From owner-freebsd-current@freebsd.org  Sat May 26 10:11:10 2018
Return-Path: <owner-freebsd-current@freebsd.org>
Delivered-To: freebsd-current@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9C227F7038E
 for <freebsd-current@mailman.ysv.freebsd.org>;
 Sat, 26 May 2018 10:11:10 +0000 (UTC)
 (envelope-from kostikbel@gmail.com)
Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 1A6FF6A0AD
 for <freebsd-current@freebsd.org>; Sat, 26 May 2018 10:11:09 +0000 (UTC)
 (envelope-from kostikbel@gmail.com)
Received: from tom.home (kib@localhost [127.0.0.1])
 by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id w4QAAxnC034995
 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO);
 Sat, 26 May 2018 13:11:02 +0300 (EEST)
 (envelope-from kostikbel@gmail.com)
DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua w4QAAxnC034995
Received: (from kostik@localhost)
 by tom.home (8.15.2/8.15.2/Submit) id w4QAAx2Q034994;
 Sat, 26 May 2018 13:10:59 +0300 (EEST)
 (envelope-from kostikbel@gmail.com)
X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com
 using -f
Date: Sat, 26 May 2018 13:10:59 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Johannes Lundberg <johalun0@gmail.com>
Cc: freebsd-current <freebsd-current@freebsd.org>
Subject: Re: Floating point in kernel?
Message-ID: <20180526101059.GM88128@kib.kiev.ua>
References: <CAECmPws88aex8zpis5CMD4uvqxF33810jimVy3sHYJGyq+PCCw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAECmPws88aex8zpis5CMD4uvqxF33810jimVy3sHYJGyq+PCCw@mail.gmail.com>
User-Agent: Mutt/1.10.0 (2018-05-17)
X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00,
 DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no
 autolearn_force=no version=3.4.1
X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on tom.home
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.26
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
 <freebsd-current.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current/>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 26 May 2018 10:11:10 -0000

On Sat, May 26, 2018 at 10:59:50AM +0100, Johannes Lundberg wrote:
> Hi
> 
> The new AMD graphics drivers use floats in kernel space.
> Upstream Linux code has something like:
> kernel_fpu_begin();
> ...
> kernel_fpu_end();
> 
> Do we have similar functions to save/restore FPU registers?
Read fpu_kern(9).