1# 2# For a description of the syntax of this configuration file, 3# see Documentation/kbuild/kconfig-language.txt. 4# 5 6config 64BIT 7 bool 8 9config 32BIT 10 bool 11 12config RISCV 13 def_bool y 14 # even on 32-bit, physical (and DMA) addresses are > 32-bits 15 select PHYS_ADDR_T_64BIT 16 select OF 17 select OF_EARLY_FLATTREE 18 select OF_IRQ 19 select ARCH_WANT_FRAME_POINTERS 20 select CLONE_BACKWARDS 21 select COMMON_CLK 22 select GENERIC_CLOCKEVENTS 23 select GENERIC_CPU_DEVICES 24 select GENERIC_IRQ_SHOW 25 select GENERIC_PCI_IOMAP 26 select GENERIC_SCHED_CLOCK 27 select GENERIC_STRNCPY_FROM_USER 28 select GENERIC_STRNLEN_USER 29 select GENERIC_SMP_IDLE_THREAD 30 select GENERIC_ATOMIC64 if !64BIT 31 select HAVE_ARCH_AUDITSYSCALL 32 select HAVE_MEMBLOCK_NODE_MAP 33 select HAVE_DMA_CONTIGUOUS 34 select HAVE_FUTEX_CMPXCHG if FUTEX 35 select HAVE_PERF_EVENTS 36 select HAVE_SYSCALL_TRACEPOINTS 37 select IRQ_DOMAIN 38 select SPARSE_IRQ 39 select SYSCTL_EXCEPTION_TRACE 40 select HAVE_ARCH_TRACEHOOK 41 select HAVE_PCI 42 select MODULES_USE_ELF_RELA if MODULES 43 select MODULE_SECTIONS if MODULES 44 select THREAD_INFO_IN_TASK 45 select PCI_DOMAINS_GENERIC if PCI 46 select PCI_MSI if PCI 47 select RISCV_TIMER 48 select GENERIC_IRQ_MULTI_HANDLER 49 select ARCH_HAS_PTE_SPECIAL 50 select ARCH_HAS_MMIOWB 51 select HAVE_EBPF_JIT if 64BIT 52 53config MMU 54 def_bool y 55 56config ZONE_DMA32 57 bool 58 default y if 64BIT 59 60config PAGE_OFFSET 61 hex 62 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB 63 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB 64 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB 65 66config STACKTRACE_SUPPORT 67 def_bool y 68 69config TRACE_IRQFLAGS_SUPPORT 70 def_bool y 71 72config GENERIC_BUG 73 def_bool y 74 depends on BUG 75 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT 76 77config GENERIC_BUG_RELATIVE_POINTERS 78 bool 79 80config GENERIC_CALIBRATE_DELAY 81 def_bool y 82 83config GENERIC_CSUM 84 def_bool y 85 86config GENERIC_HWEIGHT 87 def_bool y 88 89config FIX_EARLYCON_MEM 90 def_bool y 91 92config PGTABLE_LEVELS 93 int 94 default 3 if 64BIT 95 default 2 96 97menu "Platform type" 98 99choice 100 prompt "Base ISA" 101 default ARCH_RV64I 102 help 103 This selects the base ISA that this kernel will target and must match 104 the target platform. 105 106config ARCH_RV32I 107 bool "RV32I" 108 select 32BIT 109 select GENERIC_LIB_ASHLDI3 110 select GENERIC_LIB_ASHRDI3 111 select GENERIC_LIB_LSHRDI3 112 select GENERIC_LIB_UCMPDI2 113 114config ARCH_RV64I 115 bool "RV64I" 116 select 64BIT 117 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 118 select HAVE_FUNCTION_TRACER 119 select HAVE_FUNCTION_GRAPH_TRACER 120 select HAVE_FTRACE_MCOUNT_RECORD 121 select HAVE_DYNAMIC_FTRACE 122 select HAVE_DYNAMIC_FTRACE_WITH_REGS 123 select SWIOTLB 124 125endchoice 126 127# We must be able to map all physical memory into the kernel, but the compiler 128# is still a bit more efficient when generating code if it's setup in a manner 129# such that it can only map 2GiB of memory. 130choice 131 prompt "Kernel Code Model" 132 default CMODEL_MEDLOW if 32BIT 133 default CMODEL_MEDANY if 64BIT 134 135 config CMODEL_MEDLOW 136 bool "medium low code model" 137 config CMODEL_MEDANY 138 bool "medium any code model" 139endchoice 140 141config MODULE_SECTIONS 142 bool 143 select HAVE_MOD_ARCH_SPECIFIC 144 145choice 146 prompt "Maximum Physical Memory" 147 default MAXPHYSMEM_2GB if 32BIT 148 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW 149 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY 150 151 config MAXPHYSMEM_2GB 152 bool "2GiB" 153 config MAXPHYSMEM_128GB 154 depends on 64BIT && CMODEL_MEDANY 155 bool "128GiB" 156endchoice 157 158 159config SMP 160 bool "Symmetric Multi-Processing" 161 help 162 This enables support for systems with more than one CPU. If 163 you say N here, the kernel will run on single and 164 multiprocessor machines, but will use only one CPU of a 165 multiprocessor machine. If you say Y here, the kernel will run 166 on many, but not all, single processor machines. On a single 167 processor machine, the kernel will run faster if you say N 168 here. 169 170 If you don't know what to do here, say N. 171 172config NR_CPUS 173 int "Maximum number of CPUs (2-32)" 174 range 2 32 175 depends on SMP 176 default "8" 177 178choice 179 prompt "CPU Tuning" 180 default TUNE_GENERIC 181 182config TUNE_GENERIC 183 bool "generic" 184 185endchoice 186 187config RISCV_ISA_C 188 bool "Emit compressed instructions when building Linux" 189 default y 190 help 191 Adds "C" to the ISA subsets that the toolchain is allowed to emit 192 when building Linux, which results in compressed instructions in the 193 Linux binary. 194 195 If you don't know what to do here, say Y. 196 197menu "supported PMU type" 198 depends on PERF_EVENTS 199 200config RISCV_BASE_PMU 201 bool "Base Performance Monitoring Unit" 202 def_bool y 203 help 204 A base PMU that serves as a reference implementation and has limited 205 feature of perf. It can run on any RISC-V machines so serves as the 206 fallback, but this option can also be disable to reduce kernel size. 207 208endmenu 209 210config FPU 211 bool "FPU support" 212 default y 213 help 214 Say N here if you want to disable all floating-point related procedure 215 in the kernel. 216 217 If you don't know what to do here, say Y. 218 219endmenu 220 221menu "Kernel features" 222 223source "kernel/Kconfig.hz" 224 225endmenu 226 227menu "Boot options" 228 229config CMDLINE 230 string "Built-in kernel command line" 231 help 232 For most platforms, the arguments for the kernel's command line 233 are provided at run-time, during boot. However, there are cases 234 where either no arguments are being provided or the provided 235 arguments are insufficient or even invalid. 236 237 When that occurs, it is possible to define a built-in command 238 line here and choose how the kernel should use it later on. 239 240choice 241 prompt "Built-in command line usage" if CMDLINE != "" 242 default CMDLINE_FALLBACK 243 help 244 Choose how the kernel will handle the provided built-in command 245 line. 246 247config CMDLINE_FALLBACK 248 bool "Use bootloader kernel arguments if available" 249 help 250 Use the built-in command line as fallback in case we get nothing 251 during boot. This is the default behaviour. 252 253config CMDLINE_EXTEND 254 bool "Extend bootloader kernel arguments" 255 help 256 The command-line arguments provided during boot will be 257 appended to the built-in command line. This is useful in 258 cases where the provided arguments are insufficient and 259 you don't want to or cannot modify them. 260 261 262config CMDLINE_FORCE 263 bool "Always use the default kernel command string" 264 help 265 Always use the built-in command line, even if we get one during 266 boot. This is useful in case you need to override the provided 267 command line on systems where you don't have or want control 268 over it. 269 270endchoice 271 272endmenu 273 274menu "Power management options" 275 276source "kernel/power/Kconfig" 277 278endmenu 279