tree 9b52afe82c395da11f15614c7f370b26f886bf02
parent facdd1c64c478c1b372391d2e3acb94bbe9fd570
author Juan Castillo <juan.castillo@arm.com> 1404836441 +0100
committer Juan Castillo <juan.castillo@arm.com> 1448616860 +0000

Add a simple ARM SP805 watchdog driver

Based on SP805 Programmer's model (ARM DDI 0270B). This driver
provides three public APIs:

    void sp805_start(uintptr_t base, unsigned long ticks);
    void sp805_stop(uintptr_t base);
    void sp805_refresh(uintptr_t base, unsigned long ticks);

Upon start, the watchdog starts counting down from the number of
ticks specified. When the count reaches 0 an interrupt is triggered.
The watchdog restarts counting down from the number of ticks
specified. If the count reaches 0 again, the system is reset. A
mechanism to handle the interrupt has not been implemented. Instead,
the API to refresh the watchdog should be used instead to prevent a
system reset.

Change-Id: I799d53f8d1213b10b341a4a67fde6486e89a3dab