Subject: Re: Real Time NetBSD & Assembly [Re: how to detect if kernel is running in interrupt ctx]
To: Sam Thigpen <sthigpen@sdf.lonestar.org>
From: Simon Burge <simonb@wasabisystems.com>
List: tech-kern
Date: 07/07/2003 19:08:25
Sam Thigpen wrote:

> I have seen several threads on real time NetBSD.  The ucr supplement with
> assembly code for the O'Reilly Book Programming Linux Device Drivers is
> pretty good.  With the advent of NASM, and other mature assemblers, I was
> wondering about this approach for writing real time device drivers.  A real
> time kernel is needed as well, of course.  The base RTAI Linux code
> doesn't look too huge, though it may need a lot of modifications for use
> with NetBSD.

With support for at least 12 CPU architectures in our source tree, most
of which can share drivers, this would lead to a _lot_ more work.  Also,
I'd guess that gcc can generate better (and certainly more error-free)
code that most people can by hand.  Code review is certainly a lot
easier too with C than assembly code.

Note I haven't looked at the book or RTAI that you mention.

Simon.
--
Simon Burge                            <simonb@wasabisystems.com>
NetBSD Support and Service:         http://www.wasabisystems.com/