XMAC_XIF_SEL_POR_CLK_SRC
val |= XMAC_XIF_SEL_POR_CLK_SRC;
val &= ~XMAC_XIF_SEL_POR_CLK_SRC;
val &= ~XMAC_XIF_SEL_POR_CLK_SRC;
val |= XMAC_XIF_SEL_POR_CLK_SRC;
val &= ~XMAC_XIF_SEL_POR_CLK_SRC;
val &= ~XMAC_XIF_SEL_POR_CLK_SRC;