src/superio/smsc/lpc47b272/lpc47b272_early_serial.c

   1 /*
   2  * lpc47b272_early_serial.c: Pre-RAM driver for SMSC LPC47B272 Super I/O chip
   3  *
   4  * Copyright (C) 2005 Digital Design Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #include <arch/romcc_io.h>
  22 #include "lpc47b272.h"
  23
  24 //----------------------------------------------------------------------------------
  25 // Function:            pnp_enter_conf_state
  26 // Parameters:          dev - high 8 bits = Super I/O port
  27 // Return Value:        None
  28 // Description:         Enable access to the LPC47B272's configuration registers.
  29 //
  30 static inline void pnp_enter_conf_state(device_t dev) {
  31         unsigned port = dev>>8;
  32     outb(0x55, port);
  33 }
  34
  35 //----------------------------------------------------------------------------------
  36 // Function:            pnp_exit_conf_state
  37 // Parameters:          dev - high 8 bits = Super I/O port
  38 // Return Value:        None
  39 // Description:         Disable access to the LPC47B272's configuration registers.
  40 //
  41 static void pnp_exit_conf_state(device_t dev) {
  42         unsigned port = dev>>8;
  43     outb(0xaa, port);
  44 }
  45
  46 //----------------------------------------------------------------------------------
  47 // Function:            lpc47b272_enable_serial
  48 // Parameters:          dev - high 8 bits = Super I/O port,
  49 //                                                low 8 bits = logical device number (per lpc47b272.h)
  50 //                                      iobase - processor I/O port address to assign to this serial device
  51 // Return Value:        bool
  52 // Description:         Configure the base I/O port of the specified serial device
  53 //                                      and enable the serial device.
  54 //
  55 static void lpc47b272_enable_serial(device_t dev, unsigned iobase)
  56 {
  57         pnp_enter_conf_state(dev);
  58         pnp_set_logical_device(dev);
  59         pnp_set_enable(dev, 0);
  60         pnp_set_iobase(dev, PNP_IDX_IO0, iobase);
  61         pnp_set_enable(dev, 1);
  62         pnp_exit_conf_state(dev);
  63 }