ENETDMAS_SRAM4_REG
enet_dmas_writel(priv, 0, ENETDMAS_SRAM4_REG, priv->rx_chan);
enet_dmas_writel(priv, 0, ENETDMAS_SRAM4_REG, priv->tx_chan);
enet_dmas_writel(priv, 0, ENETDMAS_SRAM4_REG, priv->rx_chan);
enet_dmas_writel(priv, 0, ENETDMAS_SRAM4_REG, priv->tx_chan);
usb_dmas_readl(udc, ENETDMAS_SRAM4_REG, ch_idx));