From patchwork Tue Jun 4 16:55:33 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 248771 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 29B3F2C00A4 for ; Wed, 5 Jun 2013 03:03:08 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UjudO-0000ef-8e; Tue, 04 Jun 2013 17:02:58 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Ujud3-0000YZ-OF for kernel-team@lists.ubuntu.com; Tue, 04 Jun 2013 17:02:37 +0000 Received: from c-67-160-231-42.hsd1.ca.comcast.net ([67.160.231.42] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1UjuXt-0003F8-4t; Tue, 04 Jun 2013 16:57:17 +0000 Received: from kamal by fourier with local (Exim 4.80) (envelope-from ) id 1UjuXq-0002tx-Sp; Tue, 04 Jun 2013 09:57:14 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 49/75] rapidio/tsi721: fix bug in MSI interrupt handling Date: Tue, 4 Jun 2013 09:55:33 -0700 Message-Id: <1370364959-9475-50-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1370364959-9475-1-git-send-email-kamal@canonical.com> References: <1370364959-9475-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Cc: Kamal Mostafa , Alexandre Bounine , Matt Porter , Linus Torvalds , Andrew Morton X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.8.13.2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Bounine commit 1ccc819da6fda9bee10ab8b72e9adbb5ad3e4959 upstream. Fix bug in MSI interrupt handling which causes loss of event notifications. Typical indication of lost MSI interrupts are stalled message and doorbell transfers between RapidIO endpoints. To avoid loss of MSI interrupts all interrupts from the device must be disabled on entering the interrupt handler routine and re-enabled when exiting it. Re-enabling device interrupts will trigger new MSI message(s) if Tsi721 registered new events since entering interrupt handler routine. This patch is applicable to kernel versions starting from v3.2. Signed-off-by: Alexandre Bounine Cc: Matt Porter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Kamal Mostafa --- drivers/rapidio/devices/tsi721.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c index 6faba40..a8b2c23 100644 --- a/drivers/rapidio/devices/tsi721.c +++ b/drivers/rapidio/devices/tsi721.c @@ -471,6 +471,10 @@ static irqreturn_t tsi721_irqhandler(int irq, void *ptr) u32 intval; u32 ch_inte; + /* For MSI mode disable all device-level interrupts */ + if (priv->flags & TSI721_USING_MSI) + iowrite32(0, priv->regs + TSI721_DEV_INTE); + dev_int = ioread32(priv->regs + TSI721_DEV_INT); if (!dev_int) return IRQ_NONE; @@ -560,6 +564,14 @@ static irqreturn_t tsi721_irqhandler(int irq, void *ptr) } } #endif + + /* For MSI mode re-enable device-level interrupts */ + if (priv->flags & TSI721_USING_MSI) { + dev_int = TSI721_DEV_INT_SR2PC_CH | TSI721_DEV_INT_SRIO | + TSI721_DEV_INT_SMSG_CH | TSI721_DEV_INT_BDMA_CH; + iowrite32(dev_int, priv->regs + TSI721_DEV_INTE); + } + return IRQ_HANDLED; }