openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Merge branch 'fix/brcm' into fixes

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
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
drivers/dma/bcm2835-dma.c
View File

@ -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;
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;
/* Write 0 to the active bit - Pause the DMA */
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;
}
@ -476,8 +470,15 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data)
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;
@ -485,11 +486,7 @@ static irqreturn_t bcm2835_dma_callback(int irq, void *data)
if (d->cyclic) {
/* call the cyclic callback */
vchan_cyclic_callback(&d->vd);
/* Keep the DMA engine running */
writel(BCM2835_DMA_ACTIVE,
c->chan_base + BCM2835_DMA_CS);
} else {
} else if (!readl(c->chan_base + BCM2835_DMA_ADDR)) {
vchan_cookie_complete(&c->desc->vd);
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_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);
@ -789,27 +785,11 @@ static int bcm2835_dma_terminate_all(struct dma_chan *chan)
list_del_init(&c->node);
spin_unlock(&d->lock);
/*
* 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.)
*/
/* stop DMA activity */
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_CS) &
BCM2835_DMA_ACTIVE))
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);