In-production with Nios/uCLinux?

[Altera_Forum]

Group, 

 I've been working on the development of a product that would include a seperate ARM processor running Linux connected to an Altera FPGA.  Now, recent specification changes would allow me to integrate all CPU functionality in NIOS and onto the FPGA. However, some flavor of Linux is still very important to the product.  After looking at the online documentation and support sites, I am somewhat concerned that uCLinux for NIOS is not very mature.  How many of you actually have a NIOS-based unit IN PRODUCTION with uCLinux running as your OS?  I am very interested to know how "production-proven" the port is. Obviously most of the kernel itself has been merged into mainline, but what about drivers and all of the other support functionality?  Thanks,  espian

[Altera_Forum]

I have worked for 2 clients in particular that will be putting it into production shortly. So far, there have been no reliability issues. Although myself, I am still scepticle over how stable it will be given the nature of FPGAs themselves.

[Altera_Forum]

--- Quote Start ---  originally posted by jdhar@Jun 6 2006, 08:23 AM i have worked for 2 clients in particular that will be putting it into production shortly. so far, there have been no reliability issues. although myself, i am still scepticle over how stable it will be given the nature of fpgas themselves. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=15964)  --- quote end ---    --- Quote End ---    "Although myself, I am still scepticle over how stable it will be given the nature of FPGAs themselves."  What do you mean exactly? http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/blink.gif

[Altera_Forum]

In my mind, FPGAs aren&#39;t as stable as lets say off-the-shelf processors. For example, there are problems on configuration sometimes from powerup, so you have to accunt for that in circuitry (CRC checking). Also, I have had problems with the Avalon fabric itself locking up, so that has reduced my trust in FPGAs. These are just a few of the issues. Also, I haven&#39;t subjected them to temperature variations, so that&#39;s a big Q-mark for me.

[Altera_Forum]

--- Quote Start ---  originally posted by jdhar@Jun 7 2006, 09:32 AM in my mind, fpgas aren&#39;t as stable as lets say off-the-shelf processors. for example, there are problems on configuration sometimes from powerup, so you have to accunt for that in circuitry (crc checking). also, i have had problems with the avalon fabric itself locking up, so that has reduced my trust in fpgas. these are just a few of the issues. also, i haven&#39;t subjected them to temperature variations, so that&#39;s a big q-mark for me. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16000)  --- quote end ---    --- Quote End ---    Oh Ok.  Regarding to temperature issues, I developped many FPGA design for my company, and each time we had to subject them to temperature variations (-30 °C/+70°C). And believe me, if your design is well coded (fully synchronous especially ), it works.  Regarding to avalon fabric bug. What can be said ? ASIC are also prone to mask bug. With an ASIC , you have to wait for a new mask. With an FPGA you have to wait for a new design. So...  By the way, what other issues do you talk about ?

[Altera_Forum]

Maybe I am lucky. I had more than a dozen of nios/nios2 designs. Some had shipped more than 100k pcs. There aren&#39;t issues in power-on config or temp. (of cours, be careful in your design.) I feel the quality of altera&#39;s fpga is excellent.

[Altera_Forum]

Wow, I&#39;m impressed with the number of designs that you&#39;ve put into production! 

 How many of them also utilized uCLinux?  Thanks.

[Altera_Forum]

--- Quote Start ---  originally posted by espian@Jun 7 2006, 11:31 PM wow, i&#39;m impressed with the number of designs that you&#39;ve put into production!  how many of them also utilized uclinux?  thanks. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16004)  --- quote end ---    --- Quote End ---   Not yet. I started uClinux for new products this year. I did have a hard time initially. But now things move smoothly. The first one with uClinux should be out this month.

[Altera_Forum]

--- Quote Start ---  originally posted by hippo+jun 7 2006, 08:16 pm--><div class='quotetop'>quote (hippo @ jun 7 2006, 08:16 pm)</div>  --- quote start ---  <!--quotebegin-espian@Jun 7 2006, 11:31 PM wow, i&#39;m impressed with the number of designs that you&#39;ve put into production!  how many of them also utilized uclinux?  thanks. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16004)  --- quote end ---    --- Quote End ---   Not yet. I started uClinux for new products this year. I did have a hard time initially. But now things move smoothly. The first one with uClinux should be out this month. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16012)</div> [/b]  --- Quote End ---    Hi Hippo,  I&#39;m facing with the same problem as Espian . I plan to use NIOS2 for a new design in production, so I&#39;would like to know if this solution is really robust. When you say "hard time initially", do you mean NIOS2 related problems or more uClinux related problems ?  IMO the 2 things are different, because I think that starting into uCLinux is a big task, whatever the target is (NIOS2, ARM...) ?  Moreover, would it be possible to know what kind of product you develop (if it not secret http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/smile.gif ) ?  Regards.

[Altera_Forum]

Hi bigboss25, 

It was uClinux. I was a newbie to uClinux. It takes some time to learn. For my current application, the Nios2 + uClinux solution works as expected. Yes, it is robust.

[Altera_Forum]

--- Quote Start ---  originally posted by hippo@Jun 8 2006, 03:05 AM hi bigboss25, it was uclinux. i was a newbie to uclinux. it takes some time to learn. for my current application, the nios2 + uclinux solution works as expected. yes, it is robust. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16024)  --- quote end ---    --- Quote End ---    Thx Hippo.One more question , what is your background : electronic or software engineer ?

[Altera_Forum]

<div class='quotetop'>QUOTE </div> 

--- Quote Start ---  Hippo, what is your background : electronic or software engineer ?[/b]  --- Quote End ---   Major in EE, plus some CS. I designed ASIC and boards. I wrote desgin tools, firmware, and apps.  How about you?

[Altera_Forum]

Hi,hippo 

  I am a newbie to nios , but i want to embedd ucliunix. could you give some help to instruct me ? how can i learn about ucliunix? could you recommend some books and reference? thanks a lot   tony

[Altera_Forum]

--- Quote Start ---  originally posted by tony@Jun 9 2006, 08:20 PM hi,hippo      i am a newbie to nios , but i want to embedd ucliunix. could you give some help to instruct me ? how can i learn about ucliunix? could you recommend some books and reference? thanks a lot   tony <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16061)  --- quote end ---    --- Quote End ---   I was a newbie too. We have a nios wiki, and we can share. http://nioswiki.jot.com/wikihome/operating...ms/%c2%b5clinux (http://nioswiki.jot.com/wikihome/operatingsystems/%c2%b5clinux)

[Altera_Forum]

thanks a lot

[Altera_Forum]

--- Quote Start ---  originally posted by bigboss25+jun 7 2006, 09:47 am--><div class='quotetop'>quote (bigboss25 @ jun 7 2006, 09:47 am)</div>  --- quote start ---  <!--quotebegin-jdhar@Jun 7 2006, 09:32 AM in my mind, fpgas aren&#39;t as stable as lets say off-the-shelf processors. for example, there are problems on configuration sometimes from powerup, so you have to accunt for that in circuitry (crc checking). also, i have had problems with the avalon fabric itself locking up, so that has reduced my trust in fpgas. these are just a few of the issues. also, i haven&#39;t subjected them to temperature variations, so that&#39;s a big q-mark for me. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16000)  --- quote end ---    --- Quote End ---    Oh Ok.  Regarding to temperature issues, I developped many FPGA design for my company, and each time we had to subject them to temperature variations (-30 °C/+70°C). And believe me, if your design is well coded (fully synchronous especially ), it works.  Regarding to avalon fabric bug. What can be said ? ASIC are also prone to mask bug. With an ASIC , you have to wait for a new mask. With an FPGA you have to wait for a new design. So...  By the way, what other issues do you talk about ? <div align='right'><{post_snapback}> (index.php?act=findpost&pid=16001)</div> [/b]  --- Quote End ---    I&#39;m glad to see that you have seen them proven in a wide temp. range. But just to be clear, I&#39;m not making the argument that you should design your own ASIC over using an FPGA. FPGAs are great for quite a number of applications, and since I haven&#39;t done the necessary testing with the NIOS myself, I am just speculating at this point. However, getting an off the shelf processor that has been proven, with all of it&#39;s issues documented (if any), I think it would be safe to say that offers some security. I recognize that fixing bugs and documenting them all comes with time, and given the relative immaturity of NIOS 2, it&#39;s done quite well for it&#39;s lifespan. I just don&#39;t think it&#39;s at the point of maturity of lets say an Intel XScale. Take the lockup issue; I have been talking to altera reps for almost two months now, and not much has come out of it, even though they recognize the problem themselves. If a customer was to put out a design that used my specific setup which caused lockups, they would be in a lot of trouble since they had no prior knowledge of this, because it&#39;s not documented. Again, this will come with time...  Please don&#39;t think I&#39;m knocking FPGAs and NIOS. I have developed quite a few products around it myself (not as many as hippo!), so I obviously believe in it&#39;s potential. I&#39;m just a bit hesitant in putting it with the same class as the other big-boys... maybe that hesitation is warranted, maybe not, I don&#39;t know.  You asked about other issues I had... one in particular simply relates to the efficiency of such important cores as the DDR IP Core. If there are two cores that need to be working well together at all times, it shoudl be the NIOS and the memory core. I haven&#39;t found this to be true at all times. But of course, this is cured easily with upgrades...  Hope this clarifies.

[Altera_Forum]

I have been dealing with "beta" always. Either chips deveveloped ourself, or early beta chips from vedors, there may be just a lot of bugs and unknown issues. I use beta software, too. "Mature" may mean "out of date" for me. I need cutting-edge technology that I can get more chance to win in the ever-changing world. But this may not be the life for everybody. 

 The first thing to note, when working with company of this size, is to have the right contact window. They have their priority customers. The higher level you meet, the more power you will have. So don&#39;t satified with your local rep, if you have a big ambition.  Next, in your design, always start with given examples from vendors. Things might not work from another direction (or usually not work). Document writers are (usually) not developors. Document can be wrong and out of date. Some important issues may be undocumented or unpublic. You should try to contact developers, but it may be difficult.