From patchwork Mon Oct 6 17:53:40 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sonny Rao X-Patchwork-Id: 5038891 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 [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A39E5C11AB for ; Mon, 6 Oct 2014 17:56:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B470C20122 for ; Mon, 6 Oct 2014 17:56:32 +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 E04E82011D for ; Mon, 6 Oct 2014 17:56:31 +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 1XbCUG-0002w9-1Q; Mon, 06 Oct 2014 17:54:20 +0000 Received: from mail-ig0-f202.google.com ([209.85.213.202]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XbCUD-0002rp-J0 for linux-arm-kernel@lists.infradead.org; Mon, 06 Oct 2014 17:54:18 +0000 Received: by mail-ig0-f202.google.com with SMTP id r10so587989igi.5 for ; Mon, 06 Oct 2014 10:53:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=v8ITkm84c367yhpfGmO11JG5uNKsd7XoXO+gWQ+SJug=; b=Ho8gSevY026PxXXywIsVuYgbABYTh1TnTiQOgHX6PLDHQhMXJKxZcPvRhJd9z2HHjh ExPDrFYGU/nmAdcipVDiCa837MedQLvhHTf+vWahhxAebnkiLu2rFaQ/hYJIZ1GtMw0C a93n6cDHZsM7qCyqzvkjp2lT3eqIShEgw+Diggo8X8DNiwo9KhBmjHOWslNI1oiS3Hc+ yjaK32Gi+uB3wQbtwvTuJcGBxoeX47Nuso8UCMI64ViO+ef3ZxVZqeJLxz9O5DLaYDja eJtnijmm6Z8N1m+AFhEBYXb+MlmVW0mBUZ9JZkDlRZHuoVp7CnRmncUfgEDbAaANumji yNJw== X-Gm-Message-State: ALoCoQkbqNfsFSK4XUpUc4AaYYkttkZzR7cAvzUx7mJQAiMyphc7g4Db7rkJkzmT2NRAiZ66lr/m X-Received: by 10.182.251.135 with SMTP id zk7mr18142580obc.14.1412618035438; Mon, 06 Oct 2014 10:53:55 -0700 (PDT) Received: from corpmail-nozzle1-2.hot.corp.google.com ([100.108.1.103]) by gmr-mx.google.com with ESMTPS id t28si728568yhb.4.2014.10.06.10.53.54 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 06 Oct 2014 10:53:55 -0700 (PDT) Received: from sonnyrao.mtv.corp.google.com ([172.22.162.1]) by corpmail-nozzle1-2.hot.corp.google.com with ESMTP id hCyMtELT.1; Mon, 06 Oct 2014 10:53:55 -0700 Received: by sonnyrao.mtv.corp.google.com (Postfix, from userid 129445) id 1F4E6A0C7A; Mon, 6 Oct 2014 10:53:54 -0700 (PDT) From: Sonny Rao To: linux-mmc@vger.kernel.org Subject: [PATCH] mmc: dw_mmc: Reset DMA before enabling IDMAC Date: Mon, 6 Oct 2014 10:53:40 -0700 Message-Id: <1412618020-22278-1-git-send-email-sonnyrao@chromium.org> X-Mailer: git-send-email 2.1.0.rc2.206.gedb03e5 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141006_105417_663001_CC6A0689 X-CRM114-Status: GOOD ( 12.61 ) X-Spam-Score: -0.7 (/) Cc: Ulf Hansson , Heiko Stuebner , addy.ke@rock-chips.com, Seungwon Jeon , dianders@chromium.org, linux-kernel@vger.kernel.org, Jaehoon Chung , eddie.cai@rock-chips.com, Sonny Rao , linux-arm-kernel@lists.infradead.org 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, RCVD_IN_DNSWL_NONE, T_RP_MATCHES_RCVD, 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 We've already got a reset of DMA after it's done. Add one before we start DMA too. This fixes a data corruption on Rockchip SoCs which will get bad data when doing a DMA transfer after doing a PIO transfer. We tested this on an Exynos 5800 with HS200 and didn't notice any difference in sequential read throughput. Signed-off-by: Sonny Rao Signed-off-by: Doug Anderson Reviewed-by: Doug Anderson Tested-by: Doug Anderson Acked-by: Jaehoon Chung --- drivers/mmc/host/dw_mmc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 69f0cc6..2b5401e 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -83,6 +83,7 @@ struct idmac_desc { #endif /* CONFIG_MMC_DW_IDMAC */ static bool dw_mci_reset(struct dw_mci *host); +static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset); #if defined(CONFIG_DEBUG_FS) static int dw_mci_req_show(struct seq_file *s, void *v) @@ -448,6 +449,9 @@ static void dw_mci_idmac_start_dma(struct dw_mci *host, unsigned int sg_len) dw_mci_translate_sglist(host, host->data, sg_len); + /* Make sure to reset DMA in case we did PIO before this */ + dw_mci_ctrl_reset(host, SDMMC_CTRL_DMA_RESET); + /* Select IDMAC interface */ temp = mci_readl(host, CTRL); temp |= SDMMC_CTRL_USE_IDMAC;