src/superio/nuvoton/nct5104d/early_init.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 #include <arch/io.h>
   4 #include <device/pnp.h>
   5 #include <stdint.h>
   6 #include "nct5104d.h"
   7
   8 #define NUVOTON_ENTRY_KEY 0x87
   9 #define NUVOTON_EXIT_KEY 0xAA
  10
  11 /* Enable configuration: pass entry key '0x87' into index port dev
  12  * two times. */
  13 static void pnp_enter_conf_state(pnp_devfn_t dev)
  14 {
  15         u16 port = dev >> 8;
  16         outb(NUVOTON_ENTRY_KEY, port);
  17         outb(NUVOTON_ENTRY_KEY, port);
  18 }
  19
  20 /* Disable configuration: pass exit key '0xAA' into index port dev. */
  21 static void pnp_exit_conf_state(pnp_devfn_t dev)
  22 {
  23         u16 port = dev >> 8;
  24         outb(NUVOTON_EXIT_KEY, port);
  25 }
  26
  27 /* Route UARTD to pins 41-48 */
  28 void nct5104d_enable_uartd(pnp_devfn_t dev)
  29 {
  30         u8 tmp;
  31         u16 port = dev >> 8;
  32         pnp_enter_conf_state(dev);
  33         outb(0x1c, port);
  34         tmp = inb(port + 1);
  35         tmp |= 0x04;
  36         outb(tmp, port + 1);
  37         pnp_exit_conf_state(dev);
  38 }