xref: /linux/arch/riscv/Kconfig (revision 0774a6ed294b963dc76df2d8342ab86d030759ec)
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	select ARCH_CLOCKSOURCE_INIT
16	select ARCH_SUPPORTS_ATOMIC_RMW
17	select ARCH_HAS_BINFMT_FLAT
18	select ARCH_HAS_DEBUG_VM_PGTABLE
19	select ARCH_HAS_DEBUG_VIRTUAL if MMU
20	select ARCH_HAS_DEBUG_WX
21	select ARCH_HAS_GCOV_PROFILE_ALL
22	select ARCH_HAS_GIGANTIC_PAGE
23	select ARCH_HAS_KCOV
24	select ARCH_HAS_MMIOWB
25	select ARCH_HAS_PTE_SPECIAL
26	select ARCH_HAS_SET_DIRECT_MAP
27	select ARCH_HAS_SET_MEMORY
28	select ARCH_HAS_STRICT_KERNEL_RWX if MMU
29	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
30	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
31	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
32	select ARCH_WANT_FRAME_POINTERS
33	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
34	select CLONE_BACKWARDS
35	select CLINT_TIMER if !MMU
36	select COMMON_CLK
37	select EDAC_SUPPORT
38	select GENERIC_ARCH_TOPOLOGY if SMP
39	select GENERIC_ATOMIC64 if !64BIT
40	select GENERIC_EARLY_IOREMAP
41	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
42	select GENERIC_IOREMAP
43	select GENERIC_IRQ_MULTI_HANDLER
44	select GENERIC_IRQ_SHOW
45	select GENERIC_PCI_IOMAP
46	select GENERIC_PTDUMP if MMU
47	select GENERIC_SCHED_CLOCK
48	select GENERIC_SMP_IDLE_THREAD
49	select GENERIC_STRNCPY_FROM_USER if MMU
50	select GENERIC_STRNLEN_USER if MMU
51	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
52	select HANDLE_DOMAIN_IRQ
53	select HAVE_ARCH_AUDITSYSCALL
54	select HAVE_ARCH_JUMP_LABEL
55	select HAVE_ARCH_JUMP_LABEL_RELATIVE
56	select HAVE_ARCH_KASAN if MMU && 64BIT
57	select HAVE_ARCH_KGDB
58	select HAVE_ARCH_KGDB_QXFER_PKT
59	select HAVE_ARCH_MMAP_RND_BITS if MMU
60	select HAVE_ARCH_SECCOMP_FILTER
61	select HAVE_ARCH_TRACEHOOK
62	select HAVE_ASM_MODVERSIONS
63	select HAVE_CONTEXT_TRACKING
64	select HAVE_DEBUG_KMEMLEAK
65	select HAVE_DMA_CONTIGUOUS if MMU
66	select HAVE_EBPF_JIT if MMU
67	select HAVE_FUTEX_CMPXCHG if FUTEX
68	select HAVE_GCC_PLUGINS
69	select HAVE_GENERIC_VDSO if MMU && 64BIT
70	select HAVE_PCI
71	select HAVE_PERF_EVENTS
72	select HAVE_PERF_REGS
73	select HAVE_PERF_USER_STACK_DUMP
74	select HAVE_STACKPROTECTOR
75	select HAVE_SYSCALL_TRACEPOINTS
76	select IRQ_DOMAIN
77	select MODULES_USE_ELF_RELA if MODULES
78	select MODULE_SECTIONS if MODULES
79	select OF
80	select OF_EARLY_FLATTREE
81	select OF_IRQ
82	select PCI_DOMAINS_GENERIC if PCI
83	select PCI_MSI if PCI
84	select RISCV_INTC
85	select RISCV_TIMER if RISCV_SBI
86	select SPARSEMEM_STATIC if 32BIT
87	select SPARSE_IRQ
88	select SYSCTL_EXCEPTION_TRACE
89	select THREAD_INFO_IN_TASK
90	select UACCESS_MEMCPY if !MMU
91
92config ARCH_MMAP_RND_BITS_MIN
93	default 18 if 64BIT
94	default 8
95
96# max bits determined by the following formula:
97#  VA_BITS - PAGE_SHIFT - 3
98config ARCH_MMAP_RND_BITS_MAX
99	default 24 if 64BIT # SV39 based
100	default 17
101
102# set if we run in machine mode, cleared if we run in supervisor mode
103config RISCV_M_MODE
104	bool
105	default !MMU
106
107# set if we are running in S-mode and can use SBI calls
108config RISCV_SBI
109	bool
110	depends on !RISCV_M_MODE
111	default y
112
113config MMU
114	bool "MMU-based Paged Memory Management Support"
115	default y
116	help
117	  Select if you want MMU-based virtualised addressing space
118	  support by paged memory management. If unsure, say 'Y'.
119
120config ZONE_DMA32
121	bool
122	default y if 64BIT
123
124config VA_BITS
125	int
126	default 32 if 32BIT
127	default 39 if 64BIT
128
129config PA_BITS
130	int
131	default 34 if 32BIT
132	default 56 if 64BIT
133
134config PAGE_OFFSET
135	hex
136	default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
137	default 0x80000000 if 64BIT && !MMU
138	default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
139	default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
140
141config ARCH_FLATMEM_ENABLE
142	def_bool y
143
144config ARCH_SPARSEMEM_ENABLE
145	def_bool y
146	depends on MMU
147	select SPARSEMEM_VMEMMAP_ENABLE
148
149config ARCH_SELECT_MEMORY_MODEL
150	def_bool ARCH_SPARSEMEM_ENABLE
151
152config ARCH_WANT_GENERAL_HUGETLB
153	def_bool y
154
155config ARCH_SUPPORTS_DEBUG_PAGEALLOC
156	def_bool y
157
158config SYS_SUPPORTS_HUGETLBFS
159	depends on MMU
160	def_bool y
161
162config STACKTRACE_SUPPORT
163	def_bool y
164
165config TRACE_IRQFLAGS_SUPPORT
166	def_bool y
167
168config GENERIC_BUG
169	def_bool y
170	depends on BUG
171	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
172
173config GENERIC_BUG_RELATIVE_POINTERS
174	bool
175
176config GENERIC_CALIBRATE_DELAY
177	def_bool y
178
179config GENERIC_CSUM
180	def_bool y
181
182config GENERIC_HWEIGHT
183	def_bool y
184
185config FIX_EARLYCON_MEM
186	def_bool MMU
187
188config PGTABLE_LEVELS
189	int
190	default 3 if 64BIT
191	default 2
192
193config LOCKDEP_SUPPORT
194	def_bool y
195
196source "arch/riscv/Kconfig.socs"
197
198menu "Platform type"
199
200choice
201	prompt "Base ISA"
202	default ARCH_RV64I
203	help
204	  This selects the base ISA that this kernel will target and must match
205	  the target platform.
206
207config ARCH_RV32I
208	bool "RV32I"
209	select 32BIT
210	select GENERIC_LIB_ASHLDI3
211	select GENERIC_LIB_ASHRDI3
212	select GENERIC_LIB_LSHRDI3
213	select GENERIC_LIB_UCMPDI2
214	select MMU
215
216config ARCH_RV64I
217	bool "RV64I"
218	select 64BIT
219	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
220	select HAVE_DYNAMIC_FTRACE if MMU
221	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
222	select HAVE_FTRACE_MCOUNT_RECORD
223	select HAVE_FUNCTION_GRAPH_TRACER
224	select HAVE_FUNCTION_TRACER
225	select SWIOTLB if MMU
226
227endchoice
228
229# We must be able to map all physical memory into the kernel, but the compiler
230# is still a bit more efficient when generating code if it's setup in a manner
231# such that it can only map 2GiB of memory.
232choice
233	prompt "Kernel Code Model"
234	default CMODEL_MEDLOW if 32BIT
235	default CMODEL_MEDANY if 64BIT
236
237	config CMODEL_MEDLOW
238		bool "medium low code model"
239	config CMODEL_MEDANY
240		bool "medium any code model"
241endchoice
242
243config MODULE_SECTIONS
244	bool
245	select HAVE_MOD_ARCH_SPECIFIC
246
247choice
248	prompt "Maximum Physical Memory"
249	default MAXPHYSMEM_2GB if 32BIT
250	default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
251	default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
252
253	config MAXPHYSMEM_2GB
254		bool "2GiB"
255	config MAXPHYSMEM_128GB
256		depends on 64BIT && CMODEL_MEDANY
257		bool "128GiB"
258endchoice
259
260
261config SMP
262	bool "Symmetric Multi-Processing"
263	help
264	  This enables support for systems with more than one CPU.  If
265	  you say N here, the kernel will run on single and
266	  multiprocessor machines, but will use only one CPU of a
267	  multiprocessor machine. If you say Y here, the kernel will run
268	  on many, but not all, single processor machines. On a single
269	  processor machine, the kernel will run faster if you say N
270	  here.
271
272	  If you don't know what to do here, say N.
273
274config NR_CPUS
275	int "Maximum number of CPUs (2-32)"
276	range 2 32
277	depends on SMP
278	default "8"
279
280config HOTPLUG_CPU
281	bool "Support for hot-pluggable CPUs"
282	depends on SMP
283	select GENERIC_IRQ_MIGRATION
284	help
285
286	  Say Y here to experiment with turning CPUs off and on.  CPUs
287	  can be controlled through /sys/devices/system/cpu.
288
289	  Say N if you want to disable CPU hotplug.
290
291choice
292	prompt "CPU Tuning"
293	default TUNE_GENERIC
294
295config TUNE_GENERIC
296	bool "generic"
297
298endchoice
299
300config RISCV_ISA_C
301	bool "Emit compressed instructions when building Linux"
302	default y
303	help
304	   Adds "C" to the ISA subsets that the toolchain is allowed to emit
305	   when building Linux, which results in compressed instructions in the
306	   Linux binary.
307
308	   If you don't know what to do here, say Y.
309
310menu "supported PMU type"
311	depends on PERF_EVENTS
312
313config RISCV_BASE_PMU
314	bool "Base Performance Monitoring Unit"
315	def_bool y
316	help
317	  A base PMU that serves as a reference implementation and has limited
318	  feature of perf.  It can run on any RISC-V machines so serves as the
319	  fallback, but this option can also be disable to reduce kernel size.
320
321endmenu
322
323config FPU
324	bool "FPU support"
325	default y
326	help
327	  Say N here if you want to disable all floating-point related procedure
328	  in the kernel.
329
330	  If you don't know what to do here, say Y.
331
332endmenu
333
334menu "Kernel features"
335
336source "kernel/Kconfig.hz"
337
338config RISCV_SBI_V01
339	bool "SBI v0.1 support"
340	default y
341	depends on RISCV_SBI
342	help
343	  This config allows kernel to use SBI v0.1 APIs. This will be
344	  deprecated in future once legacy M-mode software are no longer in use.
345endmenu
346
347menu "Boot options"
348
349config CMDLINE
350	string "Built-in kernel command line"
351	help
352	  For most platforms, the arguments for the kernel's command line
353	  are provided at run-time, during boot. However, there are cases
354	  where either no arguments are being provided or the provided
355	  arguments are insufficient or even invalid.
356
357	  When that occurs, it is possible to define a built-in command
358	  line here and choose how the kernel should use it later on.
359
360choice
361	prompt "Built-in command line usage" if CMDLINE != ""
362	default CMDLINE_FALLBACK
363	help
364	  Choose how the kernel will handle the provided built-in command
365	  line.
366
367config CMDLINE_FALLBACK
368	bool "Use bootloader kernel arguments if available"
369	help
370	  Use the built-in command line as fallback in case we get nothing
371	  during boot. This is the default behaviour.
372
373config CMDLINE_EXTEND
374	bool "Extend bootloader kernel arguments"
375	help
376	  The command-line arguments provided during boot will be
377	  appended to the built-in command line. This is useful in
378	  cases where the provided arguments are insufficient and
379	  you don't want to or cannot modify them.
380
381
382config CMDLINE_FORCE
383	bool "Always use the default kernel command string"
384	help
385	  Always use the built-in command line, even if we get one during
386	  boot. This is useful in case you need to override the provided
387	  command line on systems where you don't have or want control
388	  over it.
389
390endchoice
391
392config EFI_STUB
393	bool
394
395config EFI
396	bool "UEFI runtime support"
397	depends on OF
398	select LIBFDT
399	select UCS2_STRING
400	select EFI_PARAMS_FROM_FDT
401	select EFI_STUB
402	select EFI_GENERIC_STUB
403	select EFI_RUNTIME_WRAPPERS
404	select RISCV_ISA_C
405	depends on MMU
406	default y
407	help
408	  This option provides support for runtime services provided
409	  by UEFI firmware (such as non-volatile variables, realtime
410	  clock, and platform reset). A UEFI stub is also provided to
411	  allow the kernel to be booted as an EFI application. This
412	  is only useful on systems that have UEFI firmware.
413
414endmenu
415
416config BUILTIN_DTB
417	def_bool n
418	depends on RISCV_M_MODE
419	depends on OF
420
421menu "Power management options"
422
423source "kernel/power/Kconfig"
424
425endmenu
426
427source "drivers/firmware/Kconfig"
428