1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2012 The ChromiumOS Authors. All rights reserved.
*
* 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; version 2 of the License.
*
* 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.
*/
#include <arch/io.h>
#include <device/pnp.h>
#include <stdint.h>
#include <stdlib.h>
#include "lpc47n207.h"
/*
* This code tries to discover the SMSC LPC47N207 superio chip which can be
* connected over an LPC dongle. The chip could be bootstrap mapped to one of
* four LPC addresses: 0x2e, 0x4e, 0x162e, and 0x164e.
*
* Initializing the UART requires accesses to a few control registers. This
* structure includes the register offset and the value to write (along with
* the mask).
*/
typedef struct {
u8 conf_reg;
u8 value;
u8 mask;
} uart_conf;
/* All regs/values to write to initialize the LPC47N207 UART */
static const uart_conf uart_conf_data [] = {
{2, (1 << 3), (1 << 3)}, /* cr02, enable Primary UART power */
{0xc, (1 << 6), (1 << 6)}, /* cr0c, enable Primary UART high speed */
{0x24, (CONFIG_TTYS0_BASE >> 3) << 1, 0xff}, /* cr24, base addr */
};
void try_enabling_LPC47N207_uart(void)
{
u8 reg_value;
const uart_conf* conf_item;
u16 lpc_ports[] = {0x2e, 0x4e, 0x162e, 0x164e};
u16 lpc_port;
int i, j;
#define CONFIG_ENABLE 0x55
#define CONFIG_DISABLE 0xaa
for (j = 0; j < ARRAY_SIZE(lpc_ports); j++) {
lpc_port = lpc_ports[j];
/* enable CONFIG mode */
outb(CONFIG_ENABLE, lpc_port);
reg_value = inb(lpc_port);
if (reg_value != CONFIG_ENABLE) {
continue; /* There is no LPC device at this address */
}
do {
/*
* Registers 12 and 13 hold config address, look for a
* match.
*/
outb(0x12, lpc_port);
reg_value = inb(lpc_port + 1);
if (reg_value != (lpc_port & 0xff))
break;
outb(0x13, lpc_port);
reg_value = inb(lpc_port + 1);
if (reg_value != (lpc_port >> 8))
break;
/* This must be the SMSC LPC 47N207, enable the UART. */
for (i = 0; i < ARRAY_SIZE(uart_conf_data); i++) {
u8 reg, value, mask;
conf_item = uart_conf_data + i;
reg = conf_item->conf_reg;
value = conf_item->value;
mask = conf_item->mask;
outb(reg, lpc_port);
reg_value = inb(lpc_port + 1);
reg_value &= ~mask;
reg_value |= (value & mask);
outb(reg_value, lpc_port + 1);
}
} while (0);
outb(CONFIG_DISABLE, lpc_port);
}
}
|