| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.14 191/228] dma: mv_xor: Flush descriptors before activating a channel | Date | Wed, 4 Jun 2014 16:23:40 -0700 |
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3.14-stable review patch. If anyone has any objections, please let me know.
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From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
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 <alior@marvell.com> Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- 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 @@ -191,12 +191,10 @@ static void mv_set_mode(struct mv_xor_ch 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)
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