Add support for reading RTC clock from device tree using clock
framework also update the default calibration value to 0x7FFF
as per RTC specifications.

Falls back to 'calibration' property if clock unavailable, and uses
default calibration if neither is present. Only writes calibration when
hardware register reads zero.

The calibration write previously in zynqmp_rtc_set() has been moved to
the probe function. The earlier implementation wrote calibration on
every time update to clear the tick counter, but since calibration is
now dynamically configured from clock framework or device tree during probe,
it only requires one-time initialization. This avoids repeated tick
counter resets and unnecessary overhead.

Signed-off-by: Pranav Tilak <pranav.vinaytilak@amd.com>
Reviewed-by: Tomas Melin <tomas.melin@vaisala.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20260120110056.3640303-1-pranav.vinaytilak@amd.com

As part of bringing the master branch back in to next, we need to allow
for all of these changes to exist here.

Reported-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Tom Rini <trini@konsulko.com>

When bringing in the series 'arm: dts: am62-beagleplay: Fix Beagleplay
Ethernet"' I failed to notice that b4 noticed it was based on next and
so took that as the base commit and merged that part of next to master.

This reverts commit c8ffd1356d42223cbb8c86280a083cc3c93e6426, reversing
changes made to 2ee6f3a5f7550de3599faef9704e166e5dcace35.

Reported-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Tom Rini <trini@konsulko.com>

Remove <common.h> from this driver directory and when needed
add missing include files directly.

Signed-off-by: Tom Rini <trini@konsulko.com>

The whole driver logic is taken from Linux kernel but only set/get/reset
functions are implemented. When device is power off RTC is power out of
battery.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>