2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
14 # even on 32-bit, physical (and DMA) addresses are > 32-bits
15 select PHYS_ADDR_T_64BIT
17 select OF_EARLY_FLATTREE
19 select ARCH_WANT_FRAME_POINTERS
20 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_STRNCPY_FROM_USER
28 select GENERIC_STRNLEN_USER
29 select GENERIC_SMP_IDLE_THREAD
30 select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
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_GENERIC_DMA_COHERENT
36 select HAVE_PERF_EVENTS
38 select RISCV_ISA_A if SMP
40 select SYSCTL_EXCEPTION_TRACE
41 select HAVE_ARCH_TRACEHOOK
42 select MODULES_USE_ELF_RELA if MODULES
43 select THREAD_INFO_IN_TASK
45 select GENERIC_IRQ_MULTI_HANDLER
46 select ARCH_HAS_PTE_SPECIAL
57 default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
58 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
59 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
61 config STACKTRACE_SUPPORT
64 config TRACE_IRQFLAGS_SUPPORT
67 config RWSEM_GENERIC_SPINLOCK
73 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
75 config GENERIC_BUG_RELATIVE_POINTERS
78 config GENERIC_CALIBRATE_DELAY
84 config GENERIC_HWEIGHT
101 This selects the base ISA that this kernel will traget and must match
107 select GENERIC_LIB_ASHLDI3
108 select GENERIC_LIB_ASHRDI3
109 select GENERIC_LIB_LSHRDI3
110 select GENERIC_LIB_UCMPDI2
115 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000
116 select HAVE_FUNCTION_TRACER
117 select HAVE_FUNCTION_GRAPH_TRACER
118 select HAVE_FTRACE_MCOUNT_RECORD
119 select HAVE_DYNAMIC_FTRACE
120 select HAVE_DYNAMIC_FTRACE_WITH_REGS
125 # We must be able to map all physical memory into the kernel, but the compiler
126 # is still a bit more efficient when generating code if it's setup in a manner
127 # such that it can only map 2GiB of memory.
129 prompt "Kernel Code Model"
130 default CMODEL_MEDLOW if 32BIT
131 default CMODEL_MEDANY if 64BIT
134 bool "medium low code model"
136 bool "medium any code model"
139 config MODULE_SECTIONS
141 select HAVE_MOD_ARCH_SPECIFIC
144 prompt "Maximum Physical Memory"
145 default MAXPHYSMEM_2GB if 32BIT
146 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
147 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
149 config MAXPHYSMEM_2GB
151 config MAXPHYSMEM_128GB
152 depends on 64BIT && CMODEL_MEDANY
153 select MODULE_SECTIONS if MODULES
159 bool "Symmetric Multi-Processing"
161 This enables support for systems with more than one CPU. If
162 you say N here, the kernel will run on single and
163 multiprocessor machines, but will use only one CPU of a
164 multiprocessor machine. If you say Y here, the kernel will run
165 on many, but not all, single processor machines. On a single
166 processor machine, the kernel will run faster if you say N
169 If you don't know what to do here, say N.
172 int "Maximum number of CPUs (2-32)"
187 bool "Emit compressed instructions when building Linux"
190 Adds "C" to the ISA subsets that the toolchain is allowed to emit
191 when building Linux, which results in compressed instructions in the
194 If you don't know what to do here, say Y.
199 menu "supported PMU type"
200 depends on PERF_EVENTS
202 config RISCV_BASE_PMU
203 bool "Base Performance Monitoring Unit"
206 A base PMU that serves as a reference implementation and has limited
207 feature of perf. It can run on any RISC-V machines so serves as the
208 fallback, but this option can also be disable to reduce kernel size.
216 Say N here if you want to disable all floating-point related procedure
219 If you don't know what to do here, say Y.
223 menu "Kernel features"
225 source "kernel/Kconfig.hz"
232 bool "Built-in kernel command line"
234 For most platforms, it is firmware or second stage bootloader
235 that by default specifies the kernel command line options.
236 However, it might be necessary or advantageous to either override
237 the default kernel command line or add a few extra options to it.
238 For such cases, this option allows hardcoding command line options
239 directly into the kernel.
241 For that, choose 'Y' here and fill in the extra boot parameters
244 The built-in options will be concatenated to the default command
245 line if CMDLINE_FORCE is set to 'N'. Otherwise, the default
246 command line will be ignored and replaced by the built-in string.
249 string "Built-in kernel command string"
250 depends on CMDLINE_BOOL
253 Supply command-line options at build time by entering them here.
256 bool "Built-in command line overrides bootloader arguments"
257 depends on CMDLINE_BOOL
259 Set this option to 'Y' to have the kernel ignore the bootloader
260 or firmware command line. Instead, the built-in command line
261 will be used exclusively.
263 If you don't know what to do here, say N.
273 This feature enables support for PCI bus system. If you say Y
274 here, the kernel will include drivers and infrastructure code
275 to support PCI bus devices.
277 If you don't know what to do here, say Y.
282 config PCI_DOMAINS_GENERIC
285 source "drivers/pci/Kconfig"
289 menu "Power management options"
291 source kernel/power/Kconfig