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>

For multiple env drivers to correctly implement fallback when
one environment fails to load (e.g. crc error), the return value
of env_import has to be propagated by all env driver's load
function.

Without this change, the first driver that succeeds to load an
environment with an invalid CRC return 0 (success) and no other
drivers are checked.

Signed-off-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

There is more common code in mmc, nand and ubi env drivers that
can be shared by moving to env_import_redund.

For this, a status/error value whether the buffers were loaded
are passed as additional parameters to env_import_redund.
Ideally, these are already returned to the env driver by the
storage driver. This is the case for mmc, nand and ubi, so for
this change, code deduplicated.

Signed-off-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

The load() methods have inconsistent behaviour on error. Some of them load
an empty default environment. Some load an environment containing an error
message. Others do nothing.

As a step in the right direction, have the method return an error code.
Then the caller could handle this itself in a consistent way.

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

This variable is declared as a global in most environment location
drivers. But it is not used outside the drivers and most of the
declarations are unnecessary.

Also some drivers call free() on env_ptr which seems wrong since it is
not in the heap.

Drop the variable where possible, and all calls to free().

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

Add a name to the driver and use that instead of the global variable
declared by each driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

Most of the init() implementations just use the default environment.
Adjust env_init_new() to do this automatically, and drop the redundant
code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

Move over to use a the master implementation of the location drivers, with
each method calling out to the appropriate driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

Set up a location driver for each supported environment location. At
present this just points to the global functions and is not used. A
later patch will switch this over to use private functions in each driver.

There are several special cases here in various drivers to handle
peculiarities of certain boards:

1. Some boards define CONFIG_ENV_IS_IN_FAT and CONFIG_SPL_ENV_SUPPORT but
do not actually load the environment in SPL. The env load code was
optimised out before but with the driver, it is not. Therefore a special
case is added to env/fat.c. The correct fix (depending on board testing
might be to disable CONFIG_SPL_ENV_SUPPORT.

2. A similar situations happens with CONFIG_ENV_IS_IN_FLASH. Some boards
do not actually load the environment in SPL, so to reduce code size we
need to drop that code. A similar fix may be possible with these boards,
or it may be possible to adjust the environment CONFIG settings.

Added to the above is that the CONFIG_SPL_ENV_SUPPORT option does not
apply when the environment is in flash.

Obviously the above has been discovered through painful and time-consuming
trial and error. Hopefully board maintainers can take a look and figure
out what is actually needed.

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

At present we have three states for the environment, numbered 0, 1 and 2.
Add an enum to record this to avoid open-coded values.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

About a quarter of the files in common/ relate to the environment. It
seems better to put these into their own subdirectory and remove the
prefix.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

The env_nand, env_mmc and env_ubi implementations all implement
redundancy using an identical serial-number scheme. This commit
migrates them to use the implementation in env_common, which is
functionally identical.

Signed-off-by: Fiach Antaw <fiach.antaw@uqconnect.edu.au>
Reviewed-by: Tom Rini <trini@konsulko.com>

In case we have restarted u-boot there is a chance that environment
buffer contains old environment (from the previous boot). If UBI volume
is zero size, ubi_volume_read() doesn't modify the buffer and exits
successfully.

We need to clear buffer manually before reading it from UBI, so the
invalid CRC will cause setting default environment in case that the UBI
volume is zero size.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>

The variable "buf" in this function is a char array, and the
function ubi_volume_read is expecting a char *.  In the call, the
address of the pointer is being taken, incorrectly passing a
char **.  The compiler warning was being silenced by the cast.
Remove the address operator and the cast.

Signed-off-by: Kevin Smith <kevin.smith@elecsyscorp.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Tom Rini <trini@konsulko.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Heiko Schocher <hs@denx.de>

Now that we have a new header file for cache-aligned allocation, we should
move the stack-based allocation macro there also.

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

Implement env_export() wrapper, so that all implementers of saveenv() don't
have to call hexport_r(), crc32() etc. sequence . This trims down a bit of
code duplication.

Signed-off-by: Marek Vasut <marex@denx.de>

Signed-off-by: Wolfgang Denk <wd@denx.de>

Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>

Allow the user to specify two UBI volumes to use for the environment

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

UBI is a better place for the environment on NAND devices because it
handles wear-leveling and bad blocks.

Gluebi is needed in Linux to access the env as an MTD partition.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>