From 71bde60191a9fa44d33b582c5e3713ffe99b0fef Mon Sep 17 00:00:00 2001 From: Don Skidmore Date: Wed, 29 Oct 2014 07:23:41 +0000 Subject: [PATCH] ixgbe: fix X540 Completion timeout On topologies including few levels of PCIe switching X540 can run into an unexpected completion error. We get around this by waiting after enabling loopback a sufficient amount of time until Tx Data Fetch is sent. We then poll the pending transaction bit to ensure we received the completion. Only then do we go on to clear the buffers. Signed-of-by: Don Skidmore Tested-by: Phil Schmitt Signed-off-by: Jeff Kirsher --- .../net/ethernet/intel/ixgbe/ixgbe_common.c | 20 ++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c index b5f484bf3fd..04067087618 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c @@ -3583,7 +3583,8 @@ s32 ixgbe_set_fw_drv_ver_generic(struct ixgbe_hw *hw, u8 maj, u8 min, **/ 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 @@ -3600,6 +3601,23 @@ 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); + usleep_range(3000, 6000); + + /* 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++) { + usleep_range(100, 200); + value = ixgbe_read_pci_cfg_word(hw, IXGBE_PCI_DEVICE_STATUS); + if (ixgbe_removed(hw->hw_addr)) + break; + if (!(value & IXGBE_PCI_DEVICE_STATUS_TRANSACTION_PENDING)) + break; + } + /* 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, -- 2.46.0