Allow providing default environment from file

It is sometimes useful to be able to define the entire default environment in an external file.

This implements a Kconfig option for
allowing that.

It is somewhat annoying to have two visible Kconfig options; it would probably be more user-friendly to just have the string option (with empty string obviously meaning not to use this feature). But then we'd also need a hidden CONFIG that we can use in the #ifdef in env_default.h, and I don't think one can set a def_bool based on whether a string-valued config is empty or not.

I've tried to make the accepted format the same as the one the mkenvimage tool accepts. I have no idea how portable the sed script implementing the "allow embedded newlines in values" is. Nor do I know if one can expect xxd to be available.

Signed-off-by Rasmus Villemoes <[email protected]>

---
 Makefile              | 16 ++++++++++++++++
 env/Kconfig           | 18 ++++++++++++++++++
 include/env_default.h |  4 ++++
 3 files changed, 38 insertions(+)

Makefile +16 -2

index 4981a2ed6f..e5ba5213fd 100644
@@ -423,6 +423,7 @@ endif
 
 version_h := include/generated/version_autogenerated.h
 timestamp_h := include/generated/timestamp_autogenerated.h
+defaultenv_h := include/generated/defaultenv_autogenerated.h
 
 no-dot-config-targets := clean clobber mrproper distclean \
 			 help %docs check% coccicheck \

@@ -1366,6 +1367,10 @@ ifeq ($(wildcard $(LDSCRIPT)),)
 	@/bin/false
 endif
 
+ifeq ($(CONFIG_DEFAULT_ENV_FROM_FILE),y)
+prepare1: $(defaultenv_h)
+endif
+
 archprepare: prepare1 scripts_basic
 
 prepare0: archprepare FORCE

@@ -1413,12 +1418,23 @@ define filechk_timestamp.h
 	fi)
 endef
 
+define filechk_defaultenv.h
+	(grep -v '^#' | \
+	 grep -v '^$$' | \
+	 tr '\n' '\0' | \
+	 sed -e 's/\\\x0/\n/' | \
+	 xxd -i ; echo ", 0x00" ; )
+endef
+
 $(version_h): include/config/uboot.release FORCE
 	$(call filechk,version.h)
 
 $(timestamp_h): $(srctree)/Makefile FORCE
 	$(call filechk,timestamp.h)
 
+$(defaultenv_h): $(CONFIG_DEFAULT_ENV_FILE:"%"=%) FORCE
+	$(call filechk,defaultenv.h)
+
 #
---------------------------------------------------------------------------
 quiet_cmd_cpp_lds = LDS     $@ cmd_cpp_lds = $(CPP)
-Wp,-MD,$(depfile) $(cpp_flags) $(LDPPFLAGS) \ diff --git

a/env/Kconfig b/env/Kconfig index a24370786b..1baebd743b 100644

env/Kconfig +4 -0

@@ -482,4 +482,22 @@ config ENV_SIZE
 
 endif
 
+config DEFAULT_ENV_FROM_FILE
+	bool "Create default environment from file"
+	help
+	  Normally, the default environment is automatically

generated

env/Kconfig +14 -0

+	  based on the settings of various CONFIG_* options, as well
+	  as the CONFIG_EXTRA_ENV_SETTINGS. By selecting this option,
+	  you can instead define the entire default environment in an
+	  external file.
+
+config DEFAULT_ENV_FILE
+	string "Path to default environment file"
+	depends on DEFAULT_ENV_FROM_FILE
+	help
+	  The path containing the default environment. The format is
+	  the same as accepted by the mkenvimage tool: lines
+	  containing key=value pairs, blank lines and lines beginning
+	  with # are ignored.
+
 endmenu

include/env_default.h +1 -0

index b574345af2..656d202cc7 100644
@@ -22,6 +22,7 @@ static char default_environment[] = {
 #else
 const uchar default_environment[] = {
 #endif
+#ifndef CONFIG_DEFAULT_ENV_FROM_FILE
 #ifdef	CONFIG_ENV_CALLBACK_LIST_DEFAULT
 	ENV_CALLBACK_VAR "=" CONFIG_ENV_CALLBACK_LIST_DEFAULT "\0"
 #endif

Hi Rasmus,

Quoted 2 lines

It is sometimes useful to be able to define the entire default environment in an external file.

There is already available script for extracting the environment.

Please look into:
./scripts/get_default_envs.sh

Maybe you can reuse it in this patch?

Quoted 7 lines

Hi Rasmus,

Quoted 2 lines

It is sometimes useful to be able to define the entire default environment in an external file.

There is already available script for extracting the environment.

Quoted 4 lines

Please look into:
./scripts/get_default_envs.sh

Maybe you can reuse it in this patch?

I'm sorry, but I don't see what I could use that for. It seems to do the opposite of what I want,

namely extract the default environment
and store it in a plain-text file. I want to provide a plain-text file to define the default environment.

It's quite likely that that script can be useful for generating a sketch for the external file (i.e., build a U-boot as "usual" with default environment built from various config options etc. etc., then hand-edit that file to remove redundant stuff and add the things one needs). The thing is, having the default environment in an external file makes it much easier to put it under version control than having to maintain a branch inside the U-boot repo just to tweak CONFIG_EXTRA_ENV_SETTINGS.

Rasmus

It is sometimes useful to be able to define the entire default environment in an external file. This implements a Kconfig option for allowing that.

It is somewhat annoying to have two visible Kconfig options; it would probably be more user-friendly to just have the string option (with empty string obviously meaning not to use this feature). But then we'd also need a hidden CONFIG that we can use in the #ifdef in env_default.h, and I don't think one can set a def_bool based on whether a string-valued config is empty or not.

I've tried to make the accepted format the same as the one the mkenvimage tool accepts. I have no idea how portable the sed script implementing the "allow embedded newlines in values" is. Nor do I know if one can expect xxd to be available.

Signed-off-by Rasmus Villemoes <[email protected]>

---
  Makefile              | 16 ++++++++++++++++
  env/Kconfig           | 18 ++++++++++++++++++
  include/env_default.h |  4 ++++
  3 files changed, 38 insertions(+)

Makefile +16 -0

index 4981a2ed6f..e5ba5213fd 100644
@@ -423,6 +423,7 @@ endif
 
  version_h := include/generated/version_autogenerated.h
  timestamp_h := include/generated/timestamp_autogenerated.h
+defaultenv_h := include/generated/defaultenv_autogenerated.h
 
  no-dot-config-targets := clean clobber mrproper distclean \
  			 help %docs check% coccicheck \

@@ -1366,6 +1367,10 @@ ifeq ($(wildcard $(LDSCRIPT)),)
  	@/bin/false
  endif
 
+ifeq ($(CONFIG_DEFAULT_ENV_FROM_FILE),y)
+prepare1: $(defaultenv_h)
+endif
+
  archprepare: prepare1 scripts_basic
 
  prepare0: archprepare FORCE

@@ -1413,12 +1418,23 @@ define filechk_timestamp.h
  	fi)
  endef
 
+define filechk_defaultenv.h
+	(grep -v '^#' | \
+	 grep -v '^$$' | \
+	 tr '\n' '\0' | \
+	 sed -e 's/\\\x0/\n/' | \
+	 xxd -i ; echo ", 0x00" ; )
+endef
+
  $(version_h): include/config/uboot.release FORCE
  	$(call filechk,version.h)
 
  $(timestamp_h): $(srctree)/Makefile FORCE
  	$(call filechk,timestamp.h)
 
+$(defaultenv_h): $(CONFIG_DEFAULT_ENV_FILE:"%"=%) FORCE
+	$(call filechk,defaultenv.h)
+
  # ---------------------------------------------------------------------------
  quiet_cmd_cpp_lds = LDS     $@
  cmd_cpp_lds = $(CPP) -Wp,-MD,$(depfile) $(cpp_flags) $(LDPPFLAGS) \

env/Kconfig +18 -0

index a24370786b..1baebd743b 100644
@@ -482,4 +482,22 @@ config ENV_SIZE
 
  endif
 
+config DEFAULT_ENV_FROM_FILE
+	bool "Create default environment from file"
+	help
+	  Normally, the default environment is automatically generated
+	  based on the settings of various CONFIG_* options, as well
+	  as the CONFIG_EXTRA_ENV_SETTINGS. By selecting this option,
+	  you can instead define the entire default environment in an
+	  external file.
+
+config DEFAULT_ENV_FILE
+	string "Path to default environment file"
+	depends on DEFAULT_ENV_FROM_FILE
+	help
+	  The path containing the default environment. The format is
+	  the same as accepted by the mkenvimage tool: lines
+	  containing key=value pairs, blank lines and lines beginning
+	  with # are ignored.
+
  endmenu

include/env_default.h +4 -0

index b574345af2..656d202cc7 100644
@@ -22,6 +22,7 @@ static char default_environment[] = {
  #else
  const uchar default_environment[] = {
  #endif
+#ifndef CONFIG_DEFAULT_ENV_FROM_FILE
  #ifdef	CONFIG_ENV_CALLBACK_LIST_DEFAULT
  	ENV_CALLBACK_VAR "=" CONFIG_ENV_CALLBACK_LIST_DEFAULT "\0"
  #endif

@@ -108,6 +109,9 @@ const uchar default_environment[] = {
  	CONFIG_EXTRA_ENV_SETTINGS
  #endif
  	"\0"
+#else /* CONFIG_DEFAULT_ENV_FROM_FILE */
+#include "generated/defaultenv_autogenerated.h"
+#endif
  #ifdef DEFAULT_ENV_INSTANCE_EMBEDDED
  	}
  #endif

It is sometimes useful to be able to define the entire default environment in an external file. This implements a Kconfig option for allowing that.

Quoted 3 lines · Rasmus Villemoes

It is sometimes useful to be able to define the entire default environment in an external file. This implements a Kconfig option for allowing that.

ping

It is sometimes useful to be able to define the entire default environment in an external file. This implements a Kconfig option for allowing that.

It is somewhat annoying to have two visible Kconfig options; it would probably be more user-friendly to just have the string option (with empty string obviously meaning not to use this feature). But then we'd also need a hidden CONFIG that we can use in the #ifdef in env_default.h, and I don't think one can set a def_bool based on whether a string-valued config is empty or not.

I've tried to make the accepted format the same as the one the mkenvimage tool accepts. I have no idea how portable the sed script implementing the "allow embedded newlines in values" is. Nor do I know if one can expect xxd to be available.

Signed-off-by Rasmus Villemoes <[email protected]>

---
 Makefile              | 16 ++++++++++++++++
 env/Kconfig           | 18 ++++++++++++++++++
 include/env_default.h |  4 ++++
 3 files changed, 38 insertions(+)

Modifying the default environment via CONFIG_EXTRA_ENV_SETTINGS is somewhat inflexible, partly because the cpp language does not allow appending to an existing macro. This prevents reuse of "environment fragments" for different boards, which in turn makes maintaining that environment consistently tedious and error-prone.

This implements a Kconfig option for allowing one to define the entire default environment in an external file, which can then, for example, be generated programmatically as part of a Yocto recipe,

or simply be
kept in version control separately from the U-boot repository.

Tested-by Sean Nyekjaer <[email protected]>

Signed-off-by Rasmus Villemoes <[email protected]>

---
v2:
* rename CONFIG_DEFAULT_ENV_FROM_FILE -> CONFIG_USE_DEFAULT_ENV_FILE
* add Tested-by
* provide a little more rationale (example use case instead of just "sometimes be useful")
* rebase to current master (v2018.03-189-gda773532cd)

This adds xxd as a build-time requirement. Not sure whether that needs mentioning in the Kconfig help text. On my Ubuntu 16.04, it is provided by the vim-common package, while more recent Ubuntu and Debian seem to have split it to a separate package.

 Makefile              | 16 ++++++++++++++++
 env/Kconfig           | 18 ++++++++++++++++++
 include/env_default.h |  4 ++++
 3 files changed, 38 insertions(+)

Makefile +16 -2

index 5fa14789d9..867b189c41 100644
@@ -423,6 +423,7 @@ endif
 
 version_h := include/generated/version_autogenerated.h
 timestamp_h := include/generated/timestamp_autogenerated.h
+defaultenv_h := include/generated/defaultenv_autogenerated.h
 
 no-dot-config-targets := clean clobber mrproper distclean \
 			 help %docs check% coccicheck \

@@ -1387,6 +1388,10 @@ ifeq ($(wildcard $(LDSCRIPT)),)
 	@/bin/false
 endif
 
+ifeq ($(CONFIG_USE_DEFAULT_ENV_FILE),y)
+prepare1: $(defaultenv_h)
+endif
+
 archprepare: prepare1 scripts_basic
 
 prepare0: archprepare FORCE

@@ -1434,12 +1439,23 @@ define filechk_timestamp.h
 	fi)
 endef
 
+define filechk_defaultenv.h
+	(grep -v '^#' | \
+	 grep -v '^$$' | \
+	 tr '\n' '\0' | \
+	 sed -e 's/\\\x0/\n/' | \
+	 xxd -i ; echo ", 0x00" ; )
+endef
+
 $(version_h): include/config/uboot.release FORCE
 	$(call filechk,version.h)
 
 $(timestamp_h): $(srctree)/Makefile FORCE
 	$(call filechk,timestamp.h)
 
+$(defaultenv_h): $(CONFIG_DEFAULT_ENV_FILE:"%"=%) FORCE
+	$(call filechk,defaultenv.h)
+
 #
---------------------------------------------------------------------------
 quiet_cmd_cpp_lds = LDS     $@ cmd_cpp_lds = $(CPP)
-Wp,-MD,$(depfile) $(cpp_flags) $(LDPPFLAGS) \ diff --git

a/env/Kconfig b/env/Kconfig index a3c6298273..e8e21dcfc6 100644

env/Kconfig +4 -0

@@ -486,4 +486,22 @@ config ENV_SIZE
 
 endif
 
+config USE_DEFAULT_ENV_FILE
+	bool "Create default environment from file"
+	help
+	  Normally, the default environment is automatically

generated

env/Kconfig +14 -0

+	  based on the settings of various CONFIG_* options, as well
+	  as the CONFIG_EXTRA_ENV_SETTINGS. By selecting this option,
+	  you can instead define the entire default environment in an
+	  external file.
+
+config DEFAULT_ENV_FILE
+	string "Path to default environment file"
+	depends on USE_DEFAULT_ENV_FILE
+	help
+	  The path containing the default environment. The format is
+	  the same as accepted by the mkenvimage tool: lines
+	  containing key=value pairs, blank lines and lines beginning
+	  with # are ignored.
+
 endmenu

include/env_default.h +1 -0

index b574345af2..1fbeb92f38 100644
@@ -22,6 +22,7 @@ static char default_environment[] = {
 #else
 const uchar default_environment[] = {
 #endif
+#ifndef CONFIG_USE_DEFAULT_ENV_FILE
 #ifdef	CONFIG_ENV_CALLBACK_LIST_DEFAULT
 	ENV_CALLBACK_VAR "=" CONFIG_ENV_CALLBACK_LIST_DEFAULT "\0"
 #endif

Hi Rasmus,

Quoted 5 lines

Modifying the default environment via CONFIG_EXTRA_ENV_SETTINGS is somewhat inflexible, partly because the cpp language does not allow appending to an existing macro. This prevents reuse of "environment fragments" for different boards, which in turn makes maintaining that environment consistently tedious and error-prone.

It is also possible to build boot.scr image, which is afterwards read from e.g. vfat, from text file.

As a reference and example please look
into ./boards/samsung/common/bootscripts/*.cmd

Quoted 1 line

Quoted 3 lines

This implements a Kconfig option for allowing one to define the entire default environment in an external file, which can then, for example, be generated programmatically as part of a Yocto recipe,

Is this yocto generation upstreamed? Or this is some kind of internal patch?

The patch looks ok.

Reviewed-by Lukasz Majewski <[email protected]>

Quoted 7 lines · Lukasz Majewski

Hi Rasmus,

Quoted 5 lines

Modifying the default environment via CONFIG_EXTRA_ENV_SETTINGS is somewhat inflexible, partly because the cpp language does not allow appending to an existing macro. This prevents reuse of "environment fragments" for different boards, which in turn makes maintaining that environment consistently tedious and error-prone.

Quoted 4 lines

The patch looks ok.

Reviewed-by Lukasz Majewski <[email protected]>

Modifying the default environment via CONFIG_EXTRA_ENV_SETTINGS is somewhat inflexible, partly because the cpp language does not allow appending to an existing macro. This prevents reuse of "environment fragments" for different boards, which in turn makes maintaining that environment consistently tedious and error-prone.

This implements a Kconfig option for allowing one to define the entire default environment in an external file, which can then, for example, be generated programmatically as part of a Yocto recipe, or simply be kept in version control separately from the U-boot repository.

Tested-by Sean Nyekjaer <[email protected]>

Signed-off-by Rasmus Villemoes <[email protected]>

Reviewed-by Lukasz Majewski <[email protected]>