net: macb: Clear interrupt flags

A few interrupt flags were not cleared in the ISR, resulting in a sytem
trapped in the ISR in cases one of those interrupts occurred. Clear all
flags to avoid such situations.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb.c

@@ -951,6 +951,10 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id)
 		if (unlikely(status & (MACB_TX_ERR_FLAGS))) {
 			macb_writel(bp, IDR, MACB_TX_INT_FLAGS);
 			schedule_work(&bp->tx_error_task);
+
+			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
+				macb_writel(bp, ISR, MACB_TX_ERR_FLAGS);
+
 			break;
 		}
 
@@ -968,6 +972,9 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id)
 				bp->hw_stats.gem.rx_overruns++;
 			else
 				bp->hw_stats.macb.rx_overruns++;
+
+			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
+				macb_writel(bp, ISR, MACB_BIT(ISR_ROVR));
 		}
 
 		if (status & MACB_BIT(HRESP)) {
@@ -977,6 +984,9 @@ static irqreturn_t macb_interrupt(int irq, void *dev_id)
 			 * (work queue?)
 			 */
 			netdev_err(dev, "DMA bus error: HRESP not OK\n");
+
+			if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
+				macb_writel(bp, ISR, MACB_BIT(HRESP));
 		}
 
 		status = macb_readl(bp, ISR);