u-boot.git/include/env.h, branch v2022.01

env: Make return value of env_get_f() behave like sprintf() on success

2021-10-21T18:50:48+00:00

Currently the env_get_f() function's return value behaves weirdly: it
returns the number of bytes written into `buf`, but whether this is
excluding the terminating NULL-byte or including it depends on whether
there was enough space in `buf`.

Change the function to always return the actual length of the value of
the environment variable (excluding the terminating NULL-byte) on
success. This makes it behave like sprintf().

All users of this function in U-Boot are compatible with this change.

Signed-off-by: Marek Behún 
Reviewed-by: Simon Glass

env: Inline env_get_char() into its only user

2021-10-21T18:50:48+00:00

This function is a relic from the past when environment was read from
underlying device one character at a time.

It is used only in the case when getting an environemnt variable prior
relocation, and the function is simple enough to be inlined there.

Since env_get_char() is being changed to simple access to an array, we
can drop the failing cases and simplify the code (this could have been
done before, since env_get_char() did not fail even before).

Signed-off-by: Marek Behún 
Reviewed-by: Simon Glass

env: Change env_match() to static and remove from header

2021-10-21T18:50:48+00:00

This function was used by other parts of U-Boot in the past when
environment was read from underlying device one character at a time.

This is not the case anymore.

Signed-off-by: Marek Behún 
Reviewed-by: Simon Glass

env: Fix documentation for env_get_f()

2021-10-21T18:50:48+00:00

This function actually returns:
- the number of bytes written into @buf excluding the terminating
  NULL-byte, if there was enough space in @buf
- the number of bytes written into @buf including the terminating
  NULL-byte, if there wasn't enough space in @buf
- -1 if the variable is not found

Signed-off-by: Marek Behún 
Reviewed-by: Simon Glass

env: allow environment to be amended from control dtb

2021-05-04T15:50:50+00:00

It can be useful to use the same U-Boot binary for multiple purposes,
say the normal one, one for developers that allow breaking into the
U-Boot shell, and one for use during bootstrapping which runs a
special-purpose bootcmd. Or one can have several board variants that
can share almost all boot logic, but just needs a few tweaks in the
variables used by the boot script.

To that end, allow the control dtb to contain a /config/enviroment
node (or whatever one puts in fdt_env_path variable), whose
property/value pairs are used to update the run-time environment after
it has been loaded from its persistent location.

The indirection via fdt_env_path is for maximum flexibility - for
example, should the user wish (or board logic dictate) that the values
in the DTB should no longer be applied, one simply needs to delete the
fdt_env_path variable; that can even be done automatically by
including a

  fdt_env_path = "";

property in the DTB node.

Reviewed-by: Simon Glass 
Signed-off-by: Rasmus Villemoes 
Acked-by: Joe Hershberger

env: increment redund flag on read fail

2021-04-16T15:55:55+00:00

If one of the reads fails when importing redundant environments (a
single read failure), the env_flags wouldn't get initialized in
env_import_redund(). If a user then calls saveenv, the new environment
will have the wrong flags value. So on the next load the new environment
will be ignored.

While debugging this, I also noticed that env/sf.c was not correctly
handling a single read failure, as it would not check the crc before
assigning it to gd->env_addr.

Having a special error path for when there is a single read failure
seems unnecessary and may lead to future bugs. Instead collapse the
'single read failure' error to be the same as a 'single crc failure'.
That way env_check_redund() either passes or fails, and if it passes we
are guaranteed to have checked the CRC.

Signed-off-by: Brandon Maier 
CC: Joe Hershberger 
CC: Wolfgang Denk 
CC: Heiko Schocher 
Reviewed-by: Tom Rini

env: split env_import_redund() into 2 functions

2020-10-30T14:54:38+00:00

split from env_import_redund() the part which checks
which Environment is valid into a separate function
called env_check_redund() and call it from env_import_redund().

So env_check_redund() can be used from places which also
need to do this checks.

Signed-off-by: Heiko Schocher 
Reviewed-by: Simon Glass

env: Discern environment coming from external storage

2020-07-31T14:13:00+00:00

Add another custom environment flag which discerns environment coming
from external storage from environment set by U-Boot itself.

Signed-off-by: Marek Vasut 
Reviewed-by: Tom Rini

cmd: env: add env select command

2020-07-31T14:13:00+00:00

Add the new command 'env select' to force the persistent storage
of environment, saved in gd->env_load_prio.

Signed-off-by: Patrick Delaunay

cmd: env: add env load command

2020-07-31T14:13:00+00:00

Add the new command env load to load the environment from
the current location gd->env_load_prio.

Signed-off-by: Patrick Delaunay