From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergei Organov <osv@javad.ru>
To: Nick Garnett <nickg@cygnus.co.uk>
Cc: ecos-discuss@sourceware.cygnus.com
Subject: Re: [ECOS] On demand FP context switch major problem.
Date: Fri, 02 Jun 2000 06:47:00 -0000
Message-id: <87hfbckxef.fsf@osv.javad.ru>
References: <87u2fwt559.fsf@osv.javad.ru> <poaehohucn.fsf@balti.cygnus.co.uk> <87puqjt0p5.fsf@osv.javad.ru> <877lcarg0h.fsf@osv.javad.ru> <povgzure5w.fsf@balti.cygnus.co.uk> <874s7dpwtv.fsf@osv.javad.ru> <poya4p3asn.fsf@balti.cygnus.co.uk> <874s7cmhcs.fsf@osv.javad.ru> <posnuw2rpf.fsf@balti.cygnus.co.uk>
X-SW-Source: 2000-06/msg00038.html

Nick Garnett <nickg@cygnus.co.uk> writes:
> Sergei Organov <osv@javad.ru> writes:
[...]
> > 
> > Possibility to configure eCos to use simple variant of FP context switch still
> > remains. If application requires FPU even in ISRs/DSRs/alarm handlers, then
> > it's likely that most of tasks require FPU as well, so there is no reason to
> > use on-demand context switch implementation that has some overhead anyway.
> 
> I suspect that this is the best approach to this problem. At least for
> the present, or until someone works out how to do it properly. I would
> much rather not provide a facility than supply a badly thought-out or
> poorly implemented version.

Exactly. So I'll focus on implementing on-demand without capability to use FP
in ISRs/DSRs, and leave capability to use FP in ISRs/DSRs only when simple FP
context switch policy is configured.

> 
> -- 
> Nick Garnett
> Cygnus Solutions, a Red Hat Company
> Cambridge, UK

BR,
Sergei.