Starterware: AM335x Ethernet fails in U-boot

Tool/software: Starterware

HI all:

I have a custom board which main chip is am3352, the ethernet PHY is Ti-DP83848K as same as Ti-am335x starter-kit, and in my board the PHY's interface is RMII.

1. Now, I went into the u-boot command mode, I can detect  all the PHY by command: " mii info ", but cannot "ping" anything.

2. I enable the "loopback" register, also cannot ping anything.

3. So I think maybe the MAC and PHY has something wrong, different from Ti-am335x starter-kit, my PHY's interface is RMII

so I modify all the code about PHY's interface defined, and the pin_mux: board/ti/am335x/mux.c

which is defined:

static struct module_pin_mux rmii1_pin_mux[] = {                                                                                                             
    {OFFSET(mdio_clk), MODE(0) | PULLUP_EN},    /* MDIO_CLK */
    {OFFSET(mdio_data), MODE(0) | RXACTIVE | PULLUP_EN}, /* MDIO_DATA */
    {OFFSET(mii1_crs), MODE(1) | RXACTIVE},     /* MII1_CRS */
    {OFFSET(mii1_rxerr), MODE(1) | RXACTIVE},   /* MII1_RXERR */
    {OFFSET(mii1_txen), MODE(1)},           /* MII1_TXEN */
    {OFFSET(mii1_txd1), MODE(1)},           /* MII1_TXD1 */
    {OFFSET(mii1_txd0), MODE(1)},           /* MII1_TXD0 */
    {OFFSET(mii1_rxd1), MODE(1) | RXACTIVE},    /* MII1_RXD1 */
    {OFFSET(mii1_rxd0), MODE(1) | RXACTIVE},    /* MII1_RXD0 */
    {OFFSET(rmii1_refclk), MODE(0) | RXACTIVE}, /* RMII1_REFCLK */
    {-1},
};

I dont understand what it is, here is my board's diagram: Should I modify it?