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@xxxxxxxxxxx>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@xxxxxxxxxxxxxxxxxx>
---
This fix applies cleanly since commit:
5733c38 mv_xor: use {readl, writel}_relaxed instead of __raw_{readl, writel}
Given the fix is applicable since the introduction of the driver,
in v2.6.27, it should be marked accordingly. I can provide a backport
in due time.
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 766b68e..394cbc5 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
--
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