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 # even on 32-bit, physical (and DMA) addresses are > 32-bits 16 select PHYS_ADDR_T_64BIT 17 select OF 18 select OF_EARLY_FLATTREE 19 select OF_IRQ 20 select ARCH_HAS_BINFMT_FLAT 21 select ARCH_WANT_FRAME_POINTERS 22 select CLONE_BACKWARDS 23 select COMMON_CLK 24 select GENERIC_CLOCKEVENTS 25 select GENERIC_CPU_DEVICES 26 select GENERIC_IRQ_SHOW 27 select GENERIC_PCI_IOMAP 28 select GENERIC_SCHED_CLOCK 29 select GENERIC_STRNCPY_FROM_USER if MMU 30 select GENERIC_STRNLEN_USER if MMU 31 select GENERIC_SMP_IDLE_THREAD 32 select GENERIC_ATOMIC64 if !64BIT 33 select GENERIC_IOREMAP 34 select HAVE_ARCH_AUDITSYSCALL 35 select HAVE_ARCH_SECCOMP_FILTER 36 select HAVE_ASM_MODVERSIONS 37 select HAVE_MEMBLOCK_NODE_MAP 38 select HAVE_DMA_CONTIGUOUS if MMU 39 select HAVE_FUTEX_CMPXCHG if FUTEX 40 select HAVE_PERF_EVENTS 41 select HAVE_PERF_REGS 42 select HAVE_PERF_USER_STACK_DUMP 43 select HAVE_SYSCALL_TRACEPOINTS 44 select IRQ_DOMAIN 45 select SPARSE_IRQ 46 select SYSCTL_EXCEPTION_TRACE 47 select HAVE_ARCH_TRACEHOOK 48 select HAVE_PCI 49 select MODULES_USE_ELF_RELA if MODULES 50 select MODULE_SECTIONS if MODULES 51 select THREAD_INFO_IN_TASK 52 select PCI_DOMAINS_GENERIC if PCI 53 select PCI_MSI if PCI 54 select RISCV_TIMER 55 select UACCESS_MEMCPY if !MMU 56 select GENERIC_IRQ_MULTI_HANDLER 57 select GENERIC_ARCH_TOPOLOGY if SMP 58 select ARCH_HAS_PTE_SPECIAL 59 select ARCH_HAS_MMIOWB 60 select HAVE_EBPF_JIT if 64BIT 61 select EDAC_SUPPORT 62 select ARCH_HAS_GIGANTIC_PAGE 63 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT 64 select SPARSEMEM_STATIC if 32BIT 65 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU 66 select HAVE_ARCH_MMAP_RND_BITS if MMU 67 select ARCH_HAS_GCOV_PROFILE_ALL 68 69config ARCH_MMAP_RND_BITS_MIN 70 default 18 if 64BIT 71 default 8 72 73# max bits determined by the following formula: 74# VA_BITS - PAGE_SHIFT - 3 75config ARCH_MMAP_RND_BITS_MAX 76 default 24 if 64BIT # SV39 based 77 default 17 78 79# set if we run in machine mode, cleared if we run in supervisor mode 80config RISCV_M_MODE 81 bool 82 default !MMU 83 84# set if we are running in S-mode and can use SBI calls 85config RISCV_SBI 86 bool 87 depends on !RISCV_M_MODE 88 default y 89 90config MMU 91 bool "MMU-based Paged Memory Management Support" 92 default y 93 help 94 Select if you want MMU-based virtualised addressing space 95 support by paged memory management. If unsure, say 'Y'. 96 97config ZONE_DMA32 98 bool 99 default y if 64BIT 100 101config VA_BITS 102 int 103 default 32 if 32BIT 104 default 39 if 64BIT 105 106config PA_BITS 107 int 108 default 34 if 32BIT 109 default 56 if 64BIT 110 111config PAGE_OFFSET 112 hex 113 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB 114 default 0x80000000 if 64BIT && !MMU 115 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 116 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 117 118config ARCH_FLATMEM_ENABLE 119 def_bool y 120 121config ARCH_SPARSEMEM_ENABLE 122 def_bool y 123 select SPARSEMEM_VMEMMAP_ENABLE 124 125config ARCH_SELECT_MEMORY_MODEL 126 def_bool ARCH_SPARSEMEM_ENABLE 127 128config ARCH_WANT_GENERAL_HUGETLB 129 def_bool y 130 131config SYS_SUPPORTS_HUGETLBFS 132 def_bool y 133 134config STACKTRACE_SUPPORT 135 def_bool y 136 137config TRACE_IRQFLAGS_SUPPORT 138 def_bool y 139 140config GENERIC_BUG 141 def_bool y 142 depends on BUG 143 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 144 145config GENERIC_BUG_RELATIVE_POINTERS 146 bool 147 148config GENERIC_CALIBRATE_DELAY 149 def_bool y 150 151config GENERIC_CSUM 152 def_bool y 153 154config GENERIC_HWEIGHT 155 def_bool y 156 157config FIX_EARLYCON_MEM 158 def_bool MMU 159 160config PGTABLE_LEVELS 161 int 162 default 3 if 64BIT 163 default 2 164 165source "arch/riscv/Kconfig.socs" 166 167menu "Platform type" 168 169choice 170 prompt "Base ISA" 171 default ARCH_RV64I 172 help 173 This selects the base ISA that this kernel will target and must match 174 the target platform. 175 176config ARCH_RV32I 177 bool "RV32I" 178 select 32BIT 179 select GENERIC_LIB_ASHLDI3 180 select GENERIC_LIB_ASHRDI3 181 select GENERIC_LIB_LSHRDI3 182 select GENERIC_LIB_UCMPDI2 183 select MMU 184 185config ARCH_RV64I 186 bool "RV64I" 187 select 64BIT 188 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 189 select HAVE_FUNCTION_TRACER 190 select HAVE_FUNCTION_GRAPH_TRACER 191 select HAVE_FTRACE_MCOUNT_RECORD 192 select HAVE_DYNAMIC_FTRACE if MMU 193 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE 194 select SWIOTLB if MMU 195 196endchoice 197 198# We must be able to map all physical memory into the kernel, but the compiler 199# is still a bit more efficient when generating code if it's setup in a manner 200# such that it can only map 2GiB of memory. 201choice 202 prompt "Kernel Code Model" 203 default CMODEL_MEDLOW if 32BIT 204 default CMODEL_MEDANY if 64BIT 205 206 config CMODEL_MEDLOW 207 bool "medium low code model" 208 config CMODEL_MEDANY 209 bool "medium any code model" 210endchoice 211 212config MODULE_SECTIONS 213 bool 214 select HAVE_MOD_ARCH_SPECIFIC 215 216choice 217 prompt "Maximum Physical Memory" 218 default MAXPHYSMEM_2GB if 32BIT 219 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 220 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 221 222 config MAXPHYSMEM_2GB 223 bool "2GiB" 224 config MAXPHYSMEM_128GB 225 depends on 64BIT && CMODEL_MEDANY 226 bool "128GiB" 227endchoice 228 229 230config SMP 231 bool "Symmetric Multi-Processing" 232 help 233 This enables support for systems with more than one CPU. If 234 you say N here, the kernel will run on single and 235 multiprocessor machines, but will use only one CPU of a 236 multiprocessor machine. If you say Y here, the kernel will run 237 on many, but not all, single processor machines. On a single 238 processor machine, the kernel will run faster if you say N 239 here. 240 241 If you don't know what to do here, say N. 242 243config NR_CPUS 244 int "Maximum number of CPUs (2-32)" 245 range 2 32 246 depends on SMP 247 default "8" 248 249choice 250 prompt "CPU Tuning" 251 default TUNE_GENERIC 252 253config TUNE_GENERIC 254 bool "generic" 255 256endchoice 257 258config RISCV_ISA_C 259 bool "Emit compressed instructions when building Linux" 260 default y 261 help 262 Adds "C" to the ISA subsets that the toolchain is allowed to emit 263 when building Linux, which results in compressed instructions in the 264 Linux binary. 265 266 If you don't know what to do here, say Y. 267 268menu "supported PMU type" 269 depends on PERF_EVENTS 270 271config RISCV_BASE_PMU 272 bool "Base Performance Monitoring Unit" 273 def_bool y 274 help 275 A base PMU that serves as a reference implementation and has limited 276 feature of perf. It can run on any RISC-V machines so serves as the 277 fallback, but this option can also be disable to reduce kernel size. 278 279endmenu 280 281config FPU 282 bool "FPU support" 283 default y 284 help 285 Say N here if you want to disable all floating-point related procedure 286 in the kernel. 287 288 If you don't know what to do here, say Y. 289 290endmenu 291 292menu "Kernel features" 293 294source "kernel/Kconfig.hz" 295 296config SECCOMP 297 bool "Enable seccomp to safely compute untrusted bytecode" 298 help 299 This kernel feature is useful for number crunching applications 300 that may need to compute untrusted bytecode during their 301 execution. By using pipes or other transports made available to 302 the process as file descriptors supporting the read/write 303 syscalls, it's possible to isolate those applications in 304 their own address space using seccomp. Once seccomp is 305 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 306 and the task is only allowed to execute a few safe syscalls 307 defined by each seccomp mode. 308 309endmenu 310 311menu "Boot options" 312 313config CMDLINE 314 string "Built-in kernel command line" 315 help 316 For most platforms, the arguments for the kernel's command line 317 are provided at run-time, during boot. However, there are cases 318 where either no arguments are being provided or the provided 319 arguments are insufficient or even invalid. 320 321 When that occurs, it is possible to define a built-in command 322 line here and choose how the kernel should use it later on. 323 324choice 325 prompt "Built-in command line usage" if CMDLINE != "" 326 default CMDLINE_FALLBACK 327 help 328 Choose how the kernel will handle the provided built-in command 329 line. 330 331config CMDLINE_FALLBACK 332 bool "Use bootloader kernel arguments if available" 333 help 334 Use the built-in command line as fallback in case we get nothing 335 during boot. This is the default behaviour. 336 337config CMDLINE_EXTEND 338 bool "Extend bootloader kernel arguments" 339 help 340 The command-line arguments provided during boot will be 341 appended to the built-in command line. This is useful in 342 cases where the provided arguments are insufficient and 343 you don't want to or cannot modify them. 344 345 346config CMDLINE_FORCE 347 bool "Always use the default kernel command string" 348 help 349 Always use the built-in command line, even if we get one during 350 boot. This is useful in case you need to override the provided 351 command line on systems where you don't have or want control 352 over it. 353 354endchoice 355 356endmenu 357 358menu "Power management options" 359 360source "kernel/power/Kconfig" 361 362endmenu 363