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 OF 16 select OF_EARLY_FLATTREE 17 select OF_IRQ 18 select ARCH_HAS_BINFMT_FLAT 19 select ARCH_WANT_FRAME_POINTERS 20 select CLONE_BACKWARDS 21 select COMMON_CLK 22 select GENERIC_CLOCKEVENTS 23 select GENERIC_IRQ_SHOW 24 select GENERIC_PCI_IOMAP 25 select GENERIC_SCHED_CLOCK 26 select GENERIC_STRNCPY_FROM_USER if MMU 27 select GENERIC_STRNLEN_USER if MMU 28 select GENERIC_SMP_IDLE_THREAD 29 select GENERIC_ATOMIC64 if !64BIT 30 select GENERIC_IOREMAP 31 select GENERIC_PTDUMP if MMU 32 select HAVE_ARCH_AUDITSYSCALL 33 select HAVE_ARCH_SECCOMP_FILTER 34 select HAVE_ASM_MODVERSIONS 35 select HAVE_MEMBLOCK_NODE_MAP 36 select HAVE_DMA_CONTIGUOUS if MMU 37 select HAVE_FUTEX_CMPXCHG if FUTEX 38 select HAVE_PERF_EVENTS 39 select HAVE_PERF_REGS 40 select HAVE_PERF_USER_STACK_DUMP 41 select HAVE_SYSCALL_TRACEPOINTS 42 select IRQ_DOMAIN 43 select SPARSE_IRQ 44 select SYSCTL_EXCEPTION_TRACE 45 select HAVE_ARCH_TRACEHOOK 46 select HAVE_PCI 47 select MODULES_USE_ELF_RELA if MODULES 48 select MODULE_SECTIONS if MODULES 49 select THREAD_INFO_IN_TASK 50 select PCI_DOMAINS_GENERIC if PCI 51 select PCI_MSI if PCI 52 select RISCV_TIMER 53 select GENERIC_IRQ_MULTI_HANDLER 54 select GENERIC_ARCH_TOPOLOGY if SMP 55 select ARCH_HAS_PTE_SPECIAL 56 select ARCH_HAS_MMIOWB 57 select ARCH_HAS_DEBUG_VIRTUAL if MMU 58 select HAVE_EBPF_JIT if MMU 59 select EDAC_SUPPORT 60 select ARCH_HAS_GIGANTIC_PAGE 61 select ARCH_HAS_SET_DIRECT_MAP 62 select ARCH_HAS_SET_MEMORY 63 select ARCH_HAS_STRICT_KERNEL_RWX if MMU 64 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 65 select SPARSEMEM_STATIC if 32BIT 66 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 67 select HAVE_ARCH_MMAP_RND_BITS if MMU 68 select ARCH_HAS_GCOV_PROFILE_ALL 69 select HAVE_COPY_THREAD_TLS 70 select HAVE_ARCH_KASAN if MMU && 64BIT 71 72config ARCH_MMAP_RND_BITS_MIN 73 default 18 if 64BIT 74 default 8 75 76# max bits determined by the following formula: 77# VA_BITS - PAGE_SHIFT - 3 78config ARCH_MMAP_RND_BITS_MAX 79 default 24 if 64BIT # SV39 based 80 default 17 81 82# set if we run in machine mode, cleared if we run in supervisor mode 83config RISCV_M_MODE 84 bool 85 default !MMU 86 87# set if we are running in S-mode and can use SBI calls 88config RISCV_SBI 89 bool 90 depends on !RISCV_M_MODE 91 default y 92 93config MMU 94 bool "MMU-based Paged Memory Management Support" 95 default y 96 help 97 Select if you want MMU-based virtualised addressing space 98 support by paged memory management. If unsure, say 'Y'. 99 100config ZONE_DMA32 101 bool 102 default y if 64BIT 103 104config VA_BITS 105 int 106 default 32 if 32BIT 107 default 39 if 64BIT 108 109config PA_BITS 110 int 111 default 34 if 32BIT 112 default 56 if 64BIT 113 114config PAGE_OFFSET 115 hex 116 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB 117 default 0x80000000 if 64BIT && !MMU 118 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 119 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 120 121config ARCH_FLATMEM_ENABLE 122 def_bool y 123 124config ARCH_SPARSEMEM_ENABLE 125 def_bool y 126 depends on MMU 127 select SPARSEMEM_VMEMMAP_ENABLE 128 129config ARCH_SELECT_MEMORY_MODEL 130 def_bool ARCH_SPARSEMEM_ENABLE 131 132config ARCH_WANT_GENERAL_HUGETLB 133 def_bool y 134 135config ARCH_SUPPORTS_DEBUG_PAGEALLOC 136 def_bool y 137 138config SYS_SUPPORTS_HUGETLBFS 139 depends on MMU 140 def_bool y 141 142config STACKTRACE_SUPPORT 143 def_bool y 144 145config TRACE_IRQFLAGS_SUPPORT 146 def_bool y 147 148config GENERIC_BUG 149 def_bool y 150 depends on BUG 151 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 152 153config GENERIC_BUG_RELATIVE_POINTERS 154 bool 155 156config GENERIC_CALIBRATE_DELAY 157 def_bool y 158 159config GENERIC_CSUM 160 def_bool y 161 162config GENERIC_HWEIGHT 163 def_bool y 164 165config FIX_EARLYCON_MEM 166 def_bool MMU 167 168config PGTABLE_LEVELS 169 int 170 default 3 if 64BIT 171 default 2 172 173source "arch/riscv/Kconfig.socs" 174 175menu "Platform type" 176 177choice 178 prompt "Base ISA" 179 default ARCH_RV64I 180 help 181 This selects the base ISA that this kernel will target and must match 182 the target platform. 183 184config ARCH_RV32I 185 bool "RV32I" 186 select 32BIT 187 select GENERIC_LIB_ASHLDI3 188 select GENERIC_LIB_ASHRDI3 189 select GENERIC_LIB_LSHRDI3 190 select GENERIC_LIB_UCMPDI2 191 select MMU 192 193config ARCH_RV64I 194 bool "RV64I" 195 select 64BIT 196 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 197 select HAVE_FUNCTION_TRACER 198 select HAVE_FUNCTION_GRAPH_TRACER 199 select HAVE_FTRACE_MCOUNT_RECORD 200 select HAVE_DYNAMIC_FTRACE if MMU 201 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 202 select SWIOTLB if MMU 203 204endchoice 205 206# We must be able to map all physical memory into the kernel, but the compiler 207# is still a bit more efficient when generating code if it's setup in a manner 208# such that it can only map 2GiB of memory. 209choice 210 prompt "Kernel Code Model" 211 default CMODEL_MEDLOW if 32BIT 212 default CMODEL_MEDANY if 64BIT 213 214 config CMODEL_MEDLOW 215 bool "medium low code model" 216 config CMODEL_MEDANY 217 bool "medium any code model" 218endchoice 219 220config MODULE_SECTIONS 221 bool 222 select HAVE_MOD_ARCH_SPECIFIC 223 224choice 225 prompt "Maximum Physical Memory" 226 default MAXPHYSMEM_2GB if 32BIT 227 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 228 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 229 230 config MAXPHYSMEM_2GB 231 bool "2GiB" 232 config MAXPHYSMEM_128GB 233 depends on 64BIT && CMODEL_MEDANY 234 bool "128GiB" 235endchoice 236 237 238config SMP 239 bool "Symmetric Multi-Processing" 240 help 241 This enables support for systems with more than one CPU. If 242 you say N here, the kernel will run on single and 243 multiprocessor machines, but will use only one CPU of a 244 multiprocessor machine. If you say Y here, the kernel will run 245 on many, but not all, single processor machines. On a single 246 processor machine, the kernel will run faster if you say N 247 here. 248 249 If you don't know what to do here, say N. 250 251config NR_CPUS 252 int "Maximum number of CPUs (2-32)" 253 range 2 32 254 depends on SMP 255 default "8" 256 257config HOTPLUG_CPU 258 bool "Support for hot-pluggable CPUs" 259 depends on SMP 260 select GENERIC_IRQ_MIGRATION 261 help 262 263 Say Y here to experiment with turning CPUs off and on. CPUs 264 can be controlled through /sys/devices/system/cpu. 265 266 Say N if you want to disable CPU hotplug. 267 268choice 269 prompt "CPU Tuning" 270 default TUNE_GENERIC 271 272config TUNE_GENERIC 273 bool "generic" 274 275endchoice 276 277config RISCV_ISA_C 278 bool "Emit compressed instructions when building Linux" 279 default y 280 help 281 Adds "C" to the ISA subsets that the toolchain is allowed to emit 282 when building Linux, which results in compressed instructions in the 283 Linux binary. 284 285 If you don't know what to do here, say Y. 286 287menu "supported PMU type" 288 depends on PERF_EVENTS 289 290config RISCV_BASE_PMU 291 bool "Base Performance Monitoring Unit" 292 def_bool y 293 help 294 A base PMU that serves as a reference implementation and has limited 295 feature of perf. It can run on any RISC-V machines so serves as the 296 fallback, but this option can also be disable to reduce kernel size. 297 298endmenu 299 300config FPU 301 bool "FPU support" 302 default y 303 help 304 Say N here if you want to disable all floating-point related procedure 305 in the kernel. 306 307 If you don't know what to do here, say Y. 308 309endmenu 310 311menu "Kernel features" 312 313source "kernel/Kconfig.hz" 314 315config SECCOMP 316 bool "Enable seccomp to safely compute untrusted bytecode" 317 help 318 This kernel feature is useful for number crunching applications 319 that may need to compute untrusted bytecode during their 320 execution. By using pipes or other transports made available to 321 the process as file descriptors supporting the read/write 322 syscalls, it's possible to isolate those applications in 323 their own address space using seccomp. Once seccomp is 324 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 325 and the task is only allowed to execute a few safe syscalls 326 defined by each seccomp mode. 327 328config RISCV_SBI_V01 329 bool "SBI v0.1 support" 330 default y 331 depends on RISCV_SBI 332 help 333 This config allows kernel to use SBI v0.1 APIs. This will be 334 deprecated in future once legacy M-mode software are no longer in use. 335endmenu 336 337menu "Boot options" 338 339config CMDLINE 340 string "Built-in kernel command line" 341 help 342 For most platforms, the arguments for the kernel's command line 343 are provided at run-time, during boot. However, there are cases 344 where either no arguments are being provided or the provided 345 arguments are insufficient or even invalid. 346 347 When that occurs, it is possible to define a built-in command 348 line here and choose how the kernel should use it later on. 349 350choice 351 prompt "Built-in command line usage" if CMDLINE != "" 352 default CMDLINE_FALLBACK 353 help 354 Choose how the kernel will handle the provided built-in command 355 line. 356 357config CMDLINE_FALLBACK 358 bool "Use bootloader kernel arguments if available" 359 help 360 Use the built-in command line as fallback in case we get nothing 361 during boot. This is the default behaviour. 362 363config CMDLINE_EXTEND 364 bool "Extend bootloader kernel arguments" 365 help 366 The command-line arguments provided during boot will be 367 appended to the built-in command line. This is useful in 368 cases where the provided arguments are insufficient and 369 you don't want to or cannot modify them. 370 371 372config CMDLINE_FORCE 373 bool "Always use the default kernel command string" 374 help 375 Always use the built-in command line, even if we get one during 376 boot. This is useful in case you need to override the provided 377 command line on systems where you don't have or want control 378 over it. 379 380endchoice 381 382endmenu 383 384menu "Power management options" 385 386source "kernel/power/Kconfig" 387 388endmenu 389