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