Watapon ROM (Zaurus SL-5600)

[Chaos]

If anyone lurking out there has a Sharp Zaurus SL-5600, I thought I'd add a note about my custom ROM, Watapon.

After releasing 1.6 just-over-a-week-ago, I've added a bugfix updated tonight, 1.6.1. It simply adds a needed library for the mail program that I forgot (oops!). So now, it should be 100% bug free. And if there is a bug, I swear it's a feature.

So if you happen to have a SL-5600 Zaurus, go try it out. And if you don't, go "Ooh" and "Aah" at the pretty screenshots.

[TadW]

Nice work, Chaos. I didn't know you could that easily (was it easy?) make your own ROMs for Linux PDAs. Somehow I doubt this would be ever possible with Palm-based PDAs, even when Linux comes to Cobalt.

[Bob Russell]

Very interesting Chaos!

I'm curious, also, about what it took to do this, and how much skill was needed on your part. I guess I don't really even know what it entails or how you go about doing something like that. Is it just getting a distribution into the Zaurus Rom? Did you have to tweak drivers? Recompile and recombine code? I'd love to hear more...

Makes me think about getting a Zaurus, too. I probably won't because I'm cheap, probably wouldn't use it, and don't really have the time. And I'm trying to stay in the "mainstream" to keep things simple also. But... you make it very, very tempting!

[Chaos]

I'll outline the basic process I used...

First, grab a copy of the rootfs for the 5600. They were available on Sharp's developer site, but those disappeared a while back. I have a mirrored copy here: http://zaurus.duelmonsters.ca/files.

Starting with that rootfs, I proceeded to rip the original rootfs from my zaurus, excluding /home, /dev, and /var, IIRC (because of the way the Z works, those are stored differently from a normal Linux distro). I can't remember if I had to exclude /proc or if it was already excluded.

After that, I set everything up by untarring the base rootfs (the one I have mirrored), and then untarred the default 1.32 ROM rootfs which I ripped off my 5600. I then had something I could built from there to create a ROM identical to the 1.32 ROM. But I didn't. I proceeded to modify it.

I took out the /root/.home_default.tar file and untarred it to modify it, as that's what gets placed in the home partition when you format it.

Before going any further, I'll explain a basic of the Z's root filesystem. Everything outside of /home is read only. Only files within /home are read-write. So everything that need to be read/write, is stored within /home, with symlinks pointing into it. Symlinks are used a GREAT DEAL in a Zaurus ROM.

From that basic root filesystem, I proceeded to modify it however I chose, including (since last August when I started the project) replacing the default (crappy) PIM with KDEPIM/Pi (a suite of ported KDE PIM apps), zipping up the .home_default.tar, .dev_default.tar, and .var_default.tar files to save space, adding and removing programs, compressing some other large files (like the startup screen, which also got replaced), and many other minor changes.

In addition to simply adding programs, I did a small bit of code hacking to provide the version number functionality pictured here. The bottom third of that screen was modified to read the version number from /etc/watapon_ver. It wasn't that hard, but it was my first work with Z coding ever. Also of note, that's not the default sysinfo application, it's a modified OPIE one. In addition to that small hack, I modified an IRC application, called NeIC, to provide minimal support for other prefixes, such as the little-used ~ or &, since not supporting those caused problems. It simply displays them as normal ops, the way I changed it.

From there, it just requires me to zip up the home directory, and run ./bin/build.sh to build the initrd.bin image.

In addition to that, I also recompiled the kernel, removing a workaround for the PXA250 cache bug (the PXA250 is found in some 5600s, the PXA255 is in others), which effectively reduced the performance by 50%. Disabling it gives a great boost in speed, with a little danger to the stability. The stability danger isn't much of a concern though.

Other than that, I packed up a few applications to conform to the modified tab structure in the ROM. This was done with a couple shell scripts.


So, it may sound like a fair bit of work, but it's pretty fun.

If you want to read some more on this ROM, there's a thread over at the OE Forums, here.

[Bob Russell]

Thanks Chaos! While I can only understand this at a surface level, it's really awesome. I looked at some of the Sharp Zaurus 5600s on ebay longingly. But I figure it makes more sense for me to set up an old desktop that I have first.

Next time I get a good chunk of time to play, I'll get a KVM switch and give that a go. Thanks to you and Hacker, my Linux interest is rekindled again! If I really do get around to it, I'll ask you guys for a distro suggestion. Plus the linux.org site is pretty exciting when you see that long list of apps. It would be beneficial for me to learn something about Linux for work also, so I may just have to see if I can arrange for web training or an intro class!

Are you planning anything for the SL-C3000?... that looks pretty awesome also! Kind of like those OQOs and other handtop pcs, except at a much lower price because they "only" have to run Linux.

It's amazing what you've accomplished. I wonder why (except for the cache stability thing) Sharp didn't so something like this themselves. Is there a limitation that would prevent them, maybe due to licensing? Hope it's public enough that the Zaurus design team knows about it!

[Chaos]

Originally Posted by BobR

Thanks Chaos! While I can only understand this at a surface level, it's really awesome. I looked at some of the Sharp Zaurus 5600s on ebay longingly. But I figure it makes more sense for me to set up an old desktop that I have first.

That's where I started. An old 350 Mhz AMD K6-2 with 64 megs of RAM, running Mandrake Linux 7.1. KDE1, Linux kernel 2.2... Old stuff. That was almost six years ago now.

Originally Posted by BobR

Next time I get a good chunk of time to play, I'll get a KVM switch and give that a go. Thanks to you and Hacker, my Linux interest is rekindled again! If I really do get around to it, I'll ask you guys for a distro suggestion. Plus the linux.org site is pretty exciting when you see that long list of apps. It would be beneficial for me to learn something about Linux for work also, so I may just have to see if I can arrange for web training or an intro class!

There are SO MANY applications for Linux. Just take Debian for example. Among the libraries, programs, and every other Debian package... There are almost 10000 in the unstable branch.

Originally Posted by BobR

Are you planning anything for the SL-C3000?... that looks pretty awesome also! Kind of like those OQOs and other handtop pcs, except at a much lower price because they "only" have to run Linux.

If I had any other Zaurus, I'd probably make a ROM for it too. And if I had the money, I'd probably have another Zaurus. But I don't, so it'd be hard to do (no ability to test by oneself). The clamshell models also are able to run full X11. There's a project, mainly for the C700/750/760/860s (but will run on C3000/C1000 eventually - or already does - I haven't looked lately...), called pdaXrom. And if you don't know about the C1000, it's a version of the C3000, without the 4GB microdrive, but with 128 MB of internal flash total. It also has different colours, supposedly a black colour-scheme. It's basically meant to replace the now not-manufactured C860.

Originally Posted by BobR

It's amazing what you've accomplished. I wonder why (except for the cache stability thing) Sharp didn't so something like this themselves. Is there a limitation that would prevent them, maybe due to licensing? Hope it's public enough that the Zaurus design team knows about it!

The default ROM, while ok, is a bit plain. It's ok for "normal" users, but many people don't want something that's "ok". They're also limited by the space, by trying to include too much, in my opinion. They put in large apps like the Hancom word processor/spreadsheet, and the space-wasting games. I removed both, just getting rid of the games, and packing the Hancom apps as packages that can be installed.

I don't really think that Sharp has much interest in the "normal user" unfortunately. The Zaurus community has found this from the early days of the 5500. It was especially evident last year, when they stopped sell Zauri outside of Japan (many people now import the new ones), and shut down the Zaurus dev site, and community site. While the Zauri hardware is quite nice, Sharp hasn't really been that great at supporting the devices. They're a bit better in Japan, but still don't show much interest in the "average" consumer.

[SubNuke]

Originally Posted by Chaos

If anyone lurking out there has a Sharp Zaurus SL-5600, I thought I'd add a note about my custom ROM, Watapon.

That would be me.

Originally Posted by Chaos

So if you happen to have a SL-5600 Zaurus, go try it out.

I stumbled upon your Watapon package after figuring out the PXA255-specific OZ 3.5.3 package I had just installed did not include support for the TE-CF100 or WL1100C-CF cards I have.

Nice! I now have my most-used applications, Kx/Pi, Hancom Sheet, Opera, and OTR Player, all coexisting peacefully and operating along with wired and wireless ethernet without a hiccup!

Thank you very much!