ixgbe/base: fix Tx pending clearing

Wait for a last completion before clearing buffers,
and before proceeding, it needs make sure that the PCIe block does not have
transactions pending.

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
Acked-by: Jijiang Liu <jijiang.liu@intel.com>

diff --git a/lib/librte_pmd_ixgbe/ixgbe/ixgbe_common.c b/lib/librte_pmd_ixgbe/ixgbe/ixgbe_common.c
index 28eb3eb..ba5c8d8 100644 (file)
--- a/lib/librte_pmd_ixgbe/ixgbe/ixgbe_common.c
+++ b/lib/librte_pmd_ixgbe/ixgbe/ixgbe_common.c
@@ -4579,7 +4579,8 @@ void ixgbe_set_rxpba_generic(struct ixgbe_hw *hw, int num_pb, u32 headroom,
  **/
 void ixgbe_clear_tx_pending(struct ixgbe_hw *hw)
 {
-       u32 gcr_ext, hlreg0;
+       u32 gcr_ext, hlreg0, i, poll;
+       u16 value;
 
        /*
         * If double reset is not requested then all transactions should
@@ -4596,6 +4597,25 @@ void ixgbe_clear_tx_pending(struct ixgbe_hw *hw)
        hlreg0 = IXGBE_READ_REG(hw, IXGBE_HLREG0);
        IXGBE_WRITE_REG(hw, IXGBE_HLREG0, hlreg0 | IXGBE_HLREG0_LPBK);
 
+       /* Wait for a last completion before clearing buffers */
+       IXGBE_WRITE_FLUSH(hw);
+       msec_delay(3);
+
+       /*
+        * Before proceeding, make sure that the PCIe block does not have
+        * transactions pending.
+        */
+       poll = ixgbe_pcie_timeout_poll(hw);
+       for (i = 0; i < poll; i++) {
+               usec_delay(100);
+               value = IXGBE_READ_PCIE_WORD(hw, IXGBE_PCI_DEVICE_STATUS);
+               if (IXGBE_REMOVED(hw->hw_addr))
+                       goto out;
+               if (!(value & IXGBE_PCI_DEVICE_STATUS_TRANSACTION_PENDING))
+                       goto out;
+       }
+
+out:
        /* initiate cleaning flow for buffers in the PCIe transaction layer */
        gcr_ext = IXGBE_READ_REG(hw, IXGBE_GCR_EXT);
        IXGBE_WRITE_REG(hw, IXGBE_GCR_EXT,