From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1LAsbL-0001H8-8I
	for qemu-devel@nongnu.org; Thu, 11 Dec 2008 15:57:39 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1LAsbK-0001Ga-Id
	for qemu-devel@nongnu.org; Thu, 11 Dec 2008 15:57:38 -0500
Received: from [199.232.76.173] (port=36290 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1LAsbK-0001GT-Cz
	for qemu-devel@nongnu.org; Thu, 11 Dec 2008 15:57:38 -0500
Received: from fg-out-1718.google.com ([72.14.220.152]:22223)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <laurent.desnogues@gmail.com>) id 1LAsbJ-0006Ii-PR
	for qemu-devel@nongnu.org; Thu, 11 Dec 2008 15:57:38 -0500
Received: by fg-out-1718.google.com with SMTP id l26so608318fgb.8
	for <qemu-devel@nongnu.org>; Thu, 11 Dec 2008 12:57:35 -0800 (PST)
Message-ID: <761ea48b0812111257n3c8713a3r13224f3e9ace20b@mail.gmail.com>
Date: Thu, 11 Dec 2008 21:57:34 +0100
From: "Laurent Desnogues" <laurent.desnogues@gmail.com>
Subject: Re: [Qemu-devel] Re: SH4: Implement FD bit
In-Reply-To: <1229026342.3898.24.camel@cocoduo.atr>
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
References: <200812012022.02276.vladimir@codesourcery.com>
	<20081207224734.GD3591@volta.aurel32.net>
	<E1LA5ZL-0002xp-99@zigzag.lvk.cs.msu.su>
	<1229026342.3898.24.camel@cocoduo.atr>
Reply-To: qemu-devel@nongnu.org
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: qemu-devel@nongnu.org

On Thu, Dec 11, 2008 at 9:12 PM, Lionel Landwerlin
<lionel.landwerlin@openwide.fr> wrote:
> According to you, should the FD bit be "up" by default in user mode emulation ?
>
> By putting the FD bit "down" in cpu_sh4_reset(target-sh4/translate.c), I'm able to restore initial
> behavior of user mode emulation (that means, qemu does not exits very early before libc initialization
> (see the traces before)).
>
> Maybe putting down the FD bit should be done in a user mode part only... I'm wondering...

It doesn't look unacceptable to have some features enabled
in user mode that are not set at reset, since typically the OS
will enable these features either as its boot process or
depending on a process requirements.

BTW ins't the need for floating-point instructions contained
in some ELF SH4 flags?


Laurent