Start by elaborating on what some of our constraints tend to be with
image location values, and document where these external constraints
can come from. Provide a new subsection, an example based on the TI
ARMv7 OMAP2PLUS families of chips, that gives sample values and explains
why we use these particular values. This is based on what is in
include/configs/ti_armv7_common.h as of fb3ad9bd92 ("TI: Add, use a
DEFAULT_LINUX_BOOT_ENV environment string") as this contains just the
values referenced in this document now and not some of the further
additions that are less generic.
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
- Explain why fdt_addr and initrd_addr should not be set to disable
relocation normally.
- Provide some advice on the typical loadaddr default value.
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This variable is never set nor explained why it would be set, drop it.
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
"valu" should be "value".
Signed-off-by: Chris Packham <judge.packham@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Drop this text at the end since it already mentions bootp and dhcp.
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This doesn't really make much sense in the documentation. Add a code
comment instead.
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Simon Glass <sjg@chromium.org>
This has different semantics in different places. Go with the bootm method
and put it in a common function so that the behaviour is consistent in
U-Boot. Update the docs.
To be clear, this changes the way that 'bootelf' and standalone boot
work. Before, if autostart was set to "fred" or "YES", for example, they
would consider that a "yes". This may change behaviour for some boards,
but the only in-tree boards which mention autostart use "no" to disable
it, which will still work.
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Wolfgang Denk <wd@denx.de>
Make various other updates suggested during review of the rST conversion.
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Make various updates suggested during review of the rST conversion.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Suggested-by: Wolfgang Denk <wd@denx.de>
Add mention of this option since it does a similar thing to the text
environment.
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
At present U-Boot environment variables, and thus scripts, are defined
by CONFIG_EXTRA_ENV_SETTINGS. It is painful to add large amounts of text
to this file and dealing with quoting and newlines is harder than it
should be. It would be better if we could just type the script into a
text file and have it included by U-Boot.
Add a feature that brings in a .env file associated with the board
config, if present. To use it, create a file in a board/<vendor>
directory, typically called <board>.env and controlled by the
CONFIG_ENV_SOURCE_FILE option.
The environment variables should be of the form "var=value". Values can
extend to multiple lines. See the README under 'Environment Variables:'
for more information and an example.
In many cases environment variables need access to the U-Boot CONFIG
variables to select different options. Enable this so that the environment
scripts can be as useful as the ones currently in the board config files.
This uses the C preprocessor, means that comments can be included in the
environment using /* ... */
Also support += to allow variables to be appended to. This is needed when
using the preprocessor.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Tested-by: Marek Behún <marek.behun@nic.cz>
Move this from the README to rST format.
Drop i2cfast since it is obviously obsolete and breaks the formatting.
Other changes and improvements are in a following patch.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Marek Behún <marek.behun@nic.cz>
