summaryrefslogtreecommitdiffstats
path: root/tools/env/README
diff options
context:
space:
mode:
Diffstat (limited to 'tools/env/README')
-rw-r--r--tools/env/README29
1 files changed, 29 insertions, 0 deletions
diff --git a/tools/env/README b/tools/env/README
new file mode 100644
index 0000000..2b54adf
--- /dev/null
+++ b/tools/env/README
@@ -0,0 +1,29 @@
+
+This is a demo implementation of a Linux command line tool to access
+the U-Boot's environment variables.
+
+Configuration is done via #defines in the fw_env.h file. The
+following lines are relevant:
+
+#define HAVE_REDUND /* For systems with 2 env sectors */
+#define DEVICE1_NAME "/dev/mtd1"
+#define DEVICE2_NAME "/dev/mtd2"
+#define ENV1_SIZE 0x4000
+#define DEVICE1_ESIZE 0x4000
+#define ENV2_SIZE 0x4000
+#define DEVICE2_ESIZE 0x4000
+
+Current configuration matches the environment layout of the TRAB
+board.
+
+Un-define HAVE_REDUND, if you want to use the utlities on a system
+that does not have support for redundant environment enabled. The
+DEVICEx_NAME constants define which MTD character device(s) is (are)
+to be used to access the environment. If HAVE_REDUND is undefined,
+DEVICE2_NAME is ignored, as is ENV2_SIZE and DEVICE2_ESIZE. ENVx_SIZE
+defines the size in bytes taken by the environment, which may be less
+then flash sector size, if the environment takes less then 1 sector.
+DEVICEx_ESIZE defines the size of the first sector in the flash
+partition where the environment resides. It is assumed that the
+environment is located in the first ENVx_SIZE bytes of the device
+DEVICEx_NAME.