In QEMU, the Goldfish RTC is explicitly instantiated as a big-endian
device on the m68k virt machine (via the 'big-endian=true' property).
Currently, this driver uses ioread32() and iowrite32(), which works
by luck because the underlying readl() and writel() are currently
broken on m68k.

Use __raw_readl() and __raw_writel() instead to avoid breaking this
driver when the endianness of readl() and writel() is fixed.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Tested-by: Daniel Palmer <daniel@thingy.jp>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Daniel Palmer <daniel@thingy.jp>

Set the ops structure as static const. The structure is not accessible
from outside of this driver and is not going to be modified at runtime.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

Currently the oscillator stop flag (OSF) bit is never checked or cleared
on the DS1339 RTC chip.

On getting the time from the RTC, check if the OSF bit is set, log a
warning, and clear the flag. This matches the behavior of the DS1337
chip.

Note that the `date` command always reads from the RTC even when
setting or resetting the date, so the OSF flag is cleared in those cases
as well.

Signed-off-by: Ronan Dalton <ronan.dalton@alliedtelesis.co.nz>
Cc: Tom Rini <trini@konsulko.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Francesco Dolcini <francesco.dolcini@toradex.com>
Cc: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Simon Glass <sjg@chromium.org>

The DS1307 driver depends on DM_RTC since commit d425d6056e01 ("rtc: Add
DM support to ds1307"), remove the related obsolete code.

Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

The current code sets RV3028_STATUS_PORF instead of clearing it, so the
flag remains asserted. Use dm_i2c_reg_clrset() to clear the bit.

Signed-off-by: Javier Viguera <javier.viguera@digi.com>

Update the dependencies for RTC drivers which did not express a
requirement on DM_RTC, or in some cases on DM_RTC being disabled. In a
few cases, when DM_RTC is disabled we also require DM_I2C to also be
disabled or for POWER_LEGACY to be enabled.

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

At this point there are no users of this driver which do not enable
DM_RTC, so remove the legacy code and express the depdendency in
Kconfig. We can further remove code related to RTC chips / options that
are neither available in Kconfig nor set by any platforms.

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

The DS1338 RTC chip is supported in DM mode by the DS1307 driver, and at
this point all users have been using this functionality. It was a
function of Kconfig configuration that implied otherwise. Remove the
unused legacy symbols.

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

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

Currently, the Goldfish RTC driver exclusively relies on device tree
to retrieve the base address, failing immediately if dev_read_addr()
returns FDT_ADDR_T_NONE. This restriction prevents the driver from
being used on platforms that instantiate devices via U_BOOT_DRVINFO()
instead of device tree, such as the QEMU m68k virt machine.

Add support for platform data to address this limitation. Introduce a
new .of_to_plat hook to handle device tree parsing and populate the
platform data. Update the probe function to rely exclusively on this
platform data, enabling support for both Device Tree and manual
instantiation.

Introduce a new header file include/goldfish_rtc.h to define the
platform data structure.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>