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.
Related
I am new to linux programming & interested to tweak linux kernel(though I am not sure, what to tweak, I am planning to write drivers for particular device). To learn internal of kernel, I have started from historic kernel release (first release).
My problem is, how to test whatever changes I am doing for development, without disturbing my current os environment.(ubuntu 12, 64 bit). Is there any way like virtual box, sandbox?
Along with these, if anybody send some good approaches to learn these things, I would be really greatful.
Thank You.
If you're new to linux programming then you really don't want to be tweaking the kernel. You really want to be an advanced programmer capable of programming drivers and complex software first.
But yes there is, you can can create a virtual machine using openbox or vmware. If you're really keen on tweaking the kernel you probably want to first just try compiling and configuring the kernel and seeing if that works.
Also make sure you're well acquainted with how the kernel works and advanced OS designs in general.
Search in google fr "Kernel configuration" you u will get many links how to configure your own kernel.
And one more thing do not use a outdated version of kernel ,always use latest stable release , because a lot of code and API is changed in new versions and no book in market is updated so ,, u have to read from kernel documentation. Thats the best way to learn the most updated information about linux kernel
Yes, you can test your changes on any of the commonly available virtual machines (VMs); that way, whatever changes you make to the VM kernel won't affect native OS.
Personally, I prefer using CentOS 64 bit on VMWare Player. With this setup, I got away with minimal system maintenance while was able to focus on the actual job at hand. Once the VM is up & running, you can download and compile one of the latest stable releases from kernel.org. Instructions on compiling your downloaded version of kernel could be found here and here; however, this may require little tweaking based on your actual setup. Once the VM is running on your desired version of kernel, using a combination of cscope and ctags will help you immensely in kernel code browsing.
Finally, if you want to become a serious kernel programmer and write your own device drivers, you need to get familiar with it in the first place. Below are a few excellent references -
Linux Device Driver by Corbet, Rubini, Kroah-Hartman, 3rd edition
Linux Kernel Development by Robert Love, 3rd edition
Understanding the Linux Kernel by Bovet, Cesati
Linux kernel source (ideally placed into your /usr/src/$(DESIRED_KERNEL) path, symlinked to /usr/src/linux)
Going through these books is a tedious job and chances are that you may hit the roadblock from time to time. kernelnewbies mailing list and StackOverflow are some of the few reliable places where people would be happy to answer to your queries.
Good luck!
I wanted to validate/test/benchmark set of features I have added to the ext4 kernel_tree/fs.
I came across Spruce Linux file system driver verification. Especially for filesystem.
The project is hosted #https://code.google.com/p/spruce/wiki/GettingStarted.
and this is for x86.
I work on arm target, and I have few questions before starting off.
Has anybody worked on Spruce earlier.
how to use Spruce project for ARM, Do we need to port for ARM?
Is cross compilation straight forward or any changes need to be done.
I have gone through this paper: http://syrcose.ispras.ru/2012/files/submissions/25_syrcose2012_submission_21.pdf
there is no information on ARM and its support.
Please someone explain/help who has any work experience/knowledge on Spruce project.
Spruce was intended to work as follows. It provides a set of tests that make the kernel module for a given file system execute as many paths in the code as possible. It allows to use some external analyzers (such as the tools from KEDR framework) to detect different kinds of errors: memory leaks, etc.
All that was primarily intended for x86.
While it might be possible to port the tests themselves to ARM, one will need to choose the analyzers that work on that platform too. KEDR tools are currently for x86 only but one may try Kmemleak, Fault injection facilities and other tools on ARM instead.
Spruce seems to be a work in progress still. I see, you opened a ticket concerning ARM support in their issue tracker, I think, it is the right thing to do.
I would also suggest to take a look at Phoronix Test Suite. It is currently widely used for testing and benchmarking, including the analysis of file system kernel modules. See this article for example. It seems to work on ARM although I haven't tried it there myself.
The best tool for testing/validating a file system is xfstests. I have written tools to make it easy to validate xfstests for ext4. See: http://thunk.org/gce-xfstests for more details.
There is also an alpha-test level support for using this on ARM directly: http://thread.gmane.org/gmane.comp.file-systems.ext4/53649/focus=53659
This has been used successfully to test ext4 on an Android device, although to be honest, most of the time what I do is to bludgeon an Android kernel until it will build on x86, and then use kvm-xfstests gce-xfstests, since it's much more convenient. In particular with gce-xfstests, I can just do a "fire and forget", and then when the test completes I get a test report in my e-mail. Where as with the Android arm xfstests tarball, the automation isn't done yet, so you have to manually set up an external USB-attached USB device, hook it up via some kind of USB C hub, or if you are going to use an OTG usb adapter, you need to make sure the Android device can receive power while it is also driving the OTG usb port --- and you have to manually set up the chroot. Unless the BSP kernel has been badly abused so you can't figure out how to make it build on x86 (getting the MSM kernel to work on x86 wasn't easy) testing on gce-xfstests may be much simpler at the end of the day.
I'd like to collect some ideas about the solution of following problem.
I've got a TOF camera, and its driver for linux x86/64. It works fine. But in fact the camera would be used on an ARM based embedded device if that's possible.
Questions:
should I have to decompile the driver binaries and recompile with ARM compiler? is there any available decompiler tool?
is there any ARM>>x86 emulator which is available?
any other ideas?
ps: the pure source is very expensive, so I don't like to purchase it anyway :)
AFAIK, as of today, there's no such decompiler that will generate compilable code from machine code. You will have to manually fix (usually a LOT of fixes) the generated code. You can check this question for Linux decompilers.
Check QEmu. Underlying architecture is not relevant as long as you can execute it ;)
There's not much besides what you've stated.
What you're attempting is (in part) reverse engineering. RE is a complex process and requires great knowledge in the thing you're attempting to reverse; in your case camera drivers. If you have knowledge in this area, go ahead. If you don't, I wouldn't waste my time on it (or get the knowledge first ;))
See the following answer for details. It lists some of the problems you could encounter attempting to automate such a translation:
Convert object file to another architecture
Recently created Eltechs ExaGear Server, available on ARM as A Service, runs x86 applications on ARM devices.
It is new and proprietary, but it does exist.
If your driver is a kernel object, there is no emulator (to my knowledge) capable of running x86 kernel code inside ARM kernel. If your "driver" is in fact a userspace library hacked on top of a generic driver (v4l2, etc.), you may have luck with QEMU or Exagear mentioned here. As a side note, you will probably end up with an x86 application software, too, as calling an x86 library from ARM code is not supported by QEMU or Exagear out of the box.
I have a Linux network driver that was originally written for 2.4 kernel. It works perfect.
I want to port it to kernel 2.6.31 and then to ARM Linux with same kernel i.e. 2.6.31. I have actually done some minor changes to the driver so that it is able to compile under kernel 2.6.31 and it also loads and unloads without crashing. It also cross compiles for the ARM Linux. But I am unable to test it on ARM so far.
How do I check that the driver is fully compatible with the target kernel, and what considerations shall be made to make it compatible with ARM.
The driver is a virtual network device driver.
Thanks in advance.
Maybe you could use Qemu ( http://wiki.qemu.org/Main_Page) to emulate an ARM platform to be able to test your driver.
You cannot check the driver like that - you have to consider the API changes within 2.6.x series kernel. The changes are quite significant and the overall of the API's from the 2.4 series which is not currently in use.
I would suggest you to go here to the Amazon book store for this book in particular. The book is called 'Essential Linux Device Drivers', by Sreekrishnan Venkateswaran. A very well detailed explanation that will be your guidance in ensuring it works properly.
Since you mentioned the device driver is a network, presumably char device (You're not accessing it in blocks), well, the good news is that the 2.6.x series kernel APIs for the character devices are significantly easier and more centralized to focus on - in fact a lot of the framework is already in place in which the author of said book explains very clearly.
By the way, the book focusses on the latter 2.6.x series after 2.6.19, so this will help you clue in on what needs to be done to ensure your driver works.
You did not specify the ARM chipset you're targetting?
As for testing... well.. perhaps the best way to do this, this is dependant on how you answer the above question to you regarding ARM chipset - if its ARMv6, then perhaps, a cheap android handset that you can easily unlock and root, and pop the kernel in there and see what happens - sorry for sounding contrived but that's the best thing I can think of and that's what pops into my head, to enable you to test it out for ease of testing :)
PS: A lot of cheap ARMv6 handsets would have kernel 2.6.32 running Froyo if that's of any help!
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.