Merge branch 'at91-4.14-trunk/dma' into linux-4.14-at91

drivers/dma/at_xdmac.c

@@ -203,6 +203,7 @@ struct at_xdmac_chan {
  u32 save_cim;
  u32 save_cnda;
  u32 save_cndc;
+ u32 irq_status;
  unsigned long status;
  struct tasklet_struct tasklet;
  struct dma_slave_config sconfig;
@@ -307,6 +308,11 @@ static inline int at_xdmac_csize(u32 maxburst)
  return csize;
 };
 
+static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
+{
+ return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
+}
+
 static inline u8 at_xdmac_get_dwidth(u32 cfg)
 {
  return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
@@ -388,7 +394,13 @@ static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
  at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 
  at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
- reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE | AT_XDMAC_CIE_ROIE;
+ reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
+ /*
+ * Request Overflow Error is only for peripheral synchronized transfers
+ */
+ if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
+ reg |= AT_XDMAC_CIE_ROIE;
+
  /*
  * There is no end of list when doing cyclic dma, we need to get
  * an interrupt after each periods.
@@ -1574,38 +1586,73 @@ static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
  dmaengine_desc_get_callback_invoke(txd, NULL);
 }
 
+static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
+{
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ struct at_xdmac_desc *bad_desc;
+
+ /*
+ * The descriptor currently at the head of the active list is
+ * broked. Since we don't have any way to report errors, we'll
+ * just have to scream loudly and try to carry on.
+ */
+ if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
+ dev_err(chan2dev(&atchan->chan), "read bus error!!!");
+ if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
+ dev_err(chan2dev(&atchan->chan), "write bus error!!!");
+ if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
+ dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
+
+ spin_lock_bh(&atchan->lock);
+ /* Channel must be disabled first as it's not done automatically */
+ at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
+ while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
+ cpu_relax();
+ bad_desc = list_first_entry(&atchan->xfers_list,
+ struct at_xdmac_desc,
+ xfer_node);
+ spin_unlock_bh(&atchan->lock);
+ /* Print bad descriptor's details if needed */
+ dev_dbg(chan2dev(&atchan->chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
+ __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
+ bad_desc->lld.mbr_ubc);
+
+ /* Then continue with usual descriptor management */
+}
+
 static void at_xdmac_tasklet(unsigned long data)
 {
  struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data;
  struct at_xdmac_desc *desc;
  u32 error_mask;
 
- dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08lx\n",
-  __func__, atchan->status);
+ dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
+ __func__, atchan->irq_status);
 
  error_mask = AT_XDMAC_CIS_RBEIS
  | AT_XDMAC_CIS_WBEIS
  | AT_XDMAC_CIS_ROIS;
 
  if (at_xdmac_chan_is_cyclic(atchan)) {
  at_xdmac_handle_cyclic(atchan);
- } else if ((atchan->status & AT_XDMAC_CIS_LIS)
- || (atchan->status & error_mask)) {
+ } else if ((atchan->irq_status & AT_XDMAC_CIS_LIS)
+ || (atchan->irq_status & error_mask)) {
  struct dma_async_tx_descriptor *txd;
 
- if (atchan->status & AT_XDMAC_CIS_RBEIS)
- dev_err(chan2dev(&atchan->chan), "read bus error!!!");
- if (atchan->status & AT_XDMAC_CIS_WBEIS)
- dev_err(chan2dev(&atchan->chan), "write bus error!!!");
- if (atchan->status & AT_XDMAC_CIS_ROIS)
- dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
+ if (atchan->irq_status & error_mask)
+ at_xdmac_handle_error(atchan);
 
  spin_lock_bh(&atchan->lock);
  desc = list_first_entry(&atchan->xfers_list,
  struct at_xdmac_desc,
  xfer_node);
  dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
- BUG_ON(!desc->active_xfer);
+ if (!desc->active_xfer) {
+ dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
+ spin_unlock_bh(&atchan->lock);
+ return;
+ }
 
  txd = &desc->tx_dma_desc;
 
@@ -1652,7 +1699,7 @@ static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
  atchan = &atxdmac->chan[i];
  chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
  chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
- atchan->status = chan_status & chan_imr;
+ atchan->irq_status = chan_status & chan_imr;
  dev_vdbg(atxdmac->dma.dev,
  "%s: chan%d: imr=0x%x, status=0x%x\n",
  __func__, i, chan_imr, chan_status);
@@ -1666,7 +1713,7 @@ static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
  at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
  at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
 
- if (atchan->status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
+ if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
  at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
 
  tasklet_schedule(&atchan->tasklet);