From: Chris Friesen <cfriesen@nortelnetworks.com>
To: VINOD GOPAL <vinod_gopal74@yahoo.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: arithmetic functions for linux driver
Date: Wed, 17 Mar 2004 13:17:30 -0500 [thread overview]
Message-ID: <4058963A.6060805@nortelnetworks.com> (raw)
In-Reply-To: 20040317175939.75460.qmail@web60705.mail.yahoo.com
VINOD GOPAL wrote:
> Hi,
> I am new to linux world and this mailing list.
>
> I need to use the arithmetic functions like sin, cos,
> exp, log, etc in linux device driver.
>
> On search read , not to use libm from kernel driver
> as it will harm the fpu registers.
>
> Do you have any insight how to support these
> functions in linux driver or any code that is
> available which I can make use of?
Best would be to try and have userspace do it for you.
If you really need to do it in the kernel on the fly, you'll need to either
1) save and restore the floating point context yourself
2) use fixed point calculations
As an optimization for 2, you could pre-calculate some lookup tables and
interpolate.
Chris
--
Chris Friesen | MailStop: 043/33/F10
Nortel Networks | work: (613) 765-0557
3500 Carling Avenue | fax: (613) 765-2986
Nepean, ON K2H 8E9 Canada | email: cfriesen@nortelnetworks.com
next prev parent reply other threads:[~2004-03-17 18:17 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-03-17 10:44 Linux 2.4.25, nfs client hangs when talking to a MacOS nfs server Charles-Edouard Ruault
2004-03-17 16:58 ` Trond Myklebust
2004-03-17 17:41 ` Charles-Edouard Ruault
2004-03-17 17:41 ` Charles-Edouard Ruault
2004-03-17 17:41 ` Charles-Edouard Ruault
2004-03-17 17:59 ` arithmetic functions for linux driver VINOD GOPAL
2004-03-17 18:11 ` John Bradford
2004-03-17 18:15 ` VINOD GOPAL
2004-03-17 18:50 ` Richard B. Johnson
2004-03-17 20:27 ` John Bradford
2004-03-17 18:17 ` Chris Friesen [this message]
2004-03-17 18:36 ` Richard B. Johnson
2004-03-17 23:21 ` Peter Williams
2004-03-17 18:01 ` Re: Linux 2.4.25, nfs client hangs when talking to a MacOS nfs server Chris Croswhite
2004-03-17 18:16 ` Trond Myklebust
2004-03-17 19:28 ` Charles-Edouard Ruault
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