Allow SCSI to be able to store environment variables.

Signed-off-by: Varadarajan Narayanan <quic_varada@quicinc.com>
Acked-by: Casey Connolly <casey.connolly@linaro.org>

Introduce support for env in generic MTD. Currently we only support SPI
flash based on the lagacy sf cmd that assume SPI flash are always NOR.
This is not the case as to SPI controller also NAND can be attached.

To support also these flash scenario, add support for storing and
reading ENV from generic MTD device by adding an env driver that
base entirely on the MTD api.

Introduce a new kconfig CONFIG_ENV_IS_IN_MTD and
CONFIG_ENV_MTD_DEV to define the name of the MTD device as exposed
by mtd list.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

Use PHASE_ as the symbol to select a particular XPL build. This means
that SPL_TPL_ is no-longer set.

Update the comment in bootstage to refer to this symbol, instead of
SPL_

Signed-off-by: Simon Glass <sjg@chromium.org>

Complete this rename for all directories outside arch/ board/ drivers/
and include/

Use the new symbol to refer to any 'SPL' build, including TPL and VPL

Signed-off-by: Simon Glass <sjg@chromium.org>

This is not used anywhere, so drop it.

Signed-off-by: Simon Glass <sjg@chromium.org>

- Drop CONFIG_BUILD_ENVCRC as this is never set directly but instead
  means ENV_IS_EMBEDDED, so reference that in code and rename the Makefile
  usage to BUILD_ENVCRC.
- Remove extra-$(CONFIG_ENV_IS_EMBEDDED) line as it could never be true,
  and likely why there is an extra- line for CONFIG_ENV_IS_IN_FLASH (the
  only use case today of embedded environments).
- With these slight changes we can then see that using the calculated
  symbol of ENV_IS_EMBEDDED is the right thing to use in any code which
  needs to know this situation and can remove CONFIG_ENV_IS_EMBEDDED
  entirely.

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

env.h says this about about callback declarations (U_BOOT_ENV_CALLBACK):

 * For SPL these are silently dropped to reduce code size, since environment
 * callbacks are not supported with SPL.

So env_callback_init() does a lot of work to not find anything in the
guaranteed empty env_clbk list. Drop callback.o entirely from the link
and stub out the only public function defined in callback.o. This cuts
about 600 bytes from the SPL on my ppc build.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Simon Glass <sjg@chromium.org>

I'm also seeing the build failure that commit

7d4776545b env: solve compilation error in SPL

tried to fix, namely that the reference to env_flags_validate from
env_htab cannot be satisfied when flags.o is not built in. However,
that commit got reverted by

d90fc9c3de Revert "env: solve compilation error in SPL"

Necessary, but not sufficient conditions to see this are

CONFIG_SPL=y (obviously)
CONFIG_SPL_ENV_SUPPORT=n (so flags.o does not get compiled)
CONFIG_SPL_LIBCOMMON_SUPPORT=y (so env/built-in.o is part of the SPL link)

Now, these are satisfied for e.g. imx6q_logic_defconfig. But that
builds just fine, and spl/u-boot-spl.map lists .data.env_htab among
the discarded (garbage collected) sections. Yet, on our
mpc8309-derived board, we do see the build failure, so perhaps the
linker works a bit differently on ppc than on ARM, or there's yet some
other configuration option needed to observe the break.

This is another attempt at solving it, which also cleans up
env/Makefile a bit: Introduce a def_bool y symbol CONFIG_ENV_SUPPORT
which complements CONFIG_(SPL/TPL)_SUPPORT. Then use
CONFIG_$(SPL_TPL_)ENV_SUPPORT to decide whether to include the five
basic env/*.o files. For attr.o, flags.o and callback.o, this
shouldn't change anything. Also, common.o and env.o still get
unconditionally built for U-boot proper. But for TPL/SPL, those two
are only included if CONFIG_(SPL/TPL)_SUPPORT is set.

Having that symbol should also allow simplifying conditionals such as

#if !defined(CONFIG_SPL_BUILD) || CONFIG_IS_ENABLED(ENV_SUPPORT)

found in drivers/reset/reset-socfpga.c to just
CONFIG_IS_ENABLED(ENV_SUPPORT).

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>

Add Kconfig options SPL_ENV_* and TPL_ENV_* and simplify Makefile.
This allows SPL/TPL image has different environment setting from
full feature U-Boot.

Signed-off-by: York Sun <york.sun@nxp.com>

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>