Vineet Gupta dec2b2849c ARCv2: intc: Allow interruption by lowest priority interrupt ... ARC HS Cores support configurable multiple interrupt priorities of upto 16 levels. There is processor "interrupt preemption threshhold" in STATUS32.E[4:1] And several places need to set this up: 1. seed value as kernel is booting 2. seed value for user space programs 3. Arg to SLEEP instruction in idle task (what interrupt prio can wake) 4. Per-IRQ line prioirty (i.e. what is the priority of interrupt raised by a peripheral or timer or perf counter... Currently above sites use the highest priority 0. This can be potential problem when multiple priorities are supported. e.g. user space could only be interrupted by P0 interrupt, not others... So turn this over and instead make default interruption level to be the lowest priority possible 15. This should be fine even if there are fewer priority levels configured (say two: P0 HIGH, P1 LOW) This feature also effectively disables FIRQ feature if present in hardware config. With old code, a P0 interrupt would be FIRQ, needing special handling (ISR or Register Banks) which is NOT supported yet. Now it not be P0 (P15 or whatever is lowest prio) so FIRQ is not triggered. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>		2016-02-10 06:38:50 +05:30
..
asm	ARCv2: intc: Allow interruption by lowest priority interrupt	2016-02-10 06:38:50 +05:30
uapi/asm	ARC: mm: use generic macros _BITUL()/_AC()	2015-10-28 19:31:05 +05:30