1 # SPDX-License-Identifier: GPL-2.0-only
3 # For a description of the syntax of this configuration file,
4 # see Documentation/kbuild/kconfig-language.txt.
15 # even on 32-bit, physical (and DMA) addresses are > 32-bits
16 select PHYS_ADDR_T_64BIT
18 select OF_EARLY_FLATTREE
20 select ARCH_WANT_FRAME_POINTERS
21 select CLONE_BACKWARDS
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
40 select SYSCTL_EXCEPTION_TRACE
41 select HAVE_ARCH_TRACEHOOK
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
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 select ARCH_HAS_GIGANTIC_PAGE
54 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
65 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
66 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
67 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
69 config ARCH_WANT_GENERAL_HUGETLB
72 config SYS_SUPPORTS_HUGETLBFS
75 config STACKTRACE_SUPPORT
78 config TRACE_IRQFLAGS_SUPPORT
84 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
86 config GENERIC_BUG_RELATIVE_POINTERS
89 config GENERIC_CALIBRATE_DELAY
95 config GENERIC_HWEIGHT
98 config FIX_EARLYCON_MEM
101 config PGTABLE_LEVELS
106 source "arch/riscv/Kconfig.socs"
114 This selects the base ISA that this kernel will target and must match
120 select GENERIC_LIB_ASHLDI3
121 select GENERIC_LIB_ASHRDI3
122 select GENERIC_LIB_LSHRDI3
123 select GENERIC_LIB_UCMPDI2
128 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000
129 select HAVE_FUNCTION_TRACER
130 select HAVE_FUNCTION_GRAPH_TRACER
131 select HAVE_FTRACE_MCOUNT_RECORD
132 select HAVE_DYNAMIC_FTRACE
133 select HAVE_DYNAMIC_FTRACE_WITH_REGS
138 # We must be able to map all physical memory into the kernel, but the compiler
139 # is still a bit more efficient when generating code if it's setup in a manner
140 # such that it can only map 2GiB of memory.
142 prompt "Kernel Code Model"
143 default CMODEL_MEDLOW if 32BIT
144 default CMODEL_MEDANY if 64BIT
147 bool "medium low code model"
149 bool "medium any code model"
152 config MODULE_SECTIONS
154 select HAVE_MOD_ARCH_SPECIFIC
157 prompt "Maximum Physical Memory"
158 default MAXPHYSMEM_2GB if 32BIT
159 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
160 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
162 config MAXPHYSMEM_2GB
164 config MAXPHYSMEM_128GB
165 depends on 64BIT && CMODEL_MEDANY
171 bool "Symmetric Multi-Processing"
173 This enables support for systems with more than one CPU. If
174 you say N here, the kernel will run on single and
175 multiprocessor machines, but will use only one CPU of a
176 multiprocessor machine. If you say Y here, the kernel will run
177 on many, but not all, single processor machines. On a single
178 processor machine, the kernel will run faster if you say N
181 If you don't know what to do here, say N.
184 int "Maximum number of CPUs (2-32)"
199 bool "Emit compressed instructions when building Linux"
202 Adds "C" to the ISA subsets that the toolchain is allowed to emit
203 when building Linux, which results in compressed instructions in the
206 If you don't know what to do here, say Y.
208 menu "supported PMU type"
209 depends on PERF_EVENTS
211 config RISCV_BASE_PMU
212 bool "Base Performance Monitoring Unit"
215 A base PMU that serves as a reference implementation and has limited
216 feature of perf. It can run on any RISC-V machines so serves as the
217 fallback, but this option can also be disable to reduce kernel size.
225 Say N here if you want to disable all floating-point related procedure
228 If you don't know what to do here, say Y.
232 menu "Kernel features"
234 source "kernel/Kconfig.hz"
241 string "Built-in kernel command line"
243 For most platforms, the arguments for the kernel's command line
244 are provided at run-time, during boot. However, there are cases
245 where either no arguments are being provided or the provided
246 arguments are insufficient or even invalid.
248 When that occurs, it is possible to define a built-in command
249 line here and choose how the kernel should use it later on.
252 prompt "Built-in command line usage" if CMDLINE != ""
253 default CMDLINE_FALLBACK
255 Choose how the kernel will handle the provided built-in command
258 config CMDLINE_FALLBACK
259 bool "Use bootloader kernel arguments if available"
261 Use the built-in command line as fallback in case we get nothing
262 during boot. This is the default behaviour.
264 config CMDLINE_EXTEND
265 bool "Extend bootloader kernel arguments"
267 The command-line arguments provided during boot will be
268 appended to the built-in command line. This is useful in
269 cases where the provided arguments are insufficient and
270 you don't want to or cannot modify them.
274 bool "Always use the default kernel command string"
276 Always use the built-in command line, even if we get one during
277 boot. This is useful in case you need to override the provided
278 command line on systems where you don't have or want control
285 menu "Power management options"
287 source "kernel/power/Kconfig"