From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57276) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbXHY-0006dW-3n for qemu-devel@nongnu.org; Mon, 14 Sep 2015 13:11:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZbXHU-0005qy-TM for qemu-devel@nongnu.org; Mon, 14 Sep 2015 13:11:08 -0400 Received: from mail-qg0-x22e.google.com ([2607:f8b0:400d:c04::22e]:35132) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbXHU-0005qm-PD for qemu-devel@nongnu.org; Mon, 14 Sep 2015 13:11:04 -0400 Received: by qgt47 with SMTP id 47so120423965qgt.2 for ; Mon, 14 Sep 2015 10:11:04 -0700 (PDT) Sender: Richard Henderson References: <25f6c6b5-ea69-4f3c-9c4c-d17a8cebba45@email.android.com> <55F534FC.1030907@mail.uni-paderborn.de> From: Richard Henderson Message-ID: <55F6FFA5.6080305@twiddle.net> Date: Mon, 14 Sep 2015 10:11:01 -0700 MIME-Version: 1.0 In-Reply-To: <55F534FC.1030907@mail.uni-paderborn.de> Content-Type: text/plain; charset=utf-8 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: Bastian Koppelmann Cc: peter.maydell@linaro.org, Ethan Hunt , qemu-devel 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. In the meantime, testing of the multiply-accumulate instructions is hindered by the fact that linux-user can't read the MACHI and MACLO special registers. r~