From patchwork Wed Oct 31 15:57:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 10662869 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2F2CC14DE for ; Wed, 31 Oct 2018 15:58:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1F3D02AC58 for ; Wed, 31 Oct 2018 15:58:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 102D72ACA6; Wed, 31 Oct 2018 15:58:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 905542AC58 for ; Wed, 31 Oct 2018 15:58:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=WXK+kNyjnAzzoRfyTas22IYnH3yt+3jwpgWelB1hVvI=; b=DIn9otTlujgEP3 5ZYewr0V73dQaMMDzYJWw0/Jt2WugakdfN2l2A/jhCBSda+/d5RqnfFa4oAOlO+LRZ5JfCZpt19I3 mdg1rLN776AtB6qnCa3vGMkTlI8HGv68kM0Or81m/xgDpr/s8Ic0vIRL8vEEAdQF4H8pdwQh1nNv6 nJPjxE1ZlDUANiWOeIlcFdPWWVogeYsHIh1aUOyoWcWKd6CbZALcq/PcFKl04k16TNifCQCv4AgJe NVPuMj0mrMD9oOV5YFcb9zbTgZAMNXJRQ8SS/Ztgihfpm46rk+JhN84BarUY5mVx4G0ODJX/BdzJW 8bYlA50qfnrBOPwYf7YQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHssY-0002OQ-OW; Wed, 31 Oct 2018 15:57:58 +0000 Received: from muru.com ([72.249.23.125]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHssW-0002Nl-1v for linux-arm-kernel@lists.infradead.org; Wed, 31 Oct 2018 15:57:57 +0000 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id E9B2A8080; Wed, 31 Oct 2018 15:57:43 +0000 (UTC) From: Tony Lindgren To: Ulf Hansson Subject: [PATCH] mmc: core: Lower max_seg_size if too high for DMA Date: Wed, 31 Oct 2018 08:57:38 -0700 Message-Id: <20181031155738.18367-1-tony@atomide.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181031_085756_135602_F1F7D5F5 X-CRM114-Status: UNSURE ( 9.56 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-mmc@vger.kernel.org, Kishon Vijay Abraham I , Peter Ujfalusi , Russell King , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP With CONFIG_DMA_API_DEBUG_SG a device may produce the following warning: "DMA-API: mapping sg segment longer than device claims to support" We default to 64KiB if a DMA engine driver does not initialize dma_parms and call dma_set_max_seg_size(). This may be lower that what many MMC drivers do with mmc->max_seg_size = mmc->max_blk_size * mmc->max_blk_count. Let's do a sanity check for max_seg_size being higher than what DMA supports in mmc_add_host() and lower it as needed. Cc: Kishon Vijay Abraham I Cc: Peter Ujfalusi Cc: Russell King Reported-by: Russell King Signed-off-by: Tony Lindgren Reviewed-by: Peter Ujfalusi --- drivers/mmc/core/host.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -13,6 +13,7 @@ */ #include +#include #include #include #include @@ -415,6 +416,19 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) EXPORT_SYMBOL(mmc_alloc_host); +static void mmc_check_max_seg_size(struct mmc_host *host) +{ + unsigned int max_seg_size = dma_get_max_seg_size(mmc_dev(host)); + + if (host->max_seg_size <= max_seg_size) + return; + + dev_info(mmc_dev(host), "Lowering max_seg_size for DMA: %u vs %u\n", + host->max_seg_size, max_seg_size); + + host->max_seg_size = max_seg_size; +} + /** * mmc_add_host - initialise host hardware * @host: mmc host @@ -430,6 +444,8 @@ int mmc_add_host(struct mmc_host *host) WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) && !host->ops->enable_sdio_irq); + mmc_check_max_seg_size(host); + err = device_add(&host->class_dev); if (err) return err;