3 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
5 select ARCH_USE_CMPXCHG_LOCKREF
7 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
8 select ARCH_SUPPORTS_ATOMIC_RMW
9 select ARCH_HAS_GCOV_PROFILE_ALL
10 select ARCH_WANT_OPTIONAL_GPIOLIB
11 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
12 select ARCH_WANT_FRAME_POINTERS
17 select BUILDTIME_EXTABLE_SORT
18 select AUDIT_ARCH_COMPAT_GENERIC
19 select CLONE_BACKWARDS
21 select CPU_PM if (SUSPEND || CPU_IDLE)
22 select DCACHE_WORD_ACCESS
23 select GENERIC_ALLOCATOR
24 select GENERIC_CLOCKEVENTS
25 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
26 select GENERIC_CPU_AUTOPROBE
27 select GENERIC_EARLY_IOREMAP
29 select GENERIC_IRQ_PROBE
30 select GENERIC_IRQ_SHOW
31 select GENERIC_SMP_IDLE_THREAD
32 select GENERIC_STRNCPY_FROM_USER
33 select GENERIC_STRNLEN_USER
34 select GENERIC_TIME_VSYSCALL
35 select HARDIRQS_SW_RESEND
36 select HAVE_ARCH_JUMP_LABEL
38 select HAVE_ARCH_AUDITSYSCALL
39 select HAVE_ARCH_SECCOMP_FILTER
40 select HAVE_ARCH_TRACEHOOK
41 select HAVE_C_RECORDMCOUNT
42 select HAVE_CC_STACKPROTECTOR
43 select HAVE_DEBUG_BUGVERBOSE
44 select HAVE_DEBUG_KMEMLEAK
45 select HAVE_DMA_API_DEBUG
47 select HAVE_DMA_CONTIGUOUS
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_EFFICIENT_UNALIGNED_ACCESS
50 select HAVE_FTRACE_MCOUNT_RECORD
51 select HAVE_FUNCTION_TRACER
52 select HAVE_FUNCTION_GRAPH_TRACER
53 select HAVE_GENERIC_DMA_COHERENT
54 select HAVE_GENERIC_HARDIRQS
55 select HAVE_HW_BREAKPOINT if PERF_EVENTS
57 select HAVE_PATA_PLATFORM
58 select HAVE_PERF_EVENTS
60 select HAVE_PERF_USER_STACK_DUMP
61 select HAVE_SYSCALL_TRACEPOINTS
63 select MODULES_USE_ELF_RELA
66 select OF_EARLY_FLATTREE
67 select OF_RESERVED_MEM
68 select PERF_USE_VMALLOC
73 select SYSCTL_EXCEPTION_TRACE
75 ARM 64-bit (AArch64) Linux support.
80 config ARCH_PHYS_ADDR_T_64BIT
89 config STACKTRACE_SUPPORT
92 config LOCKDEP_SUPPORT
95 config TRACE_IRQFLAGS_SUPPORT
98 config RWSEM_XCHGADD_ALGORITHM
101 config GENERIC_HWEIGHT
107 config GENERIC_CALIBRATE_DELAY
113 config ARCH_DMA_ADDR_T_64BIT
116 config NEED_DMA_MAP_STATE
119 config NEED_SG_DMA_LENGTH
128 config FIX_EARLYCON_MEM
131 source "init/Kconfig"
133 source "kernel/Kconfig.freezer"
135 menu "Platform selection"
138 bool "ARMv8 software model (Versatile Express)"
139 select ARCH_REQUIRE_GPIOLIB
140 select COMMON_CLK_VERSATILE
141 select POWER_RESET_VEXPRESS
142 select VEXPRESS_CONFIG
144 This enables support for the ARMv8 software model (Versatile
148 bool "AppliedMicro X-Gene SOC Family"
150 This enables support for AppliedMicro X-Gene SOC Family
161 menu "Kernel Features"
163 menu "ARM errata workarounds"
165 config ARM64_ERRATUM_845719
166 bool "Cortex-A53: 845719: a load might read incorrect data"
170 This option adds an alternative code sequence to work around ARM
171 erratum 845719 on Cortex-A53 parts up to r0p4.
173 When running a compat (AArch32) userspace on an affected Cortex-A53
174 part, a load at EL0 from a virtual address that matches the bottom 32
175 bits of the virtual address used by a recent load at (AArch64) EL1
176 might return incorrect data.
178 The workaround is to write the contextidr_el1 register on exception
179 return to a 32-bit task.
180 Please note that this does not necessarily enable the workaround,
181 as it depends on the alternative framework, which will only patch
182 the kernel if an affected CPU is detected.
189 config ARM64_64K_PAGES
190 bool "Enable 64KB pages support"
192 This feature enables 64KB pages support (4KB by default)
193 allowing only two levels of page tables and faster TLB
194 look-up. AArch32 emulation is not available when this feature
197 config CPU_BIG_ENDIAN
198 bool "Build big-endian kernel"
200 Say Y if you plan on running a kernel in big-endian mode.
203 bool "Symmetric Multi-Processing"
204 select USE_GENERIC_SMP_HELPERS
206 This enables support for systems with more than one CPU. If
207 you say N here, the kernel will run on single and
208 multiprocessor machines, but will use only one CPU of a
209 multiprocessor machine. If you say Y here, the kernel will run
210 on many, but not all, single processor machines. On a single
211 processor machine, the kernel will run faster if you say N
214 If you don't know what to do here, say N.
217 bool "Multi-core scheduler support"
220 Multi-core scheduler support improves the CPU scheduler's decision
221 making when dealing with multi-core CPU chips at a cost of slightly
222 increased overhead in some places. If unsure say N here.
225 bool "SMT scheduler support"
228 Improves the CPU scheduler's decision making when dealing with
229 MultiThreading at a cost of slightly increased overhead in some
230 places. If unsure say N here.
232 config DISABLE_CPU_SCHED_DOMAIN_BALANCE
233 bool "(EXPERIMENTAL) Disable CPU level scheduler load-balancing"
235 Disables scheduler load-balancing at CPU sched domain level.
238 bool "(EXPERIMENTAL) Heterogenous multiprocessor scheduling"
239 depends on DISABLE_CPU_SCHED_DOMAIN_BALANCE && SCHED_MC && FAIR_GROUP_SCHED && !SCHED_AUTOGROUP
241 Experimental scheduler optimizations for heterogeneous platforms.
242 Attempts to introspectively select task affinity to optimize power
243 and performance. Basic support for multiple (>2) cpu types is in place,
244 but it has only been tested with two types of cpus.
245 There is currently no support for migration of task groups, hence
246 !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
247 between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
249 config SCHED_HMP_PRIO_FILTER
250 bool "(EXPERIMENTAL) Filter HMP migrations by task priority"
253 Enables task priority based HMP migration filter. Any task with
254 a NICE value above the threshold will always be on low-power cpus
255 with less compute capacity.
257 config SCHED_HMP_PRIO_FILTER_VAL
258 int "NICE priority threshold"
260 depends on SCHED_HMP_PRIO_FILTER
262 config HMP_FAST_CPU_MASK
263 string "HMP scheduler fast CPU mask"
266 Leave empty to use device tree information.
267 Specify the cpuids of the fast CPUs in the system as a list string,
268 e.g. cpuid 0+1 should be specified as 0-1.
270 config HMP_SLOW_CPU_MASK
271 string "HMP scheduler slow CPU mask"
274 Leave empty to use device tree information.
275 Specify the cpuids of the slow CPUs in the system as a list string,
276 e.g. cpuid 0+1 should be specified as 0-1.
278 config HMP_VARIABLE_SCALE
279 bool "Allows changing the load tracking scale through sysfs"
282 When turned on, this option exports the thresholds and load average
283 period value for the load tracking patches through sysfs.
284 The values can be modified to change the rate of load accumulation
285 and the thresholds used for HMP migration.
286 The load_avg_period_ms is the time in ms to reach a load average of
287 0.5 for an idle task of 0 load average ratio that start a busy loop.
288 The up_threshold and down_threshold is the value to go to a faster
289 CPU or to go back to a slower cpu.
290 The {up,down}_threshold are devided by 1024 before being compared
292 For examples, with load_avg_period_ms = 128 and up_threshold = 512,
293 a running task with a load of 0 will be migrated to a bigger CPU after
294 128ms, because after 128ms its load_avg_ratio is 0.5 and the real
296 This patch has the same behavior as changing the Y of the load
297 average computation to
298 (1002/1024)^(LOAD_AVG_PERIOD/load_avg_period_ms)
299 but it remove intermadiate overflows in computation.
301 config HMP_FREQUENCY_INVARIANT_SCALE
302 bool "(EXPERIMENTAL) Frequency-Invariant Tracked Load for HMP"
303 depends on HMP_VARIABLE_SCALE && CPU_FREQ
305 Scales the current load contribution in line with the frequency
306 of the CPU that the task was executed on.
307 In this version, we use a simple linear scale derived from the
308 maximum frequency reported by CPUFreq.
309 Restricting tracked load to be scaled by the CPU's frequency
310 represents the consumption of possible compute capacity
311 (rather than consumption of actual instantaneous capacity as
312 normal) and allows the HMP migration's simple threshold
313 migration strategy to interact more predictably with CPUFreq's
314 asynchronous compute capacity changes.
316 config SCHED_HMP_LITTLE_PACKING
317 bool "Small task packing for HMP"
321 Allows the HMP Scheduler to pack small tasks into CPUs in the
323 Controlled by two sysfs files in sys/kernel/hmp.
324 packing_enable: 1 to enable, 0 to disable packing. Default 1.
325 packing_limit: runqueue load ratio where a RQ is considered
326 to be full. Default is NICE_0_LOAD * 9/8.
329 int "Maximum number of CPUs (2-32)"
332 # These have to remain sorted largest to smallest
336 bool "Support for hot-pluggable CPUs"
339 Say Y here to experiment with turning CPUs off and on. CPUs
340 can be controlled through /sys/devices/system/cpu.
343 bool "Emulate SWP/SWPB instructions"
345 ARMv6 architecture deprecates use of the SWP/SWPB instructions. ARMv8
346 oblosetes the use of SWP/SWPB instructions. ARMv7 multiprocessing
347 extensions introduce the ability to disable these instructions,
348 triggering an undefined instruction exception when executed. Say Y
349 here to enable software emulation of these instructions for userspace
350 (not kernel) using LDREX/STREX. Also creates /proc/cpu/swp_emulation
353 In some older versions of glibc [<=2.8] SWP is used during futex
354 trylock() operations with the assumption that the code will not
355 be preempted. This invalid assumption may be more likely to fail
356 with SWP emulation enabled, leading to deadlock of the user
359 NOTE: when accessing uncached shared regions, LDREX/STREX rely
360 on an external transaction monitoring block called a global
361 monitor to maintain update atomicity. If your system does not
362 implement a global monitor, this option can cause programs that
363 perform SWP operations to uncached memory to deadlock.
367 source kernel/Kconfig.preempt
373 config ARCH_HAS_HOLES_MEMORYMODEL
374 def_bool y if SPARSEMEM
376 config ARCH_SPARSEMEM_ENABLE
378 select SPARSEMEM_VMEMMAP_ENABLE
380 config ARCH_SPARSEMEM_DEFAULT
381 def_bool ARCH_SPARSEMEM_ENABLE
383 config ARCH_SELECT_MEMORY_MODEL
384 def_bool ARCH_SPARSEMEM_ENABLE
386 config HAVE_ARCH_PFN_VALID
387 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
389 config HW_PERF_EVENTS
390 bool "Enable hardware performance counter support for perf events"
391 depends on PERF_EVENTS
394 Enable hardware performance counter support for perf events. If
395 disabled, perf events will use software events only.
397 config SYS_SUPPORTS_HUGETLBFS
400 config ARCH_WANT_GENERAL_HUGETLB
403 config ARCH_WANT_HUGE_PMD_SHARE
404 def_bool y if !ARM64_64K_PAGES
406 config HAVE_ARCH_TRANSPARENT_HUGEPAGE
410 bool "Kernel support for ARMv7 applications"
414 This option enables features that allow that ran on an ARMv7 or older
415 processor to continue functioning.
417 If you want to execute ARMv7 applications, say Y
419 config ARMV7_COMPAT_CPUINFO
420 bool "Report backwards compatible cpu features in /proc/cpuinfo"
421 depends on ARMV7_COMPAT
424 This option makes /proc/cpuinfo list CPU features that an ARMv7 or
425 earlier kernel would report, but are not optional on an ARMv8 or later
428 If you want to execute ARMv7 applications, say Y
432 config FORCE_MAX_ZONEORDER
434 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
438 bool "Enable seccomp to safely compute untrusted bytecode"
440 This kernel feature is useful for number crunching applications
441 that may need to compute untrusted bytecode during their
442 execution. By using pipes or other transports made available to
443 the process as file descriptors supporting the read/write
444 syscalls, it's possible to isolate those applications in
445 their own address space using seccomp. Once seccomp is
446 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
447 and the task is only allowed to execute a few safe syscalls
448 defined by each seccomp mode.
455 string "Default kernel command string"
458 Provide a set of default command-line options at build time by
459 entering them here. As a minimum, you should specify the the
460 root device (e.g. root=/dev/nfs).
463 prompt "Kernel command line type" if CMDLINE != ""
464 default CMDLINE_FROM_BOOTLOADER
466 config CMDLINE_FROM_BOOTLOADER
467 bool "Use bootloader kernel arguments if available"
469 Uses the command-line options passed by the boot loader. If
470 the boot loader doesn't provide any, the default kernel command
471 string provided in CMDLINE will be used.
473 config CMDLINE_EXTEND
474 bool "Extend bootloader kernel arguments"
476 The command-line arguments provided by the boot loader will be
477 appended to the default kernel command string.
480 bool "Always use the default kernel command string"
482 Always use the default kernel command string, even if the boot
483 loader passes other arguments to the kernel.
484 This is useful if you cannot or don't want to change the
485 command-line options your boot loader passes to the kernel.
488 config BUILD_ARM64_APPENDED_DTB_IMAGE
489 bool "Build a concatenated Image.gz/dtb by default"
492 Enabling this option will cause a concatenated Image.gz and list of
493 DTBs to be built by default (instead of a standalone Image.gz.)
494 The image will built in arch/arm64/boot/Image.gz-dtb
496 config BUILD_ARM64_APPENDED_DTB_IMAGE_NAMES
497 string "Default dtb names"
498 depends on BUILD_ARM64_APPENDED_DTB_IMAGE
500 Space separated list of names of dtbs to append when
501 building a concatenated Image.gz-dtb.
504 bool "UEFI runtime support"
505 depends on OF && !CPU_BIG_ENDIAN
508 select EFI_PARAMS_FROM_FDT
511 This option provides support for runtime services provided
512 by UEFI firmware (such as non-volatile variables, realtime
513 clock, and platform reset). A UEFI stub is also provided to
514 allow the kernel to be booted as an EFI application. This
515 is only useful on systems that have UEFI firmware.
519 menu "Userspace binary formats"
521 source "fs/Kconfig.binfmt"
524 bool "Kernel support for 32-bit EL0"
525 depends on !ARM64_64K_PAGES
526 select COMPAT_BINFMT_ELF
528 select OLD_SIGSUSPEND3
529 select COMPAT_OLD_SIGACTION
531 This option enables support for a 32-bit EL0 running under a 64-bit
532 kernel at EL1. AArch32-specific components such as system calls,
533 the user helper functions, VFP support and the ptrace interface are
534 handled appropriately by the kernel.
536 If you want to execute 32-bit userspace applications, say Y.
538 config SYSVIPC_COMPAT
540 depends on COMPAT && SYSVIPC
544 menu "Power management options"
546 source "kernel/power/Kconfig"
548 source "drivers/cpufreq/Kconfig"
549 config ARCH_SUSPEND_POSSIBLE
552 config ARM64_CPU_SUSPEND
557 menu "CPU Power Management"
559 source "drivers/cpuidle/Kconfig"
565 source "drivers/Kconfig"
567 source "drivers/firmware/Kconfig"
571 source "arch/arm64/kvm/Kconfig"
573 source "arch/arm64/Kconfig.debug"
575 source "security/Kconfig"
577 source "crypto/Kconfig"
579 source "arch/arm64/crypto/Kconfig"