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-rw-r--r--drivers/dma/bcm2835-dma.c41
1 files changed, 9 insertions, 32 deletions
diff --git a/drivers/dma/bcm2835-dma.c b/drivers/dma/bcm2835-dma.c
index 0c3f5c71bb48..ae10f5614f95 100644
--- a/drivers/dma/bcm2835-dma.c
+++ b/drivers/dma/bcm2835-dma.c
@@ -406,13 +406,11 @@ static void bcm2835_dma_fill_cb_chain_with_sg(
}
}
-static int bcm2835_dma_abort(void __iomem *chan_base)
+static int bcm2835_dma_abort(struct bcm2835_chan *c)
{
- unsigned long cs;
+ void __iomem *chan_base = c->chan_base;
long int timeout = 10000;
- cs = readl(chan_base + BCM2835_DMA_CS);
-
/*
* A zero control block address means the channel is idle.
* (The ACTIVE flag in the CS register is not a reliable indicator.)
@@ -424,25 +422,16 @@ static int bcm2835_dma_abort(void __iomem *chan_base)
writel(0, chan_base + BCM2835_DMA_CS);
/* Wait for any current AXI transfer to complete */
- while ((cs & BCM2835_DMA_ISPAUSED) && --timeout) {
+ while ((readl(chan_base + BCM2835_DMA_CS) &
+ BCM2835_DMA_WAITING_FOR_WRITES) && --timeout)
cpu_relax();
- cs = readl(chan_base + BCM2835_DMA_CS);
- }
- /* We'll un-pause when we set of our next DMA */
+ /* Peripheral might be stuck and fail to signal AXI write responses */
if (!timeout)
- return -ETIMEDOUT;
-
- if (!(cs & BCM2835_DMA_ACTIVE))
- return 0;
-
- /* Terminate the control block chain */
- writel(0, chan_base + BCM2835_DMA_NEXTCB);
-
- /* Abort the whole DMA */
- writel(BCM2835_DMA_ABORT | BCM2835_DMA_ACTIVE,
- chan_base + BCM2835_DMA_CS);
+ dev_err(c->vc.chan.device->dev,
+ "failed to complete outstanding writes\n");
+ writel(BCM2835_DMA_RESET, chan_base + BCM2835_DMA_CS);
return 0;
}
@@ -787,7 +776,6 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
struct bcm2835_dmadev *d = to_bcm2835_dma_dev(c->vc.chan.device);
unsigned long flags;
- int timeout = 10000;
LIST_HEAD(head);
spin_lock_irqsave(&c->vc.lock, flags);
@@ -801,18 +789,7 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
if (c->desc) {
vchan_terminate_vdesc(&c->desc->vd);
c->desc = NULL;
- bcm2835_dma_abort(c->chan_base);
-
- /* Wait for stopping */
- while (--timeout) {
- if (!readl(c->chan_base + BCM2835_DMA_ADDR))
- break;
-
- cpu_relax();
- }
-
- if (!timeout)
- dev_err(d->ddev.dev, "DMA transfer could not be terminated\n");
+ bcm2835_dma_abort(c);
}
vchan_get_all_descriptors(&c->vc, &head);