[dpdk-dev] [PATCH] i40e: fix the write back issue in FVL VF

[Jingjing Wu <jingjing.wu@intel.com>]

If DPDK is used on VF while the host is using Linux Kernel driver
as PF driver on FVL NIC, then VF Rx is reported only in batches of
4 packets. It is due to the kernel driver assumes VF driver is working
in interrupt mode, but DPDK VF is working in Polling mode.
This patch fixes this issue by using the V1.1 virtual channel with
Linux i40e PF driver.

Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
---
 drivers/net/i40e/i40e_ethdev.h    |  5 +++
 drivers/net/i40e/i40e_ethdev_vf.c | 66 +++++++++++++++++++++++++++++----------
 2 files changed, 54 insertions(+), 17 deletions(-)

diff --git a/drivers/net/i40e/i40e_ethdev.h b/drivers/net/i40e/i40e_ethdev.h
index 6185657..d42487d 100644
--- a/drivers/net/i40e/i40e_ethdev.h
+++ b/drivers/net/i40e/i40e_ethdev.h
@@ -91,6 +91,11 @@
 #define I40E_48_BIT_WIDTH (CHAR_BIT * 6)
 #define I40E_48_BIT_MASK  RTE_LEN2MASK(I40E_48_BIT_WIDTH, uint64_t)
 
+/* Linux PF host with virtchnl version 1.1 */
+#define PF_IS_V11(vf) \
+	(((vf)->version_major == I40E_VIRTCHNL_VERSION_MAJOR) && \
+	((vf)->version_minor == 1))
+
 /* index flex payload per layer */
 enum i40e_flxpld_layer_idx {
 	I40E_FLXPLD_L2_IDX    = 0,
diff --git a/drivers/net/i40e/i40e_ethdev_vf.c b/drivers/net/i40e/i40e_ethdev_vf.c
index b694400..176a2f6 100644
--- a/drivers/net/i40e/i40e_ethdev_vf.c
+++ b/drivers/net/i40e/i40e_ethdev_vf.c
@@ -67,7 +67,8 @@
 #include "i40e_rxtx.h"
 #include "i40e_ethdev.h"
 #include "i40e_pf.h"
-#define I40EVF_VSI_DEFAULT_MSIX_INTR 1
+#define I40EVF_VSI_DEFAULT_MSIX_INTR     1
+#define I40EVF_VSI_DEFAULT_MSIX_INTR_LNX 0
 
 /* busy wait delay in msec */
 #define I40EVF_BUSY_WAIT_DELAY 10
@@ -412,7 +413,7 @@ i40evf_check_api_version(struct rte_eth_dev *dev)
 	if (vf->version_major == I40E_DPDK_VERSION_MAJOR)
 		PMD_DRV_LOG(INFO, "Peer is DPDK PF host");
 	else if ((vf->version_major == I40E_VIRTCHNL_VERSION_MAJOR) &&
-		(vf->version_minor == I40E_VIRTCHNL_VERSION_MINOR))
+		(vf->version_minor <= I40E_VIRTCHNL_VERSION_MINOR))
 		PMD_DRV_LOG(INFO, "Peer is Linux PF host");
 	else {
 		PMD_INIT_LOG(ERR, "PF/VF API version mismatch:(%u.%u)-(%u.%u)",
@@ -432,14 +433,23 @@ i40evf_get_vf_resource(struct rte_eth_dev *dev)
 	struct i40e_vf *vf = I40EVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
 	int err;
 	struct vf_cmd_info args;
-	uint32_t len;
+	uint32_t caps, len;
 
 	args.ops = I40E_VIRTCHNL_OP_GET_VF_RESOURCES;
-	args.in_args = NULL;
-	args.in_args_size = 0;
 	args.out_buffer = cmd_result_buffer;
 	args.out_size = I40E_AQ_BUF_SZ;
-
+	if (PF_IS_V11(vf)) {
+		caps = I40E_VIRTCHNL_VF_OFFLOAD_L2 |
+		       I40E_VIRTCHNL_VF_OFFLOAD_RSS_AQ |
+		       I40E_VIRTCHNL_VF_OFFLOAD_RSS_REG |
+		       I40E_VIRTCHNL_VF_OFFLOAD_VLAN |
+		       I40E_VIRTCHNL_VF_OFFLOAD_RX_POLLING;
+		args.in_args = (uint8_t *)&caps;
+		args.in_args_size = sizeof(caps);
+	} else {
+		args.in_args = NULL;
+		args.in_args_size = 0;
+	}
 	err = i40evf_execute_vf_cmd(dev, &args);
 
 	if (err) {
@@ -692,6 +702,8 @@ i40evf_configure_queues(struct rte_eth_dev *dev)
 		return i40evf_configure_vsi_queues(dev);
 }
 
+#define I40E_QINT_RQCTL_MSIX_INDX_NOITR     3
+
 static int
 i40evf_config_irq_map(struct rte_eth_dev *dev)
 {
@@ -703,11 +715,14 @@ i40evf_config_irq_map(struct rte_eth_dev *dev)
 	int i, err;
 	map_info = (struct i40e_virtchnl_irq_map_info *)cmd_buffer;
 	map_info->num_vectors = 1;
-	map_info->vecmap[0].rxitr_idx = RTE_LIBRTE_I40E_ITR_INTERVAL / 2;
-	map_info->vecmap[0].txitr_idx = RTE_LIBRTE_I40E_ITR_INTERVAL / 2;
+	map_info->vecmap[0].rxitr_idx = I40E_QINT_RQCTL_MSIX_INDX_NOITR;
 	map_info->vecmap[0].vsi_id = vf->vsi_res->vsi_id;
 	/* Alway use default dynamic MSIX interrupt */
-	map_info->vecmap[0].vector_id = I40EVF_VSI_DEFAULT_MSIX_INTR;
+	if (vf->version_major == I40E_DPDK_VERSION_MAJOR)
+		map_info->vecmap[0].vector_id = I40EVF_VSI_DEFAULT_MSIX_INTR;
+	else
+		map_info->vecmap[0].vector_id = I40EVF_VSI_DEFAULT_MSIX_INTR_LNX;
+
 	/* Don't map any tx queue */
 	map_info->vecmap[0].txq_map = 0;
 	map_info->vecmap[0].rxq_map = 0;
@@ -1546,18 +1561,37 @@ i40evf_tx_init(struct rte_eth_dev *dev)
 }
 
 static inline void
-i40evf_enable_queues_intr(struct i40e_hw *hw)
+i40evf_enable_queues_intr(struct rte_eth_dev *dev)
 {
-	I40E_WRITE_REG(hw, I40E_VFINT_DYN_CTLN1(I40EVF_VSI_DEFAULT_MSIX_INTR - 1),
+	struct i40e_vf *vf = I40EVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
+	struct i40e_hw *hw = I40E_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+
+	if (vf->version_major == I40E_DPDK_VERSION_MAJOR)
+		/* To support DPDK PF host */
+		I40E_WRITE_REG(hw,
+			I40E_VFINT_DYN_CTLN1(I40EVF_VSI_DEFAULT_MSIX_INTR - 1),
 			I40E_VFINT_DYN_CTLN1_INTENA_MASK |
 			I40E_VFINT_DYN_CTLN_CLEARPBA_MASK);
+	else
+		/* To support Linux PF host */
+		I40E_WRITE_REG(hw, I40E_VFINT_DYN_CTL01,
+				I40E_VFINT_DYN_CTL01_INTENA_MASK |
+				I40E_VFINT_DYN_CTL01_CLEARPBA_MASK);
 }
 
 static inline void
-i40evf_disable_queues_intr(struct i40e_hw *hw)
+i40evf_disable_queues_intr(struct rte_eth_dev *dev)
 {
-	I40E_WRITE_REG(hw, I40E_VFINT_DYN_CTLN1(I40EVF_VSI_DEFAULT_MSIX_INTR - 1),
+	struct i40e_vf *vf = I40EVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
+	struct i40e_hw *hw = I40E_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+
+	if (vf->version_major == I40E_DPDK_VERSION_MAJOR)
+		I40E_WRITE_REG(hw,
+			I40E_VFINT_DYN_CTLN1(I40EVF_VSI_DEFAULT_MSIX_INTR - 1),
 			0);
+	else
+		I40E_WRITE_REG(hw, I40E_VFINT_DYN_CTL01, 0);
+
 }
 
 static int
@@ -1604,7 +1638,7 @@ i40evf_dev_start(struct rte_eth_dev *dev)
 		goto err_mac;
 	}
 
-	i40evf_enable_queues_intr(hw);
+	i40evf_enable_queues_intr(dev);
 	return 0;
 
 err_mac:
@@ -1616,11 +1650,9 @@ err_queue:
 static void
 i40evf_dev_stop(struct rte_eth_dev *dev)
 {
-	struct i40e_hw *hw = I40E_DEV_PRIVATE_TO_HW(dev->data->dev_private);
-
 	PMD_INIT_FUNC_TRACE();
 
-	i40evf_disable_queues_intr(hw);
+	i40evf_disable_queues_intr(dev);
 	i40evf_stop_queues(dev);
 	i40e_dev_clear_queues(dev);
 }
-- 
2.4.0