Re: OS porting on Xen on ARM

[Arianna Avanzini <avanzini.arianna@gmail.com>]

On 12/17/2013 12:05 PM, Dario Faggioli wrote:
> Hi Arianna!
> 
> First of all, some context for the Xen on ARM people that I'm Cc-ing. 
> Arianna will be working on porting an embedded --targeted specifically at
> automotive-- OS on top of Xen on ARM. The OS is Erika, and Claudio could
> give any kind of information about it (and correct me, if I said something
> wrong): 
> http://wiki.automotive.linuxfoundation.org/index.php/Erika_Enterprise_Open-Source_RTOS
>
> 
http://erika.tuxfamily.org/
> 
> This mail is mainly meant at giving her some clues and pointers about how
> to get on with it. I'll do my best but, given it's ARM, with which I'm not
> super familiar with, feel free to chime in and fill the gaps or correcting
> the mistakes I may make.
> 
> The goal is (for now) to have the Erika OS running as a DomU, on top of a
> Linux Dom0. She'll be using a Cubie* as a platform. There is definitely
> some similar/related activity going on (writing/porting embedded OSes on
> Xen) these days, but, if I'm not mistaken, this would be the first example
> of doing it on ARM (except, perhaps, from Julien's work on FreeBSD, but
> that's not embedded! :-P)... Pretty cool, eh?
> 
> Arianna, all the information about running Xen on Allwinner is here: 
> http://wiki.xen.org/wiki/Xen_ARM_with_Virtualization_Extensions/Allwinner 
> Also, there is a thread right about this on xen-devel going on in these. 
> Perhaps you can have a look at it: 
> http://bugs.xenproject.org/xen/mid/%3CWC20131216075445.88000B@perkbv.com%3E
>
> 
(look at the whole thread, e.g., via marc.info).
> 
> About Xen in embedded in general, there has been a thread recently, which
> may contain some useful info. In case you want to skim through it, here it
> is: 
> http://bugs.xenproject.org/xen/mid/%3C1384802050.16918.219.camel@Solace%3E
> 
> About how a small, and an hopefully easy enough to understand, OS that runs
> as a Xen DomU looks like, check out Mini-OS in the Xen Source tree: 
> http://xenbits.xen.org/gitweb/?p=xen.git;a=tree;f=extras/mini-os;hb=HEAD As
> I said, it's small, and definitely simpler, for instance, than Linux, but
> it's quite feature complete, which is something you probably won't need.
> 
> In fact, there are people working on even smaller and simpler solutions, 
> for the most diverse purposes. Some links below (again, check the entire 
> threads): 
> http://bugs.xenproject.org/xen/mid/%3Cem4158cadd-9eab-4a26-80ba-b3a3b311bee2@smartin-alien%3E
>
> 
http://bugs.xenproject.org/xen/mid/%3Cem40e5807b-ac20-4c2a-ad66-d1056397e07b@smartin-alien%3E
> http://bugs.xenproject.org/xen/mid/%3Cembc004940-1dbb-4924-bbab-76901c75e44e@smartin-alien%3E
>
> 
http://osdir.com/ml/general/2013-12/msg26912.html
> http://bugs.xenproject.org/xen/mid/%3C723A93B1-0345-42C6-949B-F6070CE40043@recoil.org%3E
>
>  Simon also sent the code out already, here:
> https://github.com/FurryFuttock/micro-pv For anything about MirageOS:
> http://openmirage.org/ , https://github.com/mirage/
> 
> In case you need something bigger, Julien ported FreeBSD on Xen on ARM (as
> a DomU). That lives here (Julien, correct me if I'm wrong): 
> http://xenbits.xen.org/gitweb/?p=people/julieng/freebsd.git;a=shortlog;h=refs/heads/xen-arm
>
> 
I expect this to be super-overkill, but perhaps it could help to get an
> idea of what an actual port (rather than a 'write from scratch') would 
> require.
> 
> Last but not least, the hypercall interface official documentation is all
> in the public header files, in the repository, as well as here: 
> http://xenbits.xen.org/docs/unstable-staging/hypercall/index.html 
> http://xenbits.xen.org/docs/unstable-staging/hypercall/arm/index.html
> 
> That is all for now I guess... Ask if there is anything you do not 
> understand that you think this community could help with. :-)
> 

Thank you for the very useful pointers, I've started to carefully read the
threads you recommended and to study the code of the mini-os. I'll definitely
check out also the other OSs you suggested.
Thank you also for being so helpful, I surely won't hesitate to ask in case
anything is not clear enough to me (hoping I won't be too much annoying).


> Best Regards, Dario
> 


-- 
/*
 * Arianna Avanzini
 * avanzini.arianna@gmail.com
 * 73628@studenti.unimore.it
 */