[Intel-wired-lan] [PATCH net 2/2] net: ixgbe: Use new IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING flag
Alexander Duyck
alexander.duyck at gmail.com
Wed Aug 16 18:17:29 UTC 2017
On Wed, Aug 16, 2017 at 2:41 AM, Ding Tianhong <dingtianhong at huawei.com> wrote:
> The ixgbe driver use the compile check to determine if it can
> send TLPs to Root Port with the Relaxed Ordering Attribute set,
> this is too inconvenient, now the new flag PCI_DEV_FLAGS_NO_RELAXED_ORDERING
> has been added to the kernel and we could check the bit4 in the PCIe
> Davice Control register to determine whether we should use the Relaxed
> Ordering Attributes or not, so we add a new flag which called
> IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING to the ixgbe driver, it will
> be set if the Root Port couldn't deal the upstream TLPs with Relaxed
> Ordering Attribute, then the driver could know what to do next.
>
> Signed-off-by: Ding Tianhong <dingtianhong at huawei.com>
I would say this is a good start but you probably don't even need the
IXGBE_FLAG2 bit. The hardware will honor the PCIe configuration space.
So I would just say you should probably drop the checks all together
and just strip the #ifdef CONFIG_SPARC bits. It should make the
resultant patch quite small and have the exact same effect.
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe.h | 1 +
> drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c | 37 ++++++++++++-------------
> drivers/net/ethernet/intel/ixgbe/ixgbe_common.c | 32 +++++++++++----------
> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 17 ++++++++++++
> 4 files changed, 53 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
> index dd55787..50e0553 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
> @@ -621,6 +621,7 @@ struct ixgbe_adapter {
> #define IXGBE_FLAG2_EEE_CAPABLE BIT(14)
> #define IXGBE_FLAG2_EEE_ENABLED BIT(15)
> #define IXGBE_FLAG2_RX_LEGACY BIT(16)
> +#define IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING BIT(17)
>
> /* Tx fast path data */
> int num_tx_queues;
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
> index 523f9d0..0727a30 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
> @@ -175,31 +175,30 @@ static s32 ixgbe_init_phy_ops_82598(struct ixgbe_hw *hw)
> **/
> static s32 ixgbe_start_hw_82598(struct ixgbe_hw *hw)
> {
> -#ifndef CONFIG_SPARC
> - u32 regval;
> - u32 i;
> -#endif
> + u32 regval, i;
> s32 ret_val;
> + struct ixgbe_adapter *adapter = hw->back;
>
> ret_val = ixgbe_start_hw_generic(hw);
>
> -#ifndef CONFIG_SPARC
> - /* Disable relaxed ordering */
> - for (i = 0; ((i < hw->mac.max_tx_queues) &&
> - (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
> - regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL(i));
> - regval &= ~IXGBE_DCA_TXCTRL_DESC_WRO_EN;
> - IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL(i), regval);
> - }
> + if (adapter->flags2 & IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING) {
> + /* Disable relaxed ordering */
> + for (i = 0; ((i < hw->mac.max_tx_queues) &&
> + (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
> + regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL(i));
> + regval &= ~IXGBE_DCA_TXCTRL_DESC_WRO_EN;
> + IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL(i), regval);
> + }
>
> - for (i = 0; ((i < hw->mac.max_rx_queues) &&
> - (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
> - regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
> - regval &= ~(IXGBE_DCA_RXCTRL_DATA_WRO_EN |
> - IXGBE_DCA_RXCTRL_HEAD_WRO_EN);
> - IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
> + for (i = 0; ((i < hw->mac.max_rx_queues) &&
> + (i < IXGBE_DCA_MAX_QUEUES_82598)); i++) {
> + regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
> + regval &= ~(IXGBE_DCA_RXCTRL_DATA_WRO_EN |
> + IXGBE_DCA_RXCTRL_HEAD_WRO_EN);
> + IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
> + }
> }
> -#endif
> +
> if (ret_val)
> return ret_val;
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> index d4933d2..2473c0b 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
> @@ -342,6 +342,7 @@ s32 ixgbe_start_hw_generic(struct ixgbe_hw *hw)
> s32 ixgbe_start_hw_gen2(struct ixgbe_hw *hw)
> {
> u32 i;
> + struct ixgbe_adapter *adapter = hw->back;
>
> /* Clear the rate limiters */
> for (i = 0; i < hw->mac.max_tx_queues; i++) {
> @@ -350,25 +351,26 @@ s32 ixgbe_start_hw_gen2(struct ixgbe_hw *hw)
> }
> IXGBE_WRITE_FLUSH(hw);
>
> -#ifndef CONFIG_SPARC
> - /* Disable relaxed ordering */
> - for (i = 0; i < hw->mac.max_tx_queues; i++) {
> - u32 regval;
> + if (adapter->flags2 & IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING) {
> + /* Disable relaxed ordering */
> + for (i = 0; i < hw->mac.max_tx_queues; i++) {
> + u32 regval;
>
> - regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL_82599(i));
> - regval &= ~IXGBE_DCA_TXCTRL_DESC_WRO_EN;
> - IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL_82599(i), regval);
> - }
> + regval = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL_82599(i));
> + regval &= ~IXGBE_DCA_TXCTRL_DESC_WRO_EN;
> + IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL_82599(i), regval);
> + }
>
> - for (i = 0; i < hw->mac.max_rx_queues; i++) {
> - u32 regval;
> + for (i = 0; i < hw->mac.max_rx_queues; i++) {
> + u32 regval;
>
> - regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
> - regval &= ~(IXGBE_DCA_RXCTRL_DATA_WRO_EN |
> - IXGBE_DCA_RXCTRL_HEAD_WRO_EN);
> - IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
> + regval = IXGBE_READ_REG(hw, IXGBE_DCA_RXCTRL(i));
> + regval &= ~(IXGBE_DCA_RXCTRL_DATA_WRO_EN |
> + IXGBE_DCA_RXCTRL_HEAD_WRO_EN);
> + IXGBE_WRITE_REG(hw, IXGBE_DCA_RXCTRL(i), regval);
> + }
> }
> -#endif
> +
> return 0;
> }
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> index f1dbdf2..f576be7 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
> @@ -10081,6 +10081,23 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> goto err_ioremap;
> }
>
> + /* If possible, we use PCIe Relaxed Ordering Attribute to deliver
> + * Ingress Packet Data to Free List Buffers in order to allow for
> + * chipset performance optimizations between the Root Complex and
> + * Memory Controllers. (Messages to the associated Ingress Queue
> + * notifying new Packet Placement in the Free Lists Buffers will be
> + * send without the Relaxed Ordering Attribute thus guaranteeing that
> + * all preceding PCIe Transaction Layer Packets will be processed
> + * first.) But some Root Complexes have various issues with Upstream
> + * Transaction Layer Packets with the Relaxed Ordering Attribute set.
> + * The PCIe devices which under the Root Complexes will be cleared the
> + * Relaxed Ordering bit in the configuration space, So we check our
> + * PCIe configuration space to see if it's flagged with advice against
> + * using Relaxed Ordering.
> + */
> + if (!pcie_relaxed_ordering_enabled(pdev))
> + adapter->flags2 |= IXGBE_FLAG2_ROOT_NO_RELAXED_ORDERING;
> +
> netdev->netdev_ops = &ixgbe_netdev_ops;
> ixgbe_set_ethtool_ops(netdev);
> netdev->watchdog_timeo = 5 * HZ;
> --
> 1.8.3.1
>
>
More information about the Intel-wired-lan
mailing list