This implements a driver using a RTC-based backing store for the DM
bootcount implementation.  The node configuring this feature will be
compatible with 'u-boot,bootcount-rtc' and the underlying RTC device
shall be reference through the property 'rtc'. An offset into the RTC
device's register space can be provided through the 'offset' property.

Tested on a RK3399-Q7 on a Flamingo carrier board using the SRAM area
of the carrier board's RV3029 RTC.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>

The original bootcount methods do not provide an interface to DM and
rely on a static configuration for I2C devices (e.g. bus, chip-addr,
etc. are configured through defines statically).  On a modern system
that exposes multiple devices in a DTS-configurable way, this is less
than optimal and a interface to DM-based devices will be desirable.

This adds a simple driver that is DM-aware and configurable via DTS.
If ambiguous (i.e. multiple bootcount-devices are present) the
/chosen/u-boot,bootcount-device property can be used to select one
bootcount device.

Initially, this provides support for the following DM devices:
 * RTC devices

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Klaus Goger <klaus.goger@theobroma-systems.com>

Add new Kconfig option, SYS_BOOTCOUNT_MAGIC, to select the boot
counter magic word. This can be useful ie. in case the entire
boot counter register is not usable.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Tom Rini <trini@konsulko.com>

Add ability to set environment bootlimit from Kconfig

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>

1947c2d2a0 introduces cache line flushes for the bootcounter, but if
the start address is not aligned then the flush causes warnings of
the form:

  CACHE: Misaligned operation at range [4030b7fc, 4030b83c]

Align both the start and end of the buffer (possibly crossing multiple
lines).

Fixes: 1947c2d2a0 ("bootcount: flush after storing the bootcounter")
Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
Acked-by: Stefano Babic <sbabic@denx.de>

If the bootcounter address is in a cached memory,
a flush of dcache must occur after updateing the bootcounter.

Issue found on i.MX6 where bootcounter is put into the internal
(cached) IRAM.

Signed-off-by: Stefano Babic <sbabic@denx.de>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

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

This converts CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC to Kconfig

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>

Migrate the users of CONFIG_SYS_BOOTCOUNT_ADDR to Kconfig.  We can
provide a default for BOOTCOUNT_AM33XX as that's a specific part of the
RTC in use.  We can also provide a default for ARCH_LS1043A and
ARCH_LS1021A as they had been previously calculated and their symbols
are in Kconfig.  In the case of other QE-enabled platforms, they are not
so we must update the relevant defconfig files.  The previous default
only applied in some cases, even on a specific SoC family.

Reviewed-by: Lukasz Majewski <lukma@denx.de>
Reviewed-by: Alex Kiernan <alex.kiernan@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>

Convert CONFIG_BOOTCOUNT_ALEN to Kconfig
Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>