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 ARCH_CLOCKSOURCE_INIT 16 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 17 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 18 select ARCH_HAS_BINFMT_FLAT 19 select ARCH_HAS_CURRENT_STACK_POINTER 20 select ARCH_HAS_DEBUG_VM_PGTABLE 21 select ARCH_HAS_DEBUG_VIRTUAL if MMU 22 select ARCH_HAS_DEBUG_WX 23 select ARCH_HAS_FORTIFY_SOURCE 24 select ARCH_HAS_GCOV_PROFILE_ALL 25 select ARCH_HAS_GIGANTIC_PAGE 26 select ARCH_HAS_KCOV 27 select ARCH_HAS_MMIOWB 28 select ARCH_HAS_PTE_SPECIAL 29 select ARCH_HAS_SET_DIRECT_MAP if MMU 30 select ARCH_HAS_SET_MEMORY if MMU 31 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL 32 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL 33 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 34 select ARCH_HAS_UBSAN_SANITIZE_ALL 35 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 36 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 37 select ARCH_STACKWALK 38 select ARCH_SUPPORTS_ATOMIC_RMW 39 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 40 select ARCH_SUPPORTS_HUGETLBFS if MMU 41 select ARCH_SUPPORTS_PAGE_TABLE_CHECK 42 select ARCH_USE_MEMTEST 43 select ARCH_USE_QUEUED_RWLOCKS 44 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 45 select ARCH_WANT_FRAME_POINTERS 46 select ARCH_WANT_GENERAL_HUGETLB 47 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 48 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 49 select BUILDTIME_TABLE_SORT if MMU 50 select CLONE_BACKWARDS 51 select CLINT_TIMER if !MMU 52 select COMMON_CLK 53 select CPU_PM if CPU_IDLE 54 select EDAC_SUPPORT 55 select GENERIC_ARCH_TOPOLOGY if SMP 56 select GENERIC_ATOMIC64 if !64BIT 57 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 58 select GENERIC_EARLY_IOREMAP 59 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 60 select GENERIC_IDLE_POLL_SETUP 61 select GENERIC_IOREMAP if MMU 62 select GENERIC_IRQ_MULTI_HANDLER 63 select GENERIC_IRQ_SHOW 64 select GENERIC_IRQ_SHOW_LEVEL 65 select GENERIC_LIB_DEVMEM_IS_ALLOWED 66 select GENERIC_PCI_IOMAP 67 select GENERIC_PTDUMP if MMU 68 select GENERIC_SCHED_CLOCK 69 select GENERIC_SMP_IDLE_THREAD 70 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 71 select GENERIC_VDSO_TIME_NS if HAVE_GENERIC_VDSO 72 select HAVE_ARCH_AUDITSYSCALL 73 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL 74 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL 75 select HAVE_ARCH_KASAN if MMU && 64BIT 76 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 77 select HAVE_ARCH_KFENCE if MMU && 64BIT 78 select HAVE_ARCH_KGDB if !XIP_KERNEL 79 select HAVE_ARCH_KGDB_QXFER_PKT 80 select HAVE_ARCH_MMAP_RND_BITS if MMU 81 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 82 select HAVE_ARCH_SECCOMP_FILTER 83 select HAVE_ARCH_TRACEHOOK 84 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU 85 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 86 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 87 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT 88 select HAVE_ASM_MODVERSIONS 89 select HAVE_CONTEXT_TRACKING 90 select HAVE_DEBUG_KMEMLEAK 91 select HAVE_DMA_CONTIGUOUS if MMU 92 select HAVE_EBPF_JIT if MMU 93 select HAVE_FUNCTION_ERROR_INJECTION 94 select HAVE_GCC_PLUGINS 95 select HAVE_GENERIC_VDSO if MMU && 64BIT 96 select HAVE_IRQ_TIME_ACCOUNTING 97 select HAVE_KPROBES if !XIP_KERNEL 98 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL 99 select HAVE_KRETPROBES if !XIP_KERNEL 100 select HAVE_MOVE_PMD 101 select HAVE_MOVE_PUD 102 select HAVE_PCI 103 select HAVE_PERF_EVENTS 104 select HAVE_PERF_REGS 105 select HAVE_PERF_USER_STACK_DUMP 106 select HAVE_REGS_AND_STACK_ACCESS_API 107 select HAVE_FUNCTION_ARG_ACCESS_API 108 select HAVE_STACKPROTECTOR 109 select HAVE_SYSCALL_TRACEPOINTS 110 select HAVE_RSEQ 111 select IRQ_DOMAIN 112 select IRQ_FORCED_THREADING 113 select MODULES_USE_ELF_RELA if MODULES 114 select MODULE_SECTIONS if MODULES 115 select OF 116 select OF_EARLY_FLATTREE 117 select OF_IRQ 118 select PCI_DOMAINS_GENERIC if PCI 119 select PCI_MSI if PCI 120 select RISCV_INTC 121 select RISCV_TIMER if RISCV_SBI 122 select SPARSE_IRQ 123 select SYSCTL_EXCEPTION_TRACE 124 select THREAD_INFO_IN_TASK 125 select TRACE_IRQFLAGS_SUPPORT 126 select UACCESS_MEMCPY if !MMU 127 select ZONE_DMA32 if 64BIT 128 129config ARCH_MMAP_RND_BITS_MIN 130 default 18 if 64BIT 131 default 8 132 133config ARCH_MMAP_RND_COMPAT_BITS_MIN 134 default 8 135 136# max bits determined by the following formula: 137# VA_BITS - PAGE_SHIFT - 3 138config ARCH_MMAP_RND_BITS_MAX 139 default 24 if 64BIT # SV39 based 140 default 17 141 142config ARCH_MMAP_RND_COMPAT_BITS_MAX 143 default 17 144 145# set if we run in machine mode, cleared if we run in supervisor mode 146config RISCV_M_MODE 147 bool 148 default !MMU 149 150# set if we are running in S-mode and can use SBI calls 151config RISCV_SBI 152 bool 153 depends on !RISCV_M_MODE 154 default y 155 156config MMU 157 bool "MMU-based Paged Memory Management Support" 158 default y 159 help 160 Select if you want MMU-based virtualised addressing space 161 support by paged memory management. If unsure, say 'Y'. 162 163config PAGE_OFFSET 164 hex 165 default 0xC0000000 if 32BIT 166 default 0x80000000 if 64BIT && !MMU 167 default 0xff60000000000000 if 64BIT 168 169config KASAN_SHADOW_OFFSET 170 hex 171 depends on KASAN_GENERIC 172 default 0xdfffffff00000000 if 64BIT 173 default 0xffffffff if 32BIT 174 175config ARCH_FLATMEM_ENABLE 176 def_bool !NUMA 177 178config ARCH_SPARSEMEM_ENABLE 179 def_bool y 180 depends on MMU 181 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 182 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 183 184config ARCH_SELECT_MEMORY_MODEL 185 def_bool ARCH_SPARSEMEM_ENABLE 186 187config ARCH_SUPPORTS_UPROBES 188 def_bool y 189 190config STACKTRACE_SUPPORT 191 def_bool y 192 193config GENERIC_BUG 194 def_bool y 195 depends on BUG 196 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 197 198config GENERIC_BUG_RELATIVE_POINTERS 199 bool 200 201config GENERIC_CALIBRATE_DELAY 202 def_bool y 203 204config GENERIC_CSUM 205 def_bool y 206 207config GENERIC_HWEIGHT 208 def_bool y 209 210config FIX_EARLYCON_MEM 211 def_bool MMU 212 213config PGTABLE_LEVELS 214 int 215 default 5 if 64BIT 216 default 2 217 218config LOCKDEP_SUPPORT 219 def_bool y 220 221source "arch/riscv/Kconfig.socs" 222source "arch/riscv/Kconfig.erratas" 223 224menu "Platform type" 225 226choice 227 prompt "Base ISA" 228 default ARCH_RV64I 229 help 230 This selects the base ISA that this kernel will target and must match 231 the target platform. 232 233config ARCH_RV32I 234 bool "RV32I" 235 select 32BIT 236 select GENERIC_LIB_ASHLDI3 237 select GENERIC_LIB_ASHRDI3 238 select GENERIC_LIB_LSHRDI3 239 select GENERIC_LIB_UCMPDI2 240 select MMU 241 242config ARCH_RV64I 243 bool "RV64I" 244 select 64BIT 245 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 246 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8) 247 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 248 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL 249 select HAVE_FUNCTION_GRAPH_TRACER 250 select HAVE_FUNCTION_TRACER if !XIP_KERNEL 251 select SWIOTLB if MMU 252 253endchoice 254 255# We must be able to map all physical memory into the kernel, but the compiler 256# is still a bit more efficient when generating code if it's setup in a manner 257# such that it can only map 2GiB of memory. 258choice 259 prompt "Kernel Code Model" 260 default CMODEL_MEDLOW if 32BIT 261 default CMODEL_MEDANY if 64BIT 262 263 config CMODEL_MEDLOW 264 bool "medium low code model" 265 config CMODEL_MEDANY 266 bool "medium any code model" 267endchoice 268 269config MODULE_SECTIONS 270 bool 271 select HAVE_MOD_ARCH_SPECIFIC 272 273config SMP 274 bool "Symmetric Multi-Processing" 275 help 276 This enables support for systems with more than one CPU. If 277 you say N here, the kernel will run on single and 278 multiprocessor machines, but will use only one CPU of a 279 multiprocessor machine. If you say Y here, the kernel will run 280 on many, but not all, single processor machines. On a single 281 processor machine, the kernel will run faster if you say N 282 here. 283 284 If you don't know what to do here, say N. 285 286config NR_CPUS 287 int "Maximum number of CPUs (2-32)" 288 range 2 32 289 depends on SMP 290 default "8" 291 292config HOTPLUG_CPU 293 bool "Support for hot-pluggable CPUs" 294 depends on SMP 295 select GENERIC_IRQ_MIGRATION 296 help 297 298 Say Y here to experiment with turning CPUs off and on. CPUs 299 can be controlled through /sys/devices/system/cpu. 300 301 Say N if you want to disable CPU hotplug. 302 303choice 304 prompt "CPU Tuning" 305 default TUNE_GENERIC 306 307config TUNE_GENERIC 308 bool "generic" 309 310endchoice 311 312# Common NUMA Features 313config NUMA 314 bool "NUMA Memory Allocation and Scheduler Support" 315 depends on SMP && MMU 316 select GENERIC_ARCH_NUMA 317 select OF_NUMA 318 select ARCH_SUPPORTS_NUMA_BALANCING 319 select USE_PERCPU_NUMA_NODE_ID 320 select NEED_PER_CPU_EMBED_FIRST_CHUNK 321 help 322 Enable NUMA (Non-Uniform Memory Access) support. 323 324 The kernel will try to allocate memory used by a CPU on the 325 local memory of the CPU and add some more NUMA awareness to the kernel. 326 327config NODES_SHIFT 328 int "Maximum NUMA Nodes (as a power of 2)" 329 range 1 10 330 default "2" 331 depends on NUMA 332 help 333 Specify the maximum number of NUMA Nodes available on the target 334 system. Increases memory reserved to accommodate various tables. 335 336config RISCV_ALTERNATIVE 337 bool 338 depends on !XIP_KERNEL 339 help 340 This Kconfig allows the kernel to automatically patch the 341 errata required by the execution platform at run time. The 342 code patching is performed once in the boot stages. It means 343 that the overhead from this mechanism is just taken once. 344 345config RISCV_ALTERNATIVE_EARLY 346 bool 347 depends on RISCV_ALTERNATIVE 348 help 349 Allows early patching of the kernel for special errata 350 351config RISCV_ISA_C 352 bool "Emit compressed instructions when building Linux" 353 default y 354 help 355 Adds "C" to the ISA subsets that the toolchain is allowed to emit 356 when building Linux, which results in compressed instructions in the 357 Linux binary. 358 359 If you don't know what to do here, say Y. 360 361config RISCV_ISA_SVPBMT 362 bool "SVPBMT extension support" 363 depends on 64BIT && MMU 364 select RISCV_ALTERNATIVE 365 default y 366 help 367 Adds support to dynamically detect the presence of the SVPBMT extension 368 (Supervisor-mode: page-based memory types) and enable its usage. 369 370 The SVPBMT extension is only available on 64Bit cpus. 371 372 If you don't know what to do here, say Y. 373 374config FPU 375 bool "FPU support" 376 default y 377 help 378 Say N here if you want to disable all floating-point related procedure 379 in the kernel. 380 381 If you don't know what to do here, say Y. 382 383endmenu 384 385menu "Kernel features" 386 387source "kernel/Kconfig.hz" 388 389config RISCV_SBI_V01 390 bool "SBI v0.1 support" 391 depends on RISCV_SBI 392 help 393 This config allows kernel to use SBI v0.1 APIs. This will be 394 deprecated in future once legacy M-mode software are no longer in use. 395 396config RISCV_BOOT_SPINWAIT 397 bool "Spinwait booting method" 398 depends on SMP 399 default y if RISCV_SBI_V01 || RISCV_M_MODE 400 help 401 This enables support for booting Linux via spinwait method. In the 402 spinwait method, all cores randomly jump to Linux. One of the cores 403 gets chosen via lottery and all other keep spinning on a percpu 404 variable. This method cannot support CPU hotplug and sparse hartid 405 scheme. It should be only enabled for M-mode Linux or platforms relying 406 on older firmware without SBI HSM extension. All other platforms should 407 rely on ordered booting via SBI HSM extension which gets chosen 408 dynamically at runtime if the firmware supports it. 409 410 Since spinwait is incompatible with sparse hart IDs, it requires 411 NR_CPUS be large enough to contain the physical hart ID of the first 412 hart to enter Linux. 413 414 If unsure what to do here, say N. 415 416config KEXEC 417 bool "Kexec system call" 418 select KEXEC_CORE 419 select HOTPLUG_CPU if SMP 420 depends on MMU 421 help 422 kexec is a system call that implements the ability to shutdown your 423 current kernel, and to start another kernel. It is like a reboot 424 but it is independent of the system firmware. And like a reboot 425 you can start any kernel with it, not just Linux. 426 427 The name comes from the similarity to the exec system call. 428 429config KEXEC_FILE 430 bool "kexec file based systmem call" 431 select KEXEC_CORE 432 select KEXEC_ELF 433 select HAVE_IMA_KEXEC if IMA 434 depends on 64BIT 435 help 436 This is new version of kexec system call. This system call is 437 file based and takes file descriptors as system call argument 438 for kernel and initramfs as opposed to list of segments as 439 accepted by previous system call. 440 441 If you don't know what to do here, say Y. 442 443config ARCH_HAS_KEXEC_PURGATORY 444 def_bool KEXEC_FILE 445 select BUILD_BIN2C 446 depends on CRYPTO=y 447 depends on CRYPTO_SHA256=y 448 449config CRASH_DUMP 450 bool "Build kdump crash kernel" 451 help 452 Generate crash dump after being started by kexec. This should 453 be normally only set in special crash dump kernels which are 454 loaded in the main kernel with kexec-tools into a specially 455 reserved region and then later executed after a crash by 456 kdump/kexec. 457 458 For more details see Documentation/admin-guide/kdump/kdump.rst 459 460config COMPAT 461 bool "Kernel support for 32-bit U-mode" 462 default 64BIT 463 depends on 64BIT && MMU 464 help 465 This option enables support for a 32-bit U-mode running under a 64-bit 466 kernel at S-mode. riscv32-specific components such as system calls, 467 the user helper functions (vdso), signal rt_frame functions and the 468 ptrace interface are handled appropriately by the kernel. 469 470 If you want to execute 32-bit userspace applications, say Y. 471 472endmenu 473 474menu "Boot options" 475 476config CMDLINE 477 string "Built-in kernel command line" 478 help 479 For most platforms, the arguments for the kernel's command line 480 are provided at run-time, during boot. However, there are cases 481 where either no arguments are being provided or the provided 482 arguments are insufficient or even invalid. 483 484 When that occurs, it is possible to define a built-in command 485 line here and choose how the kernel should use it later on. 486 487choice 488 prompt "Built-in command line usage" if CMDLINE != "" 489 default CMDLINE_FALLBACK 490 help 491 Choose how the kernel will handle the provided built-in command 492 line. 493 494config CMDLINE_FALLBACK 495 bool "Use bootloader kernel arguments if available" 496 help 497 Use the built-in command line as fallback in case we get nothing 498 during boot. This is the default behaviour. 499 500config CMDLINE_EXTEND 501 bool "Extend bootloader kernel arguments" 502 help 503 The command-line arguments provided during boot will be 504 appended to the built-in command line. This is useful in 505 cases where the provided arguments are insufficient and 506 you don't want to or cannot modify them. 507 508 509config CMDLINE_FORCE 510 bool "Always use the default kernel command string" 511 help 512 Always use the built-in command line, even if we get one during 513 boot. This is useful in case you need to override the provided 514 command line on systems where you don't have or want control 515 over it. 516 517endchoice 518 519config EFI_STUB 520 bool 521 522config EFI 523 bool "UEFI runtime support" 524 depends on OF && !XIP_KERNEL 525 select LIBFDT 526 select UCS2_STRING 527 select EFI_PARAMS_FROM_FDT 528 select EFI_STUB 529 select EFI_GENERIC_STUB 530 select EFI_RUNTIME_WRAPPERS 531 select RISCV_ISA_C 532 depends on MMU 533 default y 534 help 535 This option provides support for runtime services provided 536 by UEFI firmware (such as non-volatile variables, realtime 537 clock, and platform reset). A UEFI stub is also provided to 538 allow the kernel to be booted as an EFI application. This 539 is only useful on systems that have UEFI firmware. 540 541config CC_HAVE_STACKPROTECTOR_TLS 542 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 543 544config STACKPROTECTOR_PER_TASK 545 def_bool y 546 depends on !RANDSTRUCT 547 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 548 549config PHYS_RAM_BASE_FIXED 550 bool "Explicitly specified physical RAM address" 551 default n 552 553config PHYS_RAM_BASE 554 hex "Platform Physical RAM address" 555 depends on PHYS_RAM_BASE_FIXED 556 default "0x80000000" 557 help 558 This is the physical address of RAM in the system. It has to be 559 explicitly specified to run early relocations of read-write data 560 from flash to RAM. 561 562config XIP_KERNEL 563 bool "Kernel Execute-In-Place from ROM" 564 depends on MMU && SPARSEMEM 565 # This prevents XIP from being enabled by all{yes,mod}config, which 566 # fail to build since XIP doesn't support large kernels. 567 depends on !COMPILE_TEST 568 select PHYS_RAM_BASE_FIXED 569 help 570 Execute-In-Place allows the kernel to run from non-volatile storage 571 directly addressable by the CPU, such as NOR flash. This saves RAM 572 space since the text section of the kernel is not loaded from flash 573 to RAM. Read-write sections, such as the data section and stack, 574 are still copied to RAM. The XIP kernel is not compressed since 575 it has to run directly from flash, so it will take more space to 576 store it. The flash address used to link the kernel object files, 577 and for storing it, is configuration dependent. Therefore, if you 578 say Y here, you must know the proper physical address where to 579 store the kernel image depending on your own flash memory usage. 580 581 Also note that the make target becomes "make xipImage" rather than 582 "make zImage" or "make Image". The final kernel binary to put in 583 ROM memory will be arch/riscv/boot/xipImage. 584 585 SPARSEMEM is required because the kernel text and rodata that are 586 flash resident are not backed by memmap, then any attempt to get 587 a struct page on those regions will trigger a fault. 588 589 If unsure, say N. 590 591config XIP_PHYS_ADDR 592 hex "XIP Kernel Physical Location" 593 depends on XIP_KERNEL 594 default "0x21000000" 595 help 596 This is the physical address in your flash memory the kernel will 597 be linked for and stored to. This address is dependent on your 598 own flash usage. 599 600endmenu 601 602config BUILTIN_DTB 603 bool 604 depends on OF 605 default y if XIP_KERNEL 606 607menu "Power management options" 608 609source "kernel/power/Kconfig" 610 611endmenu 612 613menu "CPU Power Management" 614 615source "drivers/cpuidle/Kconfig" 616 617endmenu 618 619source "arch/riscv/kvm/Kconfig" 620