From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philippe Gerum In-Reply-To: <200903271641.09389.pwaechtler@domain.hid> References: <200903271538.10434.pwaechtler@domain.hid> <49CCE84E.7060708@domain.hid> <200903271641.09389.pwaechtler@domain.hid> Content-Type: text/plain; charset="UTF-8" Date: Fri, 27 Mar 2009 16:59:43 +0100 Message-Id: <1238169583.6815.241.camel@domain.hid> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: Re: [Xenomai-core] use case: possible to boot Posix subsystem in <50ms and then Linux? List-Id: "Xenomai life and development \(bug reports, patches, discussions\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: pwaechtler@domain.hid Cc: xenomai@xenomai.org On Fri, 2009-03-27 at 16:41 +0100, Peter W=C3=A4chtler wrote: > Am Friday 27 March 2009 15:53:02 schrieb Gilles Chanteperdrix: > > > > Xenomai kernel-space support is started somewhere in the middle of th= e > > boot process, so, you can probably start kernel-space applications at > > that time. User-space only works when init has been started, which > > happens a bit later during the boot process. But you can start Xenoma= i > > applications before all the system services have been started. > > >=20 > I think the fundamental question is: does Adeos provide a scheduler?=20 >=20 No it does not. Not the kind of scheduler you seem to be thinking of actually; it only "schedules" interrupt and trap events. Not tasks. > And I guess the answer is yes, at least "Life-with-Adeos" doc mentions > primary and secondary execution modes/domains. >=20 This is dealt with by the Xenomai nucleus. Adeos provides the simplistic "domain" abstraction, and Xenomai derives the primary/secondary mode abstractions on top of those. > In the use case it would be necessary that OSEK subsystem is able to sc= hedule=20 > between a static number of preconfigured threads WITHOUT the preconditi= on=20 > that Linux is up and running. >=20 The way to do this would be to port the Xenomai nucleus and portions of the POSIX skin over bare metal. I did exactly that once over an ARM ISS, so this is indeed doable to bypass Linux. The point is: this needs a full-fledge Xenomai port, a bit like the Xenomai event-driven simulator interfaces to our RTOS core. > > > > As a side note, I have a question for the automotive industry people. > > Would there be an interest in developing an OSEK skin for Xenomai? I > > have been thinking about that for some time, but still have not found > > time to start the job. I have read the OSEK spec, and found the > > interface pretty simple (though some part of the job has to be done > > offline, and annoyingly need to read XML files). The OSEK com spec, o= n > > the other hand, looks rather scary. >=20 > There are open source OSEK implementations. AFAIK, all far from complet= eness. >=20 > You can start with > http://opensek.sourceforge.net/ >=20 > or have a look at the list at=20 > http://en.wikipedia.org/wiki/OSEK >=20 > Peter >=20 > _______________________________________________ > Xenomai-core mailing list > Xenomai-core@domain.hid > https://mail.gna.org/listinfo/xenomai-core --=20 Philippe.