lkml.org 
[lkml]   [2022]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 1/2] dmaengine: ptdma: fix concurrency issue with multiple dma transfer
Date
From: Sanjay R Mehta <sanju.mehta@amd.com>

The command should be submitted only if the engine is idle,
for this, the next available descriptor is checked and set the flag
to false in case the descriptor is non-empty.

Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
---
drivers/dma/ptdma/ptdma-dmaengine.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/ptdma/ptdma-dmaengine.c b/drivers/dma/ptdma/ptdma-dmaengine.c
index c9e52f6..e38dca4 100644
--- a/drivers/dma/ptdma/ptdma-dmaengine.c
+++ b/drivers/dma/ptdma/ptdma-dmaengine.c
@@ -233,9 +233,14 @@ static void pt_issue_pending(struct dma_chan *dma_chan)
struct pt_dma_chan *chan = to_pt_chan(dma_chan);
struct pt_dma_desc *desc;
unsigned long flags;
+ bool engine_is_idle = true;

spin_lock_irqsave(&chan->vc.lock, flags);

+ desc = pt_next_dma_desc(chan);
+ if (desc)
+ engine_is_idle = false;
+
vchan_issue_pending(&chan->vc);

desc = pt_next_dma_desc(chan);
@@ -243,7 +248,7 @@ static void pt_issue_pending(struct dma_chan *dma_chan)
spin_unlock_irqrestore(&chan->vc.lock, flags);

/* If there was nothing active, start processing */
- if (desc)
+ if (engine_is_idle)
pt_cmd_callback(desc, 0);
}

--
2.7.4
\
 
 \ /
  Last update: 2022-02-02 16:16    [W:0.045 / U:0.352 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site