Merge branch 'sh_eth'

Ben Hutchings says:

====================
Fixes for sh_eth #3

I'm continuing review and testing of Ethernet support on the R-Car H2
chip.  This series fixes the last of the more serious issues I've found.

These are not tested on any of the other supported chips.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/sh_eth.c

@@ -396,6 +396,9 @@ static const u16 sh_eth_offset_fast_sh3_sh2[SH_ETH_MAX_REGISTER_OFFSET] = {
 	[TSU_ADRL31]	= 0x01fc,
 };
 
+static void sh_eth_rcv_snd_disable(struct net_device *ndev);
+static struct net_device_stats *sh_eth_get_stats(struct net_device *ndev);
+
 static bool sh_eth_is_gether(struct sh_eth_private *mdp)
 {
 	return mdp->reg_offset == sh_eth_offset_gigabit;
@@ -1120,6 +1123,7 @@ static void sh_eth_ring_format(struct net_device *ndev)
 	int rx_ringsize = sizeof(*rxdesc) * mdp->num_rx_ring;
 	int tx_ringsize = sizeof(*txdesc) * mdp->num_tx_ring;
 	int skbuff_size = mdp->rx_buf_sz + SH_ETH_RX_ALIGN - 1;
+	dma_addr_t dma_addr;
 
 	mdp->cur_rx = 0;
 	mdp->cur_tx = 0;
@@ -1133,7 +1137,6 @@ static void sh_eth_ring_format(struct net_device *ndev)
 		/* skb */
 		mdp->rx_skbuff[i] = NULL;
 		skb = netdev_alloc_skb(ndev, skbuff_size);
-		mdp->rx_skbuff[i] = skb;
 		if (skb == NULL)
 			break;
 		sh_eth_set_receive_align(skb);
@@ -1142,9 +1145,15 @@ static void sh_eth_ring_format(struct net_device *ndev)
 		rxdesc = &mdp->rx_ring[i];
 		/* The size of the buffer is a multiple of 16 bytes. */
 		rxdesc->buffer_length = ALIGN(mdp->rx_buf_sz, 16);
-		dma_map_single(&ndev->dev, skb->data, rxdesc->buffer_length,
-			       DMA_FROM_DEVICE);
-		rxdesc->addr = virt_to_phys(skb->data);
+		dma_addr = dma_map_single(&ndev->dev, skb->data,
+					  rxdesc->buffer_length,
+					  DMA_FROM_DEVICE);
+		if (dma_mapping_error(&ndev->dev, dma_addr)) {
+			kfree_skb(skb);
+			break;
+		}
+		mdp->rx_skbuff[i] = skb;
+		rxdesc->addr = dma_addr;
 		rxdesc->status = cpu_to_edmac(mdp, RD_RACT | RD_RFP);
 
 		/* Rx descriptor address set */
@@ -1358,6 +1367,33 @@ static int sh_eth_dev_init(struct net_device *ndev, bool start)
 	return ret;
 }
 
+static void sh_eth_dev_exit(struct net_device *ndev)
+{
+	struct sh_eth_private *mdp = netdev_priv(ndev);
+	int i;
+
+	/* Deactivate all TX descriptors, so DMA should stop at next
+	 * packet boundary if it's currently running
+	 */
+	for (i = 0; i < mdp->num_tx_ring; i++)
+		mdp->tx_ring[i].status &= ~cpu_to_edmac(mdp, TD_TACT);
+
+	/* Disable TX FIFO egress to MAC */
+	sh_eth_rcv_snd_disable(ndev);
+
+	/* Stop RX DMA at next packet boundary */
+	sh_eth_write(ndev, 0, EDRRR);
+
+	/* Aside from TX DMA, we can't tell when the hardware is
+	 * really stopped, so we need to reset to make sure.
+	 * Before doing that, wait for long enough to *probably*
+	 * finish transmitting the last packet and poll stats.
+	 */
+	msleep(2); /* max frame time at 10 Mbps < 1250 us */
+	sh_eth_get_stats(ndev);
+	sh_eth_reset(ndev);
+}
+
 /* free Tx skb function */
 static int sh_eth_txfree(struct net_device *ndev)
 {
@@ -1402,6 +1438,7 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota)
 	u16 pkt_len = 0;
 	u32 desc_status;
 	int skbuff_size = mdp->rx_buf_sz + SH_ETH_RX_ALIGN - 1;
+	dma_addr_t dma_addr;
 
 	boguscnt = min(boguscnt, *quota);
 	limit = boguscnt;
@@ -1449,9 +1486,9 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota)
 			mdp->rx_skbuff[entry] = NULL;
 			if (mdp->cd->rpadir)
 				skb_reserve(skb, NET_IP_ALIGN);
-			dma_sync_single_for_cpu(&ndev->dev, rxdesc->addr,
-						ALIGN(mdp->rx_buf_sz, 16),
-						DMA_FROM_DEVICE);
+			dma_unmap_single(&ndev->dev, rxdesc->addr,
+					 ALIGN(mdp->rx_buf_sz, 16),
+					 DMA_FROM_DEVICE);
 			skb_put(skb, pkt_len);
 			skb->protocol = eth_type_trans(skb, ndev);
 			netif_receive_skb(skb);
@@ -1471,15 +1508,20 @@ static int sh_eth_rx(struct net_device *ndev, u32 intr_status, int *quota)
 
 		if (mdp->rx_skbuff[entry] == NULL) {
 			skb = netdev_alloc_skb(ndev, skbuff_size);
-			mdp->rx_skbuff[entry] = skb;
 			if (skb == NULL)
 				break;	/* Better luck next round. */
 			sh_eth_set_receive_align(skb);
-			dma_map_single(&ndev->dev, skb->data,
-				       rxdesc->buffer_length, DMA_FROM_DEVICE);
+			dma_addr = dma_map_single(&ndev->dev, skb->data,
+						  rxdesc->buffer_length,
+						  DMA_FROM_DEVICE);
+			if (dma_mapping_error(&ndev->dev, dma_addr)) {
+				kfree_skb(skb);
+				break;
+			}
+			mdp->rx_skbuff[entry] = skb;
 
 			skb_checksum_none_assert(skb);
-			rxdesc->addr = virt_to_phys(skb->data);
+			rxdesc->addr = dma_addr;
 		}
 		if (entry >= mdp->num_rx_ring - 1)
 			rxdesc->status |=
@@ -1575,7 +1617,6 @@ static void sh_eth_error(struct net_device *ndev, int intr_status)
 		if (intr_status & EESR_RFRMER) {
 			/* Receive Frame Overflow int */
 			ndev->stats.rx_frame_errors++;
-			netif_err(mdp, rx_err, ndev, "Receive Abort\n");
 		}
 	}
 
@@ -1594,13 +1635,11 @@ static void sh_eth_error(struct net_device *ndev, int intr_status)
 	if (intr_status & EESR_RDE) {
 		/* Receive Descriptor Empty int */
 		ndev->stats.rx_over_errors++;
-		netif_err(mdp, rx_err, ndev, "Receive Descriptor Empty\n");
 	}
 
 	if (intr_status & EESR_RFE) {
 		/* Receive FIFO Overflow int */
 		ndev->stats.rx_fifo_errors++;
-		netif_err(mdp, rx_err, ndev, "Receive FIFO Overflow\n");
 	}
 
 	if (!mdp->cd->no_ade && (intr_status & EESR_ADE)) {
@@ -1989,9 +2028,7 @@ static int sh_eth_set_ringparam(struct net_device *ndev,
 		napi_synchronize(&mdp->napi);
 		sh_eth_write(ndev, 0x0000, EESIPR);
 
-		/* Stop the chip's Tx and Rx processes. */
-		sh_eth_write(ndev, 0, EDTRR);
-		sh_eth_write(ndev, 0, EDRRR);
+		sh_eth_dev_exit(ndev);
 
 		/* Free all the skbuffs in the Rx queue. */
 		sh_eth_ring_free(ndev);
@@ -2149,6 +2186,10 @@ static int sh_eth_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 				 skb->len + 2);
 	txdesc->addr = dma_map_single(&ndev->dev, skb->data, skb->len,
 				      DMA_TO_DEVICE);
+	if (dma_mapping_error(&ndev->dev, txdesc->addr)) {
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
 	txdesc->buffer_length = skb->len;
 
 	if (entry >= mdp->num_tx_ring - 1)
@@ -2210,11 +2251,8 @@ static int sh_eth_close(struct net_device *ndev)
 	napi_disable(&mdp->napi);
 	sh_eth_write(ndev, 0x0000, EESIPR);
 
-	/* Stop the chip's Tx and Rx processes. */
-	sh_eth_write(ndev, 0, EDTRR);
-	sh_eth_write(ndev, 0, EDRRR);
+	sh_eth_dev_exit(ndev);
 
-	sh_eth_get_stats(ndev);
 	/* PHY Disconnect */
 	if (mdp->phydev) {
 		phy_stop(mdp->phydev);