… initialization"

This reverts commit de4fad1.

Signed-off-by: Krzysztof Chruściński <[email protected]>

…ization

The GRTC counter is not cleared at startup, therefore the
`last_count` variable needs to be initialized accordingly.
This change:
- Prevents overflow of the `sys_clock_announce()` int32_t parameter
- Ensures the correct uptime value, which should be reset during
  initialization

Signed-off-by: Adam Kondraciuk <[email protected]>
(cherry picked from commit e77f942cff5516140f7db48bb42eda49522c1c7a)

…ister access

Speed up execution of the interrupt handler and sys_clock_set_timeout().
Sys_clock_set_timeout() can be called in two scenarios: from previous
timeout expiration handler or freely. If the former case fast path
can be used since CC value in the GRTC register just expired and it
can be used as a reference for CCADD setting. This is only a single
register write so it's much faster. In the latter a longer procedure
is applied which also happens in two variants. If value which is
set in CC is further in the future (e.g. K_FOREVER was set before) then
CC can be safely overwritten with a new value without a risk of
triggering unexpected COMPARE event. If value in CC is earlier than
the new CC value (if earlier timeout was aborted) then there is a
risk of COMPARE event happening while it is being overwritten.
That case requires long and safer procedure of setting CC.

Update hal_nordic with changes in the nrfx_grtc driver which are
needed for nrf_grtc_timer changes.

Upstream PR #: 87944

Signed-off-by: Krzysztof Chruściński <[email protected]>

Add stress test that randomly starts and aborts multiple timers
from various contexts. Test checks if timers do not expire prematurely.

Upstream PR #: 87944

Signed-off-by: Krzysztof Chruściński <[email protected]>