1
2
3
4
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_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
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_FORTIFY_SOURCE
22 select ARCH_HAS_GCOV_PROFILE_ALL
23 select ARCH_HAS_GIGANTIC_PAGE
24 select ARCH_HAS_KCOV
25 select ARCH_HAS_MMIOWB
26 select ARCH_HAS_PTE_SPECIAL
27 select ARCH_HAS_SET_DIRECT_MAP if MMU
28 select ARCH_HAS_SET_MEMORY if MMU
29 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
30 select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
31 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
32 select ARCH_HAS_UBSAN_SANITIZE_ALL
33 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
34 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
35 select ARCH_STACKWALK
36 select ARCH_SUPPORTS_ATOMIC_RMW
37 select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
38 select ARCH_SUPPORTS_HUGETLBFS if MMU
39 select ARCH_USE_MEMTEST
40 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
41 select ARCH_WANT_FRAME_POINTERS
42 select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
43 select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU
44 select BUILDTIME_TABLE_SORT if MMU
45 select CLONE_BACKWARDS
46 select CLINT_TIMER if !MMU
47 select COMMON_CLK
48 select EDAC_SUPPORT
49 select GENERIC_ARCH_TOPOLOGY if SMP
50 select GENERIC_ATOMIC64 if !64BIT
51 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
52 select GENERIC_EARLY_IOREMAP
53 select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
54 select GENERIC_IDLE_POLL_SETUP
55 select GENERIC_IOREMAP if MMU
56 select GENERIC_IRQ_MULTI_HANDLER
57 select GENERIC_IRQ_SHOW
58 select GENERIC_IRQ_SHOW_LEVEL
59 select GENERIC_LIB_DEVMEM_IS_ALLOWED
60 select GENERIC_PCI_IOMAP
61 select GENERIC_PTDUMP if MMU
62 select GENERIC_SCHED_CLOCK
63 select GENERIC_SMP_IDLE_THREAD
64 select GENERIC_TIME_VSYSCALL if MMU && 64BIT
65 select HANDLE_DOMAIN_IRQ
66 select HAVE_ARCH_AUDITSYSCALL
67 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
68 select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
69 select HAVE_ARCH_KASAN if MMU && 64BIT
70 select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT
71 select HAVE_ARCH_KFENCE if MMU && 64BIT
72 select HAVE_ARCH_KGDB if !XIP_KERNEL
73 select HAVE_ARCH_KGDB_QXFER_PKT
74 select HAVE_ARCH_MMAP_RND_BITS if MMU
75 select HAVE_ARCH_SECCOMP_FILTER
76 select HAVE_ARCH_TRACEHOOK
77 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT && MMU
78 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
79 select HAVE_ARCH_VMAP_STACK if MMU && 64BIT
80 select HAVE_ASM_MODVERSIONS
81 select HAVE_CONTEXT_TRACKING
82 select HAVE_DEBUG_KMEMLEAK
83 select HAVE_DMA_CONTIGUOUS if MMU
84 select HAVE_EBPF_JIT if MMU
85 select HAVE_FUNCTION_ERROR_INJECTION
86 select HAVE_FUTEX_CMPXCHG if FUTEX
87 select HAVE_GCC_PLUGINS
88 select HAVE_GENERIC_VDSO if MMU && 64BIT
89 select HAVE_IRQ_TIME_ACCOUNTING
90 select HAVE_KPROBES if !XIP_KERNEL
91 select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL
92 select HAVE_KRETPROBES if !XIP_KERNEL
93 select HAVE_MOVE_PMD
94 select HAVE_MOVE_PUD
95 select HAVE_PCI
96 select HAVE_PERF_EVENTS
97 select HAVE_PERF_REGS
98 select HAVE_PERF_USER_STACK_DUMP
99 select HAVE_REGS_AND_STACK_ACCESS_API
100 select HAVE_FUNCTION_ARG_ACCESS_API
101 select HAVE_STACKPROTECTOR
102 select HAVE_SYSCALL_TRACEPOINTS
103 select IRQ_DOMAIN
104 select IRQ_FORCED_THREADING
105 select MODULES_USE_ELF_RELA if MODULES
106 select MODULE_SECTIONS if MODULES
107 select OF
108 select OF_EARLY_FLATTREE
109 select OF_IRQ
110 select PCI_DOMAINS_GENERIC if PCI
111 select PCI_MSI if PCI
112 select RISCV_INTC
113 select RISCV_TIMER if RISCV_SBI
114 select SPARSE_IRQ
115 select SYSCTL_EXCEPTION_TRACE
116 select THREAD_INFO_IN_TASK
117 select TRACE_IRQFLAGS_SUPPORT
118 select UACCESS_MEMCPY if !MMU
119 select ZONE_DMA32 if 64BIT
120
121config ARCH_MMAP_RND_BITS_MIN
122 default 18 if 64BIT
123 default 8
124
125
126
127config ARCH_MMAP_RND_BITS_MAX
128 default 24 if 64BIT
129 default 17
130
131
132config RISCV_M_MODE
133 bool
134 default !MMU
135
136
137config RISCV_SBI
138 bool
139 depends on !RISCV_M_MODE
140 default y
141
142config MMU
143 bool "MMU-based Paged Memory Management Support"
144 default y
145 help
146 Select if you want MMU-based virtualised addressing space
147 support by paged memory management. If unsure, say 'Y'.
148
149config VA_BITS
150 int
151 default 32 if 32BIT
152 default 39 if 64BIT
153
154config PA_BITS
155 int
156 default 34 if 32BIT
157 default 56 if 64BIT
158
159config PAGE_OFFSET
160 hex
161 default 0xC0000000 if 32BIT && MAXPHYSMEM_1GB
162 default 0x80000000 if 64BIT && !MMU
163 default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
164 default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
165
166config KASAN_SHADOW_OFFSET
167 hex
168 depends on KASAN_GENERIC
169 default 0xdfffffc800000000 if 64BIT
170 default 0xffffffff if 32BIT
171
172config ARCH_FLATMEM_ENABLE
173 def_bool !NUMA
174
175config ARCH_SPARSEMEM_ENABLE
176 def_bool y
177 depends on MMU
178 select SPARSEMEM_STATIC if 32BIT && SPARSEMEM
179 select SPARSEMEM_VMEMMAP_ENABLE if 64BIT
180
181config ARCH_SELECT_MEMORY_MODEL
182 def_bool ARCH_SPARSEMEM_ENABLE
183
184config ARCH_WANT_GENERAL_HUGETLB
185 def_bool y
186
187config ARCH_SUPPORTS_UPROBES
188 def_bool y
189
190config STACKTRACE_SUPPORT
191 def_bool y
192
193config GENERIC_BUG
194 def_bool y
195 depends on BUG
196 select GENERIC_BUG_RELATIVE_POINTERS if 64BIT
197
198config GENERIC_BUG_RELATIVE_POINTERS
199 bool
200
201config GENERIC_CALIBRATE_DELAY
202 def_bool y
203
204config GENERIC_CSUM
205 def_bool y
206
207config GENERIC_HWEIGHT
208 def_bool y
209
210config FIX_EARLYCON_MEM
211 def_bool MMU
212
213config PGTABLE_LEVELS
214 int
215 default 3 if 64BIT
216 default 2
217
218config LOCKDEP_SUPPORT
219 def_bool y
220
221source "arch/riscv/Kconfig.socs"
222source "arch/riscv/Kconfig.erratas"
223
224menu "Platform type"
225
226choice
227 prompt "Base ISA"
228 default ARCH_RV64I
229 help
230 This selects the base ISA that this kernel will target and must match
231 the target platform.
232
233config ARCH_RV32I
234 bool "RV32I"
235 select 32BIT
236 select GENERIC_LIB_ASHLDI3
237 select GENERIC_LIB_ASHRDI3
238 select GENERIC_LIB_LSHRDI3
239 select GENERIC_LIB_UCMPDI2
240 select MMU
241
242config ARCH_RV64I
243 bool "RV64I"
244 select 64BIT
245 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
246 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
247 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
248 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
249 select HAVE_FUNCTION_GRAPH_TRACER
250 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
251 select SWIOTLB if MMU
252
253endchoice
254
255
256
257
258choice
259 prompt "Kernel Code Model"
260 default CMODEL_MEDLOW if 32BIT
261 default CMODEL_MEDANY if 64BIT
262
263 config CMODEL_MEDLOW
264 bool "medium low code model"
265 config CMODEL_MEDANY
266 bool "medium any code model"
267endchoice
268
269config MODULE_SECTIONS
270 bool
271 select HAVE_MOD_ARCH_SPECIFIC
272
273choice
274 prompt "Maximum Physical Memory"
275 default MAXPHYSMEM_1GB if 32BIT
276 default MAXPHYSMEM_2GB if 64BIT && CMODEL_MEDLOW
277 default MAXPHYSMEM_128GB if 64BIT && CMODEL_MEDANY
278
279 config MAXPHYSMEM_1GB
280 depends on 32BIT
281 bool "1GiB"
282 config MAXPHYSMEM_2GB
283 depends on 64BIT && CMODEL_MEDLOW
284 bool "2GiB"
285 config MAXPHYSMEM_128GB
286 depends on 64BIT && CMODEL_MEDANY
287 bool "128GiB"
288endchoice
289
290
291config SMP
292 bool "Symmetric Multi-Processing"
293 help
294 This enables support for systems with more than one CPU. If
295 you say N here, the kernel will run on single and
296 multiprocessor machines, but will use only one CPU of a
297 multiprocessor machine. If you say Y here, the kernel will run
298 on many, but not all, single processor machines. On a single
299 processor machine, the kernel will run faster if you say N
300 here.
301
302 If you don't know what to do here, say N.
303
304config NR_CPUS
305 int "Maximum number of CPUs (2-32)"
306 range 2 32
307 depends on SMP
308 default "8"
309
310config HOTPLUG_CPU
311 bool "Support for hot-pluggable CPUs"
312 depends on SMP
313 select GENERIC_IRQ_MIGRATION
314 help
315
316 Say Y here to experiment with turning CPUs off and on. CPUs
317 can be controlled through /sys/devices/system/cpu.
318
319 Say N if you want to disable CPU hotplug.
320
321choice
322 prompt "CPU Tuning"
323 default TUNE_GENERIC
324
325config TUNE_GENERIC
326 bool "generic"
327
328endchoice
329
330
331config NUMA
332 bool "NUMA Memory Allocation and Scheduler Support"
333 depends on SMP && MMU
334 select GENERIC_ARCH_NUMA
335 select OF_NUMA
336 select ARCH_SUPPORTS_NUMA_BALANCING
337 help
338 Enable NUMA (Non-Uniform Memory Access) support.
339
340 The kernel will try to allocate memory used by a CPU on the
341 local memory of the CPU and add some more NUMA awareness to the kernel.
342
343config NODES_SHIFT
344 int "Maximum NUMA Nodes (as a power of 2)"
345 range 1 10
346 default "2"
347 depends on NUMA
348 help
349 Specify the maximum number of NUMA Nodes available on the target
350 system. Increases memory reserved to accommodate various tables.
351
352config USE_PERCPU_NUMA_NODE_ID
353 def_bool y
354 depends on NUMA
355
356config NEED_PER_CPU_EMBED_FIRST_CHUNK
357 def_bool y
358 depends on NUMA
359
360config RISCV_ISA_C
361 bool "Emit compressed instructions when building Linux"
362 default y
363 help
364 Adds "C" to the ISA subsets that the toolchain is allowed to emit
365 when building Linux, which results in compressed instructions in the
366 Linux binary.
367
368 If you don't know what to do here, say Y.
369
370menu "supported PMU type"
371 depends on PERF_EVENTS
372
373config RISCV_BASE_PMU
374 bool "Base Performance Monitoring Unit"
375 def_bool y
376 help
377 A base PMU that serves as a reference implementation and has limited
378 feature of perf. It can run on any RISC-V machines so serves as the
379 fallback, but this option can also be disable to reduce kernel size.
380
381endmenu
382
383config FPU
384 bool "FPU support"
385 default y
386 help
387 Say N here if you want to disable all floating-point related procedure
388 in the kernel.
389
390 If you don't know what to do here, say Y.
391
392endmenu
393
394menu "Kernel features"
395
396source "kernel/Kconfig.hz"
397
398config RISCV_SBI_V01
399 bool "SBI v0.1 support"
400 default y
401 depends on RISCV_SBI
402 help
403 This config allows kernel to use SBI v0.1 APIs. This will be
404 deprecated in future once legacy M-mode software are no longer in use.
405
406config KEXEC
407 bool "Kexec system call"
408 select KEXEC_CORE
409 select HOTPLUG_CPU if SMP
410 depends on MMU
411 help
412 kexec is a system call that implements the ability to shutdown your
413 current kernel, and to start another kernel. It is like a reboot
414 but it is independent of the system firmware. And like a reboot
415 you can start any kernel with it, not just Linux.
416
417 The name comes from the similarity to the exec system call.
418
419config CRASH_DUMP
420 bool "Build kdump crash kernel"
421 help
422 Generate crash dump after being started by kexec. This should
423 be normally only set in special crash dump kernels which are
424 loaded in the main kernel with kexec-tools into a specially
425 reserved region and then later executed after a crash by
426 kdump/kexec.
427
428 For more details see Documentation/admin-guide/kdump/kdump.rst
429
430endmenu
431
432menu "Boot options"
433
434config CMDLINE
435 string "Built-in kernel command line"
436 help
437 For most platforms, the arguments for the kernel's command line
438 are provided at run-time, during boot. However, there are cases
439 where either no arguments are being provided or the provided
440 arguments are insufficient or even invalid.
441
442 When that occurs, it is possible to define a built-in command
443 line here and choose how the kernel should use it later on.
444
445choice
446 prompt "Built-in command line usage" if CMDLINE != ""
447 default CMDLINE_FALLBACK
448 help
449 Choose how the kernel will handle the provided built-in command
450 line.
451
452config CMDLINE_FALLBACK
453 bool "Use bootloader kernel arguments if available"
454 help
455 Use the built-in command line as fallback in case we get nothing
456 during boot. This is the default behaviour.
457
458config CMDLINE_EXTEND
459 bool "Extend bootloader kernel arguments"
460 help
461 The command-line arguments provided during boot will be
462 appended to the built-in command line. This is useful in
463 cases where the provided arguments are insufficient and
464 you don't want to or cannot modify them.
465
466
467config CMDLINE_FORCE
468 bool "Always use the default kernel command string"
469 help
470 Always use the built-in command line, even if we get one during
471 boot. This is useful in case you need to override the provided
472 command line on systems where you don't have or want control
473 over it.
474
475endchoice
476
477config EFI_STUB
478 bool
479
480config EFI
481 bool "UEFI runtime support"
482 depends on OF && !XIP_KERNEL
483 select LIBFDT
484 select UCS2_STRING
485 select EFI_PARAMS_FROM_FDT
486 select EFI_STUB
487 select EFI_GENERIC_STUB
488 select EFI_RUNTIME_WRAPPERS
489 select RISCV_ISA_C
490 depends on MMU
491 default y
492 help
493 This option provides support for runtime services provided
494 by UEFI firmware (such as non-volatile variables, realtime
495 clock, and platform reset). A UEFI stub is also provided to
496 allow the kernel to be booted as an EFI application. This
497 is only useful on systems that have UEFI firmware.
498
499config CC_HAVE_STACKPROTECTOR_TLS
500 def_bool $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=tp -mstack-protector-guard-offset=0)
501
502config STACKPROTECTOR_PER_TASK
503 def_bool y
504 depends on !GCC_PLUGIN_RANDSTRUCT
505 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS
506
507config PHYS_RAM_BASE_FIXED
508 bool "Explicitly specified physical RAM address"
509 default n
510
511config PHYS_RAM_BASE
512 hex "Platform Physical RAM address"
513 depends on PHYS_RAM_BASE_FIXED
514 default "0x80000000"
515 help
516 This is the physical address of RAM in the system. It has to be
517 explicitly specified to run early relocations of read-write data
518 from flash to RAM.
519
520config XIP_KERNEL
521 bool "Kernel Execute-In-Place from ROM"
522 depends on MMU && SPARSEMEM
523
524
525 depends on !COMPILE_TEST
526 select PHYS_RAM_BASE_FIXED
527 help
528 Execute-In-Place allows the kernel to run from non-volatile storage
529 directly addressable by the CPU, such as NOR flash. This saves RAM
530 space since the text section of the kernel is not loaded from flash
531 to RAM. Read-write sections, such as the data section and stack,
532 are still copied to RAM. The XIP kernel is not compressed since
533 it has to run directly from flash, so it will take more space to
534 store it. The flash address used to link the kernel object files,
535 and for storing it, is configuration dependent. Therefore, if you
536 say Y here, you must know the proper physical address where to
537 store the kernel image depending on your own flash memory usage.
538
539 Also note that the make target becomes "make xipImage" rather than
540 "make zImage" or "make Image". The final kernel binary to put in
541 ROM memory will be arch/riscv/boot/xipImage.
542
543 SPARSEMEM is required because the kernel text and rodata that are
544 flash resident are not backed by memmap, then any attempt to get
545 a struct page on those regions will trigger a fault.
546
547 If unsure, say N.
548
549config XIP_PHYS_ADDR
550 hex "XIP Kernel Physical Location"
551 depends on XIP_KERNEL
552 default "0x21000000"
553 help
554 This is the physical address in your flash memory the kernel will
555 be linked for and stored to. This address is dependent on your
556 own flash usage.
557
558endmenu
559
560config BUILTIN_DTB
561 bool
562 depends on OF
563 default y if XIP_KERNEL
564
565menu "Power management options"
566
567source "kernel/power/Kconfig"
568
569endmenu
570