PHY driver configuration
------------------------
MvPhyDxe provides basic initialization and status routines for Marvell PHYs.
Currently only 1512 series PHYs are supported. Following PCDs are required:

  gMarvellTokenSpaceGuid.PcdPhyConnectionTypes
  (list of values corresponding to PHY_CONNECTION enum)
  gMarvellTokenSpaceGuid.PcdPhyStartupAutoneg
  (boolean - if true, driver waits for autonegotiation on startup)
  gMarvellTokenSpaceGuid.PcdPhyDeviceIds
  (list of values corresponding to MV_PHY_DEVICE_ID enum)

PHY_CONNECTION enum type is defined as follows:

  typedef enum {
0    PHY_CONNECTION_RGMII,
1    PHY_CONNECTION_RGMII_ID,
2    PHY_CONNECTION_RGMII_TXID,
3    PHY_CONNECTION_RGMII_RXID,
4    PHY_CONNECTION_SGMII,
5    PHY_CONNECTION_RTBI,
6    PHY_CONNECTION_XAUI,
7    PHY_CONNECTION_RXAUI
  } PHY_CONNECTION;

MV_PHY_DEVICE_ID:

  typedef enum {
0    MV_PHY_DEVICE_1512,
  } MV_PHY_DEVICE_ID;

It should be extended when adding support for other PHY
models.

Thus in order to set RGMII for 1st PHY and SGMII for 2nd, PCD should be:

  gMarvellTokenSpaceGuid.PcdPhyConnectionTypes|{ 0x0, 0x4 }

with disabled autonegotiation:

  gMarvellTokenSpaceGuid.PcdPhyStartupAutoneg|FALSE

assuming, that PHY models are 1512:

  gMarvellTokenSpaceGuid.PcdPhyDeviceIds|{ 0x0, 0x0 }