[PATCH v3 13/13] net/ngbe: restrict configuration of VLAN strip offload

[Jiawen Wu <jiawenwu@trustnetic.com>]

There is a hardware limitation that Rx ring config register is not
writable when Rx ring is enabled, i.e. the NGBE_RXCFG_ENA bit is set.
But disabling the ring when there is traffic will cause ring get stuck.
So restrict the configuration of VLAN strip offload only if device is
started.

Fixes: 59b46438fdaa ("net/ngbe: support VLAN offload and VLAN filter")
Cc: stable@dpdk.org

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
---
 drivers/net/ngbe/ngbe_ethdev.c | 49 ++++++++++++++--------------------
 1 file changed, 20 insertions(+), 29 deletions(-)

diff --git a/drivers/net/ngbe/ngbe_ethdev.c b/drivers/net/ngbe/ngbe_ethdev.c
index 325a9d1eaf..08e87471f6 100644
--- a/drivers/net/ngbe/ngbe_ethdev.c
+++ b/drivers/net/ngbe/ngbe_ethdev.c
@@ -586,41 +586,25 @@ ngbe_vlan_filter_set(struct rte_eth_dev *dev, uint16_t vlan_id, int on)
 }
 
 static void
-ngbe_vlan_strip_queue_set(struct rte_eth_dev *dev, uint16_t queue, int on)
+ngbe_vlan_strip_q_set(struct rte_eth_dev *dev, uint16_t queue, int on)
 {
-	struct ngbe_hw *hw = ngbe_dev_hw(dev);
-	struct ngbe_rx_queue *rxq;
-	bool restart;
-	uint32_t rxcfg, rxbal, rxbah;
-
 	if (on)
 		ngbe_vlan_hw_strip_enable(dev, queue);
 	else
 		ngbe_vlan_hw_strip_disable(dev, queue);
+}
 
-	rxq = dev->data->rx_queues[queue];
-	rxbal = rd32(hw, NGBE_RXBAL(rxq->reg_idx));
-	rxbah = rd32(hw, NGBE_RXBAH(rxq->reg_idx));
-	rxcfg = rd32(hw, NGBE_RXCFG(rxq->reg_idx));
-	if (rxq->offloads & RTE_ETH_RX_OFFLOAD_VLAN_STRIP) {
-		restart = (rxcfg & NGBE_RXCFG_ENA) &&
-			!(rxcfg & NGBE_RXCFG_VLAN);
-		rxcfg |= NGBE_RXCFG_VLAN;
-	} else {
-		restart = (rxcfg & NGBE_RXCFG_ENA) &&
-			(rxcfg & NGBE_RXCFG_VLAN);
-		rxcfg &= ~NGBE_RXCFG_VLAN;
-	}
-	rxcfg &= ~NGBE_RXCFG_ENA;
+static void
+ngbe_vlan_strip_queue_set(struct rte_eth_dev *dev, uint16_t queue, int on)
+{
+	struct ngbe_hw *hw = ngbe_dev_hw(dev);
 
-	if (restart) {
-		/* set vlan strip for ring */
-		ngbe_dev_rx_queue_stop(dev, queue);
-		wr32(hw, NGBE_RXBAL(rxq->reg_idx), rxbal);
-		wr32(hw, NGBE_RXBAH(rxq->reg_idx), rxbah);
-		wr32(hw, NGBE_RXCFG(rxq->reg_idx), rxcfg);
-		ngbe_dev_rx_queue_start(dev, queue);
+	if (!hw->adapter_stopped) {
+		PMD_DRV_LOG(ERR, "Please stop port first");
+		return;
 	}
+
+	ngbe_vlan_strip_q_set(dev, queue, on);
 }
 
 static int
@@ -846,9 +830,9 @@ ngbe_vlan_hw_strip_config(struct rte_eth_dev *dev)
 		rxq = dev->data->rx_queues[i];
 
 		if (rxq->offloads & RTE_ETH_RX_OFFLOAD_VLAN_STRIP)
-			ngbe_vlan_hw_strip_enable(dev, i);
+			ngbe_vlan_strip_q_set(dev, i, 1);
 		else
-			ngbe_vlan_hw_strip_disable(dev, i);
+			ngbe_vlan_strip_q_set(dev, i, 0);
 	}
 }
 
@@ -910,6 +894,13 @@ ngbe_vlan_offload_config(struct rte_eth_dev *dev, int mask)
 static int
 ngbe_vlan_offload_set(struct rte_eth_dev *dev, int mask)
 {
+	struct ngbe_hw *hw = ngbe_dev_hw(dev);
+
+	if (!hw->adapter_stopped && (mask & RTE_ETH_VLAN_STRIP_MASK)) {
+		PMD_DRV_LOG(ERR, "Please stop port first");
+		return -EPERM;
+	}
+
 	ngbe_config_vlan_strip_on_all_queues(dev, mask);
 
 	ngbe_vlan_offload_config(dev, mask);
-- 
2.27.0