[dpdk-dev] [PATCH v5] net/ice: simplify the use of DCF device reset

[dapengx.yu@intel.com]

From: Dapeng Yu <dapengx.yu@intel.com>

After DCF is reset by PF, the DCF device un-initialization cannot
function normally since the kernel may not clean up resource.

This patch detects the reset flag, which is set by PF on DCF reset,
if the flag is true, reset hw to trigger an additional DCF
enable/disable cycle which helps to work around the issue that kernel
driver may not clean up resource during previous reset.

Fixes: 1a86f4dbdf42 ("net/ice: support DCF device reset")
Cc: stable@dpdk.org

Signed-off-by: Dapeng Yu <dapengx.yu@intel.com>
---
V2:
* Ignore the returned error of dev_uninit when DCF is reset by PF
V3:
* Add a reset function to re-initialize AdminQ resource
* Add a function to check the reset flag
V4:
* Remove redundant reset flag setting
V5:
* Rename function and modify comments
---
 drivers/net/ice/ice_dcf.c        |  2 ++
 drivers/net/ice/ice_dcf_ethdev.c | 34 +++++++++++++++++++++++++++++++-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ice/ice_dcf.c b/drivers/net/ice/ice_dcf.c
index 084f7a53db..366ff0a907 100644
--- a/drivers/net/ice/ice_dcf.c
+++ b/drivers/net/ice/ice_dcf.c
@@ -593,6 +593,8 @@ ice_dcf_init_hw(struct rte_eth_dev *eth_dev, struct ice_dcf_hw *hw)
 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(eth_dev);
 	int ret, size;
 
+	hw->resetting = false;
+
 	hw->avf.hw_addr = pci_dev->mem_resource[0].addr;
 	hw->avf.back = hw;
 
diff --git a/drivers/net/ice/ice_dcf_ethdev.c b/drivers/net/ice/ice_dcf_ethdev.c
index 7c71a48010..4d9484e994 100644
--- a/drivers/net/ice/ice_dcf_ethdev.c
+++ b/drivers/net/ice/ice_dcf_ethdev.c
@@ -1025,11 +1025,44 @@ ice_dcf_tm_ops_get(struct rte_eth_dev *dev __rte_unused,
 	return 0;
 }
 
+static inline void
+ice_dcf_reset_hw(struct rte_eth_dev *eth_dev, struct ice_dcf_hw *hw)
+{
+	ice_dcf_uninit_hw(eth_dev, hw);
+	ice_dcf_init_hw(eth_dev, hw);
+}
+
+/* Check if reset has been triggered by PF */
+static inline bool
+ice_dcf_is_reset(struct rte_eth_dev *dev)
+{
+	struct ice_dcf_adapter *ad = dev->data->dev_private;
+	struct iavf_hw *hw = &ad->real_hw.avf;
+
+	return !(IAVF_READ_REG(hw, IAVF_VF_ARQLEN1) &
+		 IAVF_VF_ARQLEN1_ARQENABLE_MASK);
+}
+
 static int
 ice_dcf_dev_reset(struct rte_eth_dev *dev)
 {
+	struct ice_dcf_adapter *ad = dev->data->dev_private;
+	struct ice_dcf_hw *hw = &ad->real_hw;
 	int ret;
 
+	if (ice_dcf_is_reset(dev)) {
+		if (!ad->real_hw.resetting)
+			ad->real_hw.resetting = true;
+		PMD_DRV_LOG(ERR, "The DCF has been reset by PF");
+
+		/*
+		 * Simply reset hw to trigger an additional DCF enable/disable
+		 * cycle which help to workaround the issue that kernel driver
+		 * may not clean up resource during previous reset.
+		 */
+		ice_dcf_reset_hw(dev, hw);
+	}
+
 	ret = ice_dcf_dev_uninit(dev);
 	if (ret)
 		return ret;
@@ -1072,7 +1105,6 @@ ice_dcf_dev_init(struct rte_eth_dev *eth_dev)
 {
 	struct ice_dcf_adapter *adapter = eth_dev->data->dev_private;
 
-	adapter->real_hw.resetting = false;
 	eth_dev->dev_ops = &ice_dcf_eth_dev_ops;
 	eth_dev->rx_pkt_burst = ice_dcf_recv_pkts;
 	eth_dev->tx_pkt_burst = ice_dcf_xmit_pkts;
-- 
2.27.0