__init open source patches

I have sent first set of patches to open source community.
http://groups.google.com/group/beagleboard/browse_thread/thread/8de18bd670af4b65
http://groups.google.com/group/beagleboard/browse_thread/thread/106229271065c60c
http://groups.google.com/group/beagleboard/browse_thread/thread/caf98e3843d97008
Thanks to Nishanth.

The real fun is to send patches for Linux-OMAP. First is to deal with u-boot-v2 !

Qemu and N800

At last decided to use QEMU since it has support for latest ARM processors. Now I can browse using lynx on ARM integrator !

Actually, I wanna have a simulated OMAP based board. Poky people have done amazing thing.
They have patch for QEMU to simulate Nokia N800 internet tablet(based on OMAP 2420 )
I tried latest release pinky 3.1( http://pokylinux.org/releases/pinky-3.1), but had trouble with build scripts with broken link wget 'http://downloads.sleepycat.com/db-4.2.52.tar.gz. damn it, it wasted so many hours earlier.
Anyways this time I am not goin to give up. I went ahead with checking out the latest Poky code.
ragha@hoysala:~$ svn co http://svn.o-hand.com/repos/poky/trunk poky
ragha@hoysala:~$ source poky-init-build-env
ragha@hoysala:~$ bitbake poky-image-sato
Again things are not easy.
problem1:This time it is new feature in kernel 2.6.2x. /proc/sys/vm/mmap_min_addr is set to non-zero as an additional security to avoid user applications mmap first couple of pages.
Ubuntu ships with 65536 as a default value for mmap_min_addr, which prevents qemu from mmapping the low address spaces it wants, thus breaking the qemu.
ragha@hoysala:~$ sudo sysctl -w vm.mmap_min_addr=0
problem2:Damn debian guys have changed sh link to dash instead of bash. I hate these political changes. They just don't understand how many scripts can break such change. anyways I have to move on:
ragha@hoysala:~$rm /bin/sh
ragha@hoysala:~$ln /bin/bash /bin/sh
I hate to wait since building Poky takes more than 4-5 hours even on Dual core !! I wonder why they are building the whole linux system.

Let me see if I can run N800 by tomorrow morning.

Writing a Simple File System

Neat guide
Writing a Simple File System

Using Quilt To Push Patches

create, apply, remove and for more check out the tool Quilt.
http://www.suse.de/~agruen/quilt.pdf
Linux: Using Quilt To Push Patches To -mm KernelTrap

QEMU vs SKYEYE

I have been looking for 'working from home' to spend couple of hours on 'WISHFUL' projects with the hardware boards. But being a (new)contractor is difficult to get VPN access . This constraint made me to think of emulators. Among many available, Skyeye and QEMU caught my eyes. Skyeye being a derivitive of ARMulator and legacy emulating tool for ARM. QEMU has many more new variants of ARM(upto Cortex and ARM MP core) being emulated. The question is which one is better? I am going to find out by trying both !

Wednsday I tried skyeye Hardy Heron, its awesome. I can successfully emulate many ARM based boards. Check this out for the ARM CPU and boards simulated by skyeye. http://skyeye.org/index.shtml
I am going to try writing some asssembly code for AT91 open hardware board.

This weekend I will be trying QEMU.

By the way I got some cool hardware to work at office. I need to catch up some time to do something with it.

Being 'screen'ed

I will briefly write about a wonderful tool which I have been enjoying since many years.
screen is a terminal multiplexer. screen as any other terminal application manages many terminals. But screen differers from other applications with its core features like:

• Remotely attach/detach to your same set of terminals running shells/processes from a different PC in network. (I love this!)
• Unlimited searchable scrollback buffer
• Quick switch between terminals
• Session sharing between users(Exciting)
• Easily turn on/off logging to file
• Save the content of scrollback buffer to a file

Screen has many more features which makes your life easier.
Before actually running screen, it's important to understand the default command character is Ctrl-A.
So start exploring it by running command screen and then for help press Ctrl-A + ? (control and ?)
[ragha@hoysala]screen
Also look for brief help by running screen -h

As you start using it you will get 'screened' (you will be concealed from danger !)

Nokia Morph Concept

Morph is a concept demonstrating some of the possibilities nanotechnologies might enable in future communication devices. Morph can sense its environment, is energy harvesting and self cleaning .
Morph is a flexible two-piece device that can adapt its shape to different use modes. Nanotechnology enables to have adaptive materials yet rigid forms on demand.

Find out more:
http://www.nokia.com/A4852062

Looks awesome. I want these technologies right now and Linux running on it!!