[U-Boot] u-boot on raspberry pi with fw_printenv/fw_setenv

[Waldemar Brodkorb <wbx@openadk.org>]

Hi,
B.R. Oake wrote,

> On 06/01/15 12:08, Waldemar Brodkorb wrote:
> > I am looking for a way to change u-boot environment from Linux
> > on a Raspberry PI. I have fw_printenv/fw_setenv, but I have no clue
> > how the config file looks like, when using uboot.env as a file on
> > the first vfat partition. I am not sure, but it looks like there
> > is no code to use fw_printenv/fw_setenv with files.
> 
> Hi Waldemar,
> 
> fw_printenv and fw_setenv can act on an ordinary file instead of a
> device if you want; their config file is normally /etc/fw_env.config .
> So for example, first you could create an empty 16K file uboot.env:
> 
> dd if=/dev/zero of=uboot.env bs=1K count=16
> 
> then you could configure fw_printenv and fw_setenv to act upon that
> file by putting the following line in /etc/fw_env.config:
> 
> uboot.env 0x0000 0x4000 0x4000
> 
> I hope that helps,

Thanks a lot! This helps. Maybe an additional example in
fw_env.config would avoid another question about this in the future
;)

BTW: I needed a small path to let fw_printenv compiled:
---
u-boot-d8bec60c1b0de7770f9b56ad092ab9be801d99af.orig/tools/env/fw_env.h
2015-01-06 09:00:23.000000000 +0100
+++
u-boot-d8bec60c1b0de7770f9b56ad092ab9be801d99af/tools/env/fw_env.h
2015-01-07 13:13:44.399072426 +0100
@@ -14,6 +14,8 @@
 #include <config.h>
 #endif
 
+#include <generated/autoconf.h>
+
 /*
  * To build the utility with the static configuration
  * comment out the next line.

Otherwise compile breaks:
  HOSTCC  tools/env/fw_env.o
In file included from tools/env/fw_env.c:117:0:
include/env_default.h:110:11: error: expected '}' before
'CONFIG_SYS_ARCH'
  "arch="  CONFIG_SYS_ARCH   "\0"
           ^
make[4]: *** [tools/env/fw_env.o] Error 1


best regards
 Waldemar