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.txt. 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_WANT_FRAME_POINTERS 21 select CLONE_BACKWARDS 22 select COMMON_CLK 23 select GENERIC_CLOCKEVENTS 24 select GENERIC_CPU_DEVICES 25 select GENERIC_IRQ_SHOW 26 select GENERIC_PCI_IOMAP 27 select GENERIC_SCHED_CLOCK 28 select GENERIC_STRNCPY_FROM_USER 29 select GENERIC_STRNLEN_USER 30 select GENERIC_SMP_IDLE_THREAD 31 select GENERIC_ATOMIC64 if !64BIT 32 select HAVE_ARCH_AUDITSYSCALL 33 select HAVE_MEMBLOCK_NODE_MAP 34 select HAVE_DMA_CONTIGUOUS 35 select HAVE_FUTEX_CMPXCHG if FUTEX 36 select HAVE_PERF_EVENTS 37 select HAVE_SYSCALL_TRACEPOINTS 38 select IRQ_DOMAIN 39 select SPARSE_IRQ 40 select SYSCTL_EXCEPTION_TRACE 41 select HAVE_ARCH_TRACEHOOK 42 select HAVE_PCI 43 select MODULES_USE_ELF_RELA if MODULES 44 select MODULE_SECTIONS if MODULES 45 select THREAD_INFO_IN_TASK 46 select PCI_DOMAINS_GENERIC if PCI 47 select PCI_MSI if PCI 48 select RISCV_TIMER 49 select GENERIC_IRQ_MULTI_HANDLER 50 select ARCH_HAS_PTE_SPECIAL 51 select ARCH_HAS_MMIOWB 52 select HAVE_EBPF_JIT if 64BIT 53 54config MMU 55 def_bool y 56 57config ZONE_DMA32 58 bool 59 default y if 64BIT 60 61config PAGE_OFFSET 62 hex 63 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB 64 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 65 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 66 67config STACKTRACE_SUPPORT 68 def_bool y 69 70config TRACE_IRQFLAGS_SUPPORT 71 def_bool y 72 73config GENERIC_BUG 74 def_bool y 75 depends on BUG 76 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 77 78config GENERIC_BUG_RELATIVE_POINTERS 79 bool 80 81config GENERIC_CALIBRATE_DELAY 82 def_bool y 83 84config GENERIC_CSUM 85 def_bool y 86 87config GENERIC_HWEIGHT 88 def_bool y 89 90config FIX_EARLYCON_MEM 91 def_bool y 92 93config PGTABLE_LEVELS 94 int 95 default 3 if 64BIT 96 default 2 97 98menu "Platform type" 99 100choice 101 prompt "Base ISA" 102 default ARCH_RV64I 103 help 104 This selects the base ISA that this kernel will target and must match 105 the target platform. 106 107config ARCH_RV32I 108 bool "RV32I" 109 select 32BIT 110 select GENERIC_LIB_ASHLDI3 111 select GENERIC_LIB_ASHRDI3 112 select GENERIC_LIB_LSHRDI3 113 select GENERIC_LIB_UCMPDI2 114 115config ARCH_RV64I 116 bool "RV64I" 117 select 64BIT 118 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 119 select HAVE_FUNCTION_TRACER 120 select HAVE_FUNCTION_GRAPH_TRACER 121 select HAVE_FTRACE_MCOUNT_RECORD 122 select HAVE_DYNAMIC_FTRACE 123 select HAVE_DYNAMIC_FTRACE_WITH_REGS 124 select SWIOTLB 125 126endchoice 127 128# We must be able to map all physical memory into the kernel, but the compiler 129# is still a bit more efficient when generating code if it's setup in a manner 130# such that it can only map 2GiB of memory. 131choice 132 prompt "Kernel Code Model" 133 default CMODEL_MEDLOW if 32BIT 134 default CMODEL_MEDANY if 64BIT 135 136 config CMODEL_MEDLOW 137 bool "medium low code model" 138 config CMODEL_MEDANY 139 bool "medium any code model" 140endchoice 141 142config MODULE_SECTIONS 143 bool 144 select HAVE_MOD_ARCH_SPECIFIC 145 146choice 147 prompt "Maximum Physical Memory" 148 default MAXPHYSMEM_2GB if 32BIT 149 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 150 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 151 152 config MAXPHYSMEM_2GB 153 bool "2GiB" 154 config MAXPHYSMEM_128GB 155 depends on 64BIT && CMODEL_MEDANY 156 bool "128GiB" 157endchoice 158 159 160config SMP 161 bool "Symmetric Multi-Processing" 162 help 163 This enables support for systems with more than one CPU. If 164 you say N here, the kernel will run on single and 165 multiprocessor machines, but will use only one CPU of a 166 multiprocessor machine. If you say Y here, the kernel will run 167 on many, but not all, single processor machines. On a single 168 processor machine, the kernel will run faster if you say N 169 here. 170 171 If you don't know what to do here, say N. 172 173config NR_CPUS 174 int "Maximum number of CPUs (2-32)" 175 range 2 32 176 depends on SMP 177 default "8" 178 179choice 180 prompt "CPU Tuning" 181 default TUNE_GENERIC 182 183config TUNE_GENERIC 184 bool "generic" 185 186endchoice 187 188config RISCV_ISA_C 189 bool "Emit compressed instructions when building Linux" 190 default y 191 help 192 Adds "C" to the ISA subsets that the toolchain is allowed to emit 193 when building Linux, which results in compressed instructions in the 194 Linux binary. 195 196 If you don't know what to do here, say Y. 197 198menu "supported PMU type" 199 depends on PERF_EVENTS 200 201config RISCV_BASE_PMU 202 bool "Base Performance Monitoring Unit" 203 def_bool y 204 help 205 A base PMU that serves as a reference implementation and has limited 206 feature of perf. It can run on any RISC-V machines so serves as the 207 fallback, but this option can also be disable to reduce kernel size. 208 209endmenu 210 211config FPU 212 bool "FPU support" 213 default y 214 help 215 Say N here if you want to disable all floating-point related procedure 216 in the kernel. 217 218 If you don't know what to do here, say Y. 219 220endmenu 221 222menu "Kernel features" 223 224source "kernel/Kconfig.hz" 225 226endmenu 227 228menu "Boot options" 229 230config CMDLINE 231 string "Built-in kernel command line" 232 help 233 For most platforms, the arguments for the kernel's command line 234 are provided at run-time, during boot. However, there are cases 235 where either no arguments are being provided or the provided 236 arguments are insufficient or even invalid. 237 238 When that occurs, it is possible to define a built-in command 239 line here and choose how the kernel should use it later on. 240 241choice 242 prompt "Built-in command line usage" if CMDLINE != "" 243 default CMDLINE_FALLBACK 244 help 245 Choose how the kernel will handle the provided built-in command 246 line. 247 248config CMDLINE_FALLBACK 249 bool "Use bootloader kernel arguments if available" 250 help 251 Use the built-in command line as fallback in case we get nothing 252 during boot. This is the default behaviour. 253 254config CMDLINE_EXTEND 255 bool "Extend bootloader kernel arguments" 256 help 257 The command-line arguments provided during boot will be 258 appended to the built-in command line. This is useful in 259 cases where the provided arguments are insufficient and 260 you don't want to or cannot modify them. 261 262 263config CMDLINE_FORCE 264 bool "Always use the default kernel command string" 265 help 266 Always use the built-in command line, even if we get one during 267 boot. This is useful in case you need to override the provided 268 command line on systems where you don't have or want control 269 over it. 270 271endchoice 272 273endmenu 274 275menu "Power management options" 276 277source "kernel/power/Kconfig" 278 279endmenu 280