Jornada 820 bootimage information
$Id: README,v 1.6 2005/07/25 12:18:01 fare Exp $
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BUILD ENVIRONMENT
The Makefile ought to contain everything you need to build the bootimage.
For hacking, an optional script "please" helps you do things
with the kernel tree.
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make toolchain
create a toolchain to compile the bootimage.
All other targets assume that a toolchain is present.
The toolchain is based on uClibc - http://www.uclibc.org/
You may make it available in your PATH with
ln -s ${TOPDIR}/uclibc/buildroot/build_arm/bin/arm-linux-uclibc-* /usr/local/bin/
or
PATH=${TOPDIR}/uclibc/buildroot/build_arm/bin:$PATH
Alternatively, you may reuse a toolchain that you already possess.
You may notably find glibc-based toolchains on
http://www.handhelds.org/z/wiki/Toolchains
http://www.opensistemas.com/Gentoo_for_Zaurus.715.0.html
http://www.openzaurus.org/official/toolchain/
But mind that glibc is both more bloated and less featureful
(the resolver doesn't work with static binaries).
Also note that you can put your toolchain to good use with distcc and ccache,
so as to speed up compilation on your Jornada.
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make j820
create a bootimage based on the Linux 2.4 kernel.
Assumes that you have a working toolchain.
The Linux 2.4 kernel is rather stable and is usable as the basis for hacking.
It has been successfully used as an XEmacs-based editing machine
and as a debian-arm host.
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make j820-26
create a bootimage based on the Linux 2.6 kernel.
Assumes that you have a working toolchain.
Note that the 2.6 kernel might not be usable right now.
Most importantly, it lacks pcmcia support as of the writing of this line.
See the TODO file.
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BUILD ENVIRONMENT NOTES
Although it's been used a lot, the current build system may still have
glitches, caused by thinkoes and bitrot. We apologize for the inconvenience.
Please report to us any bugs as you experience them.
We will try to automate things and make the build process
as seamless as affordable.
Typical kinds of bugs:
Sometimes, a target won't work at first, because some file didn't exist.
Sometimes, a target will do too much work at second,
rebuilding stuff that's already there.
Sometimes, a target will fail in a subtle way because old files got in the way;
the solution is to remove the cruft.
rm -rf linux/upstream/*/ linux/build
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RAMDISKIMAGE USAGE
The ramdisk that is built by this Makefile has the following usage:
* lots of functions are defined in /etc/functions -- see by yourself
* you may add your own additional functions in /etc/functions.local
* Use "standalone" to configure linux for standalone usage with the ramdisk.
* Use "rootfs" to chain-boot into your first Linux partition on CF.
* The ramdisk will automatically attempt to "rootfs" at startup, unless you
create a file or directory named "noautomount" in your WinCE partition.
* We have mkfs.minix and fsck.minix in busybox. No ext2 support, sorry.
To build an ext2 filesystem, you'll have to use a CF reader on your PC,
or to NFS mount a filesystem with your ext2 utilities.
* Busybox is packed up with lots of functionality. Check it out!
* To free the memory occupied by the ramdisk, your rootfs will need to run
the program blockdev, which is part of the util-linux debian package.
* With kernel 2.6, you must use cat /proc/modules instead of lsmod
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RAMDISKIMAGE NOTES
* We now build with a uclibc toolchain.
Building with a glibc toolchain will not only make everything much larger, it
will also break the resolver functionality, that requires dynamic loading (!)
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KEYBOARD NOTES
* The top row keys are mapped to F1..F10, SysRq, Suspend.
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USERLAND NOTES
* You can make your own debian userland with the included mkxdeb script.
* if cardmgr oopses after pivoting to rootfs, it might very well be because
of invalid I/O specifications in /etc/pcmcia/config.opts -- the file has
statements such "include port 0x100-0x420" that tells the kernel to scan a
range of ports, which might make sense on an old PC, but which is badly
broken on the Jornada 820.
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PERIPHERAL SUPPORT
* the pcmcia slot is a 16-bit PC-Card, and doesn't support 32-bit CardBus.
Don't be surprised if CardBus cards do not work.
* NE2000-compatible (pcnet_cs) ethernet 10BaseT network cards
and Hermes-chipset (orinoco_cs) 802.11b wireless cards are reported to work.
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