From patchwork Wed Dec 11 21:13:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Kubascik X-Patchwork-Id: 11286433 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E040B14B7 for ; Wed, 11 Dec 2019 21:14:25 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C7446222C4 for ; Wed, 11 Dec 2019 21:14:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C7446222C4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=dornerworks.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1if9Ie-0007SM-HQ; Wed, 11 Dec 2019 21:13:36 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1if9Id-0007S8-1B for xen-devel@lists.xenproject.org; Wed, 11 Dec 2019 21:13:35 +0000 X-Inumbo-ID: 133acc28-1c5b-11ea-b6f1-bc764e2007e4 Received: from webmail.dornerworks.com (unknown [12.207.209.150]) by us1-rack-iad1.inumbo.com (Halon) with ESMTP id 133acc28-1c5b-11ea-b6f1-bc764e2007e4; Wed, 11 Dec 2019 21:13:28 +0000 (UTC) From: Jeff Kubascik To: Date: Wed, 11 Dec 2019 16:13:02 -0500 Message-ID: <20191211211302.117395-3-jeff.kubascik@dornerworks.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191211211302.117395-1-jeff.kubascik@dornerworks.com> References: <20191211211302.117395-1-jeff.kubascik@dornerworks.com> MIME-Version: 1.0 X-Originating-IP: [172.27.13.171] X-ClientProxiedBy: Mcbain.dw.local (172.27.1.45) To Mcbain.dw.local (172.27.1.45) X-spam-status: No, score=-2.9 required=3.5 tests=ALL_TRUSTED, BAYES_00, MAILSHELL_SCORE_0_4 X-Spam-Flag: NO Subject: [Xen-devel] [PATCH v3 2/2] xen/arm: sign extend writes to TimerValue X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Stewart Hildebrand , Volodymyr Babchuk , Stefano Stabellini , Julien Grall Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Per the ARMv8 Reference Manual (ARM DDI 0487E.a), section D11.2.4 specifies that the values in the TimerValue view of the timers are signed in standard two's complement form. When writing to the TimerValue register, it should be signed extended as described by the equation CompareValue = (Counter[63:0] + SignExtend(TimerValue))[63:0] Signed-off-by: Jeff Kubascik --- xen/arch/arm/vtimer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/xen/arch/arm/vtimer.c b/xen/arch/arm/vtimer.c index 21b98ec20a..872181d9b6 100644 --- a/xen/arch/arm/vtimer.c +++ b/xen/arch/arm/vtimer.c @@ -211,7 +211,7 @@ static bool vtimer_cntp_tval(struct cpu_user_regs *regs, uint32_t *r, } else { - v->arch.phys_timer.cval = cntpct + *r; + v->arch.phys_timer.cval = cntpct + (uint64_t)(int32_t)*r; if ( v->arch.phys_timer.ctl & CNTx_CTL_ENABLE ) { v->arch.phys_timer.ctl &= ~CNTx_CTL_PENDING;