src/superio/smsc/lpc47m10x/early_serial.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 #include <arch/io.h>
   4 #include <device/pnp_ops.h>
   5 #include <device/pnp.h>
   6 #include <stdint.h>
   7 #include "lpc47m10x.h"
   8
   9 void pnp_enter_conf_state(pnp_devfn_t dev)
  10 {
  11         u16 port = dev >> 8;
  12         outb(0x55, port);
  13 }
  14
  15 void pnp_exit_conf_state(pnp_devfn_t dev)
  16 {
  17         u16 port = dev >> 8;
  18         outb(0xaa, port);
  19 }
  20
  21 /**
  22  * Configure the base I/O port of the specified serial device and enable the
  23  * serial device.
  24  *
  25  * @param dev High 8 bits = Super I/O port, low 8 bits = logical device number.
  26  * @param iobase Processor I/O port address to assign to this serial device.
  27  */
  28 void lpc47m10x_enable_serial(pnp_devfn_t dev, u16 iobase)
  29 {
  30         pnp_enter_conf_state(dev);
  31         pnp_set_logical_device(dev);
  32         pnp_set_enable(dev, 0);
  33         pnp_set_iobase(dev, PNP_IDX_IO0, iobase);
  34         pnp_set_enable(dev, 1);
  35         pnp_exit_conf_state(dev);
  36 }