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Merge branch 'fix/brcm' into fixes

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This commit is contained in:
Vinod Koul
2019-02-04 12:57:56 +05:30
parent 341198eda7 9e528c799d
commit 6d66c8d1a0
1 changed files with 25 additions and 45 deletions
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70
drivers/dma/bcm2835-dma.c
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@@ -406,38 +406,32 @@ 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; long int timeout = 10000;
cs = readl(chan_base + BCM2835_DMA_CS); /*
if (!(cs & BCM2835_DMA_ACTIVE)) * A zero control block address means the channel is idle.
* (The ACTIVE flag in the CS register is not a reliable indicator.)
*/
if (!readl(chan_base + BCM2835_DMA_ADDR))
return 0; return 0;
/* Write 0 to the active bit - Pause the DMA */ /* Write 0 to the active bit - Pause the DMA */
writel(0, chan_base + BCM2835_DMA_CS); writel(0, chan_base + BCM2835_DMA_CS);
/* Wait for any current AXI transfer to complete */ /* 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(); 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) if (!timeout)
return -ETIMEDOUT; dev_err(c->vc.chan.device->dev,
"failed to complete outstanding writes\n");
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);
writel(BCM2835_DMA_RESET, chan_base + BCM2835_DMA_CS);
return 0; return 0;
} }
@@ -476,8 +470,15 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data)
spin_lock_irqsave(&c->vc.lock, flags); spin_lock_irqsave(&c->vc.lock, flags);
/* Acknowledge interrupt */ /*
writel(BCM2835_DMA_INT, c->chan_base + BCM2835_DMA_CS); * Clear the INT flag to receive further interrupts. Keep the channel
* active in case the descriptor is cyclic or in case the client has
* already terminated the descriptor and issued a new one. (May happen
* if this IRQ handler is threaded.) If the channel is finished, it
* will remain idle despite the ACTIVE flag being set.
*/
writel(BCM2835_DMA_INT | BCM2835_DMA_ACTIVE,
c->chan_base + BCM2835_DMA_CS);
d = c->desc; d = c->desc;
@@ -485,11 +486,7 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data)
if (d->cyclic) { if (d->cyclic) {
/* call the cyclic callback */ /* call the cyclic callback */
vchan_cyclic_callback(&d->vd); vchan_cyclic_callback(&d->vd);
} else if (!readl(c->chan_base + BCM2835_DMA_ADDR)) {
/* Keep the DMA engine running */
writel(BCM2835_DMA_ACTIVE,
c->chan_base + BCM2835_DMA_CS);
} else {
vchan_cookie_complete(&c->desc->vd); vchan_cookie_complete(&c->desc->vd);
bcm2835_dma_start_desc(c); bcm2835_dma_start_desc(c);
} }
@@ -779,7 +776,6 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); struct bcm2835_chan *c = to_bcm2835_dma_chan(chan);
struct bcm2835_dmadev *d = to_bcm2835_dma_dev(c->vc.chan.device); struct bcm2835_dmadev *d = to_bcm2835_dma_dev(c->vc.chan.device);
unsigned long flags; unsigned long flags;
int timeout = 10000;
LIST_HEAD(head); LIST_HEAD(head);
spin_lock_irqsave(&c->vc.lock, flags); spin_lock_irqsave(&c->vc.lock, flags);
@@ -789,27 +785,11 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
list_del_init(&c->node); list_del_init(&c->node);
spin_unlock(&d->lock); spin_unlock(&d->lock);
/* /* stop DMA activity */
* Stop DMA activity: we assume the callback will not be called
* after bcm_dma_abort() returns (even if it does, it will see
* c->desc is NULL and exit.)
*/
if (c->desc) { if (c->desc) {
vchan_terminate_vdesc(&c->desc->vd); vchan_terminate_vdesc(&c->desc->vd);
c->desc = NULL; c->desc = NULL;
bcm2835_dma_abort(c->chan_base); bcm2835_dma_abort(c);
/* Wait for stopping */
while (--timeout) {
if (!(readl(c->chan_base + BCM2835_DMA_CS) &
BCM2835_DMA_ACTIVE))
break;
cpu_relax();
}
if (!timeout)
dev_err(d->ddev.dev, "DMA transfer could not be terminated\n");
} }
vchan_get_all_descriptors(&c->vc, &head); vchan_get_all_descriptors(&c->vc, &head);