From patchwork Thu May 29 08:28:03 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Fenkart X-Patchwork-Id: 4263081 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 603369F1E7 for ; Thu, 29 May 2014 08:29:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 68B26201C7 for ; Thu, 29 May 2014 08:29:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87ED3202DD for ; Thu, 29 May 2014 08:29:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932797AbaE2I3W (ORCPT ); Thu, 29 May 2014 04:29:22 -0400 Received: from mail-oa0-f54.google.com ([209.85.219.54]:41380 "EHLO mail-oa0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932431AbaE2I3U (ORCPT ); Thu, 29 May 2014 04:29:20 -0400 Received: by mail-oa0-f54.google.com with SMTP id j17so3625oag.41 for ; Thu, 29 May 2014 01:29:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=wv1ghIfjbqgPBzjwXcIsWpGZBg3vyhdE+JZWMizt4iU=; b=VcW/eM0KGGmw4xDKv4BL+vBZsiAb/oMDypUz3TlgxigIOTdywMou2Xopls/unSuGYB gKJA/ifCDBE9PLdYRwlqiLqIwAa5fd5IWQvH9IudTNqqaeq89+bYg8T+o1ur9dIX2ZG0 KEqbF7Z7RjTdeALYlUrDgN4DnVScZ5qcRA3FD0Y5wMjrYMUAaYCG5T2h45fwOi6Zq1Y8 gtM16IjcU6gvK19PNS04H1I+Y5Mk9uYvzyysiCnPincGZla4yFr7ve34adEJTdS4UxZQ AnnX1n1nDZFHc2bcTYyGDcAJk+wckgbX3wJ0Q2uN9yzoahBxmLTZiqrGhbL/rQVGVewn EzIA== X-Received: by 10.182.200.131 with SMTP id js3mr6559987obc.0.1401352159810; Thu, 29 May 2014 01:29:19 -0700 (PDT) Received: from localhost (ip-89-176-190-91.net.upcbroadband.cz. [89.176.190.91]) by mx.google.com with ESMTPSA id ny5sm39168894obb.21.2014.05.29.01.29.16 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Thu, 29 May 2014 01:29:19 -0700 (PDT) From: Andreas Fenkart To: Tony Lindgren Cc: Chris Ball , Grant Likely , Felipe Balbi , Balaji T K , Andreas Mueller , Sebastian Reichel , zonque@gmail.com, galak@codeaurora.org, linux-doc@vger.kernel.org, linux-mmc@vger.kernel.org, linux-omap@vger.kernel.org, Andreas Fenkart Subject: [PATCH v14 4/6] mmc: omap_hsmmc: abort runtime suspend if pending sdio irq detected Date: Thu, 29 May 2014 10:28:03 +0200 Message-Id: <1401352085-22781-5-git-send-email-afenkart@gmail.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1401352085-22781-1-git-send-email-afenkart@gmail.com> References: <1401352085-22781-1-git-send-email-afenkart@gmail.com> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY 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 On multicores, an sdio irq handler could be running in parallel to runtime suspend. In the worst case it could be waiting for the spinlock held by the runtime suspend. When runtime suspend is complete and the functional clock (fclk) turned off, the irq handler will continue and cause a SIGBUS on the first register access. Acked-by: Balaji T K Signed-off-by: Andreas Fenkart diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index b8be438..2408ec9 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -107,6 +107,9 @@ #define SRD (1 << 26) #define SOFTRESET (1 << 1) +/* PSTATE */ +#define DLEV_DAT(x) (1 << (20 + (x))) + /* Interrupt masks for IE and ISE register */ #define CC_EN (1 << 0) #define TC_EN (1 << 1) @@ -2397,6 +2400,7 @@ static int omap_hsmmc_runtime_suspend(struct device *dev) { struct omap_hsmmc_host *host; unsigned long flags; + int ret = 0; host = platform_get_drvdata(to_platform_device(dev)); omap_hsmmc_context_save(host); @@ -2408,14 +2412,29 @@ static int omap_hsmmc_runtime_suspend(struct device *dev) /* disable sdio irq handling to prevent race */ OMAP_HSMMC_WRITE(host->base, ISE, 0); OMAP_HSMMC_WRITE(host->base, IE, 0); - OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR); + + if (!(OMAP_HSMMC_READ(host->base, PSTATE) & DLEV_DAT(1))) { + /* + * dat1 line low, pending sdio irq + * race condition: possible irq handler running on + * multi-core, abort + */ + dev_dbg(dev, "pending sdio irq, abort suspend\n"); + OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR); + OMAP_HSMMC_WRITE(host->base, ISE, CIRQ_EN); + OMAP_HSMMC_WRITE(host->base, IE, CIRQ_EN); + pm_runtime_mark_last_busy(dev); + ret = -EBUSY; + goto abort; + } WARN_ON(host->flags & HSMMC_WAKE_IRQ_ENABLED); enable_irq(host->wake_irq); host->flags |= HSMMC_WAKE_IRQ_ENABLED; } +abort: spin_unlock_irqrestore(&host->irq_lock, flags); - return 0; + return ret; } static int omap_hsmmc_runtime_resume(struct device *dev)