1 files changed, 130 insertions, 40 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
index f6014d330b2e..53f5f66ec2ee 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
@@ -1085,10 +1085,10 @@ static void xgbe_rx_desc_reset(struct xgbe_ring_data *rdata)
 	 *   Set buffer 2 (hi) address to buffer dma address (hi) and
 	 *     set control bits OWN and INTE
 	 */
-	rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->rx_hdr.dma));
-	rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->rx_hdr.dma));
-	rdesc->desc2 = cpu_to_le32(lower_32_bits(rdata->rx_buf.dma));
-	rdesc->desc3 = cpu_to_le32(upper_32_bits(rdata->rx_buf.dma));
+	rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->rx.hdr.dma));
+	rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->rx.hdr.dma));
+	rdesc->desc2 = cpu_to_le32(lower_32_bits(rdata->rx.buf.dma));
+	rdesc->desc3 = cpu_to_le32(upper_32_bits(rdata->rx.buf.dma));
 
 	XGMAC_SET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, INTE,
 			  rdata->interrupt ? 1 : 0);
@@ -1325,6 +1325,29 @@ static void xgbe_config_dcb_pfc(struct xgbe_prv_data *pdata)
 	xgbe_config_flow_control(pdata);
 }
 
+static void xgbe_tx_start_xmit(struct xgbe_channel *channel,
+			       struct xgbe_ring *ring)
+{
+	struct xgbe_prv_data *pdata = channel->pdata;
+	struct xgbe_ring_data *rdata;
+
+	/* Issue a poll command to Tx DMA by writing address
+	 * of next immediate free descriptor */
+	rdata = XGBE_GET_DESC_DATA(ring, ring->cur);
+	XGMAC_DMA_IOWRITE(channel, DMA_CH_TDTR_LO,
+			  lower_32_bits(rdata->rdesc_dma));
+
+	/* Start the Tx coalescing timer */
+	if (pdata->tx_usecs && !channel->tx_timer_active) {
+		channel->tx_timer_active = 1;
+		hrtimer_start(&channel->tx_timer,
+			      ktime_set(0, pdata->tx_usecs * NSEC_PER_USEC),
+			      HRTIMER_MODE_REL);
+	}
+
+	ring->tx.xmit_more = 0;
+}
+
 static void xgbe_dev_xmit(struct xgbe_channel *channel)
 {
 	struct xgbe_prv_data *pdata = channel->pdata;
@@ -1334,7 +1357,7 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 	struct xgbe_packet_data *packet = &ring->packet_data;
 	unsigned int csum, tso, vlan;
 	unsigned int tso_context, vlan_context;
-	unsigned int tx_coalesce, tx_frames;
+	unsigned int tx_set_ic;
 	int start_index = ring->cur;
 	int i;
 
@@ -1357,10 +1380,26 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 	else
 		vlan_context = 0;
 
-	tx_coalesce = (pdata->tx_usecs || pdata->tx_frames) ? 1 : 0;
-	tx_frames = pdata->tx_frames;
-	if (tx_coalesce && !channel->tx_timer_active)
-		ring->coalesce_count = 0;
+	/* Determine if an interrupt should be generated for this Tx:
+	 *   Interrupt:
+	 *     - Tx frame count exceeds the frame count setting
+	 *     - Addition of Tx frame count to the frame count since the
+	 *       last interrupt was set exceeds the frame count setting
+	 *   No interrupt:
+	 *     - No frame count setting specified (ethtool -C ethX tx-frames 0)
+	 *     - Addition of Tx frame count to the frame count since the
+	 *       last interrupt was set does not exceed the frame count setting
+	 */
+	ring->coalesce_count += packet->tx_packets;
+	if (!pdata->tx_frames)
+		tx_set_ic = 0;
+	else if (packet->tx_packets > pdata->tx_frames)
+		tx_set_ic = 1;
+	else if ((ring->coalesce_count % pdata->tx_frames) <
+		 packet->tx_packets)
+		tx_set_ic = 1;
+	else
+		tx_set_ic = 0;
 
 	rdata = XGBE_GET_DESC_DATA(ring, ring->cur);
 	rdesc = rdata->rdesc;
@@ -1427,13 +1466,6 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 	if (XGMAC_GET_BITS(packet->attributes, TX_PACKET_ATTRIBUTES, PTP))
 		XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, TTSE, 1);
 
-	/* Set IC bit based on Tx coalescing settings */
-	XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, IC, 1);
-	if (tx_coalesce && (!tx_frames ||
-			    (++ring->coalesce_count % tx_frames)))
-		/* Clear IC bit */
-		XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, IC, 0);
-
 	/* Mark it as First Descriptor */
 	XGMAC_SET_BITS_LE(rdesc->desc3, TX_NORMAL_DESC3, FD, 1);
 
@@ -1478,13 +1510,6 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 		XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, HL_B1L,
 				  rdata->skb_dma_len);
 
-		/* Set IC bit based on Tx coalescing settings */
-		XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, IC, 1);
-		if (tx_coalesce && (!tx_frames ||
-				    (++ring->coalesce_count % tx_frames)))
-			/* Clear IC bit */
-			XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, IC, 0);
-
 		/* Set OWN bit */
 		XGMAC_SET_BITS_LE(rdesc->desc3, TX_NORMAL_DESC3, OWN, 1);
 
@@ -1500,6 +1525,14 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 	/* Set LAST bit for the last descriptor */
 	XGMAC_SET_BITS_LE(rdesc->desc3, TX_NORMAL_DESC3, LD, 1);
 
+	/* Set IC bit based on Tx coalescing settings */
+	if (tx_set_ic)
+		XGMAC_SET_BITS_LE(rdesc->desc2, TX_NORMAL_DESC2, IC, 1);
+
+	/* Save the Tx info to report back during cleanup */
+	rdata->tx.packets = packet->tx_packets;
+	rdata->tx.bytes = packet->tx_bytes;
+
 	/* In case the Tx DMA engine is running, make sure everything
 	 * is written to the descriptor(s) before setting the OWN bit
 	 * for the first descriptor
@@ -1518,20 +1551,13 @@ static void xgbe_dev_xmit(struct xgbe_channel *channel)
 	/* Make sure ownership is written to the descriptor */
 	wmb();
 
-	/* Issue a poll command to Tx DMA by writing address
-	 * of next immediate free descriptor */
 	ring->cur++;
-	rdata = XGBE_GET_DESC_DATA(ring, ring->cur);
-	XGMAC_DMA_IOWRITE(channel, DMA_CH_TDTR_LO,
-			  lower_32_bits(rdata->rdesc_dma));
-
-	/* Start the Tx coalescing timer */
-	if (tx_coalesce && !channel->tx_timer_active) {
-		channel->tx_timer_active = 1;
-		hrtimer_start(&channel->tx_timer,
-			      ktime_set(0, pdata->tx_usecs * NSEC_PER_USEC),
-			      HRTIMER_MODE_REL);
-	}
+	if (!packet->skb->xmit_more ||
+	    netif_xmit_stopped(netdev_get_tx_queue(pdata->netdev,
+						   channel->queue_index)))
+		xgbe_tx_start_xmit(channel, ring);
+	else
+		ring->tx.xmit_more = 1;
 
 	DBGPR("  %s: descriptors %u to %u written\n",
 	      channel->name, start_index & (ring->rdesc_count - 1),
@@ -1558,6 +1584,9 @@ static int xgbe_dev_read(struct xgbe_channel *channel)
 	if (XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, OWN))
 		return 1;
 
+	/* Make sure descriptor fields are read after reading the OWN bit */
+	rmb();
+
 #ifdef XGMAC_ENABLE_RX_DESC_DUMP
 	xgbe_dump_rx_desc(ring, rdesc, ring->cur);
 #endif
@@ -1583,8 +1612,8 @@ static int xgbe_dev_read(struct xgbe_channel *channel)
 
 	/* Get the header length */
 	if (XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, FD))
-		rdata->hdr_len = XGMAC_GET_BITS_LE(rdesc->desc2,
-						   RX_NORMAL_DESC2, HL);
+		rdata->rx.hdr_len = XGMAC_GET_BITS_LE(rdesc->desc2,
+						      RX_NORMAL_DESC2, HL);
 
 	/* Get the RSS hash */
 	if (XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, RSV)) {
@@ -1607,7 +1636,7 @@ static int xgbe_dev_read(struct xgbe_channel *channel)
 	}
 
 	/* Get the packet length */
-	rdata->len = XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, PL);
+	rdata->rx.len = XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, PL);
 
 	if (!XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, LD)) {
 		/* Not all the data has been transferred for this packet */
@@ -1630,7 +1659,8 @@ static int xgbe_dev_read(struct xgbe_channel *channel)
 	etlt = XGMAC_GET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, ETLT);
 	DBGPR("  err=%u, etlt=%#x\n", err, etlt);
 
-	if (!err || (err && !etlt)) {
+	if (!err || !etlt) {
+		/* No error if err is 0 or etlt is 0 */
 		if ((etlt == 0x09) &&
 		    (netdev->features & NETIF_F_HW_VLAN_CTAG_RX)) {
 			XGMAC_SET_BITS(packet->attributes, RX_PACKET_ATTRIBUTES,
@@ -2450,6 +2480,47 @@ static void xgbe_config_mmc(struct xgbe_prv_data *pdata)
 	XGMAC_IOWRITE_BITS(pdata, MMC_CR, CR, 1);
 }
 
+static void xgbe_prepare_tx_stop(struct xgbe_prv_data *pdata,
+				 struct xgbe_channel *channel)
+{
+	unsigned int tx_dsr, tx_pos, tx_qidx;
+	unsigned int tx_status;
+	unsigned long tx_timeout;
+
+	/* Calculate the status register to read and the position within */
+	if (channel->queue_index < DMA_DSRX_FIRST_QUEUE) {
+		tx_dsr = DMA_DSR0;
+		tx_pos = (channel->queue_index * DMA_DSR_Q_WIDTH) +
+			 DMA_DSR0_TPS_START;
+	} else {
+		tx_qidx = channel->queue_index - DMA_DSRX_FIRST_QUEUE;
+
+		tx_dsr = DMA_DSR1 + ((tx_qidx / DMA_DSRX_QPR) * DMA_DSRX_INC);
+		tx_pos = ((tx_qidx % DMA_DSRX_QPR) * DMA_DSR_Q_WIDTH) +
+			 DMA_DSRX_TPS_START;
+	}
+
+	/* The Tx engine cannot be stopped if it is actively processing
+	 * descriptors. Wait for the Tx engine to enter the stopped or
+	 * suspended state.  Don't wait forever though...
+	 */
+	tx_timeout = jiffies + (XGBE_DMA_STOP_TIMEOUT * HZ);
+	while (time_before(jiffies, tx_timeout)) {
+		tx_status = XGMAC_IOREAD(pdata, tx_dsr);
+		tx_status = GET_BITS(tx_status, tx_pos, DMA_DSR_TPS_WIDTH);
+		if ((tx_status == DMA_TPS_STOPPED) ||
+		    (tx_status == DMA_TPS_SUSPENDED))
+			break;
+
+		usleep_range(500, 1000);
+	}
+
+	if (!time_before(jiffies, tx_timeout))
+		netdev_info(pdata->netdev,
+			    "timed out waiting for Tx DMA channel %u to stop\n",
+			    channel->queue_index);
+}
+
 static void xgbe_enable_tx(struct xgbe_prv_data *pdata)
 {
 	struct xgbe_channel *channel;
@@ -2478,6 +2549,15 @@ static void xgbe_disable_tx(struct xgbe_prv_data *pdata)
 	struct xgbe_channel *channel;
 	unsigned int i;
 
+	/* Prepare for Tx DMA channel stop */
+	channel = pdata->channel;
+	for (i = 0; i < pdata->channel_count; i++, channel++) {
+		if (!channel->tx_ring)
+			break;
+
+		xgbe_prepare_tx_stop(pdata, channel);
+	}
+
 	/* Disable MAC Tx */
 	XGMAC_IOWRITE_BITS(pdata, MAC_TCR, TE, 0);
 
@@ -2569,6 +2649,15 @@ static void xgbe_powerdown_tx(struct xgbe_prv_data *pdata)
 	struct xgbe_channel *channel;
 	unsigned int i;
 
+	/* Prepare for Tx DMA channel stop */
+	channel = pdata->channel;
+	for (i = 0; i < pdata->channel_count; i++, channel++) {
+		if (!channel->tx_ring)
+			break;
+
+		xgbe_prepare_tx_stop(pdata, channel);
+	}
+
 	/* Disable MAC Tx */
 	XGMAC_IOWRITE_BITS(pdata, MAC_TCR, TE, 0);
 
@@ -2729,6 +2818,7 @@ void xgbe_init_function_ptrs_dev(struct xgbe_hw_if *hw_if)
 	hw_if->rx_desc_reset = xgbe_rx_desc_reset;
 	hw_if->is_last_desc = xgbe_is_last_desc;
 	hw_if->is_context_desc = xgbe_is_context_desc;
+	hw_if->tx_start_xmit = xgbe_tx_start_xmit;
 
 	/* For FLOW ctrl */
 	hw_if->config_tx_flow_control = xgbe_config_tx_flow_control;