| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2014 Edward O'Callaghan <eocallaghan@alterapraxis.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| /* |
| * A generic romstage (pre-ram) driver for Fintek variant Super I/O chips. |
| * |
| * The following is derived directly from the vendor Fintek's data-sheets: |
| * |
| * To toggle between `configuration mode` and `normal operation mode` as to |
| * manipulation the various LDN's in Fintek Super I/O's we are required to pass |
| * magic numbers `passwords keys`. |
| * |
| * FINTEK_ENTRY_KEY := enable configuration : 0x87 |
| * FINTEK_EXIT_KEY := disable configuration : 0xAA |
| * |
| * To modify a LDN's configuration register, we use the index port to select |
| * the index of the LDN and then writing to the data port to alter the |
| * parameters. A default index, data port pair is 0x4E, 0x4F respectively, a |
| * user modified pair is 0x2E, 0x2F respectively. |
| * |
| */ |
| |
| #include <arch/io.h> |
| #include <device/pnp_ops.h> |
| #include <device/pnp.h> |
| #include <stdint.h> |
| #include "fintek.h" |
| |
| #define FINTEK_ENTRY_KEY 0x87 |
| #define FINTEK_EXIT_KEY 0xAA |
| |
| /* Enable configuration: pass entry key '0x87' into index port dev. */ |
| static void pnp_enter_conf_state(pnp_devfn_t dev) |
| { |
| u16 port = dev >> 8; |
| outb(FINTEK_ENTRY_KEY, port); |
| outb(FINTEK_ENTRY_KEY, port); |
| } |
| |
| /* Disable configuration: pass exit key '0xAA' into index port dev. */ |
| static void pnp_exit_conf_state(pnp_devfn_t dev) |
| { |
| u16 port = dev >> 8; |
| outb(FINTEK_EXIT_KEY, port); |
| } |
| |
| /* Bring up early serial debugging output before the RAM is initialized. */ |
| void fintek_enable_serial(pnp_devfn_t dev, u16 iobase) |
| { |
| pnp_enter_conf_state(dev); |
| pnp_set_logical_device(dev); |
| pnp_set_enable(dev, 0); |
| pnp_set_iobase(dev, PNP_IDX_IO0, iobase); |
| pnp_set_enable(dev, 1); |
| pnp_exit_conf_state(dev); |
| } |