[dpdk-stable] [PATCH v3] net/ixgbe: fix flow ctrl mode setting

[Guinan Sun <guinanx.sun@intel.com>]

When the port starts, the hw register is reset first,
and then the required parameters are set again.
If the parameters to be used are not set after resetting the register,
a read register error will occur. This patch is used to fix the problem.

Fixes: af75078fece3 ("first public release")
Cc: stable@dpdk.org

Signed-off-by: Guinan Sun <guinanx.sun@intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 76 +++++++++++++++++++++-----------
 drivers/net/ixgbe/ixgbe_ethdev.h |  1 +
 2 files changed, 51 insertions(+), 26 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 2a248a3f2..b3d6e9494 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -1173,8 +1173,8 @@ eth_ixgbe_dev_init(struct rte_eth_dev *eth_dev, void *init_params __rte_unused)
 	memset(dcb_config, 0, sizeof(struct ixgbe_dcb_config));
 	ixgbe_dcb_init(hw, dcb_config);
 	/* Get Hardware Flow Control setting */
-	hw->fc.requested_mode = ixgbe_fc_full;
-	hw->fc.current_mode = ixgbe_fc_full;
+	hw->fc.requested_mode = ixgbe_fc_none;
+	hw->fc.current_mode = ixgbe_fc_none;
 	hw->fc.pause_time = IXGBE_FC_PAUSE;
 	for (i = 0; i < IXGBE_DCB_MAX_TRAFFIC_CLASS; i++) {
 		hw->fc.low_water[i] = IXGBE_FC_LO;
@@ -2533,6 +2533,39 @@ ixgbe_set_vf_rate_limit(struct rte_eth_dev *dev, uint16_t vf,
 	return 0;
 }
 
+static int
+ixgbe_flow_ctrl_enable(struct rte_eth_dev *dev, struct ixgbe_hw *hw)
+{
+	struct ixgbe_adapter *adapter = dev->data->dev_private;
+	int err;
+	uint32_t mflcn;
+
+	err = ixgbe_fc_enable(hw);
+
+	/* Not negotiated is not an error case */
+	if (err == IXGBE_SUCCESS || err == IXGBE_ERR_FC_NOT_NEGOTIATED) {
+		/*
+		 *check if we want to forward MAC frames - driver doesn't
+		 *have native capability to do that,
+		 *so we'll write the registers ourselves
+		 */
+
+		mflcn = IXGBE_READ_REG(hw, IXGBE_MFLCN);
+
+		/* set or clear MFLCN.PMCF bit depending on configuration */
+		if (adapter->mac_ctrl_frame_fwd != 0)
+			mflcn |= IXGBE_MFLCN_PMCF;
+		else
+			mflcn &= ~IXGBE_MFLCN_PMCF;
+
+		IXGBE_WRITE_REG(hw, IXGBE_MFLCN, mflcn);
+		IXGBE_WRITE_FLUSH(hw);
+
+		return 0;
+	}
+	return err;
+}
+
 /*
  * Configure device link speed and setup link.
  * It returns 0 on success.
@@ -2659,6 +2692,12 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
 
 	ixgbe_restore_statistics_mapping(dev);
 
+	err = ixgbe_flow_ctrl_enable(dev, hw);
+	if (err < 0) {
+		PMD_INIT_LOG(ERR, "enable flow ctrl err");
+		goto error;
+	}
+
 	err = ixgbe_dev_rxtx_start(dev);
 	if (err < 0) {
 		PMD_INIT_LOG(ERR, "Unable to start rxtx queues");
@@ -2895,6 +2934,8 @@ ixgbe_dev_stop(struct rte_eth_dev *dev)
 
 	adapter->rss_reta_updated = 0;
 
+	adapter->mac_ctrl_frame_fwd = 0;
+
 	hw->adapter_stopped = true;
 }
 
@@ -4684,10 +4725,10 @@ static int
 ixgbe_flow_ctrl_set(struct rte_eth_dev *dev, struct rte_eth_fc_conf *fc_conf)
 {
 	struct ixgbe_hw *hw;
+	struct ixgbe_adapter *adapter = dev->data->dev_private;
 	int err;
 	uint32_t rx_buf_size;
 	uint32_t max_high_water;
-	uint32_t mflcn;
 	enum ixgbe_fc_mode rte_fcmode_2_ixgbe_fcmode[] = {
 		ixgbe_fc_none,
 		ixgbe_fc_rx_pause,
@@ -4720,31 +4761,14 @@ ixgbe_flow_ctrl_set(struct rte_eth_dev *dev, struct rte_eth_fc_conf *fc_conf)
 	hw->fc.low_water[0]   = fc_conf->low_water;
 	hw->fc.send_xon       = fc_conf->send_xon;
 	hw->fc.disable_fc_autoneg = !fc_conf->autoneg;
+	adapter->mac_ctrl_frame_fwd = fc_conf->mac_ctrl_frame_fwd;
 
-	err = ixgbe_fc_enable(hw);
-
-	/* Not negotiated is not an error case */
-	if ((err == IXGBE_SUCCESS) || (err == IXGBE_ERR_FC_NOT_NEGOTIATED)) {
-
-		/* check if we want to forward MAC frames - driver doesn't have native
-		 * capability to do that, so we'll write the registers ourselves */
-
-		mflcn = IXGBE_READ_REG(hw, IXGBE_MFLCN);
-
-		/* set or clear MFLCN.PMCF bit depending on configuration */
-		if (fc_conf->mac_ctrl_frame_fwd != 0)
-			mflcn |= IXGBE_MFLCN_PMCF;
-		else
-			mflcn &= ~IXGBE_MFLCN_PMCF;
-
-		IXGBE_WRITE_REG(hw, IXGBE_MFLCN, mflcn);
-		IXGBE_WRITE_FLUSH(hw);
-
-		return 0;
+	err = ixgbe_flow_ctrl_enable(dev, hw);
+	if (err < 0) {
+		PMD_INIT_LOG(ERR, "ixgbe_flow_ctrl_enable = 0x%x", err);
+		return -EIO;
 	}
-
-	PMD_INIT_LOG(ERR, "ixgbe_fc_enable = 0x%x", err);
-	return -EIO;
+	return err;
 }
 
 /**
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
index e1cd8fd16..d309813da 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.h
+++ b/drivers/net/ixgbe/ixgbe_ethdev.h
@@ -511,6 +511,7 @@ struct ixgbe_adapter {
 	 * mailbox status) link status.
 	 */
 	uint8_t pflink_fullchk;
+	uint8_t mac_ctrl_frame_fwd;
 };
 
 struct ixgbe_vf_representor {
-- 
2.17.1