Re: [Embeddedxen-devel] Status of this project and relationship with XEN-ARM?

[ROSSIER D. <Dan...@he...>]

> -----Original Message-----
> From: Charles Woloszynski [mailto:charles.woloszynski@packet-
> dynamics.com]
> Sent: mercredi 13 janvier 2010 19:14
> To: emb...@li...
> Subject: [Embeddedxen-devel] Status of this project and relationship with
> XEN-ARM?
> 
> I am looking to run Xen on an ARM processor. I have found both this project
> and the Xen ARM work and I am trying to understand their relationship.
> 
> Is there any relationship between these?  Which is more current?

Xen ARM mainly focuses on security and ACM issues in general and has been developed by Samsung which
has quite a lot of commercial constraints on their efforts, so I can not state about the ongoing work and status.
EmbeddedXEN focuses on realtime systems aspects; we have developed a particular dom U (called domU U-RT) which
relies on Xenomai interfaces (http://www.xenomai.org). We remove the I-pipe nanokernel mechanism which is used
by Xenomai to process interrupts and control the access to hardware from non-realtime execution domain.

We originally based our port on Xen ARM's one, but brought quite a lot of changes and also various fixes specific to our environment.

> 
> I am ultimately looking to run Android under Xen?  Has that been done for
> this?
> 
> Can I build embeddedXen and run it under the Android QEMU emulator?

Concerning Androïd,   it depends on what kind of ARM core are you using (if it is compliant with armv5 instruction set and MMU, it is OK), otherwise you need to adapt
some arch-dependent code of the hypervisor. This should be possible providing some minimal efforts. However, Android itself needs to get paravirtualized; it means you have to adapt
the OS at the IRQ, timer, memory access, etc. layers in order to be compliant with the hypervisor API (hypercalls/upcalls). In EmbeddedXEN, most of XEN API has been moved into a dedicated directory (xen_guest) at the root of the source tree.


> 
> Thanks in advance,
> 
> Charlie
> 
> 

Daniel