diff options
| author | Krzysztof Kozlowski <k.kozlowski@samsung.com> | 2015-05-21 09:34:09 +0900 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2015-05-22 18:01:03 +0530 |
| commit | 81cc6edc08705ac0146fe6ac14a0982a31ce6f3d (patch) | |
| tree | a2f9eba6363f198527f5553aef5ed72a005c10fc /drivers/dma/pl330.c | |
| parent | 5ebe6afaf0057ac3eaeb98defd5456894b446d22 (diff) | |
| download | talos-op-linux-81cc6edc08705ac0146fe6ac14a0982a31ce6f3d.tar.gz talos-op-linux-81cc6edc08705ac0146fe6ac14a0982a31ce6f3d.zip | |
dmaengine: pl330: Fix hang on dmaengine_terminate_all on certain boards
The pl330 device could hang infinitely on certain boards when DMA
channels are terminated.
It was caused by lack of runtime resume when executing
pl330_terminate_all() which calls the _stop() function. _stop() accesses
device register and can loop infinitely while checking for device state.
The hang was confirmed by Dinh Nguyen on Altera SOCFPGA Cyclone V
board during boot. It can be also triggered with:
$ echo 1 > /sys/module/dmatest/parameters/iterations
$ echo dma1chan0 > /sys/module/dmatest/parameters/channel
$ echo 1 > /sys/module/dmatest/parameters/run
$ sleep 1
$ cat /sys/module/dmatest/parameters/run
Reported-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12")
Cc: <stable@vger.kernel.org>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/pl330.c')
| -rw-r--r-- | drivers/dma/pl330.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index a7d9d3029b14..340f9e607cd8 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2127,6 +2127,7 @@ static int pl330_terminate_all(struct dma_chan *chan) struct pl330_dmac *pl330 = pch->dmac; LIST_HEAD(list); + pm_runtime_get_sync(pl330->ddma.dev); spin_lock_irqsave(&pch->lock, flags); spin_lock(&pl330->lock); _stop(pch->thread); @@ -2151,6 +2152,8 @@ static int pl330_terminate_all(struct dma_chan *chan) list_splice_tail_init(&pch->work_list, &pl330->desc_pool); list_splice_tail_init(&pch->completed_list, &pl330->desc_pool); spin_unlock_irqrestore(&pch->lock, flags); + pm_runtime_mark_last_busy(pl330->ddma.dev); + pm_runtime_put_autosuspend(pl330->ddma.dev); return 0; } |
