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_HAS_BINFMT_FLAT 18 select ARCH_HAS_DEBUG_VIRTUAL if MMU 19 select ARCH_HAS_DEBUG_WX 20 select ARCH_HAS_GCOV_PROFILE_ALL 21 select ARCH_HAS_GIGANTIC_PAGE 22 select ARCH_HAS_KCOV 23 select ARCH_HAS_MMIOWB 24 select ARCH_HAS_PTE_SPECIAL 25 select ARCH_HAS_SET_DIRECT_MAP 26 select ARCH_HAS_SET_MEMORY 27 select ARCH_HAS_STRICT_KERNEL_RWX if MMU 28 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 29 select ARCH_WANT_FRAME_POINTERS 30 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 31 select CLONE_BACKWARDS 32 select COMMON_CLK 33 select EDAC_SUPPORT 34 select GENERIC_ARCH_TOPOLOGY if SMP 35 select GENERIC_ATOMIC64 if !64BIT 36 select GENERIC_CLOCKEVENTS 37 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO 38 select GENERIC_IOREMAP 39 select GENERIC_IRQ_MULTI_HANDLER 40 select GENERIC_IRQ_SHOW 41 select GENERIC_PCI_IOMAP 42 select GENERIC_PTDUMP if MMU 43 select GENERIC_SCHED_CLOCK 44 select GENERIC_SMP_IDLE_THREAD 45 select GENERIC_STRNCPY_FROM_USER if MMU 46 select GENERIC_STRNLEN_USER if MMU 47 select GENERIC_TIME_VSYSCALL if MMU && 64BIT 48 select HANDLE_DOMAIN_IRQ 49 select HAVE_ARCH_AUDITSYSCALL 50 select HAVE_ARCH_JUMP_LABEL 51 select HAVE_ARCH_JUMP_LABEL_RELATIVE 52 select HAVE_ARCH_KASAN if MMU && 64BIT 53 select HAVE_ARCH_KGDB 54 select HAVE_ARCH_KGDB_QXFER_PKT 55 select HAVE_ARCH_MMAP_RND_BITS if MMU 56 select HAVE_ARCH_SECCOMP_FILTER 57 select HAVE_ARCH_TRACEHOOK 58 select HAVE_ASM_MODVERSIONS 59 select HAVE_CONTEXT_TRACKING 60 select HAVE_COPY_THREAD_TLS 61 select HAVE_DEBUG_KMEMLEAK 62 select HAVE_DMA_CONTIGUOUS if MMU 63 select HAVE_EBPF_JIT if MMU 64 select HAVE_FUTEX_CMPXCHG if FUTEX 65 select HAVE_GCC_PLUGINS 66 select HAVE_GENERIC_VDSO if MMU && 64BIT 67 select HAVE_PCI 68 select HAVE_PERF_EVENTS 69 select HAVE_PERF_REGS 70 select HAVE_PERF_USER_STACK_DUMP 71 select HAVE_STACKPROTECTOR 72 select HAVE_SYSCALL_TRACEPOINTS 73 select IRQ_DOMAIN 74 select MODULES_USE_ELF_RELA if MODULES 75 select MODULE_SECTIONS if MODULES 76 select OF 77 select OF_EARLY_FLATTREE 78 select OF_IRQ 79 select PCI_DOMAINS_GENERIC if PCI 80 select PCI_MSI if PCI 81 select RISCV_INTC 82 select RISCV_TIMER 83 select SPARSEMEM_STATIC if 32BIT 84 select SPARSE_IRQ 85 select SYSCTL_EXCEPTION_TRACE 86 select THREAD_INFO_IN_TASK 87 88config ARCH_MMAP_RND_BITS_MIN 89 default 18 if 64BIT 90 default 8 91 92# max bits determined by the following formula: 93# VA_BITS - PAGE_SHIFT - 3 94config ARCH_MMAP_RND_BITS_MAX 95 default 24 if 64BIT # SV39 based 96 default 17 97 98# set if we run in machine mode, cleared if we run in supervisor mode 99config RISCV_M_MODE 100 bool 101 default !MMU 102 103# set if we are running in S-mode and can use SBI calls 104config RISCV_SBI 105 bool 106 depends on !RISCV_M_MODE 107 default y 108 109config MMU 110 bool "MMU-based Paged Memory Management Support" 111 default y 112 help 113 Select if you want MMU-based virtualised addressing space 114 support by paged memory management. If unsure, say 'Y'. 115 116config ZONE_DMA32 117 bool 118 default y if 64BIT 119 120config VA_BITS 121 int 122 default 32 if 32BIT 123 default 39 if 64BIT 124 125config PA_BITS 126 int 127 default 34 if 32BIT 128 default 56 if 64BIT 129 130config PAGE_OFFSET 131 hex 132 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB 133 default 0x80000000 if 64BIT && !MMU 134 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 135 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 136 137config ARCH_FLATMEM_ENABLE 138 def_bool y 139 140config ARCH_SPARSEMEM_ENABLE 141 def_bool y 142 depends on MMU 143 select SPARSEMEM_VMEMMAP_ENABLE 144 145config ARCH_SELECT_MEMORY_MODEL 146 def_bool ARCH_SPARSEMEM_ENABLE 147 148config ARCH_WANT_GENERAL_HUGETLB 149 def_bool y 150 151config ARCH_SUPPORTS_DEBUG_PAGEALLOC 152 def_bool y 153 154config SYS_SUPPORTS_HUGETLBFS 155 depends on MMU 156 def_bool y 157 158config STACKTRACE_SUPPORT 159 def_bool y 160 161config TRACE_IRQFLAGS_SUPPORT 162 def_bool y 163 164config GENERIC_BUG 165 def_bool y 166 depends on BUG 167 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 168 169config GENERIC_BUG_RELATIVE_POINTERS 170 bool 171 172config GENERIC_CALIBRATE_DELAY 173 def_bool y 174 175config GENERIC_CSUM 176 def_bool y 177 178config GENERIC_HWEIGHT 179 def_bool y 180 181config FIX_EARLYCON_MEM 182 def_bool MMU 183 184config PGTABLE_LEVELS 185 int 186 default 3 if 64BIT 187 default 2 188 189config LOCKDEP_SUPPORT 190 def_bool y 191 192source "arch/riscv/Kconfig.socs" 193 194menu "Platform type" 195 196choice 197 prompt "Base ISA" 198 default ARCH_RV64I 199 help 200 This selects the base ISA that this kernel will target and must match 201 the target platform. 202 203config ARCH_RV32I 204 bool "RV32I" 205 select 32BIT 206 select GENERIC_LIB_ASHLDI3 207 select GENERIC_LIB_ASHRDI3 208 select GENERIC_LIB_LSHRDI3 209 select GENERIC_LIB_UCMPDI2 210 select MMU 211 212config ARCH_RV64I 213 bool "RV64I" 214 select 64BIT 215 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 216 select HAVE_DYNAMIC_FTRACE if MMU 217 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 218 select HAVE_FTRACE_MCOUNT_RECORD 219 select HAVE_FUNCTION_GRAPH_TRACER 220 select HAVE_FUNCTION_TRACER 221 select SWIOTLB if MMU 222 223endchoice 224 225# We must be able to map all physical memory into the kernel, but the compiler 226# is still a bit more efficient when generating code if it's setup in a manner 227# such that it can only map 2GiB of memory. 228choice 229 prompt "Kernel Code Model" 230 default CMODEL_MEDLOW if 32BIT 231 default CMODEL_MEDANY if 64BIT 232 233 config CMODEL_MEDLOW 234 bool "medium low code model" 235 config CMODEL_MEDANY 236 bool "medium any code model" 237endchoice 238 239config MODULE_SECTIONS 240 bool 241 select HAVE_MOD_ARCH_SPECIFIC 242 243choice 244 prompt "Maximum Physical Memory" 245 default MAXPHYSMEM_2GB if 32BIT 246 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 247 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 248 249 config MAXPHYSMEM_2GB 250 bool "2GiB" 251 config MAXPHYSMEM_128GB 252 depends on 64BIT && CMODEL_MEDANY 253 bool "128GiB" 254endchoice 255 256 257config SMP 258 bool "Symmetric Multi-Processing" 259 help 260 This enables support for systems with more than one CPU. If 261 you say N here, the kernel will run on single and 262 multiprocessor machines, but will use only one CPU of a 263 multiprocessor machine. If you say Y here, the kernel will run 264 on many, but not all, single processor machines. On a single 265 processor machine, the kernel will run faster if you say N 266 here. 267 268 If you don't know what to do here, say N. 269 270config NR_CPUS 271 int "Maximum number of CPUs (2-32)" 272 range 2 32 273 depends on SMP 274 default "8" 275 276config HOTPLUG_CPU 277 bool "Support for hot-pluggable CPUs" 278 depends on SMP 279 select GENERIC_IRQ_MIGRATION 280 help 281 282 Say Y here to experiment with turning CPUs off and on. CPUs 283 can be controlled through /sys/devices/system/cpu. 284 285 Say N if you want to disable CPU hotplug. 286 287choice 288 prompt "CPU Tuning" 289 default TUNE_GENERIC 290 291config TUNE_GENERIC 292 bool "generic" 293 294endchoice 295 296config RISCV_ISA_C 297 bool "Emit compressed instructions when building Linux" 298 default y 299 help 300 Adds "C" to the ISA subsets that the toolchain is allowed to emit 301 when building Linux, which results in compressed instructions in the 302 Linux binary. 303 304 If you don't know what to do here, say Y. 305 306menu "supported PMU type" 307 depends on PERF_EVENTS 308 309config RISCV_BASE_PMU 310 bool "Base Performance Monitoring Unit" 311 def_bool y 312 help 313 A base PMU that serves as a reference implementation and has limited 314 feature of perf. It can run on any RISC-V machines so serves as the 315 fallback, but this option can also be disable to reduce kernel size. 316 317endmenu 318 319config FPU 320 bool "FPU support" 321 default y 322 help 323 Say N here if you want to disable all floating-point related procedure 324 in the kernel. 325 326 If you don't know what to do here, say Y. 327 328endmenu 329 330menu "Kernel features" 331 332source "kernel/Kconfig.hz" 333 334config SECCOMP 335 bool "Enable seccomp to safely compute untrusted bytecode" 336 help 337 This kernel feature is useful for number crunching applications 338 that may need to compute untrusted bytecode during their 339 execution. By using pipes or other transports made available to 340 the process as file descriptors supporting the read/write 341 syscalls, it's possible to isolate those applications in 342 their own address space using seccomp. Once seccomp is 343 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 344 and the task is only allowed to execute a few safe syscalls 345 defined by each seccomp mode. 346 347config RISCV_SBI_V01 348 bool "SBI v0.1 support" 349 default y 350 depends on RISCV_SBI 351 help 352 This config allows kernel to use SBI v0.1 APIs. This will be 353 deprecated in future once legacy M-mode software are no longer in use. 354endmenu 355 356menu "Boot options" 357 358config CMDLINE 359 string "Built-in kernel command line" 360 help 361 For most platforms, the arguments for the kernel's command line 362 are provided at run-time, during boot. However, there are cases 363 where either no arguments are being provided or the provided 364 arguments are insufficient or even invalid. 365 366 When that occurs, it is possible to define a built-in command 367 line here and choose how the kernel should use it later on. 368 369choice 370 prompt "Built-in command line usage" if CMDLINE != "" 371 default CMDLINE_FALLBACK 372 help 373 Choose how the kernel will handle the provided built-in command 374 line. 375 376config CMDLINE_FALLBACK 377 bool "Use bootloader kernel arguments if available" 378 help 379 Use the built-in command line as fallback in case we get nothing 380 during boot. This is the default behaviour. 381 382config CMDLINE_EXTEND 383 bool "Extend bootloader kernel arguments" 384 help 385 The command-line arguments provided during boot will be 386 appended to the built-in command line. This is useful in 387 cases where the provided arguments are insufficient and 388 you don't want to or cannot modify them. 389 390 391config CMDLINE_FORCE 392 bool "Always use the default kernel command string" 393 help 394 Always use the built-in command line, even if we get one during 395 boot. This is useful in case you need to override the provided 396 command line on systems where you don't have or want control 397 over it. 398 399endchoice 400 401endmenu 402 403config BUILTIN_DTB 404 def_bool n 405 depends on RISCV_M_MODE 406 depends on OF 407 408menu "Power management options" 409 410source "kernel/power/Kconfig" 411 412endmenu 413