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_SUPPORTS_ATOMIC_RMW 17 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU 18 select ARCH_STACKWALK 19 select ARCH_HAS_BINFMT_FLAT 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 30 select ARCH_HAS_SET_MEMORY 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_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX 35 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 36 select ARCH_SUPPORTS_HUGETLBFS if MMU 37 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 38 select ARCH_WANT_FRAME_POINTERS 39 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 40 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU 41 select CLONE_BACKWARDS 42 select CLINT_TIMER if !MMU 43 select COMMON_CLK 44 select EDAC_SUPPORT 45 select GENERIC_ARCH_TOPOLOGY if SMP 46 select GENERIC_ATOMIC64 if !64BIT 47 select GENERIC_CLOCKEVENTS_BROADCAST if SMP 48 select GENERIC_EARLY_IOREMAP 49 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 50 select GENERIC_IOREMAP 51 select GENERIC_IRQ_MULTI_HANDLER 52 select GENERIC_IRQ_SHOW 53 select GENERIC_LIB_DEVMEM_IS_ALLOWED 54 select GENERIC_PCI_IOMAP 55 select GENERIC_PTDUMP if MMU 56 select GENERIC_SCHED_CLOCK 57 select GENERIC_SMP_IDLE_THREAD 58 select GENERIC_STRNCPY_FROM_USER if MMU 59 select GENERIC_STRNLEN_USER if MMU 60 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 61 select HANDLE_DOMAIN_IRQ 62 select HAVE_ARCH_AUDITSYSCALL 63 select HAVE_ARCH_JUMP_LABEL 64 select HAVE_ARCH_JUMP_LABEL_RELATIVE 65 select HAVE_ARCH_KASAN if MMU && 64BIT 66 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT 67 select HAVE_ARCH_KGDB 68 select HAVE_ARCH_KGDB_QXFER_PKT 69 select HAVE_ARCH_MMAP_RND_BITS if MMU 70 select HAVE_ARCH_SECCOMP_FILTER 71 select HAVE_ARCH_TRACEHOOK 72 select HAVE_ASM_MODVERSIONS 73 select HAVE_CONTEXT_TRACKING 74 select HAVE_DEBUG_KMEMLEAK 75 select HAVE_DMA_CONTIGUOUS if MMU 76 select HAVE_EBPF_JIT if MMU 77 select HAVE_FUNCTION_ERROR_INJECTION 78 select HAVE_FUTEX_CMPXCHG if FUTEX 79 select HAVE_GCC_PLUGINS 80 select HAVE_GENERIC_VDSO if MMU && 64BIT 81 select HAVE_IRQ_TIME_ACCOUNTING 82 select HAVE_KPROBES 83 select HAVE_KPROBES_ON_FTRACE 84 select HAVE_KRETPROBES 85 select HAVE_PCI 86 select HAVE_PERF_EVENTS 87 select HAVE_PERF_REGS 88 select HAVE_PERF_USER_STACK_DUMP 89 select HAVE_REGS_AND_STACK_ACCESS_API 90 select HAVE_STACKPROTECTOR 91 select HAVE_SYSCALL_TRACEPOINTS 92 select IRQ_DOMAIN 93 select MODULES_USE_ELF_RELA if MODULES 94 select MODULE_SECTIONS if MODULES 95 select OF 96 select OF_EARLY_FLATTREE 97 select OF_IRQ 98 select PCI_DOMAINS_GENERIC if PCI 99 select PCI_MSI if PCI 100 select RISCV_INTC 101 select RISCV_TIMER if RISCV_SBI 102 select SPARSE_IRQ 103 select SYSCTL_EXCEPTION_TRACE 104 select THREAD_INFO_IN_TASK 105 select UACCESS_MEMCPY if !MMU 106 107config ARCH_MMAP_RND_BITS_MIN 108 default 18 if 64BIT 109 default 8 110 111# max bits determined by the following formula: 112# VA_BITS - PAGE_SHIFT - 3 113config ARCH_MMAP_RND_BITS_MAX 114 default 24 if 64BIT # SV39 based 115 default 17 116 117# set if we run in machine mode, cleared if we run in supervisor mode 118config RISCV_M_MODE 119 bool 120 default !MMU 121 122# set if we are running in S-mode and can use SBI calls 123config RISCV_SBI 124 bool 125 depends on !RISCV_M_MODE 126 default y 127 128config MMU 129 bool "MMU-based Paged Memory Management Support" 130 default y 131 help 132 Select if you want MMU-based virtualised addressing space 133 support by paged memory management. If unsure, say 'Y'. 134 135config ZONE_DMA32 136 bool 137 default y if 64BIT 138 139config VA_BITS 140 int 141 default 32 if 32BIT 142 default 39 if 64BIT 143 144config PA_BITS 145 int 146 default 34 if 32BIT 147 default 56 if 64BIT 148 149config PAGE_OFFSET 150 hex 151 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB 152 default 0x80000000 if 64BIT && !MMU 153 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 154 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 155 156config ARCH_FLATMEM_ENABLE 157 def_bool !NUMA 158 159config ARCH_SPARSEMEM_ENABLE 160 def_bool y 161 depends on MMU 162 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM 163 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT 164 165config ARCH_SELECT_MEMORY_MODEL 166 def_bool ARCH_SPARSEMEM_ENABLE 167 168config ARCH_WANT_GENERAL_HUGETLB 169 def_bool y 170 171config ARCH_SUPPORTS_UPROBES 172 def_bool y 173 174config STACKTRACE_SUPPORT 175 def_bool y 176 177config TRACE_IRQFLAGS_SUPPORT 178 def_bool y 179 180config GENERIC_BUG 181 def_bool y 182 depends on BUG 183 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 184 185config GENERIC_BUG_RELATIVE_POINTERS 186 bool 187 188config GENERIC_CALIBRATE_DELAY 189 def_bool y 190 191config GENERIC_CSUM 192 def_bool y 193 194config GENERIC_HWEIGHT 195 def_bool y 196 197config FIX_EARLYCON_MEM 198 def_bool MMU 199 200config PGTABLE_LEVELS 201 int 202 default 3 if 64BIT 203 default 2 204 205config LOCKDEP_SUPPORT 206 def_bool y 207 208source "arch/riscv/Kconfig.socs" 209source "arch/riscv/Kconfig.erratas" 210 211menu "Platform type" 212 213choice 214 prompt "Base ISA" 215 default ARCH_RV64I 216 help 217 This selects the base ISA that this kernel will target and must match 218 the target platform. 219 220config ARCH_RV32I 221 bool "RV32I" 222 select 32BIT 223 select GENERIC_LIB_ASHLDI3 224 select GENERIC_LIB_ASHRDI3 225 select GENERIC_LIB_LSHRDI3 226 select GENERIC_LIB_UCMPDI2 227 select MMU 228 229config ARCH_RV64I 230 bool "RV64I" 231 select 64BIT 232 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 233 select HAVE_DYNAMIC_FTRACE if MMU && $(cc-option,-fpatchable-function-entry=8) 234 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 235 select HAVE_FTRACE_MCOUNT_RECORD 236 select HAVE_FUNCTION_GRAPH_TRACER 237 select HAVE_FUNCTION_TRACER 238 select SWIOTLB if MMU 239 240endchoice 241 242# We must be able to map all physical memory into the kernel, but the compiler 243# is still a bit more efficient when generating code if it's setup in a manner 244# such that it can only map 2GiB of memory. 245choice 246 prompt "Kernel Code Model" 247 default CMODEL_MEDLOW if 32BIT 248 default CMODEL_MEDANY if 64BIT 249 250 config CMODEL_MEDLOW 251 bool "medium low code model" 252 config CMODEL_MEDANY 253 bool "medium any code model" 254endchoice 255 256config MODULE_SECTIONS 257 bool 258 select HAVE_MOD_ARCH_SPECIFIC 259 260choice 261 prompt "Maximum Physical Memory" 262 default MAXPHYSMEM_1GB if 32BIT 263 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 264 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 265 266 config MAXPHYSMEM_1GB 267 depends on 32BIT 268 bool "1GiB" 269 config MAXPHYSMEM_2GB 270 depends on 64BIT && CMODEL_MEDLOW 271 bool "2GiB" 272 config MAXPHYSMEM_128GB 273 depends on 64BIT && CMODEL_MEDANY 274 bool "128GiB" 275endchoice 276 277 278config SMP 279 bool "Symmetric Multi-Processing" 280 help 281 This enables support for systems with more than one CPU. If 282 you say N here, the kernel will run on single and 283 multiprocessor machines, but will use only one CPU of a 284 multiprocessor machine. If you say Y here, the kernel will run 285 on many, but not all, single processor machines. On a single 286 processor machine, the kernel will run faster if you say N 287 here. 288 289 If you don't know what to do here, say N. 290 291config NR_CPUS 292 int "Maximum number of CPUs (2-32)" 293 range 2 32 294 depends on SMP 295 default "8" 296 297config HOTPLUG_CPU 298 bool "Support for hot-pluggable CPUs" 299 depends on SMP 300 select GENERIC_IRQ_MIGRATION 301 help 302 303 Say Y here to experiment with turning CPUs off and on. CPUs 304 can be controlled through /sys/devices/system/cpu. 305 306 Say N if you want to disable CPU hotplug. 307 308choice 309 prompt "CPU Tuning" 310 default TUNE_GENERIC 311 312config TUNE_GENERIC 313 bool "generic" 314 315endchoice 316 317# Common NUMA Features 318config NUMA 319 bool "NUMA Memory Allocation and Scheduler Support" 320 depends on SMP && MMU 321 select GENERIC_ARCH_NUMA 322 select OF_NUMA 323 select ARCH_SUPPORTS_NUMA_BALANCING 324 help 325 Enable NUMA (Non-Uniform Memory Access) support. 326 327 The kernel will try to allocate memory used by a CPU on the 328 local memory of the CPU and add some more NUMA awareness to the kernel. 329 330config NODES_SHIFT 331 int "Maximum NUMA Nodes (as a power of 2)" 332 range 1 10 333 default "2" 334 depends on NEED_MULTIPLE_NODES 335 help 336 Specify the maximum number of NUMA Nodes available on the target 337 system. Increases memory reserved to accommodate various tables. 338 339config USE_PERCPU_NUMA_NODE_ID 340 def_bool y 341 depends on NUMA 342 343config NEED_PER_CPU_EMBED_FIRST_CHUNK 344 def_bool y 345 depends on NUMA 346 347config RISCV_ISA_C 348 bool "Emit compressed instructions when building Linux" 349 default y 350 help 351 Adds "C" to the ISA subsets that the toolchain is allowed to emit 352 when building Linux, which results in compressed instructions in the 353 Linux binary. 354 355 If you don't know what to do here, say Y. 356 357menu "supported PMU type" 358 depends on PERF_EVENTS 359 360config RISCV_BASE_PMU 361 bool "Base Performance Monitoring Unit" 362 def_bool y 363 help 364 A base PMU that serves as a reference implementation and has limited 365 feature of perf. It can run on any RISC-V machines so serves as the 366 fallback, but this option can also be disable to reduce kernel size. 367 368endmenu 369 370config FPU 371 bool "FPU support" 372 default y 373 help 374 Say N here if you want to disable all floating-point related procedure 375 in the kernel. 376 377 If you don't know what to do here, say Y. 378 379endmenu 380 381menu "Kernel features" 382 383source "kernel/Kconfig.hz" 384 385config RISCV_SBI_V01 386 bool "SBI v0.1 support" 387 default y 388 depends on RISCV_SBI 389 help 390 This config allows kernel to use SBI v0.1 APIs. This will be 391 deprecated in future once legacy M-mode software are no longer in use. 392 393config KEXEC 394 bool "Kexec system call" 395 select KEXEC_CORE 396 select HOTPLUG_CPU if SMP 397 depends on MMU 398 help 399 kexec is a system call that implements the ability to shutdown your 400 current kernel, and to start another kernel. It is like a reboot 401 but it is independent of the system firmware. And like a reboot 402 you can start any kernel with it, not just Linux. 403 404 The name comes from the similarity to the exec system call. 405 406config CRASH_DUMP 407 bool "Build kdump crash kernel" 408 help 409 Generate crash dump after being started by kexec. This should 410 be normally only set in special crash dump kernels which are 411 loaded in the main kernel with kexec-tools into a specially 412 reserved region and then later executed after a crash by 413 kdump/kexec. 414 415 For more details see Documentation/admin-guide/kdump/kdump.rst 416 417endmenu 418 419menu "Boot options" 420 421config CMDLINE 422 string "Built-in kernel command line" 423 help 424 For most platforms, the arguments for the kernel's command line 425 are provided at run-time, during boot. However, there are cases 426 where either no arguments are being provided or the provided 427 arguments are insufficient or even invalid. 428 429 When that occurs, it is possible to define a built-in command 430 line here and choose how the kernel should use it later on. 431 432choice 433 prompt "Built-in command line usage" if CMDLINE != "" 434 default CMDLINE_FALLBACK 435 help 436 Choose how the kernel will handle the provided built-in command 437 line. 438 439config CMDLINE_FALLBACK 440 bool "Use bootloader kernel arguments if available" 441 help 442 Use the built-in command line as fallback in case we get nothing 443 during boot. This is the default behaviour. 444 445config CMDLINE_EXTEND 446 bool "Extend bootloader kernel arguments" 447 help 448 The command-line arguments provided during boot will be 449 appended to the built-in command line. This is useful in 450 cases where the provided arguments are insufficient and 451 you don't want to or cannot modify them. 452 453 454config CMDLINE_FORCE 455 bool "Always use the default kernel command string" 456 help 457 Always use the built-in command line, even if we get one during 458 boot. This is useful in case you need to override the provided 459 command line on systems where you don't have or want control 460 over it. 461 462endchoice 463 464config EFI_STUB 465 bool 466 467config EFI 468 bool "UEFI runtime support" 469 depends on OF && !XIP_KERNEL 470 select LIBFDT 471 select UCS2_STRING 472 select EFI_PARAMS_FROM_FDT 473 select EFI_STUB 474 select EFI_GENERIC_STUB 475 select EFI_RUNTIME_WRAPPERS 476 select RISCV_ISA_C 477 depends on MMU 478 default y 479 help 480 This option provides support for runtime services provided 481 by UEFI firmware (such as non-volatile variables, realtime 482 clock, and platform reset). A UEFI stub is also provided to 483 allow the kernel to be booted as an EFI application. This 484 is only useful on systems that have UEFI firmware. 485 486config CC_HAVE_STACKPROTECTOR_TLS 487 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0) 488 489config STACKPROTECTOR_PER_TASK 490 def_bool y 491 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS 492 493config PHYS_RAM_BASE_FIXED 494 bool "Explicitly specified physical RAM address" 495 default n 496 497config PHYS_RAM_BASE 498 hex "Platform Physical RAM address" 499 depends on PHYS_RAM_BASE_FIXED 500 default "0x80000000" 501 help 502 This is the physical address of RAM in the system. It has to be 503 explicitly specified to run early relocations of read-write data 504 from flash to RAM. 505 506config XIP_KERNEL 507 bool "Kernel Execute-In-Place from ROM" 508 depends on MMU && SPARSEMEM 509 # This prevents XIP from being enabled by all{yes,mod}config, which 510 # fail to build since XIP doesn't support large kernels. 511 depends on !COMPILE_TEST 512 select PHYS_RAM_BASE_FIXED 513 help 514 Execute-In-Place allows the kernel to run from non-volatile storage 515 directly addressable by the CPU, such as NOR flash. This saves RAM 516 space since the text section of the kernel is not loaded from flash 517 to RAM. Read-write sections, such as the data section and stack, 518 are still copied to RAM. The XIP kernel is not compressed since 519 it has to run directly from flash, so it will take more space to 520 store it. The flash address used to link the kernel object files, 521 and for storing it, is configuration dependent. Therefore, if you 522 say Y here, you must know the proper physical address where to 523 store the kernel image depending on your own flash memory usage. 524 525 Also note that the make target becomes "make xipImage" rather than 526 "make zImage" or "make Image". The final kernel binary to put in 527 ROM memory will be arch/riscv/boot/xipImage. 528 529 SPARSEMEM is required because the kernel text and rodata that are 530 flash resident are not backed by memmap, then any attempt to get 531 a struct page on those regions will trigger a fault. 532 533 If unsure, say N. 534 535config XIP_PHYS_ADDR 536 hex "XIP Kernel Physical Location" 537 depends on XIP_KERNEL 538 default "0x21000000" 539 help 540 This is the physical address in your flash memory the kernel will 541 be linked for and stored to. This address is dependent on your 542 own flash usage. 543 544endmenu 545 546config BUILTIN_DTB 547 bool 548 depends on OF 549 default y if XIP_KERNEL 550 551menu "Power management options" 552 553source "kernel/power/Kconfig" 554 555endmenu 556 557source "drivers/firmware/Kconfig" 558