REG_RXPKTBUF_CTRL
rtl_write_word(rtlpriv, REG_RXPKTBUF_CTRL, 0x0f01);
rtl_write_word(rtlpriv, REG_RXPKTBUF_CTRL, 0x0f01);
rtl_write_word(rtlpriv, REG_RXPKTBUF_CTRL, 0xf001);
tmp = rtl_read_byte(rtlpriv, REG_RXPKTBUF_CTRL);