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 PGTABLE_LEVELS 324 int 325 default 5 if 64BIT 326 default 2 327 328config LOCKDEP_SUPPORT 329 def_bool y 330 331config RISCV_DMA_NONCOHERENT 332 bool 333 select ARCH_HAS_DMA_PREP_COHERENT 334 select ARCH_HAS_SETUP_DMA_OPS 335 select ARCH_HAS_SYNC_DMA_FOR_CPU 336 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 337 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 338 339config RISCV_NONSTANDARD_CACHE_OPS 340 bool 341 help 342 This enables function pointer support for non-standard noncoherent 343 systems to handle cache management. 344 345config AS_HAS_INSN 346 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 347 348config AS_HAS_OPTION_ARCH 349 # https://github.com/llvm/llvm-project/commit/9e8ed3403c191ab9c4903e8eeb8f732ff8a43cb4 350 def_bool y 351 depends on $(as-instr, .option arch$(comma) +m) 352 353source "arch/riscv/Kconfig.socs" 354source "arch/riscv/Kconfig.errata" 355 356menu "Platform type" 357 358config NONPORTABLE 359 bool "Allow configurations that result in non-portable kernels" 360 help 361 RISC-V kernel binaries are compatible between all known systems 362 whenever possible, but there are some use cases that can only be 363 satisfied by configurations that result in kernel binaries that are 364 not portable between systems. 365 366 Selecting N does not guarantee kernels will be portable to all known 367 systems. Selecting any of the options guarded by NONPORTABLE will 368 result in kernel binaries that are unlikely to be portable between 369 systems. 370 371 If unsure, say N. 372 373choice 374 prompt "Base ISA" 375 default ARCH_RV64I 376 help 377 This selects the base ISA that this kernel will target and must match 378 the target platform. 379 380config ARCH_RV32I 381 bool "RV32I" 382 depends on NONPORTABLE 383 select 32BIT 384 select GENERIC_LIB_ASHLDI3 385 select GENERIC_LIB_ASHRDI3 386 select GENERIC_LIB_LSHRDI3 387 select GENERIC_LIB_UCMPDI2 388 389config ARCH_RV64I 390 bool "RV64I" 391 select 64BIT 392 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 393 select SWIOTLB if MMU 394 395endchoice 396 397# We must be able to map all physical memory into the kernel, but the compiler 398# is still a bit more efficient when generating code if it's setup in a manner 399# such that it can only map 2GiB of memory. 400choice 401 prompt "Kernel Code Model" 402 default CMODEL_MEDLOW if 32BIT 403 default CMODEL_MEDANY if 64BIT 404 405 config CMODEL_MEDLOW 406 bool "medium low code model" 407 config CMODEL_MEDANY 408 bool "medium any code model" 409endchoice 410 411config MODULE_SECTIONS 412 bool 413 select HAVE_MOD_ARCH_SPECIFIC 414 415config SMP 416 bool "Symmetric Multi-Processing" 417 help 418 This enables support for systems with more than one CPU. If 419 you say N here, the kernel will run on single and 420 multiprocessor machines, but will use only one CPU of a 421 multiprocessor machine. If you say Y here, the kernel will run 422 on many, but not all, single processor machines. On a single 423 processor machine, the kernel will run faster if you say N 424 here. 425 426 If you don't know what to do here, say N. 427 428config SCHED_MC 429 bool "Multi-core scheduler support" 430 depends on SMP 431 help 432 Multi-core scheduler support improves the CPU scheduler's decision 433 making when dealing with multi-core CPU chips at a cost of slightly 434 increased overhead in some places. If unsure say N here. 435 436config NR_CPUS 437 int "Maximum number of CPUs (2-512)" 438 depends on SMP 439 range 2 512 if !RISCV_SBI_V01 440 range 2 32 if RISCV_SBI_V01 && 32BIT 441 range 2 64 if RISCV_SBI_V01 && 64BIT 442 default "32" if 32BIT 443 default "64" if 64BIT 444 445config HOTPLUG_CPU 446 bool "Support for hot-pluggable CPUs" 447 depends on SMP 448 select GENERIC_IRQ_MIGRATION 449 help 450 451 Say Y here to experiment with turning CPUs off and on. CPUs 452 can be controlled through /sys/devices/system/cpu. 453 454 Say N if you want to disable CPU hotplug. 455 456choice 457 prompt "CPU Tuning" 458 default TUNE_GENERIC 459 460config TUNE_GENERIC 461 bool "generic" 462 463endchoice 464 465# Common NUMA Features 466config NUMA 467 bool "NUMA Memory Allocation and Scheduler Support" 468 depends on SMP && MMU 469 select ARCH_SUPPORTS_NUMA_BALANCING 470 select GENERIC_ARCH_NUMA 471 select HAVE_SETUP_PER_CPU_AREA 472 select NEED_PER_CPU_EMBED_FIRST_CHUNK 473 select NEED_PER_CPU_PAGE_FIRST_CHUNK 474 select OF_NUMA 475 select USE_PERCPU_NUMA_NODE_ID 476 help 477 Enable NUMA (Non-Uniform Memory Access) support. 478 479 The kernel will try to allocate memory used by a CPU on the 480 local memory of the CPU and add some more NUMA awareness to the kernel. 481 482config NODES_SHIFT 483 int "Maximum NUMA Nodes (as a power of 2)" 484 range 1 10 485 default "2" 486 depends on NUMA 487 help 488 Specify the maximum number of NUMA Nodes available on the target 489 system. Increases memory reserved to accommodate various tables. 490 491config RISCV_ALTERNATIVE 492 bool 493 depends on !XIP_KERNEL 494 help 495 This Kconfig allows the kernel to automatically patch the 496 erratum or cpufeature required by the execution platform at run 497 time. The code patching overhead is minimal, as it's only done 498 once at boot and once on each module load. 499 500config RISCV_ALTERNATIVE_EARLY 501 bool 502 depends on RISCV_ALTERNATIVE 503 help 504 Allows early patching of the kernel for special errata 505 506config RISCV_ISA_C 507 bool "Emit compressed instructions when building Linux" 508 default y 509 help 510 Adds "C" to the ISA subsets that the toolchain is allowed to emit 511 when building Linux, which results in compressed instructions in the 512 Linux binary. 513 514 If you don't know what to do here, say Y. 515 516config RISCV_ISA_SVNAPOT 517 bool "Svnapot extension support for supervisor mode NAPOT pages" 518 depends on 64BIT && MMU 519 depends on RISCV_ALTERNATIVE 520 default y 521 help 522 Allow kernel to detect the Svnapot ISA-extension dynamically at boot 523 time and enable its usage. 524 525 The Svnapot extension is used to mark contiguous PTEs as a range 526 of contiguous virtual-to-physical translations for a naturally 527 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 528 size. When HUGETLBFS is also selected this option unconditionally 529 allocates some memory for each NAPOT page size supported by the kernel. 530 When optimizing for low memory consumption and for platforms without 531 the Svnapot extension, it may be better to say N here. 532 533 If you don't know what to do here, say Y. 534 535config RISCV_ISA_SVPBMT 536 bool "Svpbmt extension support for supervisor mode page-based memory types" 537 depends on 64BIT && MMU 538 depends on RISCV_ALTERNATIVE 539 default y 540 help 541 Adds support to dynamically detect the presence of the Svpbmt 542 ISA-extension (Supervisor-mode: page-based memory types) and 543 enable its usage. 544 545 The memory type for a page contains a combination of attributes 546 that indicate the cacheability, idempotency, and ordering 547 properties for access to that page. 548 549 The Svpbmt extension is only available on 64-bit cpus. 550 551 If you don't know what to do here, say Y. 552 553config TOOLCHAIN_HAS_V 554 bool 555 default y 556 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64iv) 557 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32iv) 558 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 559 depends on AS_HAS_OPTION_ARCH 560 561config RISCV_ISA_V 562 bool "VECTOR extension support" 563 depends on TOOLCHAIN_HAS_V 564 depends on FPU 565 select DYNAMIC_SIGFRAME 566 default y 567 help 568 Say N here if you want to disable all vector related procedure 569 in the kernel. 570 571 If you don't know what to do here, say Y. 572 573config RISCV_ISA_V_DEFAULT_ENABLE 574 bool "Enable userspace Vector by default" 575 depends on RISCV_ISA_V 576 default y 577 help 578 Say Y here if you want to enable Vector in userspace by default. 579 Otherwise, userspace has to make explicit prctl() call to enable 580 Vector, or enable it via the sysctl interface. 581 582 If you don't know what to do here, say Y. 583 584config RISCV_ISA_V_UCOPY_THRESHOLD 585 int "Threshold size for vectorized user copies" 586 depends on RISCV_ISA_V 587 default 768 588 help 589 Prefer using vectorized copy_to_user()/copy_from_user() when the 590 workload size exceeds this value. 591 592config RISCV_ISA_V_PREEMPTIVE 593 bool "Run kernel-mode Vector with kernel preemption" 594 depends on PREEMPTION 595 depends on RISCV_ISA_V 596 default y 597 help 598 Usually, in-kernel SIMD routines are run with preemption disabled. 599 Functions which envoke long running SIMD thus must yield core's 600 vector unit to prevent blocking other tasks for too long. 601 602 This config allows kernel to run SIMD without explicitly disable 603 preemption. Enabling this config will result in higher memory 604 consumption due to the allocation of per-task's kernel Vector context. 605 606config RISCV_ISA_ZAWRS 607 bool "Zawrs extension support for more efficient busy waiting" 608 depends on RISCV_ALTERNATIVE 609 default y 610 help 611 The Zawrs extension defines instructions to be used in polling loops 612 which allow a hart to enter a low-power state or to trap to the 613 hypervisor while waiting on a store to a memory location. Enable the 614 use of these instructions in the kernel when the Zawrs extension is 615 detected at boot. 616 617 If you don't know what to do here, say Y. 618 619config TOOLCHAIN_HAS_ZBB 620 bool 621 default y 622 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 623 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 624 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 625 depends on AS_HAS_OPTION_ARCH 626 627# This symbol indicates that the toolchain supports all v1.0 vector crypto 628# extensions, including Zvk*, Zvbb, and Zvbc. LLVM added all of these at once. 629# binutils added all except Zvkb, then added Zvkb. So we just check for Zvkb. 630config TOOLCHAIN_HAS_VECTOR_CRYPTO 631 def_bool $(as-instr, .option arch$(comma) +v$(comma) +zvkb) 632 depends on AS_HAS_OPTION_ARCH 633 634config RISCV_ISA_ZBA 635 bool "Zba extension support for bit manipulation instructions" 636 default y 637 help 638 Add support for enabling optimisations in the kernel when the Zba 639 extension is detected at boot. 640 641 The Zba extension provides instructions to accelerate the generation 642 of addresses that index into arrays of basic data types. 643 644 If you don't know what to do here, say Y. 645 646config RISCV_ISA_ZBB 647 bool "Zbb extension support for bit manipulation instructions" 648 depends on TOOLCHAIN_HAS_ZBB 649 depends on RISCV_ALTERNATIVE 650 default y 651 help 652 Adds support to dynamically detect the presence of the ZBB 653 extension (basic bit manipulation) and enable its usage. 654 655 The Zbb extension provides instructions to accelerate a number 656 of bit-specific operations (count bit population, sign extending, 657 bitrotation, etc). 658 659 If you don't know what to do here, say Y. 660 661config TOOLCHAIN_HAS_ZBC 662 bool 663 default y 664 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbc) 665 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbc) 666 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 667 depends on AS_HAS_OPTION_ARCH 668 669config RISCV_ISA_ZBC 670 bool "Zbc extension support for carry-less multiplication instructions" 671 depends on TOOLCHAIN_HAS_ZBC 672 depends on MMU 673 depends on RISCV_ALTERNATIVE 674 default y 675 help 676 Adds support to dynamically detect the presence of the Zbc 677 extension (carry-less multiplication) and enable its usage. 678 679 The Zbc extension could accelerate CRC (cyclic redundancy check) 680 calculations. 681 682 If you don't know what to do here, say Y. 683 684config RISCV_ISA_ZICBOM 685 bool "Zicbom extension support for non-coherent DMA operation" 686 depends on MMU 687 depends on RISCV_ALTERNATIVE 688 default y 689 select RISCV_DMA_NONCOHERENT 690 select DMA_DIRECT_REMAP 691 help 692 Adds support to dynamically detect the presence of the ZICBOM 693 extension (Cache Block Management Operations) and enable its 694 usage. 695 696 The Zicbom extension can be used to handle for example 697 non-coherent DMA support on devices that need it. 698 699 If you don't know what to do here, say Y. 700 701config RISCV_ISA_ZICBOZ 702 bool "Zicboz extension support for faster zeroing of memory" 703 depends on RISCV_ALTERNATIVE 704 default y 705 help 706 Enable the use of the Zicboz extension (cbo.zero instruction) 707 when available. 708 709 The Zicboz extension is used for faster zeroing of memory. 710 711 If you don't know what to do here, say Y. 712 713config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 714 def_bool y 715 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 716 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 717 depends on AS_IS_GNU && AS_VERSION >= 23600 718 help 719 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 720 20191213 version, which moves some instructions from the I extension to 721 the Zicsr and Zifencei extensions. This requires explicitly specifying 722 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 723 and Zifencei are supported in binutils from version 2.36 onwards. 724 To make life easier, and avoid forcing toolchains that default to a 725 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 726 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 727 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 728 729config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 730 def_bool y 731 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 732 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 733 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 734 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 735 help 736 Certain versions of clang and GCC do not support zicsr and zifencei via 737 -march. This option causes an older ISA spec compatible with these older 738 versions of clang and GCC to be passed to GAS, which has the same result 739 as passing zicsr and zifencei to -march. 740 741config FPU 742 bool "FPU support" 743 default y 744 help 745 Say N here if you want to disable all floating-point related procedure 746 in the kernel. 747 748 If you don't know what to do here, say Y. 749 750config IRQ_STACKS 751 bool "Independent irq & softirq stacks" if EXPERT 752 default y 753 select HAVE_IRQ_EXIT_ON_IRQ_STACK 754 select HAVE_SOFTIRQ_ON_OWN_STACK 755 help 756 Add independent irq & softirq stacks for percpu to prevent kernel stack 757 overflows. We may save some memory footprint by disabling IRQ_STACKS. 758 759config THREAD_SIZE_ORDER 760 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 761 range 0 4 762 default 1 if 32BIT && !KASAN 763 default 3 if 64BIT && KASAN 764 default 2 765 help 766 Specify the Pages of thread stack size (from 4KB to 64KB), which also 767 affects irq stack size, which is equal to thread stack size. 768 769config RISCV_MISALIGNED 770 bool 771 select SYSCTL_ARCH_UNALIGN_ALLOW 772 help 773 Embed support for emulating misaligned loads and stores. 774 775choice 776 prompt "Unaligned Accesses Support" 777 default RISCV_PROBE_UNALIGNED_ACCESS 778 help 779 This determines the level of support for unaligned accesses. This 780 information is used by the kernel to perform optimizations. It is also 781 exposed to user space via the hwprobe syscall. The hardware will be 782 probed at boot by default. 783 784config RISCV_PROBE_UNALIGNED_ACCESS 785 bool "Probe for hardware unaligned access support" 786 select RISCV_MISALIGNED 787 help 788 During boot, the kernel will run a series of tests to determine the 789 speed of unaligned accesses. This probing will dynamically determine 790 the speed of unaligned accesses on the underlying system. If unaligned 791 memory accesses trap into the kernel as they are not supported by the 792 system, the kernel will emulate the unaligned accesses to preserve the 793 UABI. 794 795config RISCV_EMULATED_UNALIGNED_ACCESS 796 bool "Emulate unaligned access where system support is missing" 797 select RISCV_MISALIGNED 798 help 799 If unaligned memory accesses trap into the kernel as they are not 800 supported by the system, the kernel will emulate the unaligned 801 accesses to preserve the UABI. When the underlying system does support 802 unaligned accesses, the unaligned accesses are assumed to be slow. 803 804config RISCV_SLOW_UNALIGNED_ACCESS 805 bool "Assume the system supports slow unaligned memory accesses" 806 depends on NONPORTABLE 807 help 808 Assume that the system supports slow unaligned memory accesses. The 809 kernel and userspace programs may not be able to run at all on systems 810 that do not support unaligned memory accesses. 811 812config RISCV_EFFICIENT_UNALIGNED_ACCESS 813 bool "Assume the system supports fast unaligned memory accesses" 814 depends on NONPORTABLE 815 select DCACHE_WORD_ACCESS if MMU 816 select HAVE_EFFICIENT_UNALIGNED_ACCESS 817 help 818 Assume that the system supports fast unaligned memory accesses. When 819 enabled, this option improves the performance of the kernel on such 820 systems. However, the kernel and userspace programs will run much more 821 slowly, or will not be able to run at all, on systems that do not 822 support efficient unaligned memory accesses. 823 824endchoice 825 826source "arch/riscv/Kconfig.vendor" 827 828endmenu # "Platform type" 829 830menu "Kernel features" 831 832source "kernel/Kconfig.hz" 833 834config RISCV_SBI_V01 835 bool "SBI v0.1 support" 836 depends on RISCV_SBI 837 help 838 This config allows kernel to use SBI v0.1 APIs. This will be 839 deprecated in future once legacy M-mode software are no longer in use. 840 841config RISCV_BOOT_SPINWAIT 842 bool "Spinwait booting method" 843 depends on SMP 844 default y if RISCV_SBI_V01 || RISCV_M_MODE 845 help 846 This enables support for booting Linux via spinwait method. In the 847 spinwait method, all cores randomly jump to Linux. One of the cores 848 gets chosen via lottery and all other keep spinning on a percpu 849 variable. This method cannot support CPU hotplug and sparse hartid 850 scheme. It should be only enabled for M-mode Linux or platforms relying 851 on older firmware without SBI HSM extension. All other platforms should 852 rely on ordered booting via SBI HSM extension which gets chosen 853 dynamically at runtime if the firmware supports it. 854 855 Since spinwait is incompatible with sparse hart IDs, it requires 856 NR_CPUS be large enough to contain the physical hart ID of the first 857 hart to enter Linux. 858 859 If unsure what to do here, say N. 860 861config ARCH_SUPPORTS_KEXEC 862 def_bool y 863 864config ARCH_SELECTS_KEXEC 865 def_bool y 866 depends on KEXEC 867 select HOTPLUG_CPU if SMP 868 869config ARCH_SUPPORTS_KEXEC_FILE 870 def_bool 64BIT 871 872config ARCH_SELECTS_KEXEC_FILE 873 def_bool y 874 depends on KEXEC_FILE 875 select HAVE_IMA_KEXEC if IMA 876 select KEXEC_ELF 877 878config ARCH_SUPPORTS_KEXEC_PURGATORY 879 def_bool ARCH_SUPPORTS_KEXEC_FILE 880 881config ARCH_SUPPORTS_CRASH_DUMP 882 def_bool y 883 884config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 885 def_bool CRASH_RESERVE 886 887config COMPAT 888 bool "Kernel support for 32-bit U-mode" 889 default 64BIT 890 depends on 64BIT && MMU 891 help 892 This option enables support for a 32-bit U-mode running under a 64-bit 893 kernel at S-mode. riscv32-specific components such as system calls, 894 the user helper functions (vdso), signal rt_frame functions and the 895 ptrace interface are handled appropriately by the kernel. 896 897 If you want to execute 32-bit userspace applications, say Y. 898 899config PARAVIRT 900 bool "Enable paravirtualization code" 901 depends on RISCV_SBI 902 help 903 This changes the kernel so it can modify itself when it is run 904 under a hypervisor, potentially improving performance significantly 905 over full virtualization. 906 907config PARAVIRT_TIME_ACCOUNTING 908 bool "Paravirtual steal time accounting" 909 depends on PARAVIRT 910 help 911 Select this option to enable fine granularity task steal time 912 accounting. Time spent executing other tasks in parallel with 913 the current vCPU is discounted from the vCPU power. To account for 914 that, there can be a small performance impact. 915 916 If in doubt, say N here. 917 918config RELOCATABLE 919 bool "Build a relocatable kernel" 920 depends on MMU && 64BIT && !XIP_KERNEL 921 select MODULE_SECTIONS if MODULES 922 help 923 This builds a kernel as a Position Independent Executable (PIE), 924 which retains all relocation metadata required to relocate the 925 kernel binary at runtime to a different virtual address than the 926 address it was linked at. 927 Since RISCV uses the RELA relocation format, this requires a 928 relocation pass at runtime even if the kernel is loaded at the 929 same address it was linked at. 930 931 If unsure, say N. 932 933config RANDOMIZE_BASE 934 bool "Randomize the address of the kernel image" 935 select RELOCATABLE 936 depends on MMU && 64BIT && !XIP_KERNEL 937 help 938 Randomizes the virtual address at which the kernel image is 939 loaded, as a security feature that deters exploit attempts 940 relying on knowledge of the location of kernel internals. 941 942 It is the bootloader's job to provide entropy, by passing a 943 random u64 value in /chosen/kaslr-seed at kernel entry. 944 945 When booting via the UEFI stub, it will invoke the firmware's 946 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 947 to the kernel proper. In addition, it will randomise the physical 948 location of the kernel Image as well. 949 950 If unsure, say N. 951 952endmenu # "Kernel features" 953 954menu "Boot options" 955 956config CMDLINE 957 string "Built-in kernel command line" 958 help 959 For most platforms, the arguments for the kernel's command line 960 are provided at run-time, during boot. However, there are cases 961 where either no arguments are being provided or the provided 962 arguments are insufficient or even invalid. 963 964 When that occurs, it is possible to define a built-in command 965 line here and choose how the kernel should use it later on. 966 967choice 968 prompt "Built-in command line usage" 969 depends on CMDLINE != "" 970 default CMDLINE_FALLBACK 971 help 972 Choose how the kernel will handle the provided built-in command 973 line. 974 975config CMDLINE_FALLBACK 976 bool "Use bootloader kernel arguments if available" 977 help 978 Use the built-in command line as fallback in case we get nothing 979 during boot. This is the default behaviour. 980 981config CMDLINE_EXTEND 982 bool "Extend bootloader kernel arguments" 983 help 984 The command-line arguments provided during boot will be 985 appended to the built-in command line. This is useful in 986 cases where the provided arguments are insufficient and 987 you don't want to or cannot modify them. 988 989config CMDLINE_FORCE 990 bool "Always use the default kernel command string" 991 help 992 Always use the built-in command line, even if we get one during 993 boot. This is useful in case you need to override the provided 994 command line on systems where you don't have or want control 995 over it. 996 997endchoice 998 999config EFI_STUB 1000 bool 1001 1002config EFI 1003 bool "UEFI runtime support" 1004 depends on OF && !XIP_KERNEL 1005 depends on MMU 1006 default y 1007 select ARCH_SUPPORTS_ACPI if 64BIT 1008 select EFI_GENERIC_STUB 1009 select EFI_PARAMS_FROM_FDT 1010 select EFI_RUNTIME_WRAPPERS 1011 select EFI_STUB 1012 select LIBFDT 1013 select RISCV_ISA_C 1014 select UCS2_STRING 1015 help 1016 This option provides support for runtime services provided 1017 by UEFI firmware (such as non-volatile variables, realtime 1018 clock, and platform reset). A UEFI stub is also provided to 1019 allow the kernel to be booted as an EFI application. This 1020 is only useful on systems that have UEFI firmware. 1021 1022config DMI 1023 bool "Enable support for SMBIOS (DMI) tables" 1024 depends on EFI 1025 default y 1026 help 1027 This enables SMBIOS/DMI feature for systems. 1028 1029 This option is only useful on systems that have UEFI firmware. 1030 However, even with this option, the resultant kernel should 1031 continue to boot on existing non-UEFI platforms. 1032 1033config CC_HAVE_STACKPROTECTOR_TLS 1034 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 1035 1036config STACKPROTECTOR_PER_TASK 1037 def_bool y 1038 depends on !RANDSTRUCT 1039 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 1040 1041config PHYS_RAM_BASE_FIXED 1042 bool "Explicitly specified physical RAM address" 1043 depends on NONPORTABLE 1044 default n 1045 1046config PHYS_RAM_BASE 1047 hex "Platform Physical RAM address" 1048 depends on PHYS_RAM_BASE_FIXED 1049 default "0x80000000" 1050 help 1051 This is the physical address of RAM in the system. It has to be 1052 explicitly specified to run early relocations of read-write data 1053 from flash to RAM. 1054 1055config XIP_KERNEL 1056 bool "Kernel Execute-In-Place from ROM" 1057 depends on MMU && SPARSEMEM && NONPORTABLE 1058 # This prevents XIP from being enabled by all{yes,mod}config, which 1059 # fail to build since XIP doesn't support large kernels. 1060 depends on !COMPILE_TEST 1061 select PHYS_RAM_BASE_FIXED 1062 help 1063 Execute-In-Place allows the kernel to run from non-volatile storage 1064 directly addressable by the CPU, such as NOR flash. This saves RAM 1065 space since the text section of the kernel is not loaded from flash 1066 to RAM. Read-write sections, such as the data section and stack, 1067 are still copied to RAM. The XIP kernel is not compressed since 1068 it has to run directly from flash, so it will take more space to 1069 store it. The flash address used to link the kernel object files, 1070 and for storing it, is configuration dependent. Therefore, if you 1071 say Y here, you must know the proper physical address where to 1072 store the kernel image depending on your own flash memory usage. 1073 1074 Also note that the make target becomes "make xipImage" rather than 1075 "make zImage" or "make Image". The final kernel binary to put in 1076 ROM memory will be arch/riscv/boot/xipImage. 1077 1078 SPARSEMEM is required because the kernel text and rodata that are 1079 flash resident are not backed by memmap, then any attempt to get 1080 a struct page on those regions will trigger a fault. 1081 1082 If unsure, say N. 1083 1084config XIP_PHYS_ADDR 1085 hex "XIP Kernel Physical Location" 1086 depends on XIP_KERNEL 1087 default "0x21000000" 1088 help 1089 This is the physical address in your flash memory the kernel will 1090 be linked for and stored to. This address is dependent on your 1091 own flash usage. 1092 1093config RISCV_ISA_FALLBACK 1094 bool "Permit falling back to parsing riscv,isa for extension support by default" 1095 default y 1096 help 1097 Parsing the "riscv,isa" devicetree property has been deprecated and 1098 replaced by a list of explicitly defined strings. For compatibility 1099 with existing platforms, the kernel will fall back to parsing the 1100 "riscv,isa" property if the replacements are not found. 1101 1102 Selecting N here will result in a kernel that does not use the 1103 fallback, unless the commandline "riscv_isa_fallback" parameter is 1104 present. 1105 1106 Please see the dt-binding, located at 1107 Documentation/devicetree/bindings/riscv/extensions.yaml for details 1108 on the replacement properties, "riscv,isa-base" and 1109 "riscv,isa-extensions". 1110 1111config BUILTIN_DTB 1112 bool "Built-in device tree" 1113 depends on OF && NONPORTABLE 1114 help 1115 Build a device tree into the Linux image. 1116 This option should be selected if no bootloader is being used. 1117 If unsure, say N. 1118 1119 1120config BUILTIN_DTB_SOURCE 1121 string "Built-in device tree source" 1122 depends on BUILTIN_DTB 1123 help 1124 DTS file path (without suffix, relative to arch/riscv/boot/dts) 1125 for the DTS file that will be used to produce the DTB linked into the 1126 kernel. 1127 1128endmenu # "Boot options" 1129 1130config PORTABLE 1131 bool 1132 default !NONPORTABLE 1133 select EFI 1134 select MMU 1135 select OF 1136 1137config ARCH_PROC_KCORE_TEXT 1138 def_bool y 1139 1140menu "Power management options" 1141 1142source "kernel/power/Kconfig" 1143 1144config ARCH_HIBERNATION_POSSIBLE 1145 def_bool y 1146 1147config ARCH_HIBERNATION_HEADER 1148 def_bool HIBERNATION 1149 1150config ARCH_SUSPEND_POSSIBLE 1151 def_bool y 1152 1153endmenu # "Power management options" 1154 1155menu "CPU Power Management" 1156 1157source "drivers/cpuidle/Kconfig" 1158 1159source "drivers/cpufreq/Kconfig" 1160 1161endmenu # "CPU Power Management" 1162 1163source "arch/riscv/kvm/Kconfig" 1164 1165source "drivers/acpi/Kconfig" 1166