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 ILLEGAL_POINTER_VALUE
94 default 0xdead000000000000
96 config LOCKDEP_SUPPORT
99 config TRACE_IRQFLAGS_SUPPORT
102 config RWSEM_XCHGADD_ALGORITHM
105 config GENERIC_HWEIGHT
111 config GENERIC_CALIBRATE_DELAY
117 config ARCH_DMA_ADDR_T_64BIT
120 config NEED_DMA_MAP_STATE
123 config NEED_SG_DMA_LENGTH
132 config FIX_EARLYCON_MEM
135 source "init/Kconfig"
137 source "kernel/Kconfig.freezer"
139 menu "Platform selection"
142 bool "ARMv8 software model (Versatile Express)"
143 select ARCH_REQUIRE_GPIOLIB
144 select COMMON_CLK_VERSATILE
145 select POWER_RESET_VEXPRESS
146 select VEXPRESS_CONFIG
148 This enables support for the ARMv8 software model (Versatile
152 bool "AppliedMicro X-Gene SOC Family"
154 This enables support for AppliedMicro X-Gene SOC Family
165 menu "Kernel Features"
167 menu "ARM errata workarounds"
169 config ARM64_ERRATUM_845719
170 bool "Cortex-A53: 845719: a load might read incorrect data"
174 This option adds an alternative code sequence to work around ARM
175 erratum 845719 on Cortex-A53 parts up to r0p4.
177 When running a compat (AArch32) userspace on an affected Cortex-A53
178 part, a load at EL0 from a virtual address that matches the bottom 32
179 bits of the virtual address used by a recent load at (AArch64) EL1
180 might return incorrect data.
182 The workaround is to write the contextidr_el1 register on exception
183 return to a 32-bit task.
184 Please note that this does not necessarily enable the workaround,
185 as it depends on the alternative framework, which will only patch
186 the kernel if an affected CPU is detected.
193 config ARM64_64K_PAGES
194 bool "Enable 64KB pages support"
196 This feature enables 64KB pages support (4KB by default)
197 allowing only two levels of page tables and faster TLB
198 look-up. AArch32 emulation is not available when this feature
201 config CPU_BIG_ENDIAN
202 bool "Build big-endian kernel"
204 Say Y if you plan on running a kernel in big-endian mode.
207 bool "Symmetric Multi-Processing"
208 select USE_GENERIC_SMP_HELPERS
210 This enables support for systems with more than one CPU. If
211 you say N here, the kernel will run on single and
212 multiprocessor machines, but will use only one CPU of a
213 multiprocessor machine. If you say Y here, the kernel will run
214 on many, but not all, single processor machines. On a single
215 processor machine, the kernel will run faster if you say N
218 If you don't know what to do here, say N.
221 bool "Multi-core scheduler support"
224 Multi-core scheduler support improves the CPU scheduler's decision
225 making when dealing with multi-core CPU chips at a cost of slightly
226 increased overhead in some places. If unsure say N here.
229 bool "SMT scheduler support"
232 Improves the CPU scheduler's decision making when dealing with
233 MultiThreading at a cost of slightly increased overhead in some
234 places. If unsure say N here.
236 config DISABLE_CPU_SCHED_DOMAIN_BALANCE
237 bool "(EXPERIMENTAL) Disable CPU level scheduler load-balancing"
239 Disables scheduler load-balancing at CPU sched domain level.
242 bool "(EXPERIMENTAL) Heterogenous multiprocessor scheduling"
243 depends on DISABLE_CPU_SCHED_DOMAIN_BALANCE && SCHED_MC && FAIR_GROUP_SCHED && !SCHED_AUTOGROUP
245 Experimental scheduler optimizations for heterogeneous platforms.
246 Attempts to introspectively select task affinity to optimize power
247 and performance. Basic support for multiple (>2) cpu types is in place,
248 but it has only been tested with two types of cpus.
249 There is currently no support for migration of task groups, hence
250 !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
251 between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
253 config SCHED_HMP_PRIO_FILTER
254 bool "(EXPERIMENTAL) Filter HMP migrations by task priority"
257 Enables task priority based HMP migration filter. Any task with
258 a NICE value above the threshold will always be on low-power cpus
259 with less compute capacity.
261 config SCHED_HMP_PRIO_FILTER_VAL
262 int "NICE priority threshold"
264 depends on SCHED_HMP_PRIO_FILTER
266 config HMP_FAST_CPU_MASK
267 string "HMP scheduler fast CPU mask"
270 Leave empty to use device tree information.
271 Specify the cpuids of the fast CPUs in the system as a list string,
272 e.g. cpuid 0+1 should be specified as 0-1.
274 config HMP_SLOW_CPU_MASK
275 string "HMP scheduler slow CPU mask"
278 Leave empty to use device tree information.
279 Specify the cpuids of the slow CPUs in the system as a list string,
280 e.g. cpuid 0+1 should be specified as 0-1.
282 config HMP_VARIABLE_SCALE
283 bool "Allows changing the load tracking scale through sysfs"
286 When turned on, this option exports the thresholds and load average
287 period value for the load tracking patches through sysfs.
288 The values can be modified to change the rate of load accumulation
289 and the thresholds used for HMP migration.
290 The load_avg_period_ms is the time in ms to reach a load average of
291 0.5 for an idle task of 0 load average ratio that start a busy loop.
292 The up_threshold and down_threshold is the value to go to a faster
293 CPU or to go back to a slower cpu.
294 The {up,down}_threshold are devided by 1024 before being compared
296 For examples, with load_avg_period_ms = 128 and up_threshold = 512,
297 a running task with a load of 0 will be migrated to a bigger CPU after
298 128ms, because after 128ms its load_avg_ratio is 0.5 and the real
300 This patch has the same behavior as changing the Y of the load
301 average computation to
302 (1002/1024)^(LOAD_AVG_PERIOD/load_avg_period_ms)
303 but it remove intermadiate overflows in computation.
305 config HMP_FREQUENCY_INVARIANT_SCALE
306 bool "(EXPERIMENTAL) Frequency-Invariant Tracked Load for HMP"
307 depends on HMP_VARIABLE_SCALE && CPU_FREQ
309 Scales the current load contribution in line with the frequency
310 of the CPU that the task was executed on.
311 In this version, we use a simple linear scale derived from the
312 maximum frequency reported by CPUFreq.
313 Restricting tracked load to be scaled by the CPU's frequency
314 represents the consumption of possible compute capacity
315 (rather than consumption of actual instantaneous capacity as
316 normal) and allows the HMP migration's simple threshold
317 migration strategy to interact more predictably with CPUFreq's
318 asynchronous compute capacity changes.
320 config SCHED_HMP_LITTLE_PACKING
321 bool "Small task packing for HMP"
325 Allows the HMP Scheduler to pack small tasks into CPUs in the
327 Controlled by two sysfs files in sys/kernel/hmp.
328 packing_enable: 1 to enable, 0 to disable packing. Default 1.
329 packing_limit: runqueue load ratio where a RQ is considered
330 to be full. Default is NICE_0_LOAD * 9/8.
333 int "Maximum number of CPUs (2-32)"
336 # These have to remain sorted largest to smallest
340 bool "Support for hot-pluggable CPUs"
343 Say Y here to experiment with turning CPUs off and on. CPUs
344 can be controlled through /sys/devices/system/cpu.
347 bool "Emulate SWP/SWPB instructions"
349 ARMv6 architecture deprecates use of the SWP/SWPB instructions. ARMv8
350 oblosetes the use of SWP/SWPB instructions. ARMv7 multiprocessing
351 extensions introduce the ability to disable these instructions,
352 triggering an undefined instruction exception when executed. Say Y
353 here to enable software emulation of these instructions for userspace
354 (not kernel) using LDREX/STREX. Also creates /proc/cpu/swp_emulation
357 In some older versions of glibc [<=2.8] SWP is used during futex
358 trylock() operations with the assumption that the code will not
359 be preempted. This invalid assumption may be more likely to fail
360 with SWP emulation enabled, leading to deadlock of the user
363 NOTE: when accessing uncached shared regions, LDREX/STREX rely
364 on an external transaction monitoring block called a global
365 monitor to maintain update atomicity. If your system does not
366 implement a global monitor, this option can cause programs that
367 perform SWP operations to uncached memory to deadlock.
371 source kernel/Kconfig.preempt
377 config ARCH_HAS_HOLES_MEMORYMODEL
378 def_bool y if SPARSEMEM
380 config ARCH_SPARSEMEM_ENABLE
382 select SPARSEMEM_VMEMMAP_ENABLE
384 config ARCH_SPARSEMEM_DEFAULT
385 def_bool ARCH_SPARSEMEM_ENABLE
387 config ARCH_SELECT_MEMORY_MODEL
388 def_bool ARCH_SPARSEMEM_ENABLE
390 config HAVE_ARCH_PFN_VALID
391 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
393 config HW_PERF_EVENTS
394 bool "Enable hardware performance counter support for perf events"
395 depends on PERF_EVENTS
398 Enable hardware performance counter support for perf events. If
399 disabled, perf events will use software events only.
401 config SYS_SUPPORTS_HUGETLBFS
404 config ARCH_WANT_GENERAL_HUGETLB
407 config ARCH_WANT_HUGE_PMD_SHARE
408 def_bool y if !ARM64_64K_PAGES
410 config HAVE_ARCH_TRANSPARENT_HUGEPAGE
414 bool "Kernel support for ARMv7 applications"
418 This option enables features that allow that ran on an ARMv7 or older
419 processor to continue functioning.
421 If you want to execute ARMv7 applications, say Y
423 config ARMV7_COMPAT_CPUINFO
424 bool "Report backwards compatible cpu features in /proc/cpuinfo"
425 depends on ARMV7_COMPAT
428 This option makes /proc/cpuinfo list CPU features that an ARMv7 or
429 earlier kernel would report, but are not optional on an ARMv8 or later
432 If you want to execute ARMv7 applications, say Y
436 config FORCE_MAX_ZONEORDER
438 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
442 bool "Enable seccomp to safely compute untrusted bytecode"
444 This kernel feature is useful for number crunching applications
445 that may need to compute untrusted bytecode during their
446 execution. By using pipes or other transports made available to
447 the process as file descriptors supporting the read/write
448 syscalls, it's possible to isolate those applications in
449 their own address space using seccomp. Once seccomp is
450 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
451 and the task is only allowed to execute a few safe syscalls
452 defined by each seccomp mode.
459 string "Default kernel command string"
462 Provide a set of default command-line options at build time by
463 entering them here. As a minimum, you should specify the the
464 root device (e.g. root=/dev/nfs).
467 prompt "Kernel command line type" if CMDLINE != ""
468 default CMDLINE_FROM_BOOTLOADER
470 config CMDLINE_FROM_BOOTLOADER
471 bool "Use bootloader kernel arguments if available"
473 Uses the command-line options passed by the boot loader. If
474 the boot loader doesn't provide any, the default kernel command
475 string provided in CMDLINE will be used.
477 config CMDLINE_EXTEND
478 bool "Extend bootloader kernel arguments"
480 The command-line arguments provided by the boot loader will be
481 appended to the default kernel command string.
484 bool "Always use the default kernel command string"
486 Always use the default kernel command string, even if the boot
487 loader passes other arguments to the kernel.
488 This is useful if you cannot or don't want to change the
489 command-line options your boot loader passes to the kernel.
492 config BUILD_ARM64_APPENDED_DTB_IMAGE
493 bool "Build a concatenated Image.gz/dtb by default"
496 Enabling this option will cause a concatenated Image.gz and list of
497 DTBs to be built by default (instead of a standalone Image.gz.)
498 The image will built in arch/arm64/boot/Image.gz-dtb
500 config BUILD_ARM64_APPENDED_DTB_IMAGE_NAMES
501 string "Default dtb names"
502 depends on BUILD_ARM64_APPENDED_DTB_IMAGE
504 Space separated list of names of dtbs to append when
505 building a concatenated Image.gz-dtb.
508 bool "UEFI runtime support"
509 depends on OF && !CPU_BIG_ENDIAN
512 select EFI_PARAMS_FROM_FDT
515 This option provides support for runtime services provided
516 by UEFI firmware (such as non-volatile variables, realtime
517 clock, and platform reset). A UEFI stub is also provided to
518 allow the kernel to be booted as an EFI application. This
519 is only useful on systems that have UEFI firmware.
523 menu "Userspace binary formats"
525 source "fs/Kconfig.binfmt"
528 bool "Kernel support for 32-bit EL0"
529 depends on !ARM64_64K_PAGES
530 select COMPAT_BINFMT_ELF
532 select OLD_SIGSUSPEND3
533 select COMPAT_OLD_SIGACTION
535 This option enables support for a 32-bit EL0 running under a 64-bit
536 kernel at EL1. AArch32-specific components such as system calls,
537 the user helper functions, VFP support and the ptrace interface are
538 handled appropriately by the kernel.
540 If you want to execute 32-bit userspace applications, say Y.
542 config SYSVIPC_COMPAT
544 depends on COMPAT && SYSVIPC
548 menu "Power management options"
550 source "kernel/power/Kconfig"
552 source "drivers/cpufreq/Kconfig"
553 config ARCH_SUSPEND_POSSIBLE
556 config ARM64_CPU_SUSPEND
561 menu "CPU Power Management"
563 source "drivers/cpuidle/Kconfig"
569 source "drivers/Kconfig"
571 source "drivers/firmware/Kconfig"
575 source "arch/arm64/kvm/Kconfig"
577 source "arch/arm64/Kconfig.debug"
579 source "security/Kconfig"
581 source "crypto/Kconfig"
583 source "arch/arm64/crypto/Kconfig"