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: 5038871 Return-Path: X-Original-To: patchwork-linux-mmc@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 8273CC11AB for ; Mon, 6 Oct 2014 17:53:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AEDB92014A for ; Mon, 6 Oct 2014 17:53:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D77692011D for ; Mon, 6 Oct 2014 17:53:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752281AbaJFRx4 (ORCPT ); Mon, 6 Oct 2014 13:53:56 -0400 Received: from mail-ig0-f202.google.com ([209.85.213.202]:53374 "EHLO mail-ig0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752080AbaJFRx4 (ORCPT ); Mon, 6 Oct 2014 13:53:56 -0400 Received: by mail-ig0-f202.google.com with SMTP id r10so590014igi.1 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=Y6NpyQQF02Gdde4KERulposJM5nhICY4veamAixoThqr3ju+givDQPpwGfAxKNaANt fn9N1CBpvcNgXk3lNdiGgNfrmlVwKPQG9RVk5vQpYQ+uwYNZqMJcPiE8vUmnv3xovz0V RcIK2APjU5ij2BvmsvlYk/65H8rM2TXi6MCQjLXtQQIL8562q86EO8r7Fw5WDAyWOfjJ 23vHbfZh1E0L4FcImVxgSO8sbd7wbnm5NrYaqFX+zcN1ofcMbr1xSVwLoknuhUiSetcF cjyRHTAXIw71y3nn8HR6eHrCQ7wSwoLKI3vJTKdJDh03/4ICVigsU1rB0KSD/su23vFU GsEA== X-Gm-Message-State: ALoCoQnPUjS/j3wxQX3Auci+TXhk8Rurk6Mm2woa89v9TTGBJK+DKYdiv8NqNThVnLZDGyyqgMAn 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 Cc: Heiko Stuebner , Seungwon Jeon , Jaehoon Chung , Ulf Hansson , dianders@chromium.org, eddie.cai@rock-chips.com, addy.ke@rock-chips.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sonny Rao 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 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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;