[dpdk-users] How to get ixgbe vf port MAC address when ixgbe vf port bound to igb_uio but before dpdk app starts running?

[Vincent Li]

Hi,

I am attempting to make mTCP support ixgbevf
https://github.com/eunyoung14/mtcp/. here is briefly how mTCP work
with DPDK.

mTCP made a small changes to igb_uio.c to create a netdev interface in
Linux for packet statistics. when a NIC port bound to igb_uio, a
dpdk<#> interface will be created in Linux and the dpdk<#> interface
will have proper MAC address, this works for igb and ixgbe, the
igb_uio.c has not been changed to support ixgbevf, so once ixgbe vf
port is bound to igb_uio, the dpdk<#> interface get 00:00:00:00:00:00
MAC address.

the way it works for igb and ixgbe is code snippet below to read MAC
address from register:

/**
 * A device specific function that retrieves mac address from each NIC interface
 */
void
retrieve_dev_addr(struct net_device *netdev, struct net_adapter *adapter)
{
        struct ixgbe_hw *hw_i;
        struct e1000_hw *hw_e;
        //struct vmxnet3_hw *hw_x;
        u32 rar_high;
        u32 rar_low;
        u16 i;

        switch (adapter->type) {
        case IXGBE:
                hw_i = &adapter->hw._ixgbe_hw;
                rar_high = IXGBE_READ_REG(hw_i, IXGBE_RAH(0));
                rar_low = IXGBE_READ_REG(hw_i, IXGBE_RAL(0));

                for (i = 0; i < 4; i++)
                        netdev->dev_addr[i] = (u8)(rar_low >> (i*8));

                for (i = 0; i < 2; i++)
                        netdev->dev_addr[i+4] = (u8)(rar_high >> (i*8));
                break;
        case IGB:
                hw_e = &adapter->hw._e1000_hw;
                rar_high = E1000_READ_REG(hw_e, E1000_RAH(0));
                rar_low = E1000_READ_REG(hw_e, E1000_RAL(0));

                for (i = 0; i < E1000_RAL_MAC_ADDR_LEN; i++)
                        netdev->dev_addr[i] = (u8)(rar_low >> (i*8));

                for (i = 0; i < E1000_RAH_MAC_ADDR_LEN; i++)
                        netdev->dev_addr[i+4] = (u8)(rar_high >> (i*8));
                break;
        }

my question is IXGBE_READ_REG works for IXGBE VF port ?

I also see IXGBE VF PMD has function below:

/**
 *  ixgbe_get_mac_addr_vf - Read device MAC address
 *  @hw: pointer to the HW structure
 **/
s32 ixgbe_get_mac_addr_vf(struct ixgbe_hw *hw, u8 *mac_addr)
{
        int i;

        for (i = 0; i < IXGBE_ETH_LENGTH_OF_ADDRESS; i++)
                mac_addr[i] = hw->mac.perm_addr[i];

        return IXGBE_SUCCESS;
}

is the hw->mac.perm_addr populated when IXGBE VF port bound to igb_uio
? if so I could copy hw->mac.perm_addr to netdev-dev_addr[] for the
dpdk<#> interface. but I thought hw->mac.perm_addr may not be
populated when IXGBE_VF port bound to igb_uio, hw->mac.perm_addr is
populated when dpdk app start to run that include loading/initializing
the relevant dpdk PMD drivers. am I miss anything, any idea how this
can be achieved?

Regards,

Vincent