3 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
4 select ARCH_WANT_OPTIONAL_GPIOLIB
5 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
6 select ARCH_WANT_FRAME_POINTERS
10 select CLONE_BACKWARDS
12 select GENERIC_CLOCKEVENTS
14 select GENERIC_IRQ_PROBE
15 select GENERIC_IRQ_SHOW
16 select GENERIC_SMP_IDLE_THREAD
17 select GENERIC_TIME_VSYSCALL
18 select HARDIRQS_SW_RESEND
19 select HAVE_ARCH_TRACEHOOK
20 select HAVE_DEBUG_BUGVERBOSE
21 select HAVE_DEBUG_KMEMLEAK
22 select HAVE_DMA_API_DEBUG
24 select HAVE_GENERIC_DMA_COHERENT
25 select HAVE_GENERIC_HARDIRQS
26 select HAVE_HW_BREAKPOINT if PERF_EVENTS
28 select HAVE_PERF_EVENTS
30 select MODULES_USE_ELF_RELA
33 select OF_EARLY_FLATTREE
34 select PERF_USE_VMALLOC
39 select SYSCTL_EXCEPTION_TRACE
41 ARM 64-bit (AArch64) Linux support.
46 config ARCH_PHYS_ADDR_T_64BIT
55 config STACKTRACE_SUPPORT
58 config LOCKDEP_SUPPORT
61 config TRACE_IRQFLAGS_SUPPORT
64 config GENERIC_LOCKBREAK
66 depends on SMP && PREEMPT
68 config RWSEM_GENERIC_SPINLOCK
71 config GENERIC_HWEIGHT
77 config GENERIC_CALIBRATE_DELAY
83 config ARCH_DMA_ADDR_T_64BIT
86 config NEED_DMA_MAP_STATE
89 config NEED_SG_DMA_LENGTH
100 source "kernel/Kconfig.freezer"
102 menu "Platform selection"
105 bool "ARMv8 software model (Versatile Express)"
106 select ARCH_REQUIRE_GPIOLIB
107 select COMMON_CLK_VERSATILE
108 select POWER_RESET_VEXPRESS
109 select VEXPRESS_CONFIG
111 This enables support for the ARMv8 software model (Versatile
123 menu "Kernel Features"
125 config ARM64_64K_PAGES
126 bool "Enable 64KB pages support"
128 This feature enables 64KB pages support (4KB by default)
129 allowing only two levels of page tables and faster TLB
130 look-up. AArch32 emulation is not available when this feature
134 bool "Symmetric Multi-Processing"
135 select USE_GENERIC_SMP_HELPERS
137 This enables support for systems with more than one CPU. If
138 you say N here, the kernel will run on single and
139 multiprocessor machines, but will use only one CPU of a
140 multiprocessor machine. If you say Y here, the kernel will run
141 on many, but not all, single processor machines. On a single
142 processor machine, the kernel will run faster if you say N
145 If you don't know what to do here, say N.
147 config ARM_CPU_TOPOLOGY
148 bool "Support CPU topology definition"
152 Support CPU topology definition, based on configuration
153 provided by the firmware.
156 bool "Multi-core scheduler support"
157 depends on ARM_CPU_TOPOLOGY
159 Multi-core scheduler support improves the CPU scheduler's decision
160 making when dealing with multi-core CPU chips at a cost of slightly
161 increased overhead in some places. If unsure say N here.
164 bool "SMT scheduler support"
165 depends on ARM_CPU_TOPOLOGY
167 Improves the CPU scheduler's decision making when dealing with
168 MultiThreading at a cost of slightly increased overhead in some
169 places. If unsure say N here.
171 config DISABLE_CPU_SCHED_DOMAIN_BALANCE
172 bool "(EXPERIMENTAL) Disable CPU level scheduler load-balancing"
174 Disables scheduler load-balancing at CPU sched domain level.
177 bool "(EXPERIMENTAL) Heterogenous multiprocessor scheduling"
178 depends on DISABLE_CPU_SCHED_DOMAIN_BALANCE && SCHED_MC && FAIR_GROUP_SCHED && !SCHED_AUTOGROUP
180 Experimental scheduler optimizations for heterogeneous platforms.
181 Attempts to introspectively select task affinity to optimize power
182 and performance. Basic support for multiple (>2) cpu types is in place,
183 but it has only been tested with two types of cpus.
184 There is currently no support for migration of task groups, hence
185 !SCHED_AUTOGROUP. Furthermore, normal load-balancing must be disabled
186 between cpus of different type (DISABLE_CPU_SCHED_DOMAIN_BALANCE).
188 config SCHED_HMP_PRIO_FILTER
189 bool "(EXPERIMENTAL) Filter HMP migrations by task priority"
192 Enables task priority based HMP migration filter. Any task with
193 a NICE value above the threshold will always be on low-power cpus
194 with less compute capacity.
196 config SCHED_HMP_PRIO_FILTER_VAL
197 int "NICE priority threshold"
199 depends on SCHED_HMP_PRIO_FILTER
201 config HMP_FAST_CPU_MASK
202 string "HMP scheduler fast CPU mask"
205 Leave empty to use device tree information.
206 Specify the cpuids of the fast CPUs in the system as a list string,
207 e.g. cpuid 0+1 should be specified as 0-1.
209 config HMP_SLOW_CPU_MASK
210 string "HMP scheduler slow CPU mask"
213 Leave empty to use device tree information.
214 Specify the cpuids of the slow CPUs in the system as a list string,
215 e.g. cpuid 0+1 should be specified as 0-1.
217 config HMP_VARIABLE_SCALE
218 bool "Allows changing the load tracking scale through sysfs"
221 When turned on, this option exports the thresholds and load average
222 period value for the load tracking patches through sysfs.
223 The values can be modified to change the rate of load accumulation
224 and the thresholds used for HMP migration.
225 The load_avg_period_ms is the time in ms to reach a load average of
226 0.5 for an idle task of 0 load average ratio that start a busy loop.
227 The up_threshold and down_threshold is the value to go to a faster
228 CPU or to go back to a slower cpu.
229 The {up,down}_threshold are devided by 1024 before being compared
231 For examples, with load_avg_period_ms = 128 and up_threshold = 512,
232 a running task with a load of 0 will be migrated to a bigger CPU after
233 128ms, because after 128ms its load_avg_ratio is 0.5 and the real
235 This patch has the same behavior as changing the Y of the load
236 average computation to
237 (1002/1024)^(LOAD_AVG_PERIOD/load_avg_period_ms)
238 but it remove intermadiate overflows in computation.
240 config HMP_FREQUENCY_INVARIANT_SCALE
241 bool "(EXPERIMENTAL) Frequency-Invariant Tracked Load for HMP"
242 depends on HMP_VARIABLE_SCALE && CPU_FREQ
244 Scales the current load contribution in line with the frequency
245 of the CPU that the task was executed on.
246 In this version, we use a simple linear scale derived from the
247 maximum frequency reported by CPUFreq.
248 Restricting tracked load to be scaled by the CPU's frequency
249 represents the consumption of possible compute capacity
250 (rather than consumption of actual instantaneous capacity as
251 normal) and allows the HMP migration's simple threshold
252 migration strategy to interact more predictably with CPUFreq's
253 asynchronous compute capacity changes.
255 config SCHED_HMP_LITTLE_PACKING
256 bool "Small task packing for HMP"
260 Allows the HMP Scheduler to pack small tasks into CPUs in the
262 Controlled by two sysfs files in sys/kernel/hmp.
263 packing_enable: 1 to enable, 0 to disable packing. Default 1.
264 packing_limit: runqueue load ratio where a RQ is considered
265 to be full. Default is NICE_0_LOAD * 9/8.
268 int "Maximum number of CPUs (2-32)"
274 bool "Support for hot-pluggable CPUs"
277 Say Y here to experiment with turning CPUs off and on. CPUs
278 can be controlled through /sys/devices/system/cpu.
280 source kernel/Kconfig.preempt
286 config ARCH_HAS_HOLES_MEMORYMODEL
287 def_bool y if SPARSEMEM
289 config ARCH_SPARSEMEM_ENABLE
291 select SPARSEMEM_VMEMMAP_ENABLE
293 config ARCH_SPARSEMEM_DEFAULT
294 def_bool ARCH_SPARSEMEM_ENABLE
296 config ARCH_SELECT_MEMORY_MODEL
297 def_bool ARCH_SPARSEMEM_ENABLE
299 config HAVE_ARCH_PFN_VALID
300 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
302 config HW_PERF_EVENTS
303 bool "Enable hardware performance counter support for perf events"
304 depends on PERF_EVENTS
307 Enable hardware performance counter support for perf events. If
308 disabled, perf events will use software events only.
317 string "Default kernel command string"
320 Provide a set of default command-line options at build time by
321 entering them here. As a minimum, you should specify the the
322 root device (e.g. root=/dev/nfs).
325 bool "Always use the default kernel command string"
327 Always use the default kernel command string, even if the boot
328 loader passes other arguments to the kernel.
329 This is useful if you cannot or don't want to change the
330 command-line options your boot loader passes to the kernel.
334 menu "Userspace binary formats"
336 source "fs/Kconfig.binfmt"
339 bool "Kernel support for 32-bit EL0"
340 depends on !ARM64_64K_PAGES
341 select COMPAT_BINFMT_ELF
343 select OLD_SIGSUSPEND3
344 select COMPAT_OLD_SIGACTION
346 This option enables support for a 32-bit EL0 running under a 64-bit
347 kernel at EL1. AArch32-specific components such as system calls,
348 the user helper functions, VFP support and the ptrace interface are
349 handled appropriately by the kernel.
351 If you want to execute 32-bit userspace applications, say Y.
353 config SYSVIPC_COMPAT
355 depends on COMPAT && SYSVIPC
359 menu "Power management options"
361 source "kernel/power/Kconfig"
363 source "drivers/cpufreq/Kconfig"
369 source "drivers/Kconfig"
373 source "arch/arm64/Kconfig.debug"
375 source "security/Kconfig"
377 source "crypto/Kconfig"