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 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 def_bool y 140 141config STACKTRACE_SUPPORT 142 def_bool y 143 144config TRACE_IRQFLAGS_SUPPORT 145 def_bool y 146 147config GENERIC_BUG 148 def_bool y 149 depends on BUG 150 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 151 152config GENERIC_BUG_RELATIVE_POINTERS 153 bool 154 155config GENERIC_CALIBRATE_DELAY 156 def_bool y 157 158config GENERIC_CSUM 159 def_bool y 160 161config GENERIC_HWEIGHT 162 def_bool y 163 164config FIX_EARLYCON_MEM 165 def_bool MMU 166 167config PGTABLE_LEVELS 168 int 169 default 3 if 64BIT 170 default 2 171 172source "arch/riscv/Kconfig.socs" 173 174menu "Platform type" 175 176choice 177 prompt "Base ISA" 178 default ARCH_RV64I 179 help 180 This selects the base ISA that this kernel will target and must match 181 the target platform. 182 183config ARCH_RV32I 184 bool "RV32I" 185 select 32BIT 186 select GENERIC_LIB_ASHLDI3 187 select GENERIC_LIB_ASHRDI3 188 select GENERIC_LIB_LSHRDI3 189 select GENERIC_LIB_UCMPDI2 190 select MMU 191 192config ARCH_RV64I 193 bool "RV64I" 194 select 64BIT 195 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 196 select HAVE_FUNCTION_TRACER 197 select HAVE_FUNCTION_GRAPH_TRACER 198 select HAVE_FTRACE_MCOUNT_RECORD 199 select HAVE_DYNAMIC_FTRACE if MMU 200 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 201 select SWIOTLB if MMU 202 203endchoice 204 205# We must be able to map all physical memory into the kernel, but the compiler 206# is still a bit more efficient when generating code if it's setup in a manner 207# such that it can only map 2GiB of memory. 208choice 209 prompt "Kernel Code Model" 210 default CMODEL_MEDLOW if 32BIT 211 default CMODEL_MEDANY if 64BIT 212 213 config CMODEL_MEDLOW 214 bool "medium low code model" 215 config CMODEL_MEDANY 216 bool "medium any code model" 217endchoice 218 219config MODULE_SECTIONS 220 bool 221 select HAVE_MOD_ARCH_SPECIFIC 222 223choice 224 prompt "Maximum Physical Memory" 225 default MAXPHYSMEM_2GB if 32BIT 226 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 227 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 228 229 config MAXPHYSMEM_2GB 230 bool "2GiB" 231 config MAXPHYSMEM_128GB 232 depends on 64BIT && CMODEL_MEDANY 233 bool "128GiB" 234endchoice 235 236 237config SMP 238 bool "Symmetric Multi-Processing" 239 help 240 This enables support for systems with more than one CPU. If 241 you say N here, the kernel will run on single and 242 multiprocessor machines, but will use only one CPU of a 243 multiprocessor machine. If you say Y here, the kernel will run 244 on many, but not all, single processor machines. On a single 245 processor machine, the kernel will run faster if you say N 246 here. 247 248 If you don't know what to do here, say N. 249 250config NR_CPUS 251 int "Maximum number of CPUs (2-32)" 252 range 2 32 253 depends on SMP 254 default "8" 255 256config HOTPLUG_CPU 257 bool "Support for hot-pluggable CPUs" 258 depends on SMP 259 select GENERIC_IRQ_MIGRATION 260 help 261 262 Say Y here to experiment with turning CPUs off and on. CPUs 263 can be controlled through /sys/devices/system/cpu. 264 265 Say N if you want to disable CPU hotplug. 266 267choice 268 prompt "CPU Tuning" 269 default TUNE_GENERIC 270 271config TUNE_GENERIC 272 bool "generic" 273 274endchoice 275 276config RISCV_ISA_C 277 bool "Emit compressed instructions when building Linux" 278 default y 279 help 280 Adds "C" to the ISA subsets that the toolchain is allowed to emit 281 when building Linux, which results in compressed instructions in the 282 Linux binary. 283 284 If you don't know what to do here, say Y. 285 286menu "supported PMU type" 287 depends on PERF_EVENTS 288 289config RISCV_BASE_PMU 290 bool "Base Performance Monitoring Unit" 291 def_bool y 292 help 293 A base PMU that serves as a reference implementation and has limited 294 feature of perf. It can run on any RISC-V machines so serves as the 295 fallback, but this option can also be disable to reduce kernel size. 296 297endmenu 298 299config FPU 300 bool "FPU support" 301 default y 302 help 303 Say N here if you want to disable all floating-point related procedure 304 in the kernel. 305 306 If you don't know what to do here, say Y. 307 308endmenu 309 310menu "Kernel features" 311 312source "kernel/Kconfig.hz" 313 314config SECCOMP 315 bool "Enable seccomp to safely compute untrusted bytecode" 316 help 317 This kernel feature is useful for number crunching applications 318 that may need to compute untrusted bytecode during their 319 execution. By using pipes or other transports made available to 320 the process as file descriptors supporting the read/write 321 syscalls, it's possible to isolate those applications in 322 their own address space using seccomp. Once seccomp is 323 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 324 and the task is only allowed to execute a few safe syscalls 325 defined by each seccomp mode. 326 327config RISCV_SBI_V01 328 bool "SBI v0.1 support" 329 default y 330 depends on RISCV_SBI 331 help 332 This config allows kernel to use SBI v0.1 APIs. This will be 333 deprecated in future once legacy M-mode software are no longer in use. 334endmenu 335 336menu "Boot options" 337 338config CMDLINE 339 string "Built-in kernel command line" 340 help 341 For most platforms, the arguments for the kernel's command line 342 are provided at run-time, during boot. However, there are cases 343 where either no arguments are being provided or the provided 344 arguments are insufficient or even invalid. 345 346 When that occurs, it is possible to define a built-in command 347 line here and choose how the kernel should use it later on. 348 349choice 350 prompt "Built-in command line usage" if CMDLINE != "" 351 default CMDLINE_FALLBACK 352 help 353 Choose how the kernel will handle the provided built-in command 354 line. 355 356config CMDLINE_FALLBACK 357 bool "Use bootloader kernel arguments if available" 358 help 359 Use the built-in command line as fallback in case we get nothing 360 during boot. This is the default behaviour. 361 362config CMDLINE_EXTEND 363 bool "Extend bootloader kernel arguments" 364 help 365 The command-line arguments provided during boot will be 366 appended to the built-in command line. This is useful in 367 cases where the provided arguments are insufficient and 368 you don't want to or cannot modify them. 369 370 371config CMDLINE_FORCE 372 bool "Always use the default kernel command string" 373 help 374 Always use the built-in command line, even if we get one during 375 boot. This is useful in case you need to override the provided 376 command line on systems where you don't have or want control 377 over it. 378 379endchoice 380 381endmenu 382 383menu "Power management options" 384 385source "kernel/power/Kconfig" 386 387endmenu 388