Translation(s): none

(!) ?/Discussion

DebianOn is an effort to document how to install, configure and use Debian on some specific hardware. Therefore potential buyers would know if that hardware is supported and owner would know how get the best out of that hardware.

The purpose is not to duplicate the Debian Official Documentation, but to document how to install Debian on some specific hardware.

Models covered
PC-Z1 ?NetWalker

Sub-models :
- Video card
- Screen size: 5" WSVGA (1024x600) with touchscreen
- Internal wireless card

Overall Status

Here is overall status of Debian on Sharp PC-Z1 (NetWalker).
Not official (2.6.31 kernel port) for Sharp ?NetWalker PC-Z1.

System as sold

This comes with GNU/Linux pre-installed.

Debian on microSD

So far, it seems to be able to install Debian by using the recovery microSD card. (NetWalker PC-Z1 Debian : This link is to Japanese page)  This requires you to boot system as recovery mode and root is on microSD card.

Debian on MTD

In order to install to on board mtd flash, ubi.img needs to be created and placed onto the recovery microSD card.

Resource for hacking

Here are some resources to use Sharp PC-Z1 (NetWalker) by both Debian and Ubuntu.

For English users: How to change Sharp NetWalker PC-Z1 OS into English.

Compatible hardware

Kernel and user land source as provided

{i} Sharp official GPL compliance site: not working as of Oct 25, 2009. This is sad ...

{i} Kernel source: http://netbook-remix.archive.canonical.com/updates/pool/public/l/linux-fsl-imx51/

This source has few interesting lines in "grep -R spider *":

<!> The armel architecture is known to use "char" as "unsigned" which is not normal behavior thus breaks many existing softwares working fine on i386.

Ubuntu kernel provided is patched. You need to use it for now to get proper hardware supports. Many user land softwares are patched for armel too.

APT line can be added to get sources for kernel and other applications:

deb-src http://ports.ubuntu.com/ubuntu-ports jaunty main universe
deb-src http://netbook-remix.archive.canonical.com/updates/dists/jaunty-araneo/ jaunty main universe

URL links for browsers:

/!\ Although it is tempting to put archive such as Ubuntu security updates for Ubuntu system as provided, it will likely to break installed softwares such as Firefox. I guess update from pertinent canonical archive is needed for proper armel patched updates.

{i} Kernel cross compile hint: NetWalker Kernel Rebuild (JPN)

UFO

UFO: unidentified foreign object :-)

There are 3 UFO packages which are not found on the repository.

On rescue microSD, there are 8 UFO binaries (flash_erase, flash_eraseall, nanddump, nandverify, nandwrite, ubiattach, ubidetach, ubiformat)

These should have beem installed as a part of initial installer image. (most of these programs are available in the debian package:mtd-utils http://packages.debian.org/mtd-utils )

<!> Directories related to the imx-lib package are set to UID=1000 (first login user). Also / being 777 permission is a bad bug. These can be used to escalate privilege thus considered security bug. (I know risk is small but this is sloppy.)

Recover script

The official recover script will let you create microSD (2GB). That is essentially:

Alternative recovery script

In order to enable our normal Debian PC with good network connection to create recovery disk, I created alternative recovery script: spider-recovery

<!> This may be buggy. Please use this with care after reading its source.

Recommended use style:

Last resort use style:

Please note (tune2fs -l):

The original ext3 hash algorithms assumed that variables of type char were signed, as God and K&R intended. Unfortunately, this assumption is not true on some architectures. There were patch to fix kernel (2009-05-08 11:58:01). The armel architecture is known to use "char" as "unsigned". Debian lenny can handle signed_directory_hash and unsigned_directory_hash. Somehow tools on recovery image treats non-armel formatted disk as non-clean. As a work around, symlink at /etc/rcS.d/S30checkfs.sh on such microSD card is killed in my recovery disk if created by non-armel.

Bootloader

This seems to use Redboot as its backend.

Per, comments in update_spider.sh:

#   spider.srp
#    6,rootfs.jffs2   (RFS jffs2)
#    5,ubi.img        (RFS ubifs)
#    4,zImage         (Kernel)
#    3,info.bin       (System information)
#    2,fis.bin        (Redboot fis)
#    1,redboot.bin    (Redboot)

Normally, it is wise not to touch NOR flash since it will make your system unbootable. If you break it, you need hardware such as JTAG connected to somewhere on main board to fix your system.

Rescue microSD only update ubi.img and zImage to reinstall system. Related links:

Internal hardware

Official hardware spec is at http://www.sharp.co.jp/netwalker/spec/index.html

You can see internal hardware photos at http://hitaki.net/diary/20090928.html. Per this page:

Here, you can see keyboard: http://blog.livedoor.jp/j02r/archives/1084872.html