+/*
+ * Stop Transmit Units for specified queue.
+ */
+int
+ixgbe_dev_tx_queue_stop(struct rte_eth_dev *dev, uint16_t tx_queue_id)
+{
+ struct ixgbe_hw *hw;
+ struct igb_tx_queue *txq;
+ uint32_t txdctl;
+ uint32_t txtdh, txtdt;
+ int poll_ms;
+
+ PMD_INIT_FUNC_TRACE();
+ hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+
+ if (tx_queue_id < dev->data->nb_tx_queues) {
+ txq = dev->data->tx_queues[tx_queue_id];
+
+ /* Wait until TX queue is empty */
+ if (hw->mac.type == ixgbe_mac_82599EB) {
+ poll_ms = RTE_IXGBE_REGISTER_POLL_WAIT_10_MS;
+ do {
+ rte_delay_us(RTE_IXGBE_WAIT_100_US);
+ txtdh = IXGBE_READ_REG(hw,
+ IXGBE_TDH(txq->reg_idx));
+ txtdt = IXGBE_READ_REG(hw,
+ IXGBE_TDT(txq->reg_idx));
+ } while (--poll_ms && (txtdh != txtdt));
+ if (!poll_ms)
+ PMD_INIT_LOG(ERR, "Tx Queue %d is not empty "
+ "when stopping.", tx_queue_id);
+ }
+
+ txdctl = IXGBE_READ_REG(hw, IXGBE_TXDCTL(txq->reg_idx));
+ txdctl &= ~IXGBE_TXDCTL_ENABLE;
+ IXGBE_WRITE_REG(hw, IXGBE_TXDCTL(txq->reg_idx), txdctl);
+
+ /* Wait until TX Enable ready */
+ if (hw->mac.type == ixgbe_mac_82599EB) {
+ poll_ms = RTE_IXGBE_REGISTER_POLL_WAIT_10_MS;
+ do {
+ rte_delay_ms(1);
+ txdctl = IXGBE_READ_REG(hw,
+ IXGBE_TXDCTL(txq->reg_idx));
+ } while (--poll_ms && (txdctl | IXGBE_TXDCTL_ENABLE));
+ if (!poll_ms)
+ PMD_INIT_LOG(ERR, "Could not disable "
+ "Tx Queue %d", tx_queue_id);
+ }
+
+ if (txq->ops != NULL) {
+ txq->ops->release_mbufs(txq);
+ txq->ops->reset(txq);
+ }
+ } else
+ return -1;
+
+ return 0;
+}