From: Ezequiel Garcia Date: Wed, 21 May 2014 21:02:35 +0000 (-0700) Subject: dma: mv_xor: Flush descriptors before activating a channel X-Git-Tag: firefly_0821_release~176^2~3873^2~1 X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=5a9a55bf9157d3490b0c8c4c81d4708602c26e07;p=firefly-linux-kernel-4.4.55.git dma: mv_xor: Flush descriptors before activating a channel 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. Cc: Signed-off-by: Lior Amsalem Signed-off-by: Ezequiel Garcia Signed-off-by: Dan Williams --- diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c index 766b68ed505c..394cbc5c93e3 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)