From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753602AbaFGBrU (ORCPT ); Fri, 6 Jun 2014 21:47:20 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35956 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752499AbaFGBXg (ORCPT ); Fri, 6 Jun 2014 21:23:36 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Lior Amsalem" , "Ezequiel Garcia" , "Dan Williams" Date: Sat, 07 Jun 2014 02:26:29 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 84/92] dma: mv_xor: Flush descriptors before activating a channel In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.60-rc1 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 [bwh: Backported to 3.2: it was using __raw_readl() and __raw_writel() which are just as wrong] Signed-off-by: Ben Hutchings --- drivers/dma/mv_xor.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/drivers/dma/mv_xor.c +++ b/drivers/dma/mv_xor.c @@ -218,12 +218,10 @@ static void mv_set_mode(struct mv_xor_ch static void mv_chan_activate(struct mv_xor_chan *chan) { - u32 activation; - dev_dbg(chan->device->common.dev, " activate chan.\n"); - activation = __raw_readl(XOR_ACTIVATION(chan)); - activation |= 0x1; - __raw_writel(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)