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_REDUCED_HARDWARE_ONLY if ACPI 17 select ARCH_DMA_DEFAULT_COHERENT 18 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 19 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 20 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 21 select ARCH_HAS_BINFMT_FLAT 22 select ARCH_HAS_CURRENT_STACK_POINTER 23 select ARCH_HAS_DEBUG_VIRTUAL if MMU 24 select ARCH_HAS_DEBUG_VM_PGTABLE 25 select ARCH_HAS_DEBUG_WX 26 select ARCH_HAS_FORTIFY_SOURCE 27 select ARCH_HAS_GCOV_PROFILE_ALL 28 select ARCH_HAS_GIGANTIC_PAGE 29 select ARCH_HAS_KCOV 30 select ARCH_HAS_MMIOWB 31 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 32 select ARCH_HAS_PMEM_API 33 select ARCH_HAS_PTE_SPECIAL 34 select ARCH_HAS_SET_DIRECT_MAP if MMU 35 select ARCH_HAS_SET_MEMORY if MMU 36 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 37 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 38 select ARCH_HAS_SYSCALL_WRAPPER 39 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 40 select ARCH_HAS_UBSAN_SANITIZE_ALL 41 select ARCH_HAS_VDSO_DATA 42 select ARCH_KEEP_MEMBLOCK if ACPI 43 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 44 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 45 select ARCH_STACKWALK 46 select ARCH_SUPPORTS_ATOMIC_RMW 47 select ARCH_SUPPORTS_CFI_CLANG 48 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 49 select ARCH_SUPPORTS_HUGETLBFS if MMU 50 select ARCH_SUPPORTS_PAGE_TABLE_CHECK if MMU 51 select ARCH_SUPPORTS_PER_VMA_LOCK if MMU 52 select ARCH_SUPPORTS_SHADOW_CALL_STACK if HAVE_SHADOW_CALL_STACK 53 select ARCH_USE_MEMTEST 54 select ARCH_USE_QUEUED_RWLOCKS 55 select ARCH_USES_CFI_TRAPS if CFI_CLANG 56 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 57 select ARCH_WANT_FRAME_POINTERS 58 select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT 59 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 60 select ARCH_WANT_LD_ORPHAN_WARN if !XIP_KERNEL 61 select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP 62 select ARCH_WANTS_THP_SWAP if HAVE_ARCH_TRANSPARENT_HUGEPAGE 63 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 64 select BUILDTIME_TABLE_SORT if MMU 65 select CLINT_TIMER if !MMU 66 select CLONE_BACKWARDS 67 select COMMON_CLK 68 select CPU_PM if CPU_IDLE || HIBERNATION 69 select EDAC_SUPPORT 70 select FRAME_POINTER if PERF_EVENTS || (FUNCTION_TRACER && !DYNAMIC_FTRACE) 71 select GENERIC_ARCH_TOPOLOGY 72 select GENERIC_ATOMIC64 if !64BIT 73 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 74 select GENERIC_EARLY_IOREMAP 75 select GENERIC_ENTRY 76 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 77 select GENERIC_IDLE_POLL_SETUP 78 select GENERIC_IOREMAP if MMU 79 select GENERIC_IRQ_IPI if SMP 80 select GENERIC_IRQ_IPI_MUX if SMP 81 select GENERIC_IRQ_MULTI_HANDLER 82 select GENERIC_IRQ_SHOW 83 select GENERIC_IRQ_SHOW_LEVEL 84 select GENERIC_LIB_DEVMEM_IS_ALLOWED 85 select GENERIC_PCI_IOMAP 86 select GENERIC_PTDUMP if MMU 87 select GENERIC_SCHED_CLOCK 88 select GENERIC_SMP_IDLE_THREAD 89 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 90 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 91 select HARDIRQS_SW_RESEND 92 select HAS_IOPORT if MMU 93 select HAVE_ARCH_AUDITSYSCALL 94 select HAVE_ARCH_HUGE_VMALLOC if HAVE_ARCH_HUGE_VMAP 95 select HAVE_ARCH_HUGE_VMAP if MMU && 64BIT && !XIP_KERNEL 96 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 97 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 98 select HAVE_ARCH_KASAN if MMU && 64BIT 99 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 100 select HAVE_ARCH_KFENCE if MMU && 64BIT 101 select HAVE_ARCH_KGDB if !XIP_KERNEL 102 select HAVE_ARCH_KGDB_QXFER_PKT 103 select HAVE_ARCH_MMAP_RND_BITS if MMU 104 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 105 select HAVE_ARCH_SECCOMP_FILTER 106 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 107 select HAVE_ARCH_TRACEHOOK 108 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 109 select HAVE_ARCH_USERFAULTFD_MINOR if 64BIT && USERFAULTFD 110 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 111 select HAVE_ASM_MODVERSIONS 112 select HAVE_CONTEXT_TRACKING_USER 113 select HAVE_DEBUG_KMEMLEAK 114 select HAVE_DMA_CONTIGUOUS if MMU 115 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) 116 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 117 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 118 select HAVE_FUNCTION_GRAPH_TRACER 119 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER 120 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION 121 select HAVE_EBPF_JIT if MMU 122 select HAVE_FUNCTION_ARG_ACCESS_API 123 select HAVE_FUNCTION_ERROR_INJECTION 124 select HAVE_GCC_PLUGINS 125 select HAVE_GENERIC_VDSO if MMU && 64BIT 126 select HAVE_IRQ_TIME_ACCOUNTING 127 select HAVE_KPROBES if !XIP_KERNEL 128 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL 129 select HAVE_KRETPROBES if !XIP_KERNEL 130 # https://github.com/ClangBuiltLinux/linux/issues/1881 131 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if !LD_IS_LLD 132 select HAVE_MOVE_PMD 133 select HAVE_MOVE_PUD 134 select HAVE_PCI 135 select HAVE_PERF_EVENTS 136 select HAVE_PERF_REGS 137 select HAVE_PERF_USER_STACK_DUMP 138 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 139 select HAVE_PREEMPT_DYNAMIC_KEY if !XIP_KERNEL 140 select HAVE_REGS_AND_STACK_ACCESS_API 141 select HAVE_RETHOOK if !XIP_KERNEL 142 select HAVE_RSEQ 143 select HAVE_STACKPROTECTOR 144 select HAVE_SYSCALL_TRACEPOINTS 145 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 146 select IRQ_DOMAIN 147 select IRQ_FORCED_THREADING 148 select KASAN_VMALLOC if KASAN 149 select LOCK_MM_AND_FIND_VMA 150 select MODULES_USE_ELF_RELA if MODULES 151 select MODULE_SECTIONS if MODULES 152 select OF 153 select OF_EARLY_FLATTREE 154 select OF_IRQ 155 select PCI_DOMAINS_GENERIC if PCI 156 select PCI_MSI if PCI 157 select RISCV_ALTERNATIVE if !XIP_KERNEL 158 select RISCV_INTC 159 select RISCV_TIMER if RISCV_SBI 160 select SIFIVE_PLIC 161 select SPARSE_IRQ 162 select SYSCTL_EXCEPTION_TRACE 163 select THREAD_INFO_IN_TASK 164 select TRACE_IRQFLAGS_SUPPORT 165 select UACCESS_MEMCPY if !MMU 166 select ZONE_DMA32 if 64BIT 167 168config CLANG_SUPPORTS_DYNAMIC_FTRACE 169 def_bool CC_IS_CLANG 170 # https://github.com/llvm/llvm-project/commit/6ab8927931851bb42b2c93a00801dc499d7d9b1e 171 depends on CLANG_VERSION >= 130000 172 # https://github.com/ClangBuiltLinux/linux/issues/1817 173 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 174 175config GCC_SUPPORTS_DYNAMIC_FTRACE 176 def_bool CC_IS_GCC 177 depends on $(cc-option,-fpatchable-function-entry=8) 178 179config HAVE_SHADOW_CALL_STACK 180 def_bool $(cc-option,-fsanitize=shadow-call-stack) 181 # https://github.com/riscv-non-isa/riscv-elf-psabi-doc/commit/a484e843e6eeb51f0cb7b8819e50da6d2444d769 182 depends on $(ld-option,--no-relax-gp) 183 184config ARCH_MMAP_RND_BITS_MIN 185 default 18 if 64BIT 186 default 8 187 188config ARCH_MMAP_RND_COMPAT_BITS_MIN 189 default 8 190 191# max bits determined by the following formula: 192# VA_BITS - PAGE_SHIFT - 3 193config ARCH_MMAP_RND_BITS_MAX 194 default 24 if 64BIT # SV39 based 195 default 17 196 197config ARCH_MMAP_RND_COMPAT_BITS_MAX 198 default 17 199 200# set if we run in machine mode, cleared if we run in supervisor mode 201config RISCV_M_MODE 202 bool 203 default !MMU 204 205# set if we are running in S-mode and can use SBI calls 206config RISCV_SBI 207 bool 208 depends on !RISCV_M_MODE 209 default y 210 211config MMU 212 bool "MMU-based Paged Memory Management Support" 213 default y 214 help 215 Select if you want MMU-based virtualised addressing space 216 support by paged memory management. If unsure, say 'Y'. 217 218config PAGE_OFFSET 219 hex 220 default 0xC0000000 if 32BIT && MMU 221 default 0x80000000 if !MMU 222 default 0xff60000000000000 if 64BIT 223 224config KASAN_SHADOW_OFFSET 225 hex 226 depends on KASAN_GENERIC 227 default 0xdfffffff00000000 if 64BIT 228 default 0xffffffff if 32BIT 229 230config ARCH_FLATMEM_ENABLE 231 def_bool !NUMA 232 233config ARCH_SPARSEMEM_ENABLE 234 def_bool y 235 depends on MMU 236 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 237 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 238 239config ARCH_SELECT_MEMORY_MODEL 240 def_bool ARCH_SPARSEMEM_ENABLE 241 242config ARCH_SUPPORTS_UPROBES 243 def_bool y 244 245config STACKTRACE_SUPPORT 246 def_bool y 247 248config GENERIC_BUG 249 def_bool y 250 depends on BUG 251 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 252 253config GENERIC_BUG_RELATIVE_POINTERS 254 bool 255 256config GENERIC_CALIBRATE_DELAY 257 def_bool y 258 259config GENERIC_CSUM 260 def_bool y 261 262config GENERIC_HWEIGHT 263 def_bool y 264 265config FIX_EARLYCON_MEM 266 def_bool MMU 267 268config PGTABLE_LEVELS 269 int 270 default 5 if 64BIT 271 default 2 272 273config LOCKDEP_SUPPORT 274 def_bool y 275 276config RISCV_DMA_NONCOHERENT 277 bool 278 select ARCH_HAS_DMA_PREP_COHERENT 279 select ARCH_HAS_SETUP_DMA_OPS 280 select ARCH_HAS_SYNC_DMA_FOR_CPU 281 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 282 select DMA_BOUNCE_UNALIGNED_KMALLOC if SWIOTLB 283 284config RISCV_NONSTANDARD_CACHE_OPS 285 bool 286 help 287 This enables function pointer support for non-standard noncoherent 288 systems to handle cache management. 289 290config AS_HAS_INSN 291 def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) 292 293config AS_HAS_OPTION_ARCH 294 # https://reviews.llvm.org/D123515 295 def_bool y 296 depends on $(as-instr, .option arch$(comma) +m) 297 depends on !$(as-instr, .option arch$(comma) -i) 298 299source "arch/riscv/Kconfig.socs" 300source "arch/riscv/Kconfig.errata" 301 302menu "Platform type" 303 304config NONPORTABLE 305 bool "Allow configurations that result in non-portable kernels" 306 help 307 RISC-V kernel binaries are compatible between all known systems 308 whenever possible, but there are some use cases that can only be 309 satisfied by configurations that result in kernel binaries that are 310 not portable between systems. 311 312 Selecting N does not guarantee kernels will be portable to all known 313 systems. Selecting any of the options guarded by NONPORTABLE will 314 result in kernel binaries that are unlikely to be portable between 315 systems. 316 317 If unsure, say N. 318 319choice 320 prompt "Base ISA" 321 default ARCH_RV64I 322 help 323 This selects the base ISA that this kernel will target and must match 324 the target platform. 325 326config ARCH_RV32I 327 bool "RV32I" 328 depends on NONPORTABLE 329 select 32BIT 330 select GENERIC_LIB_ASHLDI3 331 select GENERIC_LIB_ASHRDI3 332 select GENERIC_LIB_LSHRDI3 333 select GENERIC_LIB_UCMPDI2 334 335config ARCH_RV64I 336 bool "RV64I" 337 select 64BIT 338 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 339 select SWIOTLB if MMU 340 341endchoice 342 343# We must be able to map all physical memory into the kernel, but the compiler 344# is still a bit more efficient when generating code if it's setup in a manner 345# such that it can only map 2GiB of memory. 346choice 347 prompt "Kernel Code Model" 348 default CMODEL_MEDLOW if 32BIT 349 default CMODEL_MEDANY if 64BIT 350 351 config CMODEL_MEDLOW 352 bool "medium low code model" 353 config CMODEL_MEDANY 354 bool "medium any code model" 355endchoice 356 357config MODULE_SECTIONS 358 bool 359 select HAVE_MOD_ARCH_SPECIFIC 360 361config SMP 362 bool "Symmetric Multi-Processing" 363 help 364 This enables support for systems with more than one CPU. If 365 you say N here, the kernel will run on single and 366 multiprocessor machines, but will use only one CPU of a 367 multiprocessor machine. If you say Y here, the kernel will run 368 on many, but not all, single processor machines. On a single 369 processor machine, the kernel will run faster if you say N 370 here. 371 372 If you don't know what to do here, say N. 373 374config SCHED_MC 375 bool "Multi-core scheduler support" 376 depends on SMP 377 help 378 Multi-core scheduler support improves the CPU scheduler's decision 379 making when dealing with multi-core CPU chips at a cost of slightly 380 increased overhead in some places. If unsure say N here. 381 382config NR_CPUS 383 int "Maximum number of CPUs (2-512)" 384 depends on SMP 385 range 2 512 if !RISCV_SBI_V01 386 range 2 32 if RISCV_SBI_V01 && 32BIT 387 range 2 64 if RISCV_SBI_V01 && 64BIT 388 default "32" if 32BIT 389 default "64" if 64BIT 390 391config HOTPLUG_CPU 392 bool "Support for hot-pluggable CPUs" 393 depends on SMP 394 select GENERIC_IRQ_MIGRATION 395 help 396 397 Say Y here to experiment with turning CPUs off and on. CPUs 398 can be controlled through /sys/devices/system/cpu. 399 400 Say N if you want to disable CPU hotplug. 401 402choice 403 prompt "CPU Tuning" 404 default TUNE_GENERIC 405 406config TUNE_GENERIC 407 bool "generic" 408 409endchoice 410 411# Common NUMA Features 412config NUMA 413 bool "NUMA Memory Allocation and Scheduler Support" 414 depends on SMP && MMU 415 select ARCH_SUPPORTS_NUMA_BALANCING 416 select GENERIC_ARCH_NUMA 417 select NEED_PER_CPU_EMBED_FIRST_CHUNK 418 select OF_NUMA 419 select USE_PERCPU_NUMA_NODE_ID 420 help 421 Enable NUMA (Non-Uniform Memory Access) support. 422 423 The kernel will try to allocate memory used by a CPU on the 424 local memory of the CPU and add some more NUMA awareness to the kernel. 425 426config NODES_SHIFT 427 int "Maximum NUMA Nodes (as a power of 2)" 428 range 1 10 429 default "2" 430 depends on NUMA 431 help 432 Specify the maximum number of NUMA Nodes available on the target 433 system. Increases memory reserved to accommodate various tables. 434 435config RISCV_ALTERNATIVE 436 bool 437 depends on !XIP_KERNEL 438 help 439 This Kconfig allows the kernel to automatically patch the 440 erratum or cpufeature required by the execution platform at run 441 time. The code patching overhead is minimal, as it's only done 442 once at boot and once on each module load. 443 444config RISCV_ALTERNATIVE_EARLY 445 bool 446 depends on RISCV_ALTERNATIVE 447 help 448 Allows early patching of the kernel for special errata 449 450config RISCV_ISA_C 451 bool "Emit compressed instructions when building Linux" 452 default y 453 help 454 Adds "C" to the ISA subsets that the toolchain is allowed to emit 455 when building Linux, which results in compressed instructions in the 456 Linux binary. 457 458 If you don't know what to do here, say Y. 459 460config RISCV_ISA_SVNAPOT 461 bool "Svnapot extension support for supervisor mode NAPOT pages" 462 depends on 64BIT && MMU 463 depends on RISCV_ALTERNATIVE 464 default y 465 help 466 Allow kernel to detect the Svnapot ISA-extension dynamically at boot 467 time and enable its usage. 468 469 The Svnapot extension is used to mark contiguous PTEs as a range 470 of contiguous virtual-to-physical translations for a naturally 471 aligned power-of-2 (NAPOT) granularity larger than the base 4KB page 472 size. When HUGETLBFS is also selected this option unconditionally 473 allocates some memory for each NAPOT page size supported by the kernel. 474 When optimizing for low memory consumption and for platforms without 475 the Svnapot extension, it may be better to say N here. 476 477 If you don't know what to do here, say Y. 478 479config RISCV_ISA_SVPBMT 480 bool "Svpbmt extension support for supervisor mode page-based memory types" 481 depends on 64BIT && MMU 482 depends on RISCV_ALTERNATIVE 483 default y 484 help 485 Adds support to dynamically detect the presence of the Svpbmt 486 ISA-extension (Supervisor-mode: page-based memory types) and 487 enable its usage. 488 489 The memory type for a page contains a combination of attributes 490 that indicate the cacheability, idempotency, and ordering 491 properties for access to that page. 492 493 The Svpbmt extension is only available on 64-bit cpus. 494 495 If you don't know what to do here, say Y. 496 497config TOOLCHAIN_HAS_V 498 bool 499 default y 500 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64iv) 501 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32iv) 502 depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 503 depends on AS_HAS_OPTION_ARCH 504 505config RISCV_ISA_V 506 bool "VECTOR extension support" 507 depends on TOOLCHAIN_HAS_V 508 depends on FPU 509 select DYNAMIC_SIGFRAME 510 default y 511 help 512 Say N here if you want to disable all vector related procedure 513 in the kernel. 514 515 If you don't know what to do here, say Y. 516 517config RISCV_ISA_V_DEFAULT_ENABLE 518 bool "Enable userspace Vector by default" 519 depends on RISCV_ISA_V 520 default y 521 help 522 Say Y here if you want to enable Vector in userspace by default. 523 Otherwise, userspace has to make explicit prctl() call to enable 524 Vector, or enable it via the sysctl interface. 525 526 If you don't know what to do here, say Y. 527 528config TOOLCHAIN_HAS_ZBB 529 bool 530 default y 531 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) 532 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) 533 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 534 depends on AS_HAS_OPTION_ARCH 535 536config RISCV_ISA_ZBB 537 bool "Zbb extension support for bit manipulation instructions" 538 depends on TOOLCHAIN_HAS_ZBB 539 depends on MMU 540 depends on RISCV_ALTERNATIVE 541 default y 542 help 543 Adds support to dynamically detect the presence of the ZBB 544 extension (basic bit manipulation) and enable its usage. 545 546 The Zbb extension provides instructions to accelerate a number 547 of bit-specific operations (count bit population, sign extending, 548 bitrotation, etc). 549 550 If you don't know what to do here, say Y. 551 552config RISCV_ISA_ZICBOM 553 bool "Zicbom extension support for non-coherent DMA operation" 554 depends on MMU 555 depends on RISCV_ALTERNATIVE 556 default y 557 select RISCV_DMA_NONCOHERENT 558 select DMA_DIRECT_REMAP 559 help 560 Adds support to dynamically detect the presence of the ZICBOM 561 extension (Cache Block Management Operations) and enable its 562 usage. 563 564 The Zicbom extension can be used to handle for example 565 non-coherent DMA support on devices that need it. 566 567 If you don't know what to do here, say Y. 568 569config RISCV_ISA_ZICBOZ 570 bool "Zicboz extension support for faster zeroing of memory" 571 depends on MMU 572 depends on RISCV_ALTERNATIVE 573 default y 574 help 575 Enable the use of the Zicboz extension (cbo.zero instruction) 576 when available. 577 578 The Zicboz extension is used for faster zeroing of memory. 579 580 If you don't know what to do here, say Y. 581 582config TOOLCHAIN_HAS_ZIHINTPAUSE 583 bool 584 default y 585 depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause) 586 depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause) 587 depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600 588 589config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 590 def_bool y 591 # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc 592 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=98416dbb0a62579d4a7a4a76bab51b5b52fec2cd 593 depends on AS_IS_GNU && AS_VERSION >= 23600 594 help 595 Binutils-2.38 and GCC-12.1.0 bumped the default ISA spec to the newer 596 20191213 version, which moves some instructions from the I extension to 597 the Zicsr and Zifencei extensions. This requires explicitly specifying 598 Zicsr and Zifencei when binutils >= 2.38 or GCC >= 12.1.0. Zicsr 599 and Zifencei are supported in binutils from version 2.36 onwards. 600 To make life easier, and avoid forcing toolchains that default to a 601 newer ISA spec to version 2.2, relax the check to binutils >= 2.36. 602 For clang < 17 or GCC < 11.3.0, for which this is not possible or need 603 special treatment, this is dealt with in TOOLCHAIN_NEEDS_OLD_ISA_SPEC. 604 605config TOOLCHAIN_NEEDS_OLD_ISA_SPEC 606 def_bool y 607 depends on TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI 608 # https://github.com/llvm/llvm-project/commit/22e199e6afb1263c943c0c0d4498694e15bf8a16 609 # https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d29f5d6ab513c52fd872f532c492e35ae9fd6671 610 depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110300) 611 help 612 Certain versions of clang and GCC do not support zicsr and zifencei via 613 -march. This option causes an older ISA spec compatible with these older 614 versions of clang and GCC to be passed to GAS, which has the same result 615 as passing zicsr and zifencei to -march. 616 617config FPU 618 bool "FPU support" 619 default y 620 help 621 Say N here if you want to disable all floating-point related procedure 622 in the kernel. 623 624 If you don't know what to do here, say Y. 625 626config IRQ_STACKS 627 bool "Independent irq & softirq stacks" if EXPERT 628 default y 629 select HAVE_IRQ_EXIT_ON_IRQ_STACK 630 select HAVE_SOFTIRQ_ON_OWN_STACK 631 help 632 Add independent irq & softirq stacks for percpu to prevent kernel stack 633 overflows. We may save some memory footprint by disabling IRQ_STACKS. 634 635config THREAD_SIZE_ORDER 636 int "Kernel stack size (in power-of-two numbers of page size)" if VMAP_STACK && EXPERT 637 range 0 4 638 default 1 if 32BIT && !KASAN 639 default 3 if 64BIT && KASAN 640 default 2 641 help 642 Specify the Pages of thread stack size (from 4KB to 64KB), which also 643 affects irq stack size, which is equal to thread stack size. 644 645config RISCV_MISALIGNED 646 bool "Support misaligned load/store traps for kernel and userspace" 647 select SYSCTL_ARCH_UNALIGN_ALLOW 648 default y 649 help 650 Say Y here if you want the kernel to embed support for misaligned 651 load/store for both kernel and userspace. When disable, misaligned 652 accesses will generate SIGBUS in userspace and panic in kernel. 653 654endmenu # "Platform type" 655 656menu "Kernel features" 657 658source "kernel/Kconfig.hz" 659 660config RISCV_SBI_V01 661 bool "SBI v0.1 support" 662 depends on RISCV_SBI 663 help 664 This config allows kernel to use SBI v0.1 APIs. This will be 665 deprecated in future once legacy M-mode software are no longer in use. 666 667config RISCV_BOOT_SPINWAIT 668 bool "Spinwait booting method" 669 depends on SMP 670 default y if RISCV_SBI_V01 || RISCV_M_MODE 671 help 672 This enables support for booting Linux via spinwait method. In the 673 spinwait method, all cores randomly jump to Linux. One of the cores 674 gets chosen via lottery and all other keep spinning on a percpu 675 variable. This method cannot support CPU hotplug and sparse hartid 676 scheme. It should be only enabled for M-mode Linux or platforms relying 677 on older firmware without SBI HSM extension. All other platforms should 678 rely on ordered booting via SBI HSM extension which gets chosen 679 dynamically at runtime if the firmware supports it. 680 681 Since spinwait is incompatible with sparse hart IDs, it requires 682 NR_CPUS be large enough to contain the physical hart ID of the first 683 hart to enter Linux. 684 685 If unsure what to do here, say N. 686 687config ARCH_SUPPORTS_KEXEC 688 def_bool y 689 690config ARCH_SELECTS_KEXEC 691 def_bool y 692 depends on KEXEC 693 select HOTPLUG_CPU if SMP 694 695config ARCH_SUPPORTS_KEXEC_FILE 696 def_bool 64BIT 697 698config ARCH_SELECTS_KEXEC_FILE 699 def_bool y 700 depends on KEXEC_FILE 701 select HAVE_IMA_KEXEC if IMA 702 select KEXEC_ELF 703 704config ARCH_SUPPORTS_KEXEC_PURGATORY 705 def_bool KEXEC_FILE 706 depends on CRYPTO=y 707 depends on CRYPTO_SHA256=y 708 709config ARCH_SUPPORTS_CRASH_DUMP 710 def_bool y 711 712config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 713 def_bool CRASH_CORE 714 715config COMPAT 716 bool "Kernel support for 32-bit U-mode" 717 default 64BIT 718 depends on 64BIT && MMU 719 help 720 This option enables support for a 32-bit U-mode running under a 64-bit 721 kernel at S-mode. riscv32-specific components such as system calls, 722 the user helper functions (vdso), signal rt_frame functions and the 723 ptrace interface are handled appropriately by the kernel. 724 725 If you want to execute 32-bit userspace applications, say Y. 726 727config RELOCATABLE 728 bool "Build a relocatable kernel" 729 depends on MMU && 64BIT && !XIP_KERNEL 730 help 731 This builds a kernel as a Position Independent Executable (PIE), 732 which retains all relocation metadata required to relocate the 733 kernel binary at runtime to a different virtual address than the 734 address it was linked at. 735 Since RISCV uses the RELA relocation format, this requires a 736 relocation pass at runtime even if the kernel is loaded at the 737 same address it was linked at. 738 739 If unsure, say N. 740 741config RANDOMIZE_BASE 742 bool "Randomize the address of the kernel image" 743 select RELOCATABLE 744 depends on MMU && 64BIT && !XIP_KERNEL 745 help 746 Randomizes the virtual address at which the kernel image is 747 loaded, as a security feature that deters exploit attempts 748 relying on knowledge of the location of kernel internals. 749 750 It is the bootloader's job to provide entropy, by passing a 751 random u64 value in /chosen/kaslr-seed at kernel entry. 752 753 When booting via the UEFI stub, it will invoke the firmware's 754 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 755 to the kernel proper. In addition, it will randomise the physical 756 location of the kernel Image as well. 757 758 If unsure, say N. 759 760endmenu # "Kernel features" 761 762menu "Boot options" 763 764config CMDLINE 765 string "Built-in kernel command line" 766 help 767 For most platforms, the arguments for the kernel's command line 768 are provided at run-time, during boot. However, there are cases 769 where either no arguments are being provided or the provided 770 arguments are insufficient or even invalid. 771 772 When that occurs, it is possible to define a built-in command 773 line here and choose how the kernel should use it later on. 774 775choice 776 prompt "Built-in command line usage" if CMDLINE != "" 777 default CMDLINE_FALLBACK 778 help 779 Choose how the kernel will handle the provided built-in command 780 line. 781 782config CMDLINE_FALLBACK 783 bool "Use bootloader kernel arguments if available" 784 help 785 Use the built-in command line as fallback in case we get nothing 786 during boot. This is the default behaviour. 787 788config CMDLINE_EXTEND 789 bool "Extend bootloader kernel arguments" 790 help 791 The command-line arguments provided during boot will be 792 appended to the built-in command line. This is useful in 793 cases where the provided arguments are insufficient and 794 you don't want to or cannot modify them. 795 796config CMDLINE_FORCE 797 bool "Always use the default kernel command string" 798 help 799 Always use the built-in command line, even if we get one during 800 boot. This is useful in case you need to override the provided 801 command line on systems where you don't have or want control 802 over it. 803 804endchoice 805 806config EFI_STUB 807 bool 808 809config EFI 810 bool "UEFI runtime support" 811 depends on OF && !XIP_KERNEL 812 depends on MMU 813 default y 814 select ARCH_SUPPORTS_ACPI if 64BIT 815 select EFI_GENERIC_STUB 816 select EFI_PARAMS_FROM_FDT 817 select EFI_RUNTIME_WRAPPERS 818 select EFI_STUB 819 select LIBFDT 820 select RISCV_ISA_C 821 select UCS2_STRING 822 help 823 This option provides support for runtime services provided 824 by UEFI firmware (such as non-volatile variables, realtime 825 clock, and platform reset). A UEFI stub is also provided to 826 allow the kernel to be booted as an EFI application. This 827 is only useful on systems that have UEFI firmware. 828 829config CC_HAVE_STACKPROTECTOR_TLS 830 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 831 832config STACKPROTECTOR_PER_TASK 833 def_bool y 834 depends on !RANDSTRUCT 835 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 836 837config PHYS_RAM_BASE_FIXED 838 bool "Explicitly specified physical RAM address" 839 depends on NONPORTABLE 840 default n 841 842config PHYS_RAM_BASE 843 hex "Platform Physical RAM address" 844 depends on PHYS_RAM_BASE_FIXED 845 default "0x80000000" 846 help 847 This is the physical address of RAM in the system. It has to be 848 explicitly specified to run early relocations of read-write data 849 from flash to RAM. 850 851config XIP_KERNEL 852 bool "Kernel Execute-In-Place from ROM" 853 depends on MMU && SPARSEMEM && NONPORTABLE 854 # This prevents XIP from being enabled by all{yes,mod}config, which 855 # fail to build since XIP doesn't support large kernels. 856 depends on !COMPILE_TEST 857 select PHYS_RAM_BASE_FIXED 858 help 859 Execute-In-Place allows the kernel to run from non-volatile storage 860 directly addressable by the CPU, such as NOR flash. This saves RAM 861 space since the text section of the kernel is not loaded from flash 862 to RAM. Read-write sections, such as the data section and stack, 863 are still copied to RAM. The XIP kernel is not compressed since 864 it has to run directly from flash, so it will take more space to 865 store it. The flash address used to link the kernel object files, 866 and for storing it, is configuration dependent. Therefore, if you 867 say Y here, you must know the proper physical address where to 868 store the kernel image depending on your own flash memory usage. 869 870 Also note that the make target becomes "make xipImage" rather than 871 "make zImage" or "make Image". The final kernel binary to put in 872 ROM memory will be arch/riscv/boot/xipImage. 873 874 SPARSEMEM is required because the kernel text and rodata that are 875 flash resident are not backed by memmap, then any attempt to get 876 a struct page on those regions will trigger a fault. 877 878 If unsure, say N. 879 880config XIP_PHYS_ADDR 881 hex "XIP Kernel Physical Location" 882 depends on XIP_KERNEL 883 default "0x21000000" 884 help 885 This is the physical address in your flash memory the kernel will 886 be linked for and stored to. This address is dependent on your 887 own flash usage. 888 889config RISCV_ISA_FALLBACK 890 bool "Permit falling back to parsing riscv,isa for extension support by default" 891 default y 892 help 893 Parsing the "riscv,isa" devicetree property has been deprecated and 894 replaced by a list of explicitly defined strings. For compatibility 895 with existing platforms, the kernel will fall back to parsing the 896 "riscv,isa" property if the replacements are not found. 897 898 Selecting N here will result in a kernel that does not use the 899 fallback, unless the commandline "riscv_isa_fallback" parameter is 900 present. 901 902 Please see the dt-binding, located at 903 Documentation/devicetree/bindings/riscv/extensions.yaml for details 904 on the replacement properties, "riscv,isa-base" and 905 "riscv,isa-extensions". 906 907endmenu # "Boot options" 908 909config BUILTIN_DTB 910 bool 911 depends on OF && NONPORTABLE 912 default y if XIP_KERNEL 913 914config PORTABLE 915 bool 916 default !NONPORTABLE 917 select EFI 918 select MMU 919 select OF 920 921config ARCH_PROC_KCORE_TEXT 922 def_bool y 923 924menu "Power management options" 925 926source "kernel/power/Kconfig" 927 928# Hibernation is only possible on systems where the SBI implementation has 929# marked its reserved memory as not accessible from, or does not run 930# from the same memory as, Linux 931config ARCH_HIBERNATION_POSSIBLE 932 def_bool NONPORTABLE 933 934config ARCH_HIBERNATION_HEADER 935 def_bool HIBERNATION 936 937config ARCH_SUSPEND_POSSIBLE 938 def_bool y 939 940endmenu # "Power management options" 941 942menu "CPU Power Management" 943 944source "drivers/cpuidle/Kconfig" 945 946source "drivers/cpufreq/Kconfig" 947 948endmenu # "CPU Power Management" 949 950source "arch/riscv/kvm/Kconfig" 951 952source "drivers/acpi/Kconfig" 953