diff --git a/README.u2 b/README.u2 index d66ade316..26138e60c 100644 --- a/README.u2 +++ b/README.u2 @@ -44,14 +44,6 @@ finished (you can simulate this by using the standard demo config file with 'make linux_defconfig'), there is a .config file in the toplevel directory of the sourcode. -U-Boot usually needs an environment, storing the configuation data, plus -a filesystem space for scripts etc. You can create one locally with - - # dd if=/dev/zero of=env.bin bs=1024 count=128 - # FIXME - what to do to get a solid environemt - # mkcramfs somedir/ cramfs.bin - # FIXME - create filesystem - Once U-Boot is configured, we can start the compilation # make @@ -61,8 +53,17 @@ If everything goes well, the result is a file called uboot: # ls -l uboot -rwxr-xr-x 1 rsc ptx 114073 Jun 26 22:34 uboot -This U-Boot image is a normal Linux executable, so it can be started -just like evary other program: +U-Boot usually needs an environment for storing the configuation data. +You can generate an environment using the example environment contained +in examples/environment: + + # ./scripts/ubootenv -s examples/environment/ env.bin + +To get some files to play with you can generate a cramfs image: + # mkcramfs somedir/ cramfs.bin + +The U-Boot image is a normal Linux executable, so it can be started +just like every other program: # ./uboot -e env.bin -i cramfs.bin @@ -71,6 +72,16 @@ just like evary other program: loading environment from /dev/env0 uboot> / +Specifying -[ie] tells U-Boot to map the file as a device +under /dev. Files given with '-e' will appear as /dev/env[n]. Files +given with '-i' will appear as /dev/fd[n]. +If U-Boot finds a valid configuration sector on /dev/env0 it will +load it to /env. It then executes /env/init if it exists. If you have +loaded the example environment U-Boot will show you a menu asking for +your settings. + + + FIXME: cfi currently doesn't work with um-uboot @@ -91,7 +102,7 @@ edit -> ctrl-c ctrl-d md -f /dev/nor0.1 exec /env/init FIXME: doesn't work yet saveenv (makes /env persistent) -> /dev/env0 -printenv (FIXME: obsolete) +printenv mount Shell