amd-xgbe: Update how to determine DMA channel status

Tx and Rx DMA channel status determiniation is different depending on the
version of the hardware. Update the channel status processing code to
account for the change.  Also, reduce the timeout value used when stopping
the channels.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 38 insertions, 20 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
index fbd60ee0260b..0a7ab63deaf9 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-dev.c
@@ -2944,20 +2944,48 @@ static void xgbe_config_mmc(struct xgbe_prv_data *pdata)
 	XGMAC_IOWRITE_BITS(pdata, MMC_CR, CR, 1);
 }
 
+static void xgbe_txq_prepare_tx_stop(struct xgbe_prv_data *pdata,
+				     unsigned int queue)
+{
+	unsigned int tx_status;
+	unsigned long tx_timeout;
+
+	/* The Tx engine cannot be stopped if it is actively processing
+	 * packets. Wait for the Tx queue to empty the Tx fifo.  Don't
+	 * wait forever though...
+	 */
+	tx_timeout = jiffies + (XGBE_DMA_STOP_TIMEOUT * HZ);
+	while (time_before(jiffies, tx_timeout)) {
+		tx_status = XGMAC_MTL_IOREAD(pdata, queue, MTL_Q_TQDR);
+		if ((XGMAC_GET_BITS(tx_status, MTL_Q_TQDR, TRCSTS) != 1) &&
+		    (XGMAC_GET_BITS(tx_status, MTL_Q_TQDR, TXQSTS) == 0))
+			break;
+
+		usleep_range(500, 1000);
+	}
+
+	if (!time_before(jiffies, tx_timeout))
+		netdev_info(pdata->netdev,
+			    "timed out waiting for Tx queue %u to empty\n",
+			    queue);
+}
+
 static void xgbe_prepare_tx_stop(struct xgbe_prv_data *pdata,
-				 struct xgbe_channel *channel)
+				 unsigned int queue)
 {
 	unsigned int tx_dsr, tx_pos, tx_qidx;
 	unsigned int tx_status;
 	unsigned long tx_timeout;
 
+	if (XGMAC_GET_BITS(pdata->hw_feat.version, MAC_VR, SNPSVER) > 0x20)
+		return xgbe_txq_prepare_tx_stop(pdata, queue);
+
 	/* Calculate the status register to read and the position within */
-	if (channel->queue_index < DMA_DSRX_FIRST_QUEUE) {
+	if (queue < DMA_DSRX_FIRST_QUEUE) {
 		tx_dsr = DMA_DSR0;
-		tx_pos = (channel->queue_index * DMA_DSR_Q_WIDTH) +
-			 DMA_DSR0_TPS_START;
+		tx_pos = (queue * DMA_DSR_Q_WIDTH) + DMA_DSR0_TPS_START;
 	} else {
-		tx_qidx = channel->queue_index - DMA_DSRX_FIRST_QUEUE;
+		tx_qidx = queue - 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) +
@@ -2982,7 +3010,7 @@ static void xgbe_prepare_tx_stop(struct xgbe_prv_data *pdata,
 	if (!time_before(jiffies, tx_timeout))
 		netdev_info(pdata->netdev,
 			    "timed out waiting for Tx DMA channel %u to stop\n",
-			    channel->queue_index);
+			    queue);
 }
 
 static void xgbe_enable_tx(struct xgbe_prv_data *pdata)
@@ -3014,13 +3042,8 @@ static void xgbe_disable_tx(struct xgbe_prv_data *pdata)
 	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);
-	}
+	for (i = 0; i < pdata->tx_q_count; i++)
+		xgbe_prepare_tx_stop(pdata, i);
 
 	/* Disable MAC Tx */
 	XGMAC_IOWRITE_BITS(pdata, MAC_TCR, TE, 0);
@@ -3144,13 +3167,8 @@ static void xgbe_powerdown_tx(struct xgbe_prv_data *pdata)
 	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);
-	}
+	for (i = 0; i < pdata->tx_q_count; i++)
+		xgbe_prepare_tx_stop(pdata, i);
 
 	/* Disable MAC Tx */
 	XGMAC_IOWRITE_BITS(pdata, MAC_TCR, TE, 0);