xref: /linux/arch/riscv/Kconfig (revision fba8a8674f68a0628abae470dfcfbcb4a0d7a79e)
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_SUPPORTS_DEBUG_PAGEALLOC if MMU
18	select ARCH_STACKWALK
19	select ARCH_HAS_BINFMT_FLAT
20	select ARCH_HAS_DEBUG_VM_PGTABLE
21	select ARCH_HAS_DEBUG_VIRTUAL if MMU
22	select ARCH_HAS_DEBUG_WX
23	select ARCH_HAS_FORTIFY_SOURCE
24	select ARCH_HAS_GCOV_PROFILE_ALL
25	select ARCH_HAS_GIGANTIC_PAGE
26	select ARCH_HAS_KCOV
27	select ARCH_HAS_MMIOWB
28	select ARCH_HAS_PTE_SPECIAL
29	select ARCH_HAS_SET_DIRECT_MAP
30	select ARCH_HAS_SET_MEMORY
31	select ARCH_HAS_STRICT_KERNEL_RWX if MMU
32	select ARCH_HAS_STRICT_MODULE_RWX if MMU
33	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
34	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
35	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
36	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
37	select ARCH_WANT_FRAME_POINTERS
38	select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
39	select CLONE_BACKWARDS
40	select CLINT_TIMER if !MMU
41	select COMMON_CLK
42	select EDAC_SUPPORT
43	select GENERIC_ARCH_TOPOLOGY if SMP
44	select GENERIC_ATOMIC64 if !64BIT
45	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
46	select GENERIC_EARLY_IOREMAP
47	select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
48	select GENERIC_IOREMAP
49	select GENERIC_IRQ_MULTI_HANDLER
50	select GENERIC_IRQ_SHOW
51	select GENERIC_LIB_DEVMEM_IS_ALLOWED
52	select GENERIC_PCI_IOMAP
53	select GENERIC_PTDUMP if MMU
54	select GENERIC_SCHED_CLOCK
55	select GENERIC_SMP_IDLE_THREAD
56	select GENERIC_STRNCPY_FROM_USER if MMU
57	select GENERIC_STRNLEN_USER if MMU
58	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
59	select HANDLE_DOMAIN_IRQ
60	select HAVE_ARCH_AUDITSYSCALL
61	select HAVE_ARCH_JUMP_LABEL
62	select HAVE_ARCH_JUMP_LABEL_RELATIVE
63	select HAVE_ARCH_KASAN if MMU && 64BIT
64	select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
65	select HAVE_ARCH_KGDB
66	select HAVE_ARCH_KGDB_QXFER_PKT
67	select HAVE_ARCH_MMAP_RND_BITS if MMU
68	select HAVE_ARCH_SECCOMP_FILTER
69	select HAVE_ARCH_TRACEHOOK
70	select HAVE_ASM_MODVERSIONS
71	select HAVE_CONTEXT_TRACKING
72	select HAVE_DEBUG_KMEMLEAK
73	select HAVE_DMA_CONTIGUOUS if MMU
74	select HAVE_EBPF_JIT if MMU
75	select HAVE_FUNCTION_ERROR_INJECTION
76	select HAVE_FUTEX_CMPXCHG if FUTEX
77	select HAVE_GCC_PLUGINS
78	select HAVE_GENERIC_VDSO if MMU && 64BIT
79	select HAVE_IRQ_TIME_ACCOUNTING
80	select HAVE_KPROBES
81	select HAVE_KPROBES_ON_FTRACE
82	select HAVE_KRETPROBES
83	select HAVE_PCI
84	select HAVE_PERF_EVENTS
85	select HAVE_PERF_REGS
86	select HAVE_PERF_USER_STACK_DUMP
87	select HAVE_REGS_AND_STACK_ACCESS_API
88	select HAVE_STACKPROTECTOR
89	select HAVE_SYSCALL_TRACEPOINTS
90	select IRQ_DOMAIN
91	select MODULES_USE_ELF_RELA if MODULES
92	select MODULE_SECTIONS if MODULES
93	select OF
94	select OF_EARLY_FLATTREE
95	select OF_IRQ
96	select PCI_DOMAINS_GENERIC if PCI
97	select PCI_MSI if PCI
98	select RISCV_INTC
99	select RISCV_TIMER if RISCV_SBI
100	select SPARSEMEM_STATIC if 32BIT
101	select SPARSE_IRQ
102	select SYSCTL_EXCEPTION_TRACE
103	select THREAD_INFO_IN_TASK
104	select UACCESS_MEMCPY if !MMU
105
106config ARCH_MMAP_RND_BITS_MIN
107	default 18 if 64BIT
108	default 8
109
110# max bits determined by the following formula:
111#  VA_BITS - PAGE_SHIFT - 3
112config ARCH_MMAP_RND_BITS_MAX
113	default 24 if 64BIT # SV39 based
114	default 17
115
116# set if we run in machine mode, cleared if we run in supervisor mode
117config RISCV_M_MODE
118	bool
119	default !MMU
120
121# set if we are running in S-mode and can use SBI calls
122config RISCV_SBI
123	bool
124	depends on !RISCV_M_MODE
125	default y
126
127config MMU
128	bool "MMU-based Paged Memory Management Support"
129	default y
130	help
131	  Select if you want MMU-based virtualised addressing space
132	  support by paged memory management. If unsure, say 'Y'.
133
134config ZONE_DMA32
135	bool
136	default y if 64BIT
137
138config VA_BITS
139	int
140	default 32 if 32BIT
141	default 39 if 64BIT
142
143config PA_BITS
144	int
145	default 34 if 32BIT
146	default 56 if 64BIT
147
148config PAGE_OFFSET
149	hex
150	default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
151	default 0x80000000 if 64BIT && !MMU
152	default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
153	default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
154
155config ARCH_FLATMEM_ENABLE
156	def_bool !NUMA
157
158config ARCH_SPARSEMEM_ENABLE
159	def_bool y
160	depends on MMU
161	select SPARSEMEM_VMEMMAP_ENABLE
162
163config ARCH_SELECT_MEMORY_MODEL
164	def_bool ARCH_SPARSEMEM_ENABLE
165
166config ARCH_WANT_GENERAL_HUGETLB
167	def_bool y
168
169config ARCH_SUPPORTS_UPROBES
170	def_bool y
171
172config SYS_SUPPORTS_HUGETLBFS
173	depends on MMU
174	def_bool y
175
176config STACKTRACE_SUPPORT
177	def_bool y
178
179config TRACE_IRQFLAGS_SUPPORT
180	def_bool y
181
182config GENERIC_BUG
183	def_bool y
184	depends on BUG
185	select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
186
187config GENERIC_BUG_RELATIVE_POINTERS
188	bool
189
190config GENERIC_CALIBRATE_DELAY
191	def_bool y
192
193config GENERIC_CSUM
194	def_bool y
195
196config GENERIC_HWEIGHT
197	def_bool y
198
199config FIX_EARLYCON_MEM
200	def_bool MMU
201
202config PGTABLE_LEVELS
203	int
204	default 3 if 64BIT
205	default 2
206
207config LOCKDEP_SUPPORT
208	def_bool y
209
210source "arch/riscv/Kconfig.socs"
211source "arch/riscv/Kconfig.erratas"
212
213menu "Platform type"
214
215choice
216	prompt "Base ISA"
217	default ARCH_RV64I
218	help
219	  This selects the base ISA that this kernel will target and must match
220	  the target platform.
221
222config ARCH_RV32I
223	bool "RV32I"
224	select 32BIT
225	select GENERIC_LIB_ASHLDI3
226	select GENERIC_LIB_ASHRDI3
227	select GENERIC_LIB_LSHRDI3
228	select GENERIC_LIB_UCMPDI2
229	select MMU
230
231config ARCH_RV64I
232	bool "RV64I"
233	select 64BIT
234	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
235	select HAVE_DYNAMIC_FTRACE if MMU && $(cc-option,-fpatchable-function-entry=8)
236	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
237	select HAVE_FTRACE_MCOUNT_RECORD
238	select HAVE_FUNCTION_GRAPH_TRACER
239	select HAVE_FUNCTION_TRACER
240	select SWIOTLB if MMU
241
242endchoice
243
244# We must be able to map all physical memory into the kernel, but the compiler
245# is still a bit more efficient when generating code if it's setup in a manner
246# such that it can only map 2GiB of memory.
247choice
248	prompt "Kernel Code Model"
249	default CMODEL_MEDLOW if 32BIT
250	default CMODEL_MEDANY if 64BIT
251
252	config CMODEL_MEDLOW
253		bool "medium low code model"
254	config CMODEL_MEDANY
255		bool "medium any code model"
256endchoice
257
258config MODULE_SECTIONS
259	bool
260	select HAVE_MOD_ARCH_SPECIFIC
261
262choice
263	prompt "Maximum Physical Memory"
264	default MAXPHYSMEM_1GB if 32BIT
265	default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
266	default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
267
268	config MAXPHYSMEM_1GB
269		depends on 32BIT
270		bool "1GiB"
271	config MAXPHYSMEM_2GB
272		depends on 64BIT && CMODEL_MEDLOW
273		bool "2GiB"
274	config MAXPHYSMEM_128GB
275		depends on 64BIT && CMODEL_MEDANY
276		bool "128GiB"
277endchoice
278
279
280config SMP
281	bool "Symmetric Multi-Processing"
282	help
283	  This enables support for systems with more than one CPU.  If
284	  you say N here, the kernel will run on single and
285	  multiprocessor machines, but will use only one CPU of a
286	  multiprocessor machine. If you say Y here, the kernel will run
287	  on many, but not all, single processor machines. On a single
288	  processor machine, the kernel will run faster if you say N
289	  here.
290
291	  If you don't know what to do here, say N.
292
293config NR_CPUS
294	int "Maximum number of CPUs (2-32)"
295	range 2 32
296	depends on SMP
297	default "8"
298
299config HOTPLUG_CPU
300	bool "Support for hot-pluggable CPUs"
301	depends on SMP
302	select GENERIC_IRQ_MIGRATION
303	help
304
305	  Say Y here to experiment with turning CPUs off and on.  CPUs
306	  can be controlled through /sys/devices/system/cpu.
307
308	  Say N if you want to disable CPU hotplug.
309
310choice
311	prompt "CPU Tuning"
312	default TUNE_GENERIC
313
314config TUNE_GENERIC
315	bool "generic"
316
317endchoice
318
319# Common NUMA Features
320config NUMA
321	bool "NUMA Memory Allocation and Scheduler Support"
322	depends on SMP
323	select GENERIC_ARCH_NUMA
324	select OF_NUMA
325	select ARCH_SUPPORTS_NUMA_BALANCING
326	help
327	  Enable NUMA (Non-Uniform Memory Access) support.
328
329	  The kernel will try to allocate memory used by a CPU on the
330	  local memory of the CPU and add some more NUMA awareness to the kernel.
331
332config NODES_SHIFT
333	int "Maximum NUMA Nodes (as a power of 2)"
334	range 1 10
335	default "2"
336	depends on NEED_MULTIPLE_NODES
337	help
338	  Specify the maximum number of NUMA Nodes available on the target
339	  system.  Increases memory reserved to accommodate various tables.
340
341config USE_PERCPU_NUMA_NODE_ID
342	def_bool y
343	depends on NUMA
344
345config NEED_PER_CPU_EMBED_FIRST_CHUNK
346	def_bool y
347	depends on NUMA
348
349config RISCV_ISA_C
350	bool "Emit compressed instructions when building Linux"
351	default y
352	help
353	   Adds "C" to the ISA subsets that the toolchain is allowed to emit
354	   when building Linux, which results in compressed instructions in the
355	   Linux binary.
356
357	   If you don't know what to do here, say Y.
358
359menu "supported PMU type"
360	depends on PERF_EVENTS
361
362config RISCV_BASE_PMU
363	bool "Base Performance Monitoring Unit"
364	def_bool y
365	help
366	  A base PMU that serves as a reference implementation and has limited
367	  feature of perf.  It can run on any RISC-V machines so serves as the
368	  fallback, but this option can also be disable to reduce kernel size.
369
370endmenu
371
372config FPU
373	bool "FPU support"
374	default y
375	help
376	  Say N here if you want to disable all floating-point related procedure
377	  in the kernel.
378
379	  If you don't know what to do here, say Y.
380
381endmenu
382
383menu "Kernel features"
384
385source "kernel/Kconfig.hz"
386
387config RISCV_SBI_V01
388	bool "SBI v0.1 support"
389	default y
390	depends on RISCV_SBI
391	help
392	  This config allows kernel to use SBI v0.1 APIs. This will be
393	  deprecated in future once legacy M-mode software are no longer in use.
394
395config KEXEC
396	bool "Kexec system call"
397	select KEXEC_CORE
398	select HOTPLUG_CPU if SMP
399	depends on MMU
400	help
401	  kexec is a system call that implements the ability to shutdown your
402	  current kernel, and to start another kernel. It is like a reboot
403	  but it is independent of the system firmware. And like a reboot
404	  you can start any kernel with it, not just Linux.
405
406	  The name comes from the similarity to the exec system call.
407
408
409endmenu
410
411menu "Boot options"
412
413config CMDLINE
414	string "Built-in kernel command line"
415	help
416	  For most platforms, the arguments for the kernel's command line
417	  are provided at run-time, during boot. However, there are cases
418	  where either no arguments are being provided or the provided
419	  arguments are insufficient or even invalid.
420
421	  When that occurs, it is possible to define a built-in command
422	  line here and choose how the kernel should use it later on.
423
424choice
425	prompt "Built-in command line usage" if CMDLINE != ""
426	default CMDLINE_FALLBACK
427	help
428	  Choose how the kernel will handle the provided built-in command
429	  line.
430
431config CMDLINE_FALLBACK
432	bool "Use bootloader kernel arguments if available"
433	help
434	  Use the built-in command line as fallback in case we get nothing
435	  during boot. This is the default behaviour.
436
437config CMDLINE_EXTEND
438	bool "Extend bootloader kernel arguments"
439	help
440	  The command-line arguments provided during boot will be
441	  appended to the built-in command line. This is useful in
442	  cases where the provided arguments are insufficient and
443	  you don't want to or cannot modify them.
444
445
446config CMDLINE_FORCE
447	bool "Always use the default kernel command string"
448	help
449	  Always use the built-in command line, even if we get one during
450	  boot. This is useful in case you need to override the provided
451	  command line on systems where you don't have or want control
452	  over it.
453
454endchoice
455
456config EFI_STUB
457	bool
458
459config EFI
460	bool "UEFI runtime support"
461	depends on OF
462	select LIBFDT
463	select UCS2_STRING
464	select EFI_PARAMS_FROM_FDT
465	select EFI_STUB
466	select EFI_GENERIC_STUB
467	select EFI_RUNTIME_WRAPPERS
468	select RISCV_ISA_C
469	depends on MMU
470	default y
471	help
472	  This option provides support for runtime services provided
473	  by UEFI firmware (such as non-volatile variables, realtime
474	  clock, and platform reset). A UEFI stub is also provided to
475	  allow the kernel to be booted as an EFI application. This
476	  is only useful on systems that have UEFI firmware.
477
478config CC_HAVE_STACKPROTECTOR_TLS
479	def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
480
481config STACKPROTECTOR_PER_TASK
482	def_bool y
483	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
484
485endmenu
486
487config BUILTIN_DTB
488	def_bool n
489	depends on OF
490
491menu "Power management options"
492
493source "kernel/power/Kconfig"
494
495endmenu
496
497source "drivers/firmware/Kconfig"
498