-function-entry=8) 214 215config HAVE_SHADOW_CALL_STACK 216 def_bool $(cc-option,-fsanitize=shadow-call-stack) 217 # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769 218 depends on $(ld-option,--no-relax-gp) 219 220config RISCV_USE_LINKER_RELAXATION 221 def_bool y 222 # https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985 223 depends on !LD_IS_LLD || LLD_VERSION >= 150000 224 225# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6 226config ARCH_HAS_BROKEN_DWARF5 227 def_bool y 228 depends on RISCV_USE_LINKER_RELAXATION 229 # https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a 230 depends on AS_IS_LLVM && AS_VERSION < 180000 231 # https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77 232 depends on LD_IS_LLD && LLD_VERSION < 180000 233 234config ARCH_MMAP_RND_BITS_MIN 235 default 18 if 64BIT 236 default 8 237 238config ARCH_MMAP_RND_COMPAT_BITS_MIN 239 default 8 240 241# max bits determined by the following formula: 242# VA_BITS - PAGE_SHIFT - 3 243config ARCH_MMAP_RND_BITS_MAX 244 default 24 if 64BIT # SV39 based 245 default 17 246 247config ARCH_MMAP_RND_COMPAT_BITS_MAX 248 default 17 249 250# set if we run in machine mode, cleared if we run in supervisor mode 251config RISCV_M_MODE 252 bool "Build a kernel that runs in machine mode" 253 depends on !MMU 254 default y 255 help 256 Select this option if you want to run the kernel in M-mode, 257 without the assistance of any other firmware. 258 259# set if we are running in S-mode and can use SBI calls 260config RISCV_SBI 261 bool 262 depends on !RISCV_M_MODE 263 default y 264 265config MMU 266 bool "MMU-based Paged Memory Management Support" 267 default y 268 help 269 Select if you want MMU-based virtualised addressing space 270 support by paged memory management. If unsure, say 'Y'. 271 272config PAGE_OFFSET 273 hex 274 default 0x80000000 if !MMU && RISCV_M_MODE 275 default 0x80200000 if !MMU 276 default 0xc0000000 if 32BIT 277 default 0xff60000000000000 if 64BIT 278 279config KASAN_SHADOW_OFFSET 280 hex 281 depends on KASAN_GENERIC 282 default 0xdfffffff00000000 if 64BIT 283 default 0xffffffff if 32BIT 284 285config ARCH_FLATMEM_ENABLE 286 def_bool !NUMA 287 288config ARCH_SPARSEMEM_ENABLE 289 def_bool y 290 depends on MMU 291 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 292 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 293 294config ARCH_SELECT_MEMORY_MODEL 295 def_bool ARCH_SPARSEMEM_ENABLE 296 297config ARCH_SUPPORTS_UPROBES 298 def_bool y 299 300config STACKTRACE_SUPPORT 301 def_bool y 302 303config GENERIC_BUG 304 def_bool y 305 depends on BUG 306 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 307 308config GENERIC_BUG_RELATIVE_POINTERS 309 bool 310 311config GENERIC_CALIBRATE_DELAY 312 def_bool y 313 314config GENERIC_CSUM 315 def_bool y 316 317config GENERIC_HWEIGHT 318 def_bool y 319 320config FIX_EARLYCON_MEM 321 def_bool MMU 322 323config ILLEGAL_POINTER_VALUE 324 hex 325 default 0 if 32BIT 326 default 0xdead000000000000 if 64BIT 327 328config PGTABLE_LEVELS 329 int 330 default 5 if 64BIT 331 default 2 332 333config LOCKDEP_SUPPORT 334 def_bool y 335 336config RISCV_DMA_NONCOHERENT 337 bool 338 select ARCH_HAS_DMA_PREP_COHERENT 339 select ARCH_HAS_SETUP_DMA_OPS 340 select ARCH_HAS_SYNC_DMA_FOR_CPU 341 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 342 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 343 344config RISCV_NONSTANDARD_CACHE_OPS 345 bool 346 help 347 This enables function pointer support for non-standard noncoherent 348 systems to handle cache management. 349 350config AS_HAS_INSN 351 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 352 353config AS_HAS_OPTION_ARCH 354 # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4 355 def_bool y 356 depends on $(as-instr, .option arch$(comma) +m) 357 358source "arch/riscv/Kconfig.socs" 359source "arch/riscv/Kconfig.errata" 360 361menu "Platform type" 362 363config NONPORTABLE 364 bool "Allow configurations that result in non-portable kernels" 365 help 366 RISC-V kernel binaries are compatible between all known systems 367 whenever possible, but there are some use cases that can only be 368 satisfied by configurations that result in kernel binaries that are 369 not portable between systems. 370 371 Selecting N does not guarantee kernels will be portable to all known 372 systems. Selecting any of the options guarded by NONPORTABLE will 373 result in kernel binaries that are unlikely to be portable between 374 systems. 375 376 If unsure, say N. 377 378choice 379 prompt "Base ISA" 380 default ARCH_RV64I 381 help 382 This selects the base ISA that this kernel will target and must match 383 the target platform. 384 385config ARCH_RV32I 386 bool "RV32I" 387 depends on NONPORTABLE 388 select 32BIT 389 select GENERIC_LIB_ASHLDI3 390 select GENERIC_LIB_ASHRDI3 391 select GENERIC_LIB_LSHRDI3 392 select GENERIC_LIB_UCMPDI2 393 394config ARCH_RV64I 395 bool "RV64I" 396 select 64BIT 397 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 398 select SWIOTLB if MMU 399 400endchoice 401 402# We must be able to map all physical memory into the kernel, but the compiler 403# is still a bit more efficient when generating code if it's setup in a manner 404# such that it can only map 2GiB of memory. 405choice 406 prompt "Kernel Code Model" 407 default CMODEL_MEDLOW if 32BIT 408 default CMODEL_MEDANY if 64BIT 409 410 config CMODEL_MEDLOW 411 bool "medium low code model" 412 config CMODEL_MEDANY 413 bool "medium any code model" 414endchoice 415 416config MODULE_SECTIONS 417 bool 418 select HAVE_MOD_ARCH_SPECIFIC 419 420config SMP 421 bool "Symmetric Multi-Processing" 422 help 423 This enables support for systems with more than one CPU. If 424 you say N here, the kernel will run on single and 425 multiprocessor machines, but will use only one CPU of a 426 multiprocessor machine. If you say Y here, the kernel will run 427 on many, but not all, single processor machines. On a single 428 processor machine, the kernel will run faster if you say N 429 here. 430 431 If you don't know what to do here, say N. 432 433config SCHED_MC 434 bool "Multi-core scheduler support" 435 depends on SMP 436 help 437 Multi-core scheduler support improves the CPU scheduler's decision 438 making when dealing with multi-core CPU chips at a cost of slightly 439 increased overhead in some places. If unsure say N here. 440 441config NR_CPUS 442 int "Maximum number of CPUs (2-512)" 443 depends on SMP 444 range 2 512 if !RISCV_SBI_V01 445 range 2 32 if RISCV_SBI_V01 && 32BIT 446 range 2 64 if RISCV_SBI_V01 && 64BIT 447 default "32" if 32BIT 448 default "64" if 64BIT 449 450config HOTPLUG_CPU 451 bool "Support for hot-pluggable CPUs" 452 depends on SMP 453 select GENERIC_IRQ_MIGRATION 454 help 455 456 Say Y here to experiment with turning CPUs off and on. CPUs 457 can be controlled through /sys/devices/system/cpu. 458 459 Say N if you want to disable CPU hotplug. 460 461choice 462 prompt "CPU Tuning" 463 default TUNE_GENERIC 464 465config TUNE_GENERIC 466 bool "generic" 467 468endchoice 469 470# Common NUMA Features 471config NUMA 472 bool "NUMA Memory Allocation and Scheduler Support" 473 depends on SMP && MMU 474 select ARCH_SUPPORTS_NUMA_BALANCING 475 select GENERIC_ARCH_NUMA 476 select HAVE_SETUP_PER_CPU_AREA 477 select NEED_PER_CPU_EMBED_FIRST_CHUNK 478 select NEED_PER_CPU_PAGE_FIRST_CHUNK 479 select OF_NUMA 480 select USE_PERCPU_NUMA_NODE_ID 481 help 482 Enable NUMA (Non-Uniform Memory Access) support. 483 484 The kernel will try to allocate memory used by a CPU on the 485 local memory of the CPU and add some more NUMA awareness to the kernel. 486 487config NODES_SHIFT 488 int "Maximum NUMA Nodes (as a power of 2)" 489 range 1 10 490 default "2" 491 depends on NUMA 492 help 493 Specify the maximum number of NUMA Nodes available on the target 494 system. Increases memory reserved to accommodate various tables. 495 496config RISCV_ALTERNATIVE 497 bool 498 depends on !XIP_KERNEL 499 help 500 This Kconfig allows the kernel to automatically patch the 501 erratum or cpufeature required by the execution platform at run 502 time. The code patching overhead is minimal, as it's only done 503 once at boot and once on each module load. 504 505config RISCV_ALTERNATIVE_EARLY 506 bool 507 depends on RISCV_ALTERNATIVE 508 help 509 Allows early patching of the kernel for special errata 510 511config RISCV_ISA_C 512 bool "Emit compressed instructions when building Linux" 513 default y 514 help 515 Adds "C" to the ISA subsets that the toolchain is allowed to emit 516 when building Linux, which results in compressed instructions in the 517 Linux binary. 518 519 If you don't know what to do here, say Y. 520 521config RISCV_ISA_SVNAPOT 522 bool "Svnapot extension support for supervisor mode NAPOT pages" 523 depends on 64BIT && MMU 524 depends on RISCV_ALTERNATIVE 525 default y 526 help 527 Allow kernel to detect the Svnapot ISA-extension dynamically at boot 528 time and enable its usage. 529 530 The Svnapot extension is used to mark contiguous PTEs as a range 531 of contiguous virtual-to-physical translations for a naturally 532 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 533 size. When HUGETLBFS is also selected this option unconditionally 534 allocates some memory for each NAPOT page size supported by the kernel. 535 When optimizing for low memory consumption and for platforms without 536 the Svnapot extension, it may be better to say N here. 537 538 If you don't know what to do here, say Y. 539 540config RISCV_ISA_SVPBMT 541 bool "Svpbmt extension support for supervisor mode page-based memory types" 542 depends on 64BIT && MMU 543 depends on RISCV_ALTERNATIVE 544 default y 545 help 546 Adds support to dynamically detect the presence of the Svpbmt 547 ISA-extension (Supervisor-mode: page-based memory types) and 548 enable its usage. 549 550 The memory type for a page contains a combination of attributes 551 that indicate the cacheability, idempotency, and ordering 552 properties for access to that page. 553 554 The Svpbmt extension is only available on 64-bit cpus. 555 556 If you don't know what to do here, say Y. 557 558config TOOLCHAIN_HAS_V 559 bool 560 default y 561 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64iv) 562 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32iv) 563 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 564 depends on AS_HAS_OPTION_ARCH 565 566config RISCV_ISA_V 567 bool "VECTOR extension support" 568 depends on TOOLCHAIN_HAS_V 569 depends on FPU 570 select DYNAMIC_SIGFRAME 571 default y 572 help 573 Say N here if you want to disable all vector related procedure 574 in the kernel. 575 576 If you don't know what to do here, say Y. 577 578config RISCV_ISA_V_DEFAULT_ENABLE 579 bool "Enable userspace Vector by default" 580 depends on RISCV_ISA_V 581 default y 582 help 583 Say Y here if you want to enable Vector in userspace by default. 584 Otherwise, userspace has to make explicit prctl() call to enable 585 Vector, or enable it via the sysctl interface. 586 587 If you don't know what to do here, say Y. 588 589config RISCV_ISA_V_UCOPY_THRESHOLD 590 int "Threshold size for vectorized user copies" 591 depends on RISCV_ISA_V 592 default 768 593 help 594 Prefer using vectorized copy_to_user()/copy_from_user() when the 595 workload size exceeds this value. 596 597config RISCV_ISA_V_PREEMPTIVE 598 bool "Run kernel-mode Vector with kernel preemption" 599 depends on PREEMPTION 600 depends on RISCV_ISA_V 601 default y 602 help 603 Usually, in-kernel SIMD routines are run with preemption disabled. 604 Functions which envoke long running SIMD thus must yield core's 605 vector unit to prevent blocking other tasks for too long. 606 607 This config allows kernel to run SIMD without explicitly disable 608 preemption. Enabling this config will result in higher memory 609 consumption due to the allocation of per-task's kernel Vector context. 610 611config RISCV_ISA_ZAWRS 612 bool "Zawrs extension support for more efficient busy waiting" 613 depends on RISCV_ALTERNATIVE 614 default y 615 help 616 The Zawrs extension defines instructions to be used in polling loops 617 which allow a hart to enter a low-power state or to trap to the 618 hypervisor while waiting on a store to a memory location. Enable the 619 use of these instructions in the kernel when the Zawrs extension is 620 detected at boot. 621 622 If you don't know what to do here, say Y. 623 624config TOOLCHAIN_HAS_ZBB 625 bool 626 default y 627 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 628 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 629 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 630 depends on AS_HAS_OPTION_ARCH 631 632# This symbol indicates that the toolchain supports all v1.0 vector crypto 633# extensions, including Zvk*, Zvbb, and Zvbc. LLVM added all of these at once. 634# binutils added all except Zvkb, then added Zvkb. So we just check for Zvkb. 635config TOOLCHAIN_HAS_VECTOR_CRYPTO 636 def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb) 637 depends on AS_HAS_OPTION_ARCH 638 639config RISCV_ISA_ZBA 640 bool "Zba extension support for bit manipulation instructions" 641 default y 642 help 643 Add support for enabling optimisations in the kernel when the Zba 644 extension is detected at boot. 645 646 The Zba extension provides instructions to accelerate the generation 647 of addresses that index into arrays of basic data types. 648 649 If you don't know what to do here, say Y. 650 651config RISCV_ISA_ZBB 652 bool "Zbb extension support for bit manipulation instructions" 653 depends on TOOLCHAIN_HAS_ZBB 654 depends on RISCV_ALTERNATIVE 655 default y 656 help 657 Adds support to dynamically detect the presence of the ZBB 658 extension (basic bit manipulation) and enable its usage. 659 660 The Zbb extension provides instructions to accelerate a number 661 of bit-specific operations (count bit population, sign extending, 662 bitrotation, etc). 663 664 If you don't know what to do here, say Y. 665 666config TOOLCHAIN_HAS_ZBC 667 bool 668 default y 669 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc) 670 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc) 671 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 672 depends on AS_HAS_OPTION_ARCH 673 674config RISCV_ISA_ZBC 675 bool "Zbc extension support for carry-less multiplication instructions" 676 depends on TOOLCHAIN_HAS_ZBC 677 depends on MMU 678 depends on RISCV_ALTERNATIVE 679 default y 680 help 681 Adds support to dynamically detect the presence of the Zbc 682 extension (carry-less multiplication) and enable its usage. 683 684 The Zbc extension could accelerate CRC (cyclic redundancy check) 685 calculations. 686 687 If you don't know what to do here, say Y. 688 689config RISCV_ISA_ZICBOM 690 bool "Zicbom extension support for non-coherent DMA operation" 691 depends on MMU 692 depends on RISCV_ALTERNATIVE 693 default y 694 select RISCV_DMA_NONCOHERENT 695 select DMA_DIRECT_REMAP 696 help 697 Adds support to dynamically detect the presence of the ZICBOM 698 extension (Cache Block Management Operations) and enable its 699 usage. 700 701 The Zicbom extension can be used to handle for example 702 non-coherent DMA support on devices that need it. 703 704 If you don't know what to do here, say Y. 705 706config RISCV_ISA_ZICBOZ 707 bool "Zicboz extension support for faster zeroing of memory" 708 depends on RISCV_ALTERNATIVE 709 default y 710 help 711 Enable the use of the Zicboz extension (cbo.zero instruction) 712 when available. 713 714 The Zicboz extension is used for faster zeroing of memory. 715 716 If you don't know what to do here, say Y. 717 718config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 719 def_bool y 720 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 721 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 722 depends on AS_IS_GNU && AS_VERSION >= 23600 723 help 724 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 725 20191213 version, which moves some instructions from the I extension to 726 the Zicsr and Zifencei extensions. This requires explicitly specifying 727 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 728 and Zifencei are supported in binutils from version 2.36 onwards. 729 To make life easier, and avoid forcing toolchains that default to a 730 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 731 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 732 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 733 734config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 735 def_bool y 736 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 737 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 738 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 739 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 740 help 741 Certain versions of clang and GCC do not support zicsr and zifencei via 742 -march. This option causes an older ISA spec compatible with these older 743 versions of clang and GCC to be passed to GAS, which has the same result 744 as passing zicsr and zifencei to -march. 745 746config FPU 747 bool "FPU support" 748 default y 749 help 750 Say N here if you want to disable all floating-point related procedure 751 in the kernel. 752 753 If you don't know what to do here, say Y. 754 755config IRQ_STACKS 756 bool "Independent irq & softirq stacks" if EXPERT 757 default y 758 select HAVE_IRQ_EXIT_ON_IRQ_STACK 759 select HAVE_SOFTIRQ_ON_OWN_STACK 760 help 761 Add independent irq & softirq stacks for percpu to prevent kernel stack 762 overflows. We may save some memory footprint by disabling IRQ_STACKS. 763 764config THREAD_SIZE_ORDER 765 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 766 range 0 4 767 default 1 if 32BIT && !KASAN 768 default 3 if 64BIT && KASAN 769 default 2 770 help 771 Specify the Pages of thread stack size (from 4KB to 64KB), which also 772 affects irq stack size, which is equal to thread stack size. 773 774config RISCV_MISALIGNED 775 bool 776 select SYSCTL_ARCH_UNALIGN_ALLOW 777 help 778 Embed support for emulating misaligned loads and stores. 779 780choice 781 prompt "Unaligned Accesses Support" 782 default RISCV_PROBE_UNALIGNED_ACCESS 783 help 784 This determines the level of support for unaligned accesses. This 785 information is used by the kernel to perform optimizations. It is also 786 exposed to user space via the hwprobe syscall. The hardware will be 787 probed at boot by default. 788 789config RISCV_PROBE_UNALIGNED_ACCESS 790 bool "Probe for hardware unaligned access support" 791 select RISCV_MISALIGNED 792 help 793 During boot, the kernel will run a series of tests to determine the 794 speed of unaligned accesses. This probing will dynamically determine 795 the speed of unaligned accesses on the underlying system. If unaligned 796 memory accesses trap into the kernel as they are not supported by the 797 system, the kernel will emulate the unaligned accesses to preserve the 798 UABI. 799 800config RISCV_EMULATED_UNALIGNED_ACCESS 801 bool "Emulate unaligned access where system support is missing" 802 select RISCV_MISALIGNED 803 help 804 If unaligned memory accesses trap into the kernel as they are not 805 supported by the system, the kernel will emulate the unaligned 806 accesses to preserve the UABI. When the underlying system does support 807 unaligned accesses, the unaligned accesses are assumed to be slow. 808 809config RISCV_SLOW_UNALIGNED_ACCESS 810 bool "Assume the system supports slow unaligned memory accesses" 811 depends on NONPORTABLE 812 help 813 Assume that the system supports slow unaligned memory accesses. The 814 kernel and userspace programs may not be able to run at all on systems 815 that do not support unaligned memory accesses. 816 817config RISCV_EFFICIENT_UNALIGNED_ACCESS 818 bool "Assume the system supports fast unaligned memory accesses" 819 depends on NONPORTABLE 820 select DCACHE_WORD_ACCESS if MMU 821 select HAVE_EFFICIENT_UNALIGNED_ACCESS 822 help 823 Assume that the system supports fast unaligned memory accesses. When 824 enabled, this option improves the performance of the kernel on such 825 systems. However, the kernel and userspace programs will run much more 826 slowly, or will not be able to run at all, on systems that do not 827 support efficient unaligned memory accesses. 828 829endchoice 830 831source "arch/riscv/Kconfig.vendor" 832 833endmenu # "Platform type" 834 835menu "Kernel features" 836 837source "kernel/Kconfig.hz" 838 839config RISCV_SBI_V01 840 bool "SBI v0.1 support" 841 depends on RISCV_SBI 842 help 843 This config allows kernel to use SBI v0.1 APIs. This will be 844 deprecated in future once legacy M-mode software are no longer in use. 845 846config RISCV_BOOT_SPINWAIT 847 bool "Spinwait booting method" 848 depends on SMP 849 default y if RISCV_SBI_V01 || RISCV_M_MODE 850 help 851 This enables support for booting Linux via spinwait method. In the 852 spinwait method, all cores randomly jump to Linux. One of the cores 853 gets chosen via lottery and all other keep spinning on a percpu 854 variable. This method cannot support CPU hotplug and sparse hartid 855 scheme. It should be only enabled for M-mode Linux or platforms relying 856 on older firmware without SBI HSM extension. All other platforms should 857 rely on ordered booting via SBI HSM extension which gets chosen 858 dynamically at runtime if the firmware supports it. 859 860 Since spinwait is incompatible with sparse hart IDs, it requires 861 NR_CPUS be large enough to contain the physical hart ID of the first 862 hart to enter Linux. 863 864 If unsure what to do here, say N. 865 866config ARCH_SUPPORTS_KEXEC 867 def_bool y 868 869config ARCH_SELECTS_KEXEC 870 def_bool y 871 depends on KEXEC 872 select HOTPLUG_CPU if SMP 873 874config ARCH_SUPPORTS_KEXEC_FILE 875 def_bool 64BIT 876 877config ARCH_SELECTS_KEXEC_FILE 878 def_bool y 879 depends on KEXEC_FILE 880 select HAVE_IMA_KEXEC if IMA 881 select KEXEC_ELF 882 883config ARCH_SUPPORTS_KEXEC_PURGATORY 884 def_bool ARCH_SUPPORTS_KEXEC_FILE 885 886config ARCH_SUPPORTS_CRASH_DUMP 887 def_bool y 888 889config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 890 def_bool CRASH_RESERVE 891 892config COMPAT 893 bool "Kernel support for 32-bit U-mode" 894 default 64BIT 895 depends on 64BIT && MMU 896 help 897 This option enables support for a 32-bit U-mode running under a 64-bit 898 kernel at S-mode. riscv32-specific components such as system calls, 899 the user helper functions (vdso), signal rt_frame functions and the 900 ptrace interface are handled appropriately by the kernel. 901 902 If you want to execute 32-bit userspace applications, say Y. 903 904config PARAVIRT 905 bool "Enable paravirtualization code" 906 depends on RISCV_SBI 907 help 908 This changes the kernel so it can modify itself when it is run 909 under a hypervisor, potentially improving performance significantly 910 over full virtualization. 911 912config PARAVIRT_TIME_ACCOUNTING 913 bool "Paravirtual steal time accounting" 914 depends on PARAVIRT 915 help 916 Select this option to enable fine granularity task steal time 917 accounting. Time spent executing other tasks in parallel with 918 the current vCPU is discounted from the vCPU power. To account for 919 that, there can be a small performance impact. 920 921 If in doubt, say N here. 922 923config RELOCATABLE 924 bool "Build a relocatable kernel" 925 depends on MMU && 64BIT && !XIP_KERNEL 926 select MODULE_SECTIONS if MODULES 927 help 928 This builds a kernel as a Position Independent Executable (PIE), 929 which retains all relocation metadata required to relocate the 930 kernel binary at runtime to a different virtual address than the 931 address it was linked at. 932 Since RISCV uses the RELA relocation format, this requires a 933 relocation pass at runtime even if the kernel is loaded at the 934 same address it was linked at. 935 936 If unsure, say N. 937 938config RANDOMIZE_BASE 939 bool "Randomize the address of the kernel image" 940 select RELOCATABLE 941 depends on MMU && 64BIT && !XIP_KERNEL 942 help 943 Randomizes the virtual address at which the kernel image is 944 loaded, as a security feature that deters exploit attempts 945 relying on knowledge of the location of kernel internals. 946 947 It is the bootloader's job to provide entropy, by passing a 948 random u64 value in /chosen/kaslr-seed at kernel entry. 949 950 When booting via the UEFI stub, it will invoke the firmware's 951 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 952 to the kernel proper. In addition, it will randomise the physical 953 location of the kernel Image as well. 954 955 If unsure, say N. 956 957endmenu # "Kernel features" 958 959menu "Boot options" 960 961config CMDLINE 962 string "Built-in kernel command line" 963 help 964 For most platforms, the arguments for the kernel's command line 965 are provided at run-time, during boot. However, there are cases 966 where either no arguments are being provided or the provided 967 arguments are insufficient or even invalid. 968 969 When that occurs, it is possible to define a built-in command 970 line here and choose how the kernel should use it later on. 971 972choice 973 prompt "Built-in command line usage" 974 depends on CMDLINE != "" 975 default CMDLINE_FALLBACK 976 help 977 Choose how the kernel will handle the provided built-in command 978 line. 979 980config CMDLINE_FALLBACK 981 bool "Use bootloader kernel arguments if available" 982 help 983 Use the built-in command line as fallback in case we get nothing 984 during boot. This is the default behaviour. 985 986config CMDLINE_EXTEND 987 bool "Extend bootloader kernel arguments" 988 help 989 The command-line arguments provided during boot will be 990 appended to the built-in command line. This is useful in 991 cases where the provided arguments are insufficient and 992 you don't want to or cannot modify them. 993 994config CMDLINE_FORCE 995 bool "Always use the default kernel command string" 996 help 997 Always use the built-in command line, even if we get one during 998 boot. This is useful in case you need to override the provided 999 command line on systems where you don't have or want control 1000 over it. 1001 1002endchoice 1003 1004config EFI_STUB 1005 bool 1006 1007config EFI 1008 bool "UEFI runtime support" 1009 depends on OF && !XIP_KERNEL 1010 depends on MMU 1011 default y 1012 select ARCH_SUPPORTS_ACPI if 64BIT 1013 select EFI_GENERIC_STUB 1014 select EFI_PARAMS_FROM_FDT 1015 select EFI_RUNTIME_WRAPPERS 1016 select EFI_STUB 1017 select LIBFDT 1018 select RISCV_ISA_C 1019 select UCS2_STRING 1020 help 1021 This option provides support for runtime services provided 1022 by UEFI firmware (such as non-volatile variables, realtime 1023 clock, and platform reset). A UEFI stub is also provided to 1024 allow the kernel to be booted as an EFI application. This 1025 is only useful on systems that have UEFI firmware. 1026 1027config DMI 1028 bool "Enable support for SMBIOS (DMI) tables" 1029 depends on EFI 1030 default y 1031 help 1032 This enables SMBIOS/DMI feature for systems. 1033 1034 This option is only useful on systems that have UEFI firmware. 1035 However, even with this option, the resultant kernel should 1036 continue to boot on existing non-UEFI platforms. 1037 1038config CC_HAVE_STACKPROTECTOR_TLS 1039 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 1040 1041config STACKPROTECTOR_PER_TASK 1042 def_bool y 1043 depends on !RANDSTRUCT 1044 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 1045 1046config PHYS_RAM_BASE_FIXED 1047 bool "Explicitly specified physical RAM address" 1048 depends on NONPORTABLE 1049 default n 1050 1051config PHYS_RAM_BASE 1052 hex "Platform Physical RAM address" 1053 depends on PHYS_RAM_BASE_FIXED 1054 default "0x80000000" 1055 help 1056 This is the physical address of RAM in the system. It has to be 1057 explicitly specified to run early relocations of read-write data 1058 from flash to RAM. 1059 1060config XIP_KERNEL 1061 bool "Kernel Execute-In-Place from ROM" 1062 depends on MMU && SPARSEMEM && NONPORTABLE 1063 # This prevents XIP from being enabled by all{yes,mod}config, which 1064 # fail to build since XIP doesn't support large kernels. 1065 depends on !COMPILE_TEST 1066 select PHYS_RAM_BASE_FIXED 1067 help 1068 Execute-In-Place allows the kernel to run from non-volatile storage 1069 directly addressable by the CPU, such as NOR flash. This saves RAM 1070 space since the text section of the kernel is not loaded from flash 1071 to RAM. Read-write sections, such as the data section and stack, 1072 are still copied to RAM. The XIP kernel is not compressed since 1073 it has to run directly from flash, so it will take more space to 1074 store it. The flash address used to link the kernel object files, 1075 and for storing it, is configuration dependent. Therefore, if you 1076 say Y here, you must know the proper physical address where to 1077 store the kernel image depending on your own flash memory usage. 1078 1079 Also note that the make target becomes "make xipImage" rather than 1080 "make zImage" or "make Image". The final kernel binary to put in 1081 ROM memory will be arch/riscv/boot/xipImage. 1082 1083 SPARSEMEM is required because the kernel text and rodata that are 1084 flash resident are not backed by memmap, then any attempt to get 1085 a struct page on those regions will trigger a fault. 1086 1087 If unsure, say N. 1088 1089config XIP_PHYS_ADDR 1090 hex "XIP Kernel Physical Location" 1091 depends on XIP_KERNEL 1092 default "0x21000000" 1093 help 1094 This is the physical address in your flash memory the kernel will 1095 be linked for and stored to. This address is dependent on your 1096 own flash usage. 1097 1098config RISCV_ISA_FALLBACK 1099 bool "Permit falling back to parsing riscv,isa for extension support by default" 1100 default y 1101 help 1102 Parsing the "riscv,isa" devicetree property has been deprecated and 1103 replaced by a list of explicitly defined strings. For compatibility 1104 with existing platforms, the kernel will fall back to parsing the 1105 "riscv,isa" property if the replacements are not found. 1106 1107 Selecting N here will result in a kernel that does not use the 1108 fallback, unless the commandline "riscv_isa_fallback" parameter is 1109 present. 1110 1111 Please see the dt-binding, located at 1112 Documentation/devicetree/bindings/riscv/extensions.yaml for details 1113 on the replacement properties, "riscv,isa-base" and 1114 "riscv,isa-extensions". 1115 1116config BUILTIN_DTB 1117 bool "Built-in device tree" 1118 depends on OF && NONPORTABLE 1119 help 1120 Build a device tree into the Linux image. 1121 This option should be selected if no bootloader is being used. 1122 If unsure, say N. 1123 1124 1125config BUILTIN_DTB_SOURCE 1126 string "Built-in device tree source" 1127 depends on BUILTIN_DTB 1128 help 1129 DTS file path (without suffix, relative to arch/riscv/boot/dts) 1130 for the DTS file that will be used to produce the DTB linked into the 1131 kernel. 1132 1133endmenu # "Boot options" 1134 1135config PORTABLE 1136 bool 1137 default !NONPORTABLE 1138 select EFI 1139 select MMU 1140 select OF 1141 1142config ARCH_PROC_KCORE_TEXT 1143 def_bool y 1144 1145menu "Power management options" 1146 1147source "kernel/power/Kconfig" 1148 1149config ARCH_HIBERNATION_POSSIBLE 1150 def_bool y 1151 1152config ARCH_HIBERNATION_HEADER 1153 def_bool HIBERNATION 1154 1155config ARCH_SUSPEND_POSSIBLE 1156 def_bool y 1157 1158endmenu # "Power management options" 1159 1160menu "CPU Power Management" 1161 1162source "drivers/cpuidle/Kconfig" 1163 1164source "drivers/cpufreq/Kconfig" 1165 1166endmenu # "CPU Power Management" 1167 1168source "arch/riscv/kvm/Kconfig" 1169 1170source "drivers/acpi/Kconfig" 1171