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//env
directory called .env (or common.env if you want the same
environment for all boards).
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.
Comments are not permitted in the environment with this commit.
Signed-off-by: Simon Glass
---
Changes in v4:
- Move this from being part of configuring U-Boot to part of building it
- Don't put the environment in autoconf.mk as it is not needed
- Add documentation in rST format instead of README
- Drop mention of import/export
- Update awk script to ignore blank lines, as generated by clang
Changes in v3:
- Adjust Makefile to generate the .inc and .h files in separate fules
- Add more detail in the README about the format of .env files
- Improve the comment about " in the awk script
- Correctly terminate environment files with \n
Changes in v2:
- Move .env file from include/configs to board/
- Use awk script to process environment since it is much easier on the brain
- Add information and updated example script to README
- Add dependency rule so that the environment is rebuilt when it changes
Makefile | 34 ++-
config.mk | 2 ++
doc/usage/environment.rst | 41
env/embedded.c| 1 +
include/env_default.h | 8 +++
scripts/env2string.awk| 49 +++
6 files changed, 134 insertions(+), 1 deletion(-)
create mode 100644 scripts/env2string.awk
diff --git a/Makefile b/Makefile
index 3014788e14e..9e44af2ccb1 100644
--- a/Makefile
+++ b/Makefile
@@ -513,6 +513,7 @@ version_h := include/generated/version_autogenerated.h
timestamp_h := include/generated/timestamp_autogenerated.h
defaultenv_h := include/generated/defaultenv_autogenerated.h
dt_h := include/generated/dt.h
+env_h := include/generated/environment.h
no-dot-config-targets := clean clobber mrproper distclean \
help %docs check% coccicheck \
@@ -1802,6 +1803,37 @@ quiet_cmd_sym ?= SYM $@
u-boot.sym: u-boot FORCE
$(call if_changed,sym)
+# We expect '.env' but failing that will use 'common.env'
+ENV_DIR := $(if $(VENDOR),$(VENDOR)/env,$(BOARD)/env)
+ENV_FILE_BOARD := $(srctree)/board/${ENV_DIR}/$(BOARD).env
+ENV_FILE_COMMON := $(srctree)/board/${ENV_DIR}/common.env
+ENV_FILE := $(if $(wildcard
$(ENV_FILE_BOARD)),$(ENV_FILE_BOARD),$(ENV_FILE_COMMON))
+
+# Run the environment text file through the preprocessor
+quiet_cmd_gen_envp = ENVP$@
+ cmd_gen_envp = \
+ if [ -f "$(ENV_FILE)" ]; then \
+ cat $(ENV_FILE) >$@; \
+ else \
+ echo -n >$@ ; \
+ fi
+
+# Regenerate the environment if it changes
+# We use 'wildcard' since the file is not required to exist (at present), in
+# which case we don't want this dependency, but instead should create an empty
+# file
+include/generated/environment.in: \
+ $(if $(wildcard $(ENV_FILE)),$(wildcard $(ENV_FILE)),FORCE)
+ $(call cmd,gen_envp)
+
+quiet_cmd_gen_envt = ENVT$@
+ cmd_gen_envt = \
+ echo -n "\#define CONFIG_EXTRA_ENV_TEXT " >$@; \
+ awk -f $(srctree)/scripts/env2string.awk $< >>$@
+
+$(env_h): include/generated/environment.in
+ $(call cmd,gen_envt)
+
# The actual objects are generated when descending,
# make sure no implicit rule kicks in
$(sort $(u-boot-init) $(u-boot-main)): $(u-boot-dirs) ;
@@ -1857,7 +1889,7 @@ endif
# prepare2 creates a makefile if using a separate output directory
prepare2: prepare3 outputmakefile cfg
-prepare1: prepare2 $(version_h) $(timestamp_h) $(dt_h) \
+prepare1: prepare2 $(version_h) $(timestamp_h) $(dt_h) $(env_h) \
include/config/auto.conf
ifeq ($(wildcard $(LDSCRIPT)),)
@echo >&2 " Could not find linker script."
diff --git a/config.mk b/config.mk
index 7bb1fd4ed1b..2595aed218b 100644
--- a/config.mk
+++ b/config.mk
@@ -50,8 +50,10 @@ endif
ifneq ($(BOARD),)
ifdef VENDOR
BOARDDIR = $(VENDOR)/$(BOARD)
+ENVDIR=${vendor}/env
else
BOARDDIR = $(BOARD)
+ENVDIR=${board}/env
endif
endif
ifdef BOARD
diff --git a/doc/usage/environment.rst b/doc/usage/environment.rst
index be785a8f717..81130d17f85 100644
--- a/doc/usage/environment.rst
+++ b/doc/usage/environment.rst
@@ -14,6 +14,47 @@ environment. As long as you don't save the environment you
are
working with an in-memory copy. In case the Flash area containing the
environment is erased
