From patchwork Fri Jan 27 15:32:13 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 92677 Delivered-To: patch@linaro.org Received: by 10.140.20.99 with SMTP id 90csp291934qgi; Fri, 27 Jan 2017 07:39:36 -0800 (PST) X-Received: by 10.55.221.79 with SMTP id n76mr8308190qki.276.1485531576672; Fri, 27 Jan 2017 07:39:36 -0800 (PST) Return-Path: Received: from lists.gnu.org (lists.gnu.org. [2001:4830:134:3::11]) by mx.google.com with ESMTPS id a19si3780120qtc.79.2017.01.27.07.39.36 for (version=TLS1 cipher=AES128-SHA bits=128/128); Fri, 27 Jan 2017 07:39:36 -0800 (PST) Received-SPF: pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) client-ip=2001:4830:134:3::11; Authentication-Results: mx.google.com; spf=pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 2001:4830:134:3::11 as permitted sender) smtp.mailfrom=qemu-devel-bounces+patch=linaro.org@nongnu.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: from localhost ([::1]:46295 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cX8cg-0000TD-4R for patch@linaro.org; Fri, 27 Jan 2017 10:39:34 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59607) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cX8Vr-000124-F9 for qemu-devel@nongnu.org; Fri, 27 Jan 2017 10:32:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cX8Vq-00057S-L1 for qemu-devel@nongnu.org; Fri, 27 Jan 2017 10:32:31 -0500 Received: from orth.archaic.org.uk ([2001:8b0:1d0::2]:48310) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cX8Vq-000541-Ex for qemu-devel@nongnu.org; Fri, 27 Jan 2017 10:32:30 -0500 Received: from pm215 by orth.archaic.org.uk with local (Exim 4.84_2) (envelope-from ) id 1cX8Vm-0003RT-V9 for qemu-devel@nongnu.org; Fri, 27 Jan 2017 15:32:26 +0000 From: Peter Maydell To: qemu-devel@nongnu.org Date: Fri, 27 Jan 2017 15:32:13 +0000 Message-Id: <1485531137-2362-19-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1485531137-2362-1-git-send-email-peter.maydell@linaro.org> References: <1485531137-2362-1-git-send-email-peter.maydell@linaro.org> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2001:8b0:1d0::2 Subject: [Qemu-devel] [PULL 18/22] armv7m: R14 should reset to 0xffffffff X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patch=linaro.org@nongnu.org Sender: "Qemu-devel" For M profile (unlike A profile) the reset value of R14 is specified as 0xffffffff. (The rationale is that this is an illegal exception return value, so if guest code tries to return to it it will result in a helpful exception.) Registers r0 to r12 and the flags are architecturally UNKNOWN on reset, so we leave those at zero. Signed-off-by: Peter Maydell Reviewed-by: Alex Bennée Message-id: 1485285380-10565-11-git-send-email-peter.maydell@linaro.org --- target/arm/cpu.c | 3 +++ 1 file changed, 3 insertions(+) -- 2.7.4 diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 0814f73..e9f10f7 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -196,6 +196,9 @@ static void arm_cpu_reset(CPUState *s) */ env->v7m.ccr = R_V7M_CCR_STKALIGN_MASK; + /* Unlike A/R profile, M profile defines the reset LR value */ + env->regs[14] = 0xffffffff; + /* Load the initial SP and PC from the vector table at address 0 */ rom = rom_ptr(0); if (rom) {