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authorSinan Kaya <okaya@codeaurora.org>2016-10-21 12:37:58 -0400
committerVinod Koul <vinod.koul@intel.com>2016-11-03 18:55:45 +0530
commit0e858f8d6f66df25545861759e174023bd7d5c1f (patch)
tree7453e94e6d9807cf2c4866c1b18328facd65bc37 /drivers/dma/qcom
parent9483d9ae09452ad4cdf7f0bb0c0fae2775278c85 (diff)
downloadlinux-0e858f8d6f66df25545861759e174023bd7d5c1f.tar.bz2
dmaengine: qcom_hidma: protect common data structures
When MSI interrupts are supported, error and the transfer interrupt can come from multiple processor contexts. Each error interrupt is an MSI interrupt. If the channel is disabled by the first error interrupt, the remaining error interrupts will gracefully return in the interrupt handler. If an error is observed while servicing the completions in success case, the posting of the completions will be aborted as soon as channel disabled state is observed. The error interrupt handler will take it from there and finish the remaining completions. We don't want to create multiple success and error messages to be delivered to the client in mixed order. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/qcom')
-rw-r--r--drivers/dma/qcom/hidma_ll.c44
1 files changed, 11 insertions, 33 deletions
diff --git a/drivers/dma/qcom/hidma_ll.c b/drivers/dma/qcom/hidma_ll.c
index 9193f466c9e7..7fe43afcbe32 100644
--- a/drivers/dma/qcom/hidma_ll.c
+++ b/drivers/dma/qcom/hidma_ll.c
@@ -198,13 +198,16 @@ static void hidma_ll_tre_complete(unsigned long arg)
}
}
-static int hidma_post_completed(struct hidma_lldev *lldev, int tre_iterator,
- u8 err_info, u8 err_code)
+static int hidma_post_completed(struct hidma_lldev *lldev, u8 err_info,
+ u8 err_code)
{
struct hidma_tre *tre;
unsigned long flags;
+ u32 tre_iterator;
spin_lock_irqsave(&lldev->lock, flags);
+
+ tre_iterator = lldev->tre_processed_off;
tre = lldev->pending_tre_list[tre_iterator / HIDMA_TRE_SIZE];
if (!tre) {
spin_unlock_irqrestore(&lldev->lock, flags);
@@ -223,6 +226,9 @@ static int hidma_post_completed(struct hidma_lldev *lldev, int tre_iterator,
atomic_set(&lldev->pending_tre_count, 0);
}
+ HIDMA_INCREMENT_ITERATOR(tre_iterator, HIDMA_TRE_SIZE,
+ lldev->tre_ring_size);
+ lldev->tre_processed_off = tre_iterator;
spin_unlock_irqrestore(&lldev->lock, flags);
tre->err_info = err_info;
@@ -244,13 +250,11 @@ static int hidma_post_completed(struct hidma_lldev *lldev, int tre_iterator,
static int hidma_handle_tre_completion(struct hidma_lldev *lldev)
{
u32 evre_ring_size = lldev->evre_ring_size;
- u32 tre_ring_size = lldev->tre_ring_size;
u32 err_info, err_code, evre_write_off;
- u32 tre_iterator, evre_iterator;
+ u32 evre_iterator;
u32 num_completed = 0;
evre_write_off = readl_relaxed(lldev->evca + HIDMA_EVCA_WRITE_PTR_REG);
- tre_iterator = lldev->tre_processed_off;
evre_iterator = lldev->evre_processed_off;
if ((evre_write_off > evre_ring_size) ||
@@ -273,12 +277,9 @@ static int hidma_handle_tre_completion(struct hidma_lldev *lldev)
err_code =
(cfg >> HIDMA_EVRE_CODE_BIT_POS) & HIDMA_EVRE_CODE_MASK;
- if (hidma_post_completed(lldev, tre_iterator, err_info,
- err_code))
+ if (hidma_post_completed(lldev, err_info, err_code))
break;
- HIDMA_INCREMENT_ITERATOR(tre_iterator, HIDMA_TRE_SIZE,
- tre_ring_size);
HIDMA_INCREMENT_ITERATOR(evre_iterator, HIDMA_EVRE_SIZE,
evre_ring_size);
@@ -302,16 +303,10 @@ static int hidma_handle_tre_completion(struct hidma_lldev *lldev)
if (num_completed) {
u32 evre_read_off = (lldev->evre_processed_off +
HIDMA_EVRE_SIZE * num_completed);
- u32 tre_read_off = (lldev->tre_processed_off +
- HIDMA_TRE_SIZE * num_completed);
-
evre_read_off = evre_read_off % evre_ring_size;
- tre_read_off = tre_read_off % tre_ring_size;
-
writel(evre_read_off, lldev->evca + HIDMA_EVCA_DOORBELL_REG);
/* record the last processed tre offset */
- lldev->tre_processed_off = tre_read_off;
lldev->evre_processed_off = evre_read_off;
}
@@ -321,27 +316,10 @@ static int hidma_handle_tre_completion(struct hidma_lldev *lldev)
void hidma_cleanup_pending_tre(struct hidma_lldev *lldev, u8 err_info,
u8 err_code)
{
- u32 tre_iterator;
- u32 tre_ring_size = lldev->tre_ring_size;
- int num_completed = 0;
- u32 tre_read_off;
-
- tre_iterator = lldev->tre_processed_off;
while (atomic_read(&lldev->pending_tre_count)) {
- if (hidma_post_completed(lldev, tre_iterator, err_info,
- err_code))
+ if (hidma_post_completed(lldev, err_info, err_code))
break;
- HIDMA_INCREMENT_ITERATOR(tre_iterator, HIDMA_TRE_SIZE,
- tre_ring_size);
- num_completed++;
}
- tre_read_off = (lldev->tre_processed_off +
- HIDMA_TRE_SIZE * num_completed);
-
- tre_read_off = tre_read_off % tre_ring_size;
-
- /* record the last processed tre offset */
- lldev->tre_processed_off = tre_read_off;
}
static int hidma_ll_reset(struct hidma_lldev *lldev)