Linux 7k-HOWTO

Linux 7k-HOWTO The Linux-7110 Project, 8th Septmber 2000 This document contains brief instructions on how to get a Psion 5 or Geofox One to boot into the Linux operating system Disclaimer

This is the method generally used for getting Linux running on the Psion 5 - it may not work for you, if it makes your Psion blow up and your house fall down for all I know. Don't blame anybody if something goes wrong. That said, if you have any problems you can always join the mailing list somebody there should be able to assist you.

Credits

This document was derived (stolen) from the original booting-howto written by Stephen Harris and additions by George Wright and loosely tied together by myself. The credits list is as follows;

Stephen Harris (swh@@ecs.sowton.ac.uk) George Wright (georsoc@@attglobal.net) Nathan Catlow (ncatlow@@users.sourceforge.net)

Please see the on the website for the more excellent people involved in the port. Obviously if you feel you have not been credited properly then please get in touch.

Introduction

The Linux7k project is an effort to port the widely used Linux operating system to the Psion Series 5 pocket computer .

So far the team has ported the Linux 2.2.1 Kernel to the Series 5 and Geofox One, created Arlo and created several initial ramdisks (initrd) for the project.

Psion Series 5 Specifications

Memory - 8 or 4MB Processor - CL-PS7110 ARM Processor 18MHz Display Resolution - 640x240 (Half-VGA) Display Type - Monochrome touch-screen (16 shades) Removable Media Type - Compact Flash® (CF) Disks Default OS - Epoc32 1.00 or 1.01

How does it work?

Bootloader - The bootloader, Arlo, does for Epoc what Loadlin does for Dos. It releases the memory from Epoc, places the kernel and initrd in the appropriate places in memory, and then boots the Linux kernel. Kernel - The kernel has patches applied to it, which makes it compile for ARM based systems, and also has a few more patches for the Psion Hardware. The kernel port to the Series 5 is basically finished now. Initrd - This is a virtual filing system image, which contains a miniture version of Linux. These can range in size but the more ram used for the ramdisk will leave less for the operating system. The kernel loads these images as the root partition.

Preparation

What you will need:

A backup of your Psion's disks (this is very important as everything in your C: drive will be fried. Your D: drive may escape, but don't count on it. The Psion installer The Arlo for you model of Psion (5 or 5mx) A glued kernel image A compressed initrd A paperclip or similar, thin, blunt item (to reboot your machine)

Booting using Arlo Copying files onto the Psion

The easiest way to get the files onto your Psion is to use Plp tools, compile and install these and use this to transfer the necessary files onto the Psion's ramdisk or CF through Epoc. For example to copy the arlo.sis file onto the Psion's C drive (ramdisk) you type the following command:

rfsv write arlo.sis c:/arlo.sis

Installing Arlo

You need to install Arlo (the boot loader - equivalent to LILO) onto your psion, to do this, extract arlo-0.51.tgz and copy the Arlo.sis file to your Psion, then copy the INSTEXE.EXE and run it. This should change the icon for Arlo.sis, which you can then run and it will install itself to either C: or D: as you select - it will work fine from either. Although, as far as I can tell you need to reinstall it each time you boot Linux.

Getting a kernel

You need a kernel for this project. I would recommend trying one of Werners precompiled ones. A good one to try is stable-221-cb23-519-psi.gz

Next uncompress the glued kernel image with

% gunzip <glued image name>

and copy the glued-* and initrd-*.gz files to C:\ on the Psion as image and initrd.gz.

Getting the kernel booted from EPOC Loading the kernel

At this stage you are ready to boot into Linux. Double check you have good backups of you Psion and then double-click Arlo.exe. You should see:

Loading logical device Opening the channel Commands are: ... Option buffer at address XXX Memory description at address YYY > _

Now type:

l image

you should see:

Opening file image Succeeded File size XXX Loading XXX bytes to address YYY Read XXX bytes No pages = ZZZ > _

Loading the initial ramdisk (initrd)

Now type:

l initrd.gz

you should see:

Opening file initrd.gz Succeeded File size XXX Loading XXX bytes to address YYY Read XXX bytes No pages = ZZZ > _

Passing additional parameters into the kernel

If you need to pass any other parameters into the kernel at this point (for example an alternative root filesystem) you need to type:

o root=/dev/hda2

A full description of kernel parameters can be found in /usr/src/linux/Documentation/kernel-parameters.txt.

Running the kernel

Now type:

Your Psion should now boot into Linux!

If it does a double bleep and then puts up the EPOC logo, something has gone wrong. Try reinstalling Arlo (from the Arlo.sis and INSTEXE.EXE files).

What can I do now?

Good question. I start by mounting /proc, its satisfying and actually useful.

Type:

mount -t proc /proc /proc

You can then ls /proc if you want, good, eh?

You can also mount CF discs with:

mount -t msdos /dev/hda1 /mnt

You will get some errors when you first mount the disc and long filenames will produce errors when they are ls'd.

If you are feeling brave you could

dmesg > /mnt/dmesg.txt

But you run a greater risk of trashing your CF disc.

Creating a filesystem on your compact flash

If you want to boot your system off a CF disk, you need to repartition it. You will need a reasonably sized CF, though (over 16Mb).

First, you boot into initrds3.gz, with a kernel that supports CF disks. When this has booted up, you need to execute fdisk /dev/hda. You can then repartition your system. ideally you should make a 4-6Mb Fat16 partition as /dev/hda1, and then assigning the rest for Linux (/dev/hda2). When you have done this, boot into Epoc and format the CF. Install Arlo, a kernel and an initrd in the root of this partition. Now you don't have to re-install Arlo every time you reboot.

To boot a CF based system, you need to pass the appropriate option into the kernel (see ), alternatively you will need to use the rdev command to alter the flags in your homebrew kernel before you glue it.

Autobooting Arlo from reset

To automatically boot into Arlo (or in fact any epoc program) you must create a '\system\data\wsini.ini' file on your CF FAT partition, it should contain the following line;

STARTUP d:\arlo.exe

This presumes you have the arlo executable on the d: drive (compact flash) and the associated Arlo .

How do I get back to EPOC?

(This applies to the Psion 5 - Geofox instructions forthcoming...)

Type:

sync sync sync

Close the machine (I don't think this does any good, but it makes me feel better).

On the Psion:

Open the battery backup door and locate the small copper coloured circle near the battery, using a partly unfolded paperclip or similar, gently press in the copper coloured circle. Now close the backup battery door, and, while holding down both shift keys press the Esc/on key. The machine should bleep once and then display the Psion 5 splash screen, after a delay you will be back in the EPOC system.

On the Geofox: (info supplied by Hennie Strydom)

It is mostly identical to the Series 5, with the single exception that the reset switch is next to the speaker on the bottom of the Geofox.

Rolling your own (Cross Compiling) Cross Compilation Environment

You will need a cross compilation environment if you want to compile your own kernels, or if you want to compile your own applications for the system. To set it up, you will need the xdev package which is provided at ftp.calcaria.net. Uncompress this file in the / directory of your desktop Linux system. You then need to set your PATH to include /scr atch/psion/xdev/bin. Check the xdev-0.README for full details.

Compiling a Kernel

Alternatively, you can create your own kernel, using the cross compilation environment described earlier. To compile a custom kernel, you will need to download the following files:

linux-2_2_1.tar.gz patch-2_2_1-rmk2.gz linux-2_2_2-philb-990208.gz crash+burn-26_patch.gz

Assuming that you have downloaded these and copied them to $HOME/Linux7k, execute the following commands:

cd $HOME/Linux7k gunzip linux-2_2_1.tar.gz tar -xvf linux-2_2_1.tar zcat patch-2_2_1-rmk2.gz | patch -p0 zcat linux-2_2_1-philb.gz | patch -p0 cd linux zcat ../crash+burn-26_patch.gz | patch -p1

These commands have now patched the Linux kernel for use with the Psion Series 5.

You must now configure and compile the kernel. To configure it, execute:

make xconfig

Or, if you don't have XWindows, execute:

make menuconfig

When you have done this, execute this command to make the kernel:

make Image

This command will create a kernel image in arch/arm/boot/Image.

'Glueing' the kernel

You must now "glue" the kernel, so that it can boot on the Psion. This basically adds the ARM 'bootstrap' code onto the front of the kernel. To do this, execute the following commands:

cd ../ gunzip boot-13.tar.gz tar -xvf boot-13.tar.gz cd boot make ./glue.pl ../linux/arch/arm/boot/Image > ../kernel_image

These commands will now make a glued kernel image in $HOME/Linux7k/kernel_image. You may now use this kernel image as your kernel.

Debugging GDB Stub

There is a GDB stub available from the sourceforge ftp site written by Noel Cragg, the README details all you need to know.

Armulator

To simulate the Psion 5 on your desktop with full debugging capability you can use the by Ben Williamson, cool bit of kit.

F.A.Q Q: Which Psion 5 model do I need (4 or 8Mb) It is best if you have an 8Mb model, also a Compact Flash card is essential if you want a useful system. Q: I have tried to load an initrd > 512k, but the boot process freezes at "Compressed image found at block zero" A: You are not using boot version 1.2 or higher, or... Q: When I try to load Klaasjan's initrds3.gz, I get a whole heap of numbers displayed on the screen (a kernel oops). A: This is a rare problem, as only two people have had this problem so far. To solve this, take the -DAUTODETECT option out of the Makefile in the boot subdirectory. Q: My Apacer CF card doesn't work A: This is a known problem, patched by Justin Davies (justin@@suse.co.uk), patch will soon be released. Q: What actual files are used by Arlo A: There are three files that make up the arlo installation, these are as follows;

\arlo.exe \System\Libs\lilo.ldd \System\Libs\tuiedit.ldd

Resources Websites

The following websites hold information about the linux-7110 project;

To be completed.....

Plp Tools

This is the easiest program to transfer files from you linux desktop to the psion, pretty much plug-n-play.

Epoc Program Installer (Instexe.exe)

Included in the Arlo-0.51 distribution.

Arlo For the Psion 5

For the Psion 5mx

Precompiled Kernels

Initial Ramdisks (initrd's)

Future Plans

These are some of the future plans for the project:

To port the X Windowing System (more likely a micro version such as nanoX) To port the 2.4 series kernels To create a distribution To provide support for the Series 5mx