From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966935AbaFQWYf (ORCPT ); Tue, 17 Jun 2014 18:24:35 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:54333 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966532AbaFQVuO (ORCPT ); Tue, 17 Jun 2014 17:50:14 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Lior Amsalem , Ezequiel Garcia , Dan Williams , Kamal Mostafa Subject: [PATCH 3.13 159/212] dma: mv_xor: Flush descriptors before activating a channel Date: Tue, 17 Jun 2014 14:44:13 -0700 Message-Id: <1403041506-13646-160-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1403041506-13646-1-git-send-email-kamal@canonical.com> References: <1403041506-13646-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Ezequiel Garcia commit 5a9a55bf9157d3490b0c8c4c81d4708602c26e07 upstream. We need to use writel() instead of writel_relaxed() when starting a channel, to ensure all the descriptors have been flushed before the activation. While at it, remove the unneeded read-modify-write and make the code simpler. Signed-off-by: Lior Amsalem Signed-off-by: Ezequiel Garcia Signed-off-by: Dan Williams Signed-off-by: Kamal Mostafa --- drivers/dma/mv_xor.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c index 53fb0c8..29c8a06 100644 --- a/drivers/dma/mv_xor.c +++ b/drivers/dma/mv_xor.c @@ -191,12 +191,10 @@ static void mv_set_mode(struct mv_xor_chan *chan, static void mv_chan_activate(struct mv_xor_chan *chan) { - u32 activation; - dev_dbg(mv_chan_to_devp(chan), " activate chan.\n"); - activation = readl_relaxed(XOR_ACTIVATION(chan)); - activation |= 0x1; - writel_relaxed(activation, XOR_ACTIVATION(chan)); + + /* writel ensures all descriptors are flushed before activation */ + writel(BIT(0), XOR_ACTIVATION(chan)); } static char mv_chan_is_busy(struct mv_xor_chan *chan) -- 1.9.1