The NPCM730 and NPCM750 SoCs have three timer modules each holding five
timers and some shared registers (e.g. interrupt status).
Each timer runs at 25 MHz divided by a prescaler, and counts down from a
configurable initial value to zero. When zero is reached, the interrupt
flag for the timer is set, and the timer is disabled (one-shot mode) or
reloaded from its initial value (periodic mode).
This implementation is sufficient to boot a Linux kernel configured for
NPCM750. Note that the kernel does not seem to actually turn on the
interrupts.
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Havard Skinnemoen <hskinnemoen@google.com>
Message-id: 20200911052101.2602693-4-hskinnemoen@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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