To enable support of hardware virtualization for ARM on the Arndale board,
the cpu needs to be prepared to enter the non-secure mode, as long as it does
not already run in it. Therefore, especially the interrupt controller and
some TrustZone specific system registers need to be prepared. Moreover,
the exception vector for the hypervisor needs to be set up properly, before
booting normally in the supervisor mode of the non-secure world.
Ref #1405
* name irq controller memory mapped I/O regions consistently
in board descriptions
* move irq controller and timer memory mapped I/O region descriptions
from cpu class to board class
* eliminate artificial distinction between flavors of ARM's GIC
* factor cpu local initialization out of ARM's GIC interface description,
which is needed if the GIC is initialized differently e.g. for TrustZone
Ref #1405
On Arndale, the kernel timer resets to the initial value of the last
count-down and continues as soon as it reaches zero. We must check this
via the interrupt status when we read out the timer value and in case
return 0 instead of the real value.
fix#1299
Kernel::Processor was a confusing remnant from the old scheme where we had a
Processor_driver (now Genode::Cpu) and a Processor (now Kernel::Cpu).
This commit also updates the in-code documentation and the variable and
function naming accordingly.
fix#1274
Previously, the timer was used to remember the state of the time slices.
This was sufficient before priorities entered the scene as a thread always
received a fresh time slice when he was scheduled away. However, with
priorities this isn't always the case. A thread can be preempted by another
thread due to a higher priority. In this case the low-priority thread must
remember how much time he has consumed from its current time slice because
the timer gets re-programmed. Otherwise, if we have high-priority threads
that block and unblock with high frequency, the head of the next lower
priority would start with a fresh time slice all the time and is never
superseded.
fix#1287