From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36051) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbkZu-0004ma-57 for qemu-devel@nongnu.org; Tue, 15 Sep 2015 03:22:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZbkZr-0007wP-2X for qemu-devel@nongnu.org; Tue, 15 Sep 2015 03:22:58 -0400 Received: from mail.uni-paderborn.de ([131.234.142.9]:49331) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbkZq-0007uF-SR for qemu-devel@nongnu.org; Tue, 15 Sep 2015 03:22:55 -0400 References: <25f6c6b5-ea69-4f3c-9c4c-d17a8cebba45@email.android.com> <55F534FC.1030907@mail.uni-paderborn.de> <55F6FFA5.6080305@twiddle.net> From: Bastian Koppelmann Message-ID: <55F7C748.3030007@mail.uni-paderborn.de> Date: Tue, 15 Sep 2015 09:22:48 +0200 MIME-Version: 1.0 In-Reply-To: <55F6FFA5.6080305@twiddle.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 12/17] target-openrisc: Enable m[tf]spr from user mode List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: peter.maydell@linaro.org, Ethan Hunt , qemu-devel On 09/14/2015 07:11 PM, Richard Henderson wrote: > On 09/13/2015 01:34 AM, Bastian Koppelmann wrote: >> Looking at the article, user mode seems to be optional, so I'm not against it, >> but it does look weird. How does ork1sim do it? > It's haphazard. There are checks for supervisor in the l_mtspr and l_mfspr > insns, but not other uses of the sprs, such as l_rfe. How about we make the optional user mode a feature bit? This way we are closer to ork1sim, but don't have the problem that testing is hindered. Cheers, Bastian