From patchwork Mon Apr 27 13:59:50 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juergen Borleis X-Patchwork-Id: 6281041 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id DED8EBF4A7 for ; Mon, 27 Apr 2015 14:14:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8A21620421 for ; Mon, 27 Apr 2015 14:13:33 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6262B20145 for ; Mon, 27 Apr 2015 14:12:54 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YmjbU-0000aA-Ii; Mon, 27 Apr 2015 14:01:44 +0000 Received: from metis.ext.pengutronix.de ([2001:6f8:1178:4:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YmjaF-0007aJ-6l for linux-arm-kernel@lists.infradead.org; Mon, 27 Apr 2015 14:00:33 +0000 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.80) (envelope-from ) id 1YmjZn-0004u5-TJ; Mon, 27 Apr 2015 16:00:00 +0200 Received: from jbe by dude.hi.pengutronix.de with local (Exim 4.84) (envelope-from ) id 1YmjZm-0007LI-L4; Mon, 27 Apr 2015 15:59:58 +0200 From: Juergen Borleis To: linux-kernel@vger.kernel.org Subject: [PATCH 4/6] RTC/i.MX/DryIce: monitor a security violation at runtime Date: Mon, 27 Apr 2015 15:59:50 +0200 Message-Id: <1430143192-20667-5-git-send-email-jbe@pengutronix.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1430143192-20667-1-git-send-email-jbe@pengutronix.de> References: <1430143192-20667-1-git-send-email-jbe@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: jbe@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150427_070027_518142_1BE9B373 X-CRM114-Status: GOOD ( 14.00 ) X-Spam-Score: -0.0 (/) Cc: linux-arm-kernel@lists.infradead.org, Alessandro Zummo , Robert Schwebel , kernel@pengutronix.de, rtc-linux@googlegroups.com X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Maybe the unit enters the hardware related state at runtime and not at system boot time (after a power cycle). Signed-off-by: Juergen Borleis Signed-off-by: Robert Schwebel [rsc: got NDA clearance from Freescale] --- drivers/rtc/rtc-imxdi.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-imxdi.c b/drivers/rtc/rtc-imxdi.c index f0c8319..8890a62 100644 --- a/drivers/rtc/rtc-imxdi.c +++ b/drivers/rtc/rtc-imxdi.c @@ -665,6 +665,25 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) irqreturn_t rc = IRQ_NONE; dier = readl(imxdi->ioaddr + DIER); + dsr = readl(imxdi->ioaddr + DSR); + + /* handle the security violation event */ + if (dier & DIER_SVIE) { + if (dsr & DSR_SVF) { + /* + * Disable the interrupt when this kind of event has + * happened. + * There cannot be more than one event of this type, + * because it needs a complex state change + * including a main power cycle to get again out of + * this state. + */ + di_int_disable(imxdi, DIER_SVIE); + /* report the violation */ + di_report_tamper_info(imxdi, dsr); + rc = IRQ_HANDLED; + } + } /* handle write complete and write error cases */ if (dier & DIER_WCIE) { @@ -675,7 +694,6 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) return rc; /* DSR_WCF clears itself on DSR read */ - dsr = readl(imxdi->ioaddr + DSR); if (dsr & (DSR_WCF | DSR_WEF)) { /* mask the interrupt */ di_int_disable(imxdi, DIER_WCIE); @@ -691,7 +709,6 @@ static irqreturn_t dryice_norm_irq(int irq, void *dev_id) /* handle the alarm case */ if (dier & DIER_CAIE) { /* DSR_WCF clears itself on DSR read */ - dsr = readl(imxdi->ioaddr + DSR); if (dsr & DSR_CAF) { /* mask the interrupt */ di_int_disable(imxdi, DIER_CAIE);