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_CURRENT_STACK_POINTER 28 select ARCH_HAS_DEBUG_VIRTUAL if MMU 29 select ARCH_HAS_DEBUG_VM_PGTABLE 30 select ARCH_HAS_DEBUG_WX 31 select ARCH_HAS_FAST_MULTIPLIER 32 select ARCH_HAS_FORTIFY_SOURCE 33 select ARCH_HAS_GCOV_PROFILE_ALL 34 select ARCH_HAS_GIGANTIC_PAGE 35 select ARCH_HAS_KCOV 36 select ARCH_HAS_KERNEL_FPU_SUPPORT if 64BIT && FPU 37 select ARCH_HAS_MEMBARRIER_CALLBACKS 38 select ARCH_HAS_MEMBARRIER_SYNC_CORE 39 select ARCH_HAS_MMIOWB 40 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 41 select ARCH_HAS_PMEM_API 42 select ARCH_HAS_PREPARE_SYNC_CORE_CMD 43 select ARCH_HAS_PTE_DEVMAP if 64BIT && MMU 44 select ARCH_HAS_PTE_SPECIAL 45 select ARCH_HAS_SET_DIRECT_MAP if MMU 46 select ARCH_HAS_SET_MEMORY if MMU 47 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 48 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 49 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 50 select ARCH_HAS_SYSCALL_WRAPPER 51 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 52 select ARCH_HAS_UBSAN 53 select ARCH_HAS_VDSO_DATA 54 select ARCH_KEEP_MEMBLOCK if ACPI 55 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE if 64BIT && MMU 56 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 57 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 58 select ARCH_STACKWALK 59 select ARCH_SUPPORTS_ATOMIC_RMW 60 select ARCH_SUPPORTS_CFI_CLANG 61 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 62 select ARCH_SUPPORTS_HUGETLBFS if MMU 63 # LLD >= 14: https://github.com/llvm/llvm-project/issues/50505 64 select ARCH_SUPPORTS_LTO_CLANG if LLD_VERSION >= 140000 65 select ARCH_SUPPORTS_LTO_CLANG_THIN if LLD_VERSION >= 140000 66 select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU 67 select ARCH_SUPPORTS_PER_VMA_LOCK if MMU 68 select ARCH_SUPPORTS_RT 69 select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK 70 select ARCH_USE_CMPXCHG_LOCKREF if 64BIT 71 select ARCH_USE_MEMTEST 72 select ARCH_USE_QUEUED_RWLOCKS 73 select ARCH_USES_CFI_TRAPS if CFI_CLANG 74 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU 75 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 76 select ARCH_WANT_FRAME_POINTERS 77 select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT 78 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 79 select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL 80 select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP 81 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 82 select ARCH_WANTS_NO_INSTR 83 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 84 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 85 select BUILDTIME_TABLE_SORT if MMU 86 select CLINT_TIMER if RISCV_M_MODE 87 select CLONE_BACKWARDS 88 select COMMON_CLK 89 select CPU_PM if CPU_IDLE || HIBERNATION || SUSPEND 90 select EDAC_SUPPORT 91 select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) 92 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY if DYNAMIC_FTRACE 93 select GENERIC_ARCH_TOPOLOGY 94 select GENERIC_ATOMIC64 if !64BIT 95 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 96 select GENERIC_CPU_DEVICES 97 select GENERIC_EARLY_IOREMAP 98 select GENERIC_ENTRY 99 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 100 select GENERIC_IDLE_POLL_SETUP 101 select GENERIC_IOREMAP if MMU 102 select GENERIC_IRQ_IPI if SMP 103 select GENERIC_IRQ_IPI_MUX if SMP 104 select GENERIC_IRQ_MULTI_HANDLER 105 select GENERIC_IRQ_SHOW 106 select GENERIC_IRQ_SHOW_LEVEL 107 select GENERIC_LIB_DEVMEM_IS_ALLOWED 108 select GENERIC_PCI_IOMAP 109 select GENERIC_PTDUMP if MMU 110 select GENERIC_SCHED_CLOCK 111 select GENERIC_SMP_IDLE_THREAD 112 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 113 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 114 select HARDIRQS_SW_RESEND 115 select HAS_IOPORT if MMU 116 select HAVE_ARCH_AUDITSYSCALL 117 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP 118 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT 119 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 120 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 121 select HAVE_ARCH_KASAN if MMU && 64BIT 122 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 123 select HAVE_ARCH_KFENCE if MMU && 64BIT 124 select HAVE_ARCH_KGDB if !XIP_KERNEL 125 select HAVE_ARCH_KGDB_QXFER_PKT 126 select HAVE_ARCH_MMAP_RND_BITS if MMU 127 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 128 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 129 select HAVE_ARCH_SECCOMP_FILTER 130 select HAVE_ARCH_STACKLEAK 131 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 132 select HAVE_ARCH_TRACEHOOK 133 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 134 select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD 135 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 136 select HAVE_ASM_MODVERSIONS 137 select HAVE_CONTEXT_TRACKING_USER 138 select HAVE_DEBUG_KMEMLEAK 139 select HAVE_DMA_CONTIGUOUS if MMU 140 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) 141 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS 142 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE 143 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 144 select HAVE_FUNCTION_GRAPH_TRACER 145 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER 146 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION 147 select HAVE_EBPF_JIT if MMU 148 select HAVE_GUP_FAST if MMU 149 select HAVE_FUNCTION_ARG_ACCESS_API 150 select HAVE_FUNCTION_ERROR_INJECTION 151 select HAVE_GCC_PLUGINS 152 select HAVE_GENERIC_VDSO if MMU && 64BIT 153 select HAVE_IRQ_TIME_ACCOUNTING 154 select HAVE_KERNEL_BZIP2 if !XIP_KERNEL && !EFI_ZBOOT 155 select HAVE_KERNEL_GZIP if !XIP_KERNEL && !EFI_ZBOOT 156 select HAVE_KERNEL_LZ4 if !XIP_KERNEL && !EFI_ZBOOT 157 select HAVE_KERNEL_LZMA if !XIP_KERNEL && !EFI_ZBOOT 158 select HAVE_KERNEL_LZO if !XIP_KERNEL && !EFI_ZBOOT 159 select HAVE_KERNEL_UNCOMPRESSED if !XIP_KERNEL && !EFI_ZBOOT 160 select HAVE_KERNEL_ZSTD if !XIP_KERNEL && !EFI_ZBOOT 161 select HAVE_KERNEL_XZ if !XIP_KERNEL && !EFI_ZBOOT 162 select HAVE_KPROBES if !XIP_KERNEL 163 select HAVE_KRETPROBES if !XIP_KERNEL 164 # https://github.com/ClangBuiltLinux/linux/issues/1881 165 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD 166 select HAVE_MOVE_PMD 167 select HAVE_MOVE_PUD 168 select HAVE_PAGE_SIZE_4KB 169 select HAVE_PCI 170 select HAVE_PERF_EVENTS 171 select HAVE_PERF_REGS 172 select HAVE_PERF_USER_STACK_DUMP 173 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 174 select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL 175 select HAVE_REGS_AND_STACK_ACCESS_API 176 select HAVE_RETHOOK if !XIP_KERNEL 177 select HAVE_RSEQ 178 select HAVE_RUST if 64BIT 179 select HAVE_SAMPLE_FTRACE_DIRECT 180 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 181 select HAVE_STACKPROTECTOR 182 select HAVE_SYSCALL_TRACEPOINTS 183 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 184 select IRQ_DOMAIN 185 select IRQ_FORCED_THREADING 186 select KASAN_VMALLOC if KASAN 187 select LOCK_MM_AND_FIND_VMA 188 select MMU_GATHER_RCU_TABLE_FREE if SMP && MMU 189 select MODULES_USE_ELF_RELA if MODULES 190 select OF 191 select OF_EARLY_FLATTREE 192 select OF_IRQ 193 select PCI_DOMAINS_GENERIC if PCI 194 select PCI_ECAM if (ACPI && PCI) 195 select PCI_MSI if PCI 196 select RISCV_ALTERNATIVE if !XIP_KERNEL 197 select RISCV_APLIC 198 select RISCV_IMSIC 199 select RISCV_INTC 200 select RISCV_TIMER if RISCV_SBI 201 select SIFIVE_PLIC 202 select SPARSE_IRQ 203 select SYSCTL_EXCEPTION_TRACE 204 select THREAD_INFO_IN_TASK 205 select TRACE_IRQFLAGS_SUPPORT 206 select UACCESS_MEMCPY if !MMU 207 select ZONE_DMA32 if 64BIT 208 209config CLANG_SUPPORTS_DYNAMIC_FTRACE 210 def_bool CC_IS_CLANG 211 # https://github.com/ClangBuiltLinux/linux/issues/1817 212 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 213 214config GCC_SUPPORTS_DYNAMIC_FTRACE 215 def_bool CC_IS_GCC 216 depends on $(cc-option,-fpatchable-function-entry=8) 217 218config HAVE_SHADOW_CALL_STACK 219 def_bool $(cc-option,-fsanitize=shadow-call-stack) 220 # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769 221 depends on $(ld-option,--no-relax-gp) 222 223config RISCV_USE_LINKER_RELAXATION 224 def_bool y 225 # https://github.com/llvm/llvm-project/commit/6611d58f5bbcbec77262d392e2923e1d680f6985 226 depends on !LD_IS_LLD || LLD_VERSION >= 150000 227 228# https://github.com/llvm/llvm-project/commit/bbc0f99f3bc96f1db16f649fc21dd18e5b0918f6 229config ARCH_HAS_BROKEN_DWARF5 230 def_bool y 231 depends on RISCV_USE_LINKER_RELAXATION 232 # https://github.com/llvm/llvm-project/commit/1df5ea29b43690b6622db2cad7b745607ca4de6a 233 depends on AS_IS_LLVM && AS_VERSION < 180000 234 # https://github.com/llvm/llvm-project/commit/7ffabb61a5569444b5ac9322e22e5471cc5e4a77 235 depends on LD_IS_LLD && LLD_VERSION < 180000 236 237config ARCH_MMAP_RND_BITS_MIN 238 default 18 if 64BIT 239 default 8 240 241config ARCH_MMAP_RND_COMPAT_BITS_MIN 242 default 8 243 244# max bits determined by the following formula: 245# VA_BITS - PAGE_SHIFT - 3 246config ARCH_MMAP_RND_BITS_MAX 247 default 24 if 64BIT # SV39 based 248 default 17 249 250config ARCH_MMAP_RND_COMPAT_BITS_MAX 251 default 17 252 253# set if we run in machine mode, cleared if we run in supervisor mode 254config RISCV_M_MODE 255 bool "Build a kernel that runs in machine mode" 256 depends on !MMU 257 default y 258 help 259 Select this option if you want to run the kernel in M-mode, 260 without the assistance of any other firmware. 261 262# set if we are running in S-mode and can use SBI calls 263config RISCV_SBI 264 bool 265 depends on !RISCV_M_MODE 266 default y 267 268config MMU 269 bool "MMU-based Paged Memory Management Support" 270 default y 271 help 272 Select if you want MMU-based virtualised addressing space 273 support by paged memory management. If unsure, say 'Y'. 274 275config PAGE_OFFSET 276 hex 277 default 0x80000000 if !MMU && RISCV_M_MODE 278 default 0x80200000 if !MMU 279 default 0xc0000000 if 32BIT 280 default 0xff60000000000000 if 64BIT 281 282config KASAN_SHADOW_OFFSET 283 hex 284 depends on KASAN_GENERIC 285 default 0xdfffffff00000000 if 64BIT 286 default 0xffffffff if 32BIT 287 288config ARCH_FLATMEM_ENABLE 289 def_bool !NUMA 290 291config ARCH_SPARSEMEM_ENABLE 292 def_bool y 293 depends on MMU 294 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 295 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 296 297config ARCH_SELECT_MEMORY_MODEL 298 def_bool ARCH_SPARSEMEM_ENABLE 299 300config ARCH_SUPPORTS_UPROBES 301 def_bool y 302 303config STACKTRACE_SUPPORT 304 def_bool y 305 306config GENERIC_BUG 307 def_bool y 308 depends on BUG 309 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 310 311config GENERIC_BUG_RELATIVE_POINTERS 312 bool 313 314config GENERIC_CALIBRATE_DELAY 315 def_bool y 316 317config GENERIC_CSUM 318 def_bool y 319 320config GENERIC_HWEIGHT 321 def_bool y 322 323config FIX_EARLYCON_MEM 324 def_bool MMU 325 326config PGTABLE_LEVELS 327 int 328 default 5 if 64BIT 329 default 2 330 331config LOCKDEP_SUPPORT 332 def_bool y 333 334config RISCV_DMA_NONCOHERENT 335 bool 336 select ARCH_HAS_DMA_PREP_COHERENT 337 select ARCH_HAS_SETUP_DMA_OPS 338 select ARCH_HAS_SYNC_DMA_FOR_CPU 339 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 340 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 341 342config RISCV_NONSTANDARD_CACHE_OPS 343 bool 344 help 345 This enables function pointer support for non-standard noncoherent 346 systems to handle cache management. 347 348config AS_HAS_INSN 349 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 350 351config AS_HAS_OPTION_ARCH 352 # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4 353 def_bool y 354 depends on $(as-instr, .option arch$(comma) +m) 355 356source "arch/riscv/Kconfig.socs" 357source "arch/riscv/Kconfig.errata" 358 359menu "Platform type" 360 361config NONPORTABLE 362 bool "Allow configurations that result in non-portable kernels" 363 help 364 RISC-V kernel binaries are compatible between all known systems 365 whenever possible, but there are some use cases that can only be 366 satisfied by configurations that result in kernel binaries that are 367 not portable between systems. 368 369 Selecting N does not guarantee kernels will be portable to all known 370 systems. Selecting any of the options guarded by NONPORTABLE will 371 result in kernel binaries that are unlikely to be portable between 372 systems. 373 374 If unsure, say N. 375 376choice 377 prompt "Base ISA" 378 default ARCH_RV64I 379 help 380 This selects the base ISA that this kernel will target and must match 381 the target platform. 382 383config ARCH_RV32I 384 bool "RV32I" 385 depends on NONPORTABLE 386 select 32BIT 387 select GENERIC_LIB_ASHLDI3 388 select GENERIC_LIB_ASHRDI3 389 select GENERIC_LIB_LSHRDI3 390 select GENERIC_LIB_UCMPDI2 391 392config ARCH_RV64I 393 bool "RV64I" 394 select 64BIT 395 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 396 select SWIOTLB if MMU 397 398endchoice 399 400# We must be able to map all physical memory into the kernel, but the compiler 401# is still a bit more efficient when generating code if it's setup in a manner 402# such that it can only map 2GiB of memory. 403choice 404 prompt "Kernel Code Model" 405 default CMODEL_MEDLOW if 32BIT 406 default CMODEL_MEDANY if 64BIT 407 408 config CMODEL_MEDLOW 409 bool "medium low code model" 410 config CMODEL_MEDANY 411 bool "medium any code model" 412endchoice 413 414config MODULE_SECTIONS 415 bool 416 select HAVE_MOD_ARCH_SPECIFIC 417 418config SMP 419 bool "Symmetric Multi-Processing" 420 help 421 This enables support for systems with more than one CPU. If 422 you say N here, the kernel will run on single and 423 multiprocessor machines, but will use only one CPU of a 424 multiprocessor machine. If you say Y here, the kernel will run 425 on many, but not all, single processor machines. On a single 426 processor machine, the kernel will run faster if you say N 427 here. 428 429 If you don't know what to do here, say N. 430 431config SCHED_MC 432 bool "Multi-core scheduler support" 433 depends on SMP 434 help 435 Multi-core scheduler support improves the CPU scheduler's decision 436 making when dealing with multi-core CPU chips at a cost of slightly 437 increased overhead in some places. If unsure say N here. 438 439config NR_CPUS 440 int "Maximum number of CPUs (2-512)" 441 depends on SMP 442 range 2 512 if !RISCV_SBI_V01 443 range 2 32 if RISCV_SBI_V01 && 32BIT 444 range 2 64 if RISCV_SBI_V01 && 64BIT 445 default "32" if 32BIT 446 default "64" if 64BIT 447 448config HOTPLUG_CPU 449 bool "Support for hot-pluggable CPUs" 450 depends on SMP 451 select GENERIC_IRQ_MIGRATION 452 help 453 454 Say Y here to experiment with turning CPUs off and on. CPUs 455 can be controlled through /sys/devices/system/cpu. 456 457 Say N if you want to disable CPU hotplug. 458 459choice 460 prompt "CPU Tuning" 461 default TUNE_GENERIC 462 463config TUNE_GENERIC 464 bool "generic" 465 466endchoice 467 468# Common NUMA Features 469config NUMA 470 bool "NUMA Memory Allocation and Scheduler Support" 471 depends on SMP && MMU 472 select ARCH_SUPPORTS_NUMA_BALANCING 473 select GENERIC_ARCH_NUMA 474 select HAVE_SETUP_PER_CPU_AREA 475 select NEED_PER_CPU_EMBED_FIRST_CHUNK 476 select NEED_PER_CPU_PAGE_FIRST_CHUNK 477 select OF_NUMA 478 select USE_PERCPU_NUMA_NODE_ID 479 help 480 Enable NUMA (Non-Uniform Memory Access) support. 481 482 The kernel will try to allocate memory used by a CPU on the 483 local memory of the CPU and add some more NUMA awareness to the kernel. 484 485config NODES_SHIFT 486 int "Maximum NUMA Nodes (as a power of 2)" 487 range 1 10 488 default "2" 489 depends on NUMA 490 help 491 Specify the maximum number of NUMA Nodes available on the target 492 system. Increases memory reserved to accommodate various tables. 493 494config RISCV_ALTERNATIVE 495 bool 496 depends on !XIP_KERNEL 497 help 498 This Kconfig allows the kernel to automatically patch the 499 erratum or cpufeature required by the execution platform at run 500 time. The code patching overhead is minimal, as it's only done 501 once at boot and once on each module load. 502 503config RISCV_ALTERNATIVE_EARLY 504 bool 505 depends on RISCV_ALTERNATIVE 506 help 507 Allows early patching of the kernel for special errata 508 509config RISCV_ISA_C 510 bool "Emit compressed instructions when building Linux" 511 default y 512 help 513 Adds "C" to the ISA subsets that the toolchain is allowed to emit 514 when building Linux, which results in compressed instructions in the 515 Linux binary. 516 517 If you don't know what to do here, say Y. 518 519config RISCV_ISA_SVNAPOT 520 bool "Svnapot extension support for supervisor mode NAPOT pages" 521 depends on 64BIT && MMU 522 depends on RISCV_ALTERNATIVE 523 default y 524 help 525 Allow kernel to detect the Svnapot ISA-extension dynamically at boot 526 time and enable its usage. 527 528 The Svnapot extension is used to mark contiguous PTEs as a range 529 of contiguous virtual-to-physical translations for a naturally 530 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 531 size. When HUGETLBFS is also selected this option unconditionally 532 allocates some memory for each NAPOT page size supported by the kernel. 533 When optimizing for low memory consumption and for platforms without 534 the Svnapot extension, it may be better to say N here. 535 536 If you don't know what to do here, say Y. 537 538config RISCV_ISA_SVPBMT 539 bool "Svpbmt extension support for supervisor mode page-based memory types" 540 depends on 64BIT && MMU 541 depends on RISCV_ALTERNATIVE 542 default y 543 help 544 Adds support to dynamically detect the presence of the Svpbmt 545 ISA-extension (Supervisor-mode: page-based memory types) and 546 enable its usage. 547 548 The memory type for a page contains a combination of attributes 549 that indicate the cacheability, idempotency, and ordering 550 properties for access to that page. 551 552 The Svpbmt extension is only available on 64-bit cpus. 553 554 If you don't know what to do here, say Y. 555 556config TOOLCHAIN_HAS_V 557 bool 558 default y 559 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64imv) 560 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32imv) 561 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 562 depends on AS_HAS_OPTION_ARCH 563 564config RISCV_ISA_V 565 bool "VECTOR extension support" 566 depends on TOOLCHAIN_HAS_V 567 depends on FPU 568 select DYNAMIC_SIGFRAME 569 default y 570 help 571 Say N here if you want to disable all vector related procedure 572 in the kernel. 573 574 If you don't know what to do here, say Y. 575 576config RISCV_ISA_V_DEFAULT_ENABLE 577 bool "Enable userspace Vector by default" 578 depends on RISCV_ISA_V 579 default y 580 help 581 Say Y here if you want to enable Vector in userspace by default. 582 Otherwise, userspace has to make explicit prctl() call to enable 583 Vector, or enable it via the sysctl interface. 584 585 If you don't know what to do here, say Y. 586 587config RISCV_ISA_V_UCOPY_THRESHOLD 588 int "Threshold size for vectorized user copies" 589 depends on RISCV_ISA_V 590 default 768 591 help 592 Prefer using vectorized copy_to_user()/copy_from_user() when the 593 workload size exceeds this value. 594 595config RISCV_ISA_V_PREEMPTIVE 596 bool "Run kernel-mode Vector with kernel preemption" 597 depends on PREEMPTION 598 depends on RISCV_ISA_V 599 default y 600 help 601 Usually, in-kernel SIMD routines are run with preemption disabled. 602 Functions which envoke long running SIMD thus must yield core's 603 vector unit to prevent blocking other tasks for too long. 604 605 This config allows kernel to run SIMD without explicitly disable 606 preemption. Enabling this config will result in higher memory 607 consumption due to the allocation of per-task's kernel Vector context. 608 609config RISCV_ISA_ZAWRS 610 bool "Zawrs extension support for more efficient busy waiting" 611 depends on RISCV_ALTERNATIVE 612 default y 613 help 614 The Zawrs extension defines instructions to be used in polling loops 615 which allow a hart to enter a low-power state or to trap to the 616 hypervisor while waiting on a store to a memory location. Enable the 617 use of these instructions in the kernel when the Zawrs extension is 618 detected at boot. 619 620 If you don't know what to do here, say Y. 621 622config TOOLCHAIN_HAS_ZBB 623 bool 624 default y 625 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 626 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 627 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 628 depends on AS_HAS_OPTION_ARCH 629 630# This symbol indicates that the toolchain supports all v1.0 vector crypto 631# extensions, including Zvk*, Zvbb, and Zvbc. LLVM added all of these at once. 632# binutils added all except Zvkb, then added Zvkb. So we just check for Zvkb. 633config TOOLCHAIN_HAS_VECTOR_CRYPTO 634 def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb) 635 depends on AS_HAS_OPTION_ARCH 636 637config RISCV_ISA_ZBA 638 bool "Zba extension support for bit manipulation instructions" 639 default y 640 help 641 Add support for enabling optimisations in the kernel when the Zba 642 extension is detected at boot. 643 644 The Zba extension provides instructions to accelerate the generation 645 of addresses that index into arrays of basic data types. 646 647 If you don't know what to do here, say Y. 648 649config RISCV_ISA_ZBB 650 bool "Zbb extension support for bit manipulation instructions" 651 depends on TOOLCHAIN_HAS_ZBB 652 depends on RISCV_ALTERNATIVE 653 default y 654 help 655 Adds support to dynamically detect the presence of the ZBB 656 extension (basic bit manipulation) and enable its usage. 657 658 The Zbb extension provides instructions to accelerate a number 659 of bit-specific operations (count bit population, sign extending, 660 bitrotation, etc). 661 662 If you don't know what to do here, say Y. 663 664config TOOLCHAIN_HAS_ZBC 665 bool 666 default y 667 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc) 668 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc) 669 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 670 depends on AS_HAS_OPTION_ARCH 671 672config RISCV_ISA_ZBC 673 bool "Zbc extension support for carry-less multiplication instructions" 674 depends on TOOLCHAIN_HAS_ZBC 675 depends on MMU 676 depends on RISCV_ALTERNATIVE 677 default y 678 help 679 Adds support to dynamically detect the presence of the Zbc 680 extension (carry-less multiplication) and enable its usage. 681 682 The Zbc extension could accelerate CRC (cyclic redundancy check) 683 calculations. 684 685 If you don't know what to do here, say Y. 686 687config RISCV_ISA_ZICBOM 688 bool "Zicbom extension support for non-coherent DMA operation" 689 depends on MMU 690 depends on RISCV_ALTERNATIVE 691 default y 692 select RISCV_DMA_NONCOHERENT 693 select DMA_DIRECT_REMAP 694 help 695 Adds support to dynamically detect the presence of the ZICBOM 696 extension (Cache Block Management Operations) and enable its 697 usage. 698 699 The Zicbom extension can be used to handle for example 700 non-coherent DMA support on devices that need it. 701 702 If you don't know what to do here, say Y. 703 704config RISCV_ISA_ZICBOZ 705 bool "Zicboz extension support for faster zeroing of memory" 706 depends on RISCV_ALTERNATIVE 707 default y 708 help 709 Enable the use of the Zicboz extension (cbo.zero instruction) 710 when available. 711 712 The Zicboz extension is used for faster zeroing of memory. 713 714 If you don't know what to do here, say Y. 715 716config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 717 def_bool y 718 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 719 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 720 depends on AS_IS_GNU && AS_VERSION >= 23600 721 help 722 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 723 20191213 version, which moves some instructions from the I extension to 724 the Zicsr and Zifencei extensions. This requires explicitly specifying 725 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 726 and Zifencei are supported in binutils from version 2.36 onwards. 727 To make life easier, and avoid forcing toolchains that default to a 728 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 729 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 730 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 731 732config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 733 def_bool y 734 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 735 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 736 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 737 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 738 help 739 Certain versions of clang and GCC do not support zicsr and zifencei via 740 -march. This option causes an older ISA spec compatible with these older 741 versions of clang and GCC to be passed to GAS, which has the same result 742 as passing zicsr and zifencei to -march. 743 744config FPU 745 bool "FPU support" 746 default y 747 help 748 Say N here if you want to disable all floating-point related procedure 749 in the kernel. 750 751 If you don't know what to do here, say Y. 752 753config IRQ_STACKS 754 bool "Independent irq & softirq stacks" if EXPERT 755 default y 756 select HAVE_IRQ_EXIT_ON_IRQ_STACK 757 select HAVE_SOFTIRQ_ON_OWN_STACK 758 help 759 Add independent irq & softirq stacks for percpu to prevent kernel stack 760 overflows. We may save some memory footprint by disabling IRQ_STACKS. 761 762config THREAD_SIZE_ORDER 763 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 764 range 0 4 765 default 1 if 32BIT && !KASAN 766 default 3 if 64BIT && KASAN 767 default 2 768 help 769 Specify the Pages of thread stack size (from 4KB to 64KB), which also 770 affects irq stack size, which is equal to thread stack size. 771 772config RISCV_MISALIGNED 773 bool 774 select SYSCTL_ARCH_UNALIGN_ALLOW 775 help 776 Embed support for emulating misaligned loads and stores. 777 778choice 779 prompt "Unaligned Accesses Support" 780 default RISCV_PROBE_UNALIGNED_ACCESS 781 help 782 This determines the level of support for unaligned accesses. This 783 information is used by the kernel to perform optimizations. It is also 784 exposed to user space via the hwprobe syscall. The hardware will be 785 probed at boot by default. 786 787config RISCV_PROBE_UNALIGNED_ACCESS 788 bool "Probe for hardware unaligned access support" 789 select RISCV_MISALIGNED 790 help 791 During boot, the kernel will run a series of tests to determine the 792 speed of unaligned accesses. This probing will dynamically determine 793 the speed of unaligned accesses on the underlying system. If unaligned 794 memory accesses trap into the kernel as they are not supported by the 795 system, the kernel will emulate the unaligned accesses to preserve the 796 UABI. 797 798config RISCV_EMULATED_UNALIGNED_ACCESS 799 bool "Emulate unaligned access where system support is missing" 800 select RISCV_MISALIGNED 801 help 802 If unaligned memory accesses trap into the kernel as they are not 803 supported by the system, the kernel will emulate the unaligned 804 accesses to preserve the UABI. When the underlying system does support 805 unaligned accesses, the unaligned accesses are assumed to be slow. 806 807config RISCV_SLOW_UNALIGNED_ACCESS 808 bool "Assume the system supports slow unaligned memory accesses" 809 depends on NONPORTABLE 810 help 811 Assume that the system supports slow unaligned memory accesses. The 812 kernel and userspace programs may not be able to run at all on systems 813 that do not support unaligned memory accesses. 814 815config RISCV_EFFICIENT_UNALIGNED_ACCESS 816 bool "Assume the system supports fast unaligned memory accesses" 817 depends on NONPORTABLE 818 select DCACHE_WORD_ACCESS if MMU 819 select HAVE_EFFICIENT_UNALIGNED_ACCESS 820 help 821 Assume that the system supports fast unaligned memory accesses. When 822 enabled, this option improves the performance of the kernel on such 823 systems. However, the kernel and userspace programs will run much more 824 slowly, or will not be able to run at all, on systems that do not 825 support efficient unaligned memory accesses. 826 827endchoice 828 829source "arch/riscv/Kconfig.vendor" 830 831endmenu # "Platform type" 832 833menu "Kernel features" 834 835source "kernel/Kconfig.hz" 836 837config RISCV_SBI_V01 838 bool "SBI v0.1 support" 839 depends on RISCV_SBI 840 help 841 This config allows kernel to use SBI v0.1 APIs. This will be 842 deprecated in future once legacy M-mode software are no longer in use. 843 844config RISCV_BOOT_SPINWAIT 845 bool "Spinwait booting method" 846 depends on SMP 847 default y if RISCV_SBI_V01 || RISCV_M_MODE 848 help 849 This enables support for booting Linux via spinwait method. In the 850 spinwait method, all cores randomly jump to Linux. One of the cores 851 gets chosen via lottery and all other keep spinning on a percpu 852 variable. This method cannot support CPU hotplug and sparse hartid 853 scheme. It should be only enabled for M-mode Linux or platforms relying 854 on older firmware without SBI HSM extension. All other platforms should 855 rely on ordered booting via SBI HSM extension which gets chosen 856 dynamically at runtime if the firmware supports it. 857 858 Since spinwait is incompatible with sparse hart IDs, it requires 859 NR_CPUS be large enough to contain the physical hart ID of the first 860 hart to enter Linux. 861 862 If unsure what to do here, say N. 863 864config ARCH_SUPPORTS_KEXEC 865 def_bool y 866 867config ARCH_SELECTS_KEXEC 868 def_bool y 869 depends on KEXEC 870 select HOTPLUG_CPU if SMP 871 872config ARCH_SUPPORTS_KEXEC_FILE 873 def_bool 64BIT 874 875config ARCH_SELECTS_KEXEC_FILE 876 def_bool y 877 depends on KEXEC_FILE 878 select HAVE_IMA_KEXEC if IMA 879 select KEXEC_ELF 880 881config ARCH_SUPPORTS_KEXEC_PURGATORY 882 def_bool ARCH_SUPPORTS_KEXEC_FILE 883 884config ARCH_SUPPORTS_CRASH_DUMP 885 def_bool y 886 887config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 888 def_bool CRASH_RESERVE 889 890config COMPAT 891 bool "Kernel support for 32-bit U-mode" 892 default 64BIT 893 depends on 64BIT && MMU 894 help 895 This option enables support for a 32-bit U-mode running under a 64-bit 896 kernel at S-mode. riscv32-specific components such as system calls, 897 the user helper functions (vdso), signal rt_frame functions and the 898 ptrace interface are handled appropriately by the kernel. 899 900 If you want to execute 32-bit userspace applications, say Y. 901 902config PARAVIRT 903 bool "Enable paravirtualization code" 904 depends on RISCV_SBI 905 help 906 This changes the kernel so it can modify itself when it is run 907 under a hypervisor, potentially improving performance significantly 908 over full virtualization. 909 910config PARAVIRT_TIME_ACCOUNTING 911 bool "Paravirtual steal time accounting" 912 depends on PARAVIRT 913 help 914 Select this option to enable fine granularity task steal time 915 accounting. Time spent executing other tasks in parallel with 916 the current vCPU is discounted from the vCPU power. To account for 917 that, there can be a small performance impact. 918 919 If in doubt, say N here. 920 921config RELOCATABLE 922 bool "Build a relocatable kernel" 923 depends on MMU && 64BIT && !XIP_KERNEL 924 select MODULE_SECTIONS if MODULES 925 help 926 This builds a kernel as a Position Independent Executable (PIE), 927 which retains all relocation metadata required to relocate the 928 kernel binary at runtime to a different virtual address than the 929 address it was linked at. 930 Since RISCV uses the RELA relocation format, this requires a 931 relocation pass at runtime even if the kernel is loaded at the 932 same address it was linked at. 933 934 If unsure, say N. 935 936config RANDOMIZE_BASE 937 bool "Randomize the address of the kernel image" 938 select RELOCATABLE 939 depends on MMU && 64BIT && !XIP_KERNEL 940 help 941 Randomizes the virtual address at which the kernel image is 942 loaded, as a security feature that deters exploit attempts 943 relying on knowledge of the location of kernel internals. 944 945 It is the bootloader's job to provide entropy, by passing a 946 random u64 value in /chosen/kaslr-seed at kernel entry. 947 948 When booting via the UEFI stub, it will invoke the firmware's 949 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 950 to the kernel proper. In addition, it will randomise the physical 951 location of the kernel Image as well. 952 953 If unsure, say N. 954 955endmenu # "Kernel features" 956 957menu "Boot options" 958 959config CMDLINE 960 string "Built-in kernel command line" 961 help 962 For most platforms, the arguments for the kernel's command line 963 are provided at run-time, during boot. However, there are cases 964 where either no arguments are being provided or the provided 965 arguments are insufficient or even invalid. 966 967 When that occurs, it is possible to define a built-in command 968 line here and choose how the kernel should use it later on. 969 970choice 971 prompt "Built-in command line usage" 972 depends on CMDLINE != "" 973 default CMDLINE_FALLBACK 974 help 975 Choose how the kernel will handle the provided built-in command 976 line. 977 978config CMDLINE_FALLBACK 979 bool "Use bootloader kernel arguments if available" 980 help 981 Use the built-in command line as fallback in case we get nothing 982 during boot. This is the default behaviour. 983 984config CMDLINE_EXTEND 985 bool "Extend bootloader kernel arguments" 986 help 987 The command-line arguments provided during boot will be 988 appended to the built-in command line. This is useful in 989 cases where the provided arguments are insufficient and 990 you don't want to or cannot modify them. 991 992config CMDLINE_FORCE 993 bool "Always use the default kernel command string" 994 help 995 Always use the built-in command line, even if we get one during 996 boot. This is useful in case you need to override the provided 997 command line on systems where you don't have or want control 998 over it. 999 1000endchoice 1001 1002config EFI_STUB 1003 bool 1004 1005config EFI 1006 bool "UEFI runtime support" 1007 depends on OF && !XIP_KERNEL 1008 depends on MMU 1009 default y 1010 select ARCH_SUPPORTS_ACPI if 64BIT 1011 select EFI_GENERIC_STUB 1012 select EFI_PARAMS_FROM_FDT 1013 select EFI_RUNTIME_WRAPPERS 1014 select EFI_STUB 1015 select LIBFDT 1016 select RISCV_ISA_C 1017 select UCS2_STRING 1018 help 1019 This option provides support for runtime services provided 1020 by UEFI firmware (such as non-volatile variables, realtime 1021 clock, and platform reset). A UEFI stub is also provided to 1022 allow the kernel to be booted as an EFI application. This 1023 is only useful on systems that have UEFI firmware. 1024 1025config DMI 1026 bool "Enable support for SMBIOS (DMI) tables" 1027 depends on EFI 1028 default y 1029 help 1030 This enables SMBIOS/DMI feature for systems. 1031 1032 This option is only useful on systems that have UEFI firmware. 1033 However, even with this option, the resultant kernel should 1034 continue to boot on existing non-UEFI platforms. 1035 1036config CC_HAVE_STACKPROTECTOR_TLS 1037 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 1038 1039config STACKPROTECTOR_PER_TASK 1040 def_bool y 1041 depends on !RANDSTRUCT 1042 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 1043 1044config PHYS_RAM_BASE_FIXED 1045 bool "Explicitly specified physical RAM address" 1046 depends on NONPORTABLE 1047 default n 1048 1049config PHYS_RAM_BASE 1050 hex "Platform Physical RAM address" 1051 depends on PHYS_RAM_BASE_FIXED 1052 default "0x80000000" 1053 help 1054 This is the physical address of RAM in the system. It has to be 1055 explicitly specified to run early relocations of read-write data 1056 from flash to RAM. 1057 1058config XIP_KERNEL 1059 bool "Kernel Execute-In-Place from ROM" 1060 depends on MMU && SPARSEMEM && NONPORTABLE 1061 # This prevents XIP from being enabled by all{yes,mod}config, which 1062 # fail to build since XIP doesn't support large kernels. 1063 depends on !COMPILE_TEST 1064 select PHYS_RAM_BASE_FIXED 1065 help 1066 Execute-In-Place allows the kernel to run from non-volatile storage 1067 directly addressable by the CPU, such as NOR flash. This saves RAM 1068 space since the text section of the kernel is not loaded from flash 1069 to RAM. Read-write sections, such as the data section and stack, 1070 are still copied to RAM. The XIP kernel is not compressed since 1071 it has to run directly from flash, so it will take more space to 1072 store it. The flash address used to link the kernel object files, 1073 and for storing it, is configuration dependent. Therefore, if you 1074 say Y here, you must know the proper physical address where to 1075 store the kernel image depending on your own flash memory usage. 1076 1077 Also note that the make target becomes "make xipImage" rather than 1078 "make zImage" or "make Image". The final kernel binary to put in 1079 ROM memory will be arch/riscv/boot/xipImage. 1080 1081 SPARSEMEM is required because the kernel text and rodata that are 1082 flash resident are not backed by memmap, then any attempt to get 1083 a struct page on those regions will trigger a fault. 1084 1085 If unsure, say N. 1086 1087config XIP_PHYS_ADDR 1088 hex "XIP Kernel Physical Location" 1089 depends on XIP_KERNEL 1090 default "0x21000000" 1091 help 1092 This is the physical address in your flash memory the kernel will 1093 be linked for and stored to. This address is dependent on your 1094 own flash usage. 1095 1096config RISCV_ISA_FALLBACK 1097 bool "Permit falling back to parsing riscv,isa for extension support by default" 1098 default y 1099 help 1100 Parsing the "riscv,isa" devicetree property has been deprecated and 1101 replaced by a list of explicitly defined strings. For compatibility 1102 with existing platforms, the kernel will fall back to parsing the 1103 "riscv,isa" property if the replacements are not found. 1104 1105 Selecting N here will result in a kernel that does not use the 1106 fallback, unless the commandline "riscv_isa_fallback" parameter is 1107 present. 1108 1109 Please see the dt-binding, located at 1110 Documentation/devicetree/bindings/riscv/extensions.yaml for details 1111 on the replacement properties, "riscv,isa-base" and 1112 "riscv,isa-extensions". 1113 1114config BUILTIN_DTB 1115 bool "Built-in device tree" 1116 depends on OF && NONPORTABLE 1117 help 1118 Build a device tree into the Linux image. 1119 This option should be selected if no bootloader is being used. 1120 If unsure, say N. 1121 1122 1123config BUILTIN_DTB_SOURCE 1124 string "Built-in device tree source" 1125 depends on BUILTIN_DTB 1126 help 1127 DTS file path (without suffix, relative to arch/riscv/boot/dts) 1128 for the DTS file that will be used to produce the DTB linked into the 1129 kernel. 1130 1131endmenu # "Boot options" 1132 1133config PORTABLE 1134 bool 1135 default !NONPORTABLE 1136 select EFI 1137 select MMU 1138 select OF 1139 1140config ARCH_PROC_KCORE_TEXT 1141 def_bool y 1142 1143menu "Power management options" 1144 1145source "kernel/power/Kconfig" 1146 1147config ARCH_HIBERNATION_POSSIBLE 1148 def_bool y 1149 1150config ARCH_HIBERNATION_HEADER 1151 def_bool HIBERNATION 1152 1153config ARCH_SUSPEND_POSSIBLE 1154 def_bool y 1155 1156endmenu # "Power management options" 1157 1158menu "CPU Power Management" 1159 1160source "drivers/cpuidle/Kconfig" 1161 1162source "drivers/cpufreq/Kconfig" 1163 1164endmenu # "CPU Power Management" 1165 1166source "arch/riscv/kvm/Kconfig" 1167 1168source "drivers/acpi/Kconfig" 1169