The LMB module has undergone significant changes in the recent
past. Add a document which briefly describes what the LMB module does,
and the changes that have been made to it's design since the 2025.01
release.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Begin the work of documenting all of our pytests. To do this, we should
have a directory under develop for it as there will be a large number of
new files. As the current document is referenced externally in a number
of locations, add the sphinx_reredirects module so that we can redirect
from the old location to the new.

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

Convert the current miiphybb documentation to rst. Rename
the README.bitbangMII to bitbangmii.rst in the process.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

* format according to Sphinx style
* add link to Linux Kconfig documentation
* sort table alphabetically in 'Conversion from boards.cfg to Kconfig'

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

Provide a short description of how tests work, why they are so critical
and how to resolve gaps in Binman's test coverage.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

Simon Glass <sjg@chromium.org> says:

When the SPL build-phase was first created it was designed to solve a
particular problem (the need to init SDRAM so that U-Boot proper could
be loaded). It has since expanded to become an important part of U-Boot,
with three phases now present: TPL, VPL and SPL

Due to this history, the term 'SPL' is used to mean both a particular
phase (the one before U-Boot proper) and all the non-proper phases.
This has become confusing.

For a similar reason CONFIG_SPL_BUILD is set to 'y' for all 'SPL'
phases, not just SPL. So code which can only be compiled for actual SPL,
for example, must use something like this:

   #if defined(CONFIG_SPL_BUILD) && !defined(CONFIG_TPL_BUILD)

In Makefiles we have similar issues. SPL_ has been used as a variable
which expands to either SPL_ or nothing, to chose between options like
CONFIG_BLK and CONFIG_SPL_BLK. When TPL appeared, a new SPL_TPL variable
was created which expanded to 'SPL_', 'TPL_' or nothing. Later it was
updated to support 'VPL_' as well.

This series starts a change in terminology and usage to resolve the
above issues:

- The word 'xPL' is used instead of 'SPL' to mean a non-proper build
- A new CONFIG_XPL_BUILD define indicates that the current build is an
  'xPL' build
- The existing CONFIG_SPL_BUILD is changed to mean SPL; it is not now
  defined for TPL and VPL phases
- The existing SPL_ Makefile variable is renamed to SPL_
- The existing SPL_TPL Makefile variable is renamed to PHASE_

It should be noted that xpl_phase() can generally be used instead of
the above CONFIGs without a code-space or run-time penalty.

This series does not attempt to convert all of U-Boot to use this new
terminology but it makes a start. In particular, renaming spl.h and
common/spl seems like a bridge too far at this point.

The series is fully bisectable. It has also been checked to ensure there
are no code-size changes on any commit.

Move this section to rst, changing it just enough so that it builds.

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

Move this section of the README into doc/ with some minor updates to
mention SPL and user lower-case hex.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

This information is useful for people looking at how U-Boot has changed
over the years and the design decisions which led to it. Move it into
doc/ in an 'historical' section.

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

Before adding more files, move the bootstd docs into a new directory,
with an index.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>