[dpdk-dev] [PATCH v2] net/ixgbe: fix fdirctrl register setting

[dapengx.yu@intel.com]

From: YU DAPENG <dapengx.yu@intel.com>

The function ixgbe_fdir_set_flexbytes_offset is used when create FDir
rule for flexbytes. It set a register: FDIRCTRL.FLEX_OFFSET, which
cause that even if the FDir flexbytes rule is destroyed, the rule still
direct the packet and transfer it to the wrong place. It is because
setting FDIRCTRL shall only be permitted on Flow Director
initialization flow or clearing the Flow Director table according to
intel datasheet, otherwise unexpected happens. In order to evade the
limit, add code to set FDIRCMD.CLEARHT to 1b and then clear it back to
0b to make the setting act like the Flow Director initialization flow
or clearing the Flow Director table.

Fixes: f35fec63dde1 ("net/ixgbe: enable flex bytes for generic flow API")
Cc: stable@dpdk.org

Signed-off-by: YU DAPENG <dapengx.yu@intel.com>
---
 drivers/net/ixgbe/ixgbe_fdir.c | 29 +++++++++++++++++++++++++++++
 drivers/net/ixgbe/ixgbe_flow.c | 15 ++++++++-------
 2 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_fdir.c b/drivers/net/ixgbe/ixgbe_fdir.c
index a0fab5070..11b9effeb 100644
--- a/drivers/net/ixgbe/ixgbe_fdir.c
+++ b/drivers/net/ixgbe/ixgbe_fdir.c
@@ -503,9 +503,30 @@ ixgbe_fdir_set_flexbytes_offset(struct rte_eth_dev *dev,
 				uint16_t offset)
 {
 	struct ixgbe_hw *hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	struct ixgbe_hw_fdir_info *fdir_info =
+		IXGBE_DEV_PRIVATE_TO_FDIR_INFO(dev->data->dev_private);
 	uint32_t fdirctrl;
 	int i;
 
+	if (fdir_info->flex_bytes_offset == offset)
+		return 0;
+
+	/**
+	 * 82599 adapters flow director init flow cannot be restarted,
+	 * Workaround 82599 silicon errata by performing the following steps
+	 * before re-writing the FDIRCTRL control register with the same value.
+	 * - write 1 to bit 8 of FDIRCMD register &
+	 * - write 0 to bit 8 of FDIRCMD register
+	 */
+	IXGBE_WRITE_REG(hw, IXGBE_FDIRCMD,
+			(IXGBE_READ_REG(hw, IXGBE_FDIRCMD) |
+			 IXGBE_FDIRCMD_CLEARHT));
+	IXGBE_WRITE_FLUSH(hw);
+	IXGBE_WRITE_REG(hw, IXGBE_FDIRCMD,
+			(IXGBE_READ_REG(hw, IXGBE_FDIRCMD) &
+			 ~IXGBE_FDIRCMD_CLEARHT));
+	IXGBE_WRITE_FLUSH(hw);
+
 	fdirctrl = IXGBE_READ_REG(hw, IXGBE_FDIRCTRL);
 
 	fdirctrl &= ~IXGBE_FDIRCTRL_FLEX_MASK;
@@ -520,6 +541,14 @@ ixgbe_fdir_set_flexbytes_offset(struct rte_eth_dev *dev,
 			break;
 		msec_delay(1);
 	}
+
+	if (i >= IXGBE_FDIR_INIT_DONE_POLL) {
+		PMD_DRV_LOG(ERR, "Flow Director poll time exceeded!");
+		return -ETIMEDOUT;
+	}
+
+	fdir_info->flex_bytes_offset = offset;
+
 	return 0;
 }
 
diff --git a/drivers/net/ixgbe/ixgbe_flow.c b/drivers/net/ixgbe/ixgbe_flow.c
index 39f6ed73f..9aeb2e4a4 100644
--- a/drivers/net/ixgbe/ixgbe_flow.c
+++ b/drivers/net/ixgbe/ixgbe_flow.c
@@ -3137,13 +3137,13 @@ ixgbe_flow_create(struct rte_eth_dev *dev,
 				rte_memcpy(&fdir_info->mask,
 					&fdir_rule.mask,
 					sizeof(struct ixgbe_hw_fdir_mask));
-				fdir_info->flex_bytes_offset =
-					fdir_rule.flex_bytes_offset;
 
-				if (fdir_rule.mask.flex_bytes_mask)
-					ixgbe_fdir_set_flexbytes_offset(dev,
+				if (fdir_rule.mask.flex_bytes_mask) {
+					ret = ixgbe_fdir_set_flexbytes_offset(dev,
 						fdir_rule.flex_bytes_offset);
-
+					if (ret)
+						goto out;
+				}
 				ret = ixgbe_fdir_set_input_mask(dev);
 				if (ret)
 					goto out;
@@ -3161,8 +3161,9 @@ ixgbe_flow_create(struct rte_eth_dev *dev,
 				if (ret)
 					goto out;
 
-				if (fdir_info->flex_bytes_offset !=
-						fdir_rule.flex_bytes_offset)
+				if (fdir_rule.mask.flex_bytes_mask &&
+				    fdir_info->flex_bytes_offset !=
+				    fdir_rule.flex_bytes_offset)
 					goto out;
 			}
 		}
-- 
2.26.2.windows.1