diff options
| author | Lars-Peter Clausen <lars@metafoo.de> | 2014-01-11 20:08:38 +0100 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2014-01-20 13:50:49 +0530 |
| commit | 04abf5daf7df852566e5a4782d5954daa40e2542 (patch) | |
| tree | 8bee95188e65e2264633a8ec9ee8bb8bc898913f /drivers/dma | |
| parent | ba07d812f58c0ec65fff981a085529ed88965d23 (diff) | |
dma: pl330: Differentiate between submitted and issued descriptors
The pl330 dmaengine driver currently does not differentiate between submitted
and issued descriptors. It won't start transferring a newly submitted
descriptor until issue_pending() is called, but only if it is idle. If it is
active and a new descriptor is submitted before it goes idle it will happily
start the newly submitted descriptor once all earlier submitted descriptors have
been completed. This is not a 100% correct with regards to the dmaengine
interface semantics. A descriptor is not supposed to be started until the next
issue_pending() call after the descriptor has been submitted. This patch adds a
second per channel list that keeps track of the submitted descriptors. Once
issue_pending() is called the submitted descriptors are moved to the working
list and only descriptors on the working list are started.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/pl330.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 7adaf3abffba..8e018a221f19 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -543,7 +543,9 @@ struct dma_pl330_chan { /* DMA-Engine Channel */ struct dma_chan chan; - /* List of to be xfered descriptors */ + /* List of submitted descriptors */ + struct list_head submitted_list; + /* List of issued descriptors */ struct list_head work_list; /* List of completed descriptors */ struct list_head completed_list; @@ -2388,6 +2390,11 @@ static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned pl330_chan_ctrl(pch->pl330_chid, PL330_OP_FLUSH); /* Mark all desc done */ + list_for_each_entry(desc, &pch->submitted_list, node) { + desc->status = FREE; + dma_cookie_complete(&desc->txd); + } + list_for_each_entry(desc, &pch->work_list , node) { desc->status = FREE; dma_cookie_complete(&desc->txd); @@ -2398,6 +2405,7 @@ static int pl330_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned dma_cookie_complete(&desc->txd); } + list_splice_tail_init(&pch->submitted_list, &pdmac->desc_pool); list_splice_tail_init(&pch->work_list, &pdmac->desc_pool); list_splice_tail_init(&pch->completed_list, &pdmac->desc_pool); spin_unlock_irqrestore(&pch->lock, flags); @@ -2456,7 +2464,14 @@ pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie, static void pl330_issue_pending(struct dma_chan *chan) { - pl330_tasklet((unsigned long) to_pchan(chan)); + struct dma_pl330_chan *pch = to_pchan(chan); + unsigned long flags; + + spin_lock_irqsave(&pch->lock, flags); + list_splice_tail_init(&pch->submitted_list, &pch->work_list); + spin_unlock_irqrestore(&pch->lock, flags); + + pl330_tasklet((unsigned long)pch); } /* @@ -2483,11 +2498,11 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx) dma_cookie_assign(&desc->txd); - list_move_tail(&desc->node, &pch->work_list); + list_move_tail(&desc->node, &pch->submitted_list); } cookie = dma_cookie_assign(&last->txd); - list_add_tail(&last->node, &pch->work_list); + list_add_tail(&last->node, &pch->submitted_list); spin_unlock_irqrestore(&pch->lock, flags); return cookie; @@ -2979,6 +2994,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) else pch->chan.private = adev->dev.of_node; + INIT_LIST_HEAD(&pch->submitted_list); INIT_LIST_HEAD(&pch->work_list); INIT_LIST_HEAD(&pch->completed_list); spin_lock_init(&pch->lock); |