In the current implementation sf_pdma_tx_status() will never report about
descriptor error (it returns DMA_IN_PROGRESS even when currently processed
descriptor failed already).
In particular, this leads to polling until timeout in the dma_sync_wait()
from the dmaengine API.
* Make sf_pdma_tx_status() return DMA_ERROR for failed descriptors;
* Make sure that all accesses to the pdma channels state are protected by
spinlock from struct virt_dma_chan;
* Remove the code related with retries from struct sf_pdma_chan because it
is never used in the current driver implementation: chan->retries stays
0 during the whole lifetime.
Signed-off-by: Nikita Proshkin <n.proshkin@xxxxxxxxx>
---
drivers/dma/sf-pdma/sf-pdma.c | 95 ++++++++++-------------------------
drivers/dma/sf-pdma/sf-pdma.h | 3 --
2 files changed, 26 insertions(+), 72 deletions(-)
diff --git a/drivers/dma/sf-pdma/sf-pdma.c b/drivers/dma/sf-pdma/sf-pdma.c
index 428473611115..55b7c57eeec9 100644
--- a/drivers/dma/sf-pdma/sf-pdma.c
+++ b/drivers/dma/sf-pdma/sf-pdma.c
@@ -153,44 +153,6 @@ static void sf_pdma_free_chan_resources(struct dma_chan *dchan)
vchan_dma_desc_free_list(&chan->vchan, &head);
}
-static size_t sf_pdma_desc_residue(struct sf_pdma_chan *chan,
- dma_cookie_t cookie)
-{
- struct virt_dma_desc *vd = NULL;
- struct pdma_regs *regs = &chan->regs;
- unsigned long flags;
- u64 residue = 0;
- struct sf_pdma_desc *desc;
- struct dma_async_tx_descriptor *tx = NULL;
-
- spin_lock_irqsave(&chan->vchan.lock, flags);
-
- list_for_each_entry(vd, &chan->vchan.desc_submitted, node)
- if (vd->tx.cookie == cookie)
- tx = &vd->tx;
-
- if (!tx)
- goto out;
-
- if (cookie == tx->chan->completed_cookie)
- goto out;
-
- if (cookie == tx->cookie) {
- residue = readq(regs->residue);
- } else {
- vd = vchan_find_desc(&chan->vchan, cookie);
- if (!vd)
- goto out;
-
- desc = to_sf_pdma_desc(vd);
- residue = desc->xfer_size;
- }
-
-out:
- spin_unlock_irqrestore(&chan->vchan.lock, flags);
- return residue;
-}
-
static enum dma_status
sf_pdma_tx_status(struct dma_chan *dchan,
dma_cookie_t cookie,
@@ -198,12 +160,27 @@ sf_pdma_tx_status(struct dma_chan *dchan,
{
struct sf_pdma_chan *chan = to_sf_pdma_chan(dchan);
enum dma_status status;
+ unsigned long flags;
+ struct virt_dma_desc *desc;
status = dma_cookie_status(dchan, cookie, txstate);
- if (txstate && status != DMA_ERROR)
- dma_set_residue(txstate, sf_pdma_desc_residue(chan, cookie));
+ if (status == DMA_COMPLETE) {
+ dma_set_residue(txstate, 0);
+ return status;
+ }
+
+ spin_lock_irqsave(&chan->vchan.lock, flags);
+
+ desc = vchan_find_desc(&chan->vchan, cookie);
+ if (chan->desc && cookie == chan->desc->async_tx->cookie) {
+ dma_set_residue(txstate, readq(chan->regs.residue));
+ status = chan->status;
+ } else if (desc) {
+ dma_set_residue(txstate, to_sf_pdma_desc(desc)->xfer_size);
+ }
+ spin_unlock_irqrestore(&chan->vchan.lock, flags);
return status;
}
@@ -217,7 +194,6 @@ static int sf_pdma_terminate_all(struct dma_chan *dchan)
sf_pdma_disable_request(chan);
kfree(chan->desc);
chan->desc = NULL;
- chan->xfer_err = false;
vchan_get_all_descriptors(&chan->vchan, &head);
spin_unlock_irqrestore(&chan->vchan.lock, flags);
vchan_dma_desc_free_list(&chan->vchan, &head);
@@ -278,7 +254,7 @@ static void sf_pdma_issue_pending(struct dma_chan *dchan)
spin_lock_irqsave(&chan->vchan.lock, flags);
- if (!chan->desc && vchan_issue_pending(&chan->vchan)) {
+ if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
/* vchan_issue_pending has made a check that desc in not NULL */
chan->desc = sf_pdma_get_first_pending_desc(chan);
sf_pdma_xfer_desc(chan);
@@ -300,15 +276,9 @@ static void sf_pdma_donebh_tasklet(struct tasklet_struct *t)
struct sf_pdma_chan *chan = from_tasklet(chan, t, done_tasklet);
unsigned long flags;
- spin_lock_irqsave(&chan->lock, flags);
- if (chan->xfer_err) {
- chan->retries = MAX_RETRY;
- chan->status = DMA_COMPLETE;
- chan->xfer_err = false;
- }
- spin_unlock_irqrestore(&chan->lock, flags);
-
spin_lock_irqsave(&chan->vchan.lock, flags);
+ chan->status = DMA_COMPLETE;
+
list_del(&chan->desc->vdesc.node);
vchan_cookie_complete(&chan->desc->vdesc);
@@ -322,23 +292,12 @@ static void sf_pdma_donebh_tasklet(struct tasklet_struct *t)
static void sf_pdma_errbh_tasklet(struct tasklet_struct *t)
{
struct sf_pdma_chan *chan = from_tasklet(chan, t, err_tasklet);
- struct sf_pdma_desc *desc = chan->desc;
unsigned long flags;
- spin_lock_irqsave(&chan->lock, flags);
- if (chan->retries <= 0) {
- /* fail to recover */
- spin_unlock_irqrestore(&chan->lock, flags);
- dmaengine_desc_get_callback_invoke(desc->async_tx, NULL);
- } else {
- /* retry */
- chan->retries--;
- chan->xfer_err = true;
- chan->status = DMA_ERROR;
-
- sf_pdma_enable_request(chan);
- spin_unlock_irqrestore(&chan->lock, flags);
- }
+ spin_lock_irqsave(&chan->vchan.lock, flags);
+ dmaengine_desc_get_callback_invoke(chan->desc->async_tx, NULL);
+ chan->status = DMA_ERROR;
+ spin_unlock_irqrestore(&chan->vchan.lock, flags);
}
static irqreturn_t sf_pdma_done_isr(int irq, void *dev_id)
@@ -374,9 +333,9 @@ static irqreturn_t sf_pdma_err_isr(int irq, void *dev_id)
struct sf_pdma_chan *chan = dev_id;
struct pdma_regs *regs = &chan->regs;
- spin_lock(&chan->lock);
+ spin_lock(&chan->vchan.lock);
writel((readl(regs->ctrl)) & ~PDMA_ERR_STATUS_MASK, regs->ctrl);
- spin_unlock(&chan->lock);
+ spin_unlock(&chan->vchan.lock);
tasklet_schedule(&chan->err_tasklet);
@@ -480,8 +439,6 @@ static void sf_pdma_setup_chans(struct sf_pdma *pdma)
chan->pdma = pdma;
chan->pm_state = RUNNING;
chan->slave_id = i;
- chan->xfer_err = false;
- spin_lock_init(&chan->lock);
chan->vchan.desc_free = sf_pdma_free_desc;
vchan_init(&chan->vchan, &pdma->dma_dev);
diff --git a/drivers/dma/sf-pdma/sf-pdma.h b/drivers/dma/sf-pdma/sf-pdma.h
index 215e07183d7e..ea1a062adc18 100644
--- a/drivers/dma/sf-pdma/sf-pdma.h
+++ b/drivers/dma/sf-pdma/sf-pdma.h
@@ -102,11 +102,8 @@ struct sf_pdma_chan {
struct tasklet_struct done_tasklet;
struct tasklet_struct err_tasklet;
struct pdma_regs regs;
- spinlock_t lock; /* protect chan data */
- bool xfer_err;
int txirq;
int errirq;
- int retries;
};
struct sf_pdma {
--
2.34.1
