Implement tickless
Implement tickless verification
Change tickless verify range, from event create to event trigger
enable ktimer tickless by default
kernel: conditional build of tickless scheduling
Modify tickless verification display
Fix tickless does not recover heart beat
Fix call tickless_verify_stop before start
mk: migrate to Kconfig for tickless
conditional build of tickless scheduling status tracker
irq: use PendSV to avoid disabling irq in context-switch
Move platform dependent codes from tickless_verify to hwtimer

Signed-off-by: Jim Huang <jserv@0xlab.org>
kernel: fix build failure because of tickless
Merge branch 'test-tickless'

Fixes #19
add southernbear in author list
Close IRQ in context switch to avoid abnormal sampling result

This abnormal sampling results from context switch processing in PendSV
being preempted by ktimer IRQ which triggers sampling event periodically.

Fixes #40

Signed-off-by: Jim Huang <jserv@0xlab.org>
save lr in each context switch and only compare last 4bits in lr

EXC_RETURN[4] in normal context differs from that in FPU context
Support FPU context handling.

Fixes #9

While context switching, FPU registers saving and restoring are
supported, and EXC_RETURN[4] in lr is used for identifying FPU context
and save/restore FPU registers if needed.
migrate namespace to queue rather than generic fifo

Fixes 44

Use explicit queue for implementation consistency
mk: unify the usage of  "chip" and "platform" for consistency

Fixes #21