diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2016-02-10 15:59:42 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-03-03 15:07:24 -0800 |
| commit | 556dfd8dae7d66b35121ffa8198465e55a34d64d (patch) | |
| tree | 7bd94d081121ad4246855dd1df302b5522b2dfaf /drivers | |
| parent | f4fa3d6f9e84d5009d78c732a0a81251b8bfe0b4 (diff) | |
dmaengine: dw: disable BLOCK IRQs for non-cyclic xfer
commit ee1cdcdae59563535485a5f56ee72c894ab7d7ad upstream.
The commit 2895b2cad6e7 ("dmaengine: dw: fix cyclic transfer callbacks")
re-enabled BLOCK interrupts with regard to make cyclic transfers work. However,
this change becomes a regression for non-cyclic transfers as interrupt counters
under stress test had been grown enormously (approximately per 4-5 bytes in the
UART loop back test).
Taking into consideration above enable BLOCK interrupts if and only if channel
is programmed to perform cyclic transfer.
Fixes: 2895b2cad6e7 ("dmaengine: dw: fix cyclic transfer callbacks")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mans Rullgard <mans@mansr.com>
Tested-by: Mans Rullgard <mans@mansr.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/dma/dw/core.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index b92662722404..4f099ea29f83 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -156,7 +156,6 @@ static void dwc_initialize(struct dw_dma_chan *dwc) /* Enable interrupts */ channel_set_bit(dw, MASK.XFER, dwc->mask); - channel_set_bit(dw, MASK.BLOCK, dwc->mask); channel_set_bit(dw, MASK.ERROR, dwc->mask); dwc->initialized = true; @@ -588,6 +587,9 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc, spin_unlock_irqrestore(&dwc->lock, flags); } + + /* Re-enable interrupts */ + channel_set_bit(dw, MASK.BLOCK, dwc->mask); } /* ------------------------------------------------------------------------- */ @@ -618,11 +620,8 @@ static void dw_dma_tasklet(unsigned long data) dwc_scan_descriptors(dw, dwc); } - /* - * Re-enable interrupts. - */ + /* Re-enable interrupts */ channel_set_bit(dw, MASK.XFER, dw->all_chan_mask); - channel_set_bit(dw, MASK.BLOCK, dw->all_chan_mask); channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask); } @@ -1256,6 +1255,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan) int dw_dma_cyclic_start(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); + struct dw_dma *dw = to_dw_dma(chan->device); unsigned long flags; if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) { @@ -1264,7 +1264,12 @@ int dw_dma_cyclic_start(struct dma_chan *chan) } spin_lock_irqsave(&dwc->lock, flags); + + /* Enable interrupts to perform cyclic transfer */ + channel_set_bit(dw, MASK.BLOCK, dwc->mask); + dwc_dostart(dwc, dwc->cdesc->desc[0]); + spin_unlock_irqrestore(&dwc->lock, flags); return 0; |