From 2547049a5ab685e3f67dc81e58365cc55205fe1a Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Thu, 30 Jun 2011 18:56:53 -0700
Subject: Add CONFIG_DELAY_ENVIRONMENT to delay environment loading

This option delays loading of the environment until later, so that only the
default environment will be available to U-Boot.

BUG=chromium-os:17055
TEST=build U-Boot with option enabled, see that environment is not available

Change-Id: I99a25b468fb5d14310b00eb3fd4c3e6a0c5cbe2b
Reviewed-on: http://gerrit.chromium.org/gerrit/3534
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
---
 README               | 6 ++++++
 arch/arm/lib/board.c | 4 ++++
 common/env_common.c  | 5 +++++
 include/common.h     | 3 +++
 4 files changed, 18 insertions(+)

diff --git a/README b/README
index 8f91d8cc620..501a52d5586 100644
--- a/README
+++ b/README
@@ -2537,6 +2537,12 @@ Configuration Settings:
 	cases. This setting can be used to tune behaviour; see
 	lib/hashtable.c for details.
 
+- CONFIG_DELAY_ENVIRONMENT
+		Normally the environment is loaded when the board is
+		intialized so that it is available to U-Boot. This inhibits
+		that so that the environment is not available until
+		explicitly loaded later by U-Boot code.
+
 The following definitions that deal with the placement and management
 of environment data (variable area); in general, we support the
 following configurations:
diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c
index c3dcbba1ee9..a043648b261 100644
--- a/arch/arm/lib/board.c
+++ b/arch/arm/lib/board.c
@@ -569,8 +569,12 @@ void board_init_r (gd_t *id, ulong dest_addr)
 	dataflash_print_info();
 #endif
 
+#ifdef CONFIG_DELAY_ENVIRONMENT
+	env_set_default();
+#else
 	/* initialize environment */
 	env_relocate ();
+#endif
 
 #if defined(CONFIG_CMD_PCI) || defined(CONFIG_PCI)
 	arm_pci_init();
diff --git a/common/env_common.c b/common/env_common.c
index c3e6388ac0b..745cd51b38e 100644
--- a/common/env_common.c
+++ b/common/env_common.c
@@ -246,6 +246,11 @@ void env_relocate (void)
 	}
 }
 
+void env_set_default(void)
+{
+	set_default_env(NULL);
+}
+
 #ifdef CONFIG_AUTO_COMPLETE
 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
 {
diff --git a/include/common.h b/include/common.h
index c037b361915..4fb8315d129 100644
--- a/include/common.h
+++ b/include/common.h
@@ -287,6 +287,9 @@ int	saveenv	     (void);
 int inline setenv   (char *, char *);
 #else
 int	setenv	     (char *, char *);
+
+/* Set environment to the default value */
+void env_set_default(void);
 #endif /* CONFIG_PPC */
 #ifdef CONFIG_ARM
 # include <asm/mach-types.h>
-- 
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