From patchwork Sun Mar 6 11:55:43 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yaniv Gardi X-Patchwork-Id: 8512701 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B04579F38C for ; Sun, 6 Mar 2016 11:56:51 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C3B61200DB for ; Sun, 6 Mar 2016 11:56:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D846B2010E for ; Sun, 6 Mar 2016 11:56:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751524AbcCFL4e (ORCPT ); Sun, 6 Mar 2016 06:56:34 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:33319 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751298AbcCFL4T (ORCPT ); Sun, 6 Mar 2016 06:56:19 -0500 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 1E81560DC9; Sun, 6 Mar 2016 11:56:18 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 0E8F360DCC; Sun, 6 Mar 2016 11:56:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from lx-ygardi.mea.qualcomm.com (unknown [185.23.60.4]) (using TLSv1.1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: ygardi@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 5EA3860DC9; Sun, 6 Mar 2016 11:56:13 +0000 (UTC) From: Yaniv Gardi To: James.Bottomley@HansenPartnership.com Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, santoshsy@gmail.com, linux-scsi-owner@vger.kernel.org, ygardi@codeaurora.org, Subhash Jadavani , Vinayak Holikatti , "James E.J. Bottomley" , "Martin K. Petersen" Subject: [PATCH v6 02/17] scsi: ufs: avoid spurious UFS host controller interrupts Date: Sun, 6 Mar 2016 13:55:43 +0200 Message-Id: <1457265358-31635-3-git-send-email-ygardi@codeaurora.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1457265358-31635-1-git-send-email-ygardi@codeaurora.org> References: <1457265358-31635-1-git-send-email-ygardi@codeaurora.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When control reaches to Linux UFS driver during UFS boot mode, UFS host controller interrupt status/enable registers may have left over settings. In order to avoid any spurious interrupts due to these left overs, it's important to clear these interrupt status/enable registers before enabling UFS interrupt handling. Signed-off-by: Subhash Jadavani Signed-off-by: Yaniv Gardi --- drivers/scsi/ufs/ufshcd.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index a8e42df..de7280c 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -5837,6 +5837,21 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) init_waitqueue_head(&hba->dev_cmd.tag_wq); ufshcd_init_clk_gating(hba); + + /* + * In order to avoid any spurious interrupt immediately after + * registering UFS controller interrupt handler, clear any pending UFS + * interrupt status and disable all the UFS interrupts. + */ + ufshcd_writel(hba, ufshcd_readl(hba, REG_INTERRUPT_STATUS), + REG_INTERRUPT_STATUS); + ufshcd_writel(hba, 0, REG_INTERRUPT_ENABLE); + /* + * Make sure that UFS interrupts are disabled and any pending interrupt + * status is cleared before registering UFS interrupt handler. + */ + mb(); + /* IRQ registration */ err = devm_request_irq(dev, irq, ufshcd_intr, IRQF_SHARED, UFSHCD, hba); if (err) {