Embedded Linux and device driver development - linux

I plan to learn embedded linux and writing linux device drivers.
I need a dev board where I can,
Build and boot it with a linux distribution.
Write drivers for peripherals in the board.
(In future) Possible port Android to it
Can you suggest a dev kit to help me with this? Cost is not a bar - I am already familiar with linux at user space, I am willingly to spend to get better at the other side.
Thanks
James

How about a BeagleBoard (TI OMAP)? The Beagleboard has an active community and a lot of example projects, including an Android porting project. They're a few versions of Android behind the present day, but that should provide a starting point.

There is a new 25$ and 35$ option called Raspberry PI.

check this http://elinux.org/Android_on_OMAP
Google's Android on TI's ARM based OMAP SoCs / 2.6.23 Linux kernel

I think Armadeus project is for you. It is an open source project, that started in France and that is now expanding. The community is great and the number of peripherals is growing fast. Of course it is based on Linux.
A small company is building the boards. They are based on ARM9 and now ARM11. In the boards you also have a Xilinx FPGA, that open the doors for exciting experiments.
Hope this helps.
JCLL

Some cheap mini2440 linux board sounds like a good start. It can also run Android.

maybe you can have a Virtual Development Board, that is interesting.

Check also the OK6410 at http://www.arm9board.net, it is provided with Linux - 2.6.28 (2.6.36 in a quit near future) with all peripheral drivers and a basic Android system. You'll find it interesting and quit useful.

Related

How to start developing and debugging the Linux Kernel?

I want to start some Linux development for my research. Writing few simple scheduling algorithms and test them. I have few questions:
1) How do you develop for the linux kernel? IDE? How do you import the kernel files and see how they are related or connected?
2) Once you write your code, how do you simulate/debug it? I mean one can't just build the kernel for 20 - 30 minutes, make a new image and change boot.ini each time. This is a lenghty process plus you can't simulate or debug just observe if it works or not.
3) Is there A guide for starting developing in Linux. I find the lack of documentation surprising
I am developing for ARM-based boards
Excuse my ignorance.
Thanks
How do you develop for Linux kernel?
There are many components in the Linux kernel. Typically, kernel is divided into core and driver parts.
Core includes scheduling, MMU, memory management, process management etc
Drivers includes file system, networking, peripheral device drivers, USB etc
IDE is not a must to develop kernel code. For kernel veterans, VIM/nano is also OK. The development environment is up to you. If you are new to the kernel code, you want to build the function relationship views, some tools can be helpful:
Source Insight (Commercial)
vim + ctags (http://vim.wikia.com/wiki/Single_tags_file_for_a_source_tree)
How to debug it?
There are many Linux favors/distributions. You can use Software emulator or Hardware boards to debug the kernel. Android is based on Linux and there are many mobile phones or development boards that support Android. iOS is also derived from Linux and it is its own debug method.
Where to find the kernel documents?
For kernel part, there are many readme articles in kernel source tree. e.g. http://lxr.free-electrons.com/source/Documentation/debugging-via-ohci1394.txt
printk is powerful enough for newbies.
For ARM part, there are many articles in infocenter.arm.com
Debugging Linux kernels using DS-5
http://infocenter.arm.com/help/topic/com.arm.doc.den0024a/ch18s03s03.html?resultof=%22%6b%65%72%6e%65%6c%22%20

How can I program an ARM MCU using SWD under Linux?

I'm working with an STM32 ARM Cortex MCU. It supports a protocol called SWD (serial-wire debugging). Looking around on the web, I've found arm-none-eabi-gcc which seems to be a decent compiler, but on the hardware side I haven't really found a proper way to work with it.
I haven't been able to find an SWD programmer / debugger that is officially supported on Linux. The closest I've found was stlink which looks like a poorly maintained project. Can you please tell me what's the right way to go if I would like to work with this MCU and want to use Linux on my computer?
OpenOCD is supported, reliable and works just as well on Linux and Windows. I use it every day to program and debug the F0, F1 and F4 devices using SWD (not JTAG).
If you're an Eclipse user then the latest version of the GNU ARM Eclipse plugin will even automate the OpenOCD command line for you. I wrote a number of articles hoping to help new users on my blog.
Hardware-wise, if you're using the discovery boards then you have the requisite ST-Link support on board and don't need anything else. Otherwise there's the official ST-Link/v2 dongle and also some dodgy clones on a well known auction site.
Well, texane/stlink is a properly maintained project and I use it on daily basis. Segger J-Link supports Linux as well.
I have GCC ARM toolchain setup, with eclipse as my default IDE. I'm using both JLinks and STLinks for both JTAG and SWD interfaces.
I wrote few articles on my blog some time back, and I can post the links if you want to.

Benefits of UNIX or UNIX variant on microcontroller?

This may be a foolish question but I've been searching around for some time and don't see a clear answer. I've seen several microcontrollers advertised as running Unix-like software (Linux, Ubuntu) for example, the BeagleBone Black and Arduino Yun. Can someone please explain to me the benefit of this? So far I've used a couple of microcontrollers like the Arduino Uno/Duo, Freescale FRDM and STM32 Discovery which either didn't have this feature or I was not aware of it. I'm starting to see it more and more on newer microcontrollers so I'd like to know what it brings to the table.
Full disclosure: I've had minimal exposure to UNIX and its variants so far so please talk slowly and use small words =)
Hope to hear from you,
Yusif Nurizade
You get complex drivers already included Linux for free (USB, internet protocols, storage media and file systems).
You can use lots of free software for the things not included in the kernel.
It is simpler to develop software on a full OS (easier to debug, look what is going on, change the configuration, etc etc).
The drawback is that the real-time capabilities are generally worse than for some small RTOS, and it needs more resources (a couple of megabytes memory).
In the heart of all Android and iphone is a Embedded Linux System. Without getting too deep
Linux + Java = Android
BSD Unix variant + C/C++/Object C = iOS
Now if you get deeper the above two statement can be argued for accuracy
All Android devices run on ARM based microprocessors. Beaglebone is one such open source hardware platform with can run Android as well as Embedded Linux distribution and even a Ubuntu.
Now (IMHO) Ubuntu is primarily for desktop and server application. Many of the popular computer server farms uses Ubuntu.
Now STM32 is a ARM based CORTEX-M micro control. Once again (IMHO) is mostly used for bare metal embedded applications. I have hard that FreeRTOS can be ported to TM4C123 ARM Cortex-M TM4C123.
Now the advantages of using Linux base micro controller architecture are
OS is free for the most part
Larger community of users
The industry is moving towards open source
Lot of free resources get up to speed
Disadvantage are
Learning curve is pretty steep
Expect to stumble and fall a few time
Below to two good resources to learn Beaglebone open source development
Beaglebone
Introduction to Beaglebone development by Derek Molloy of Dublin City University
HTH and good luck

Getting started with this ARM7 board

This bad boy arrived in the post recently. But, didn't have any instructions, CD-ROM or Dev Kit stuff.
Despite lack of instructions, I'm pretty sure we should be able to get it going with DS-5, a JTAG cable and embedded linux. The goal is to get a small web server/site running on it.
It's an UB4020EVB board with SEP 4020 ARM7 chip. Has JTAG, USB and ethernet connections.
Does anyone know a) What hardware kit I need to get it up and running with an OS, and b) if there's any particular JTAG cable we need.
Any help appreciated.
Thanks!
T
Good luck; all the data I can find on this is in Chinese. Apart from that ARM7 is not a good platform for Linux since it lacks an MMU. uCLinux will run without an MMU, but rather misses much of the benefit of using Linux in the first instance.

Paravirtualizing linux on an ARM platform

I want to learn how to port linux to an ARM platform, and I am wondering if you guys have any tips or resources on how to do that? Everything from writing the boot file to setting up the interrupt vector, writing the linker script and having the executable system running.
I was thinking of buying a developer board to learn this, maybe Beagle board as it uses an ARM cortex processor and has a big user community. Is this a good idea? I am not very familiar with linux or porting operating systems in general, so any tips on how to get started would be nice!
What I want to do in the end is to virtualize all the linux kernels privileged operations to run in a hypervisor. Currently I have a hypervisor that is run beneath freeRTOS. All freeRTOS privileged operations (very few operations) have been changed to trap into the hypervisor by generating a SWI interrupt which leads to the hypervisor. What I want to do is too extend it to Linux instead which is more complex and alot bigger.
Best regards
Mr Gigu
You might want to check out the way it's done in L4Linux.
I would say start here...
http://elinux.org/BeagleBoard
From what I have seen, the Beagle Board seems to be one of the most widely supported boards 'community-wise' at this level.
As far as your questions goes, I am not totally sure what it is. If you are diving into all this embedded OS and linux stuff and want to have fun, that board is the probably way to go if you have some background with embedded development (which it seems you do). As far as professional development, not so sure...

Resources