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Interest in Embedded Linux Remains Low
burnin1965 writes "According to EE Times interest in embedded linux remains low. I was surprised to see their headline considering I just purchased a Sony TV which runs linux and I assisted my brother in setting up an Actiontec DSL modem which runs linux. A few years back I had only heard of devices that ran embedded linux and now that they are starting show up everywhere interest is low? The survey did bring up three issues which should be addressed by the embedded linux community, whether those issues are misconceptions or actual problems. 1) Incompatibility with software, applications, and drivers. 2) Performance or real time capability. And 3) support."
My D-Link DSL604t is Linux based too, and so is my PDA..
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I developed an embedded device using NetBSD. I would love to use Linux, but the agressive stance of the GPL license (Linksys!!) keeps me away. I know many others that share the same view.
Linux won't take over the embedded world, mainly becuase embedded is a commercial market. Who wants to invest money in developing a product, only to have the open source community go after you? And you get bashed for trying to earn a living.
Before you flame me, I did make a good portion of the code used in my embedded device available to the BSD community. I won, they won. Nobody twisted my arm.
I'm posting AC, STOP KARMA WHORING!!!
TDT
Issue 1 is not a big problem. The programming model is well-understood, so at the application level there really isn't a lack. However, there is little support for specific stuff that hardware vendors may want to do (like say a CDMA RIL) and the implementation of those features is pretty difficult.
The second issue is a real concern. User experience is significantly degraded when the interrupt latency is longer than the expected reaction time. There are ways to reduce the interrupt latency in Linux, but the side effects are undefined.
Support is only an issue because it is so expensive. Likewise, there are only a few top-tier Linux vendors who can offer good support. Montavista, for example, is one of the premier (if not the premier) embedded Linux vendors, but they can't support everyone who wants to build a Linux-based embedded solution. They pick and choose their support contracts, and anyone not selected needs to find someone else with the relevant support capabilities.
A lot of DVD players probably are Linux based, though.
...without knowing it. as i've pointed out before you can download sources for Sony devices from here: http://www.sony.net/Products/Linux/Download/search .html
anyone got anything on the list? [hint: try under the 'game' section]
One issue that prevents linux being used in automotive systems is the ability of a vendor to accept liability (and be in a position to defend it meaningfully).
Auto companies get sued all the time (rightly and wrongly), as to their major suppliers (Delco, Denso, Bosch etc.). If a supplier's part is defective, a class action against the supplier may result. If the supplier is big like Delco they'll be in a position to defend against that action, and have enough money and insurance to survive if they lose the action.
But linux comes largely from little guys like Montevista. Even if they do accept liability, they're still too small to survive a huge automotive-defect class action. So GM or Toyota or BMW would be left holding the bill. The major automotive electronics suppliers will accept liability, and are big enough to be credible partners in a litigative society. Microsoft sells (very limited) automotive electronics products, and are again credible (from a business perspective).
IBM could sell automotive linux, as could HP, but they don't (or rather they want to supply technology to automotive electronics partners).
Now why don't guys like Denso install linux - at least partially because they all want to be little microsofts, to "own the car", and open systems and generic technogies prevent that - they think they benefit from wacky proprietary OSes and weird undocumented software stacks.
This, sadly, is very much an pointy-headed-boss driven decision. From the perspective of the HW/SW teams its just plain stupid. The problems are probably pretty representative why those 66% aren't looking into Linux.
Its gross overkill. Linux architecture is for general-purpose multi-user information processing loads. It does a whole bunch of things that are simply ballast for an O.S. that is there simply to control some special-purpose hardware and run a simple on-screen-display. Bigger micro, larger flash footprint, more on-chip RAM gobbled. This really really hurts in a genuinely cost-competitive marketplace. If you're building an Net appliance type of thing of course Linux is almost a turn-key solution. For embedded control... its the wrong kind of OS.
Licensing is a pain if you have non-trivial know-how you don't what to gift your competitors realised in your Firmware. You end up doing really vile hacks like doing stuff in user space via 'dummy drivers'. Debugging becomes fun fun fun....
The abstract machine doesn't fit. In the embedded control space sometimes the cleanest solution really is to do direct HW access. However, the hard kernel/userland divide of Unix O.S. makes doing this in a systematic, safe, way rather clumsy. You end up writing around a bazillion special-purpose HW-dependent ioctl's where what you really wanted was some selective access to the I/O bus. Then you need a HW workaround with hard real-time requirements and the 'fun' really starts.
In short Linux is a fine information processing
That's ridiculous. Just because something has a processor in it doesn't mean it's running an operating system.
Most embedded products still run on simple 8 bit microcontrollers. These all run some software, but most don't run anything that could be called an operating system.
Think along the lines of a PIC microcontroller that spends it's life waiting for a button press or watching an analog input level and responding to it in some fairly simple way. The code that runs on this will probably be a simple loop that runs without any OS support. It probably won't even be using interrupts.
Even more complex products that use 16 or 32 bit microcontrollers / DSPs will often skip the OS. These systems frequently run from internal memory and are therefore limited to a few hundred K of program space and even less RAM. In this world the OS is a big expensive component that's often not necessary for the proper function of the system.
Don't know if any /.ers are familiar with the mixing console industry, but Midas are doing some pretty neat things with Embedded Linux on their new digital console (XL8).
Could not open
There's a fundamental misunderstanding here - GOOD Hardware engineers start out by asking "What OS vendor are you going to use?" before buying an eval board and dictating what OS to use by their choice of processor vendors.
It's true that once the OS and eval boards are selected, a BSP has to be created by one of those vendors. This is much further down the line and usually must be well thought out in order for a project to be successful. Working with MontaVista is a pain, though.
Not to be a shill for Cirrus Logic for a moment, but another route that I find interesting is the route that Cirrus is taking with their ARM9 processors. You can download a full BSP for free without having to go through these third party BSP vendors. http://arm.cirrus.com/
Ultimately, a system improperly architected will fail in cost, schedule, and/or reliability. Processor/OS selection is just one of those steps.
Nietzsche is dead. --God
This is interesting stuff, as Linux, although behind Windows embedded in certain device types like smartphonse, is constantly gaining market share, and clearly leads in devices like firewall, router and wifi appliances.
-FreakGeek
Related to that principle, to avoid licensing fees for WinCE, you'll be willing to write your own drivers for a large-scale product, especially since it's one you designed and manufactured yourself. Microsoft doesn't write drivers for Sony televisions, after all.
17% of embedded market is absolutely amazing imho. Unlike PCs, there are many choices for an embedded operating system. Most commercial embedded OS vendors could not even dream about reaching such high audience. I've read somewhere (and I agree) that if you need a filesystem and/or a TCP/IP stack you should consider Linux for an embedded system.Maybe I would expand this to include a USB host. If you don't need TCP/IP stack/Filesystem/USBhost then my personal favorite is Labrosse's microC/OS-II (amazing collection of CPUs that will run this, starting with 4K-ROM 8-bit processors to PowerPC type processors, not many OSes can claim such diversity).
I've just learned that modern versions of the wrt54G are vxworks based, but the old versions are still out there that are linux based so my point still stands as the example is mirrored in other linux based products.
Not saying linux is better, but I am questioning whether it is worse in an embedded environment, or if it's about the same...
However, what's NOT being reported by the EE Times is what's significant here.
If you look at the linuxdevices.com survery, the number of systems using linux is about 20-25% IIRC. Say it's 20%. This is in line with the survey.
But the REAL interesting thing here is that Linux has come from virtually nowhere in the past 5 years, to now actually become one of THE dominant Embedded OS's in the marketplace, if not the single most dominant one.
Contrast this to VxWorks. About 5-6 years ago, WindRiver was crowing that they had the dominant OS, with about a 33% marketshare. According to the linuxdevices.com survery, that has now dropped to about 12% IIRC, and is fading. Witness, in fact, WindRiver's huge adoption of Linux recently (and their large hiring of Linux developers).
Microsoft's OS's are each well behind Linux; and even combined, still add up to slightly less marketshare (or at best, comparable) than Linux.
So, the bottom line is that Linux has come from absolutely nowhere in the past 5 years to become one of the key players in the embedded space. Completely contrary to the EE Times article. Shame on them for their attempt to completely distort the truth here.
Linux in the embedded space is only going to keep on growing; the advantages with it over the closed-source solutions are just too huge.
The best way to predict the future is to create it. - Peter Drucker.