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
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* Joshua Henderson <joshua.henderson@microchip.com>
* Copyright (C) 2015 Microchip Technology Inc. All rights reserved.
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope 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 <asm/mach-pic32/pic32.h>
#include <asm/fw/fw.h>
#include "pic32mzda.h"
#include "early_pin.h"
/* Default early console parameters */
#define EARLY_CONSOLE_PORT 1
#define EARLY_CONSOLE_BAUDRATE 115200
#define UART_ENABLE BIT(15)
#define UART_ENABLE_RX BIT(12)
#define UART_ENABLE_TX BIT(10)
#define UART_TX_FULL BIT(9)
/* UART1(x == 0) - UART6(x == 5) */
#define UART_BASE(x) ((x) * 0x0200)
#define U_MODE(x) UART_BASE(x)
#define U_STA(x) (UART_BASE(x) + 0x10)
#define U_TXR(x) (UART_BASE(x) + 0x20)
#define U_BRG(x) (UART_BASE(x) + 0x40)
static void __iomem *uart_base;
static char console_port = -1;
static int __init configure_uart_pins(int port)
{
switch (port) {
case 1:
pic32_pps_input(IN_FUNC_U2RX, IN_RPB0);
pic32_pps_output(OUT_FUNC_U2TX, OUT_RPG9);
break;
case 5:
pic32_pps_input(IN_FUNC_U6RX, IN_RPD0);
pic32_pps_output(OUT_FUNC_U6TX, OUT_RPB8);
break;
default:
return -1;
}
return 0;
}
static void __init configure_uart(char port, int baud)
{
u32 pbclk;
pbclk = pic32_get_pbclk(2);
__raw_writel(0, uart_base + U_MODE(port));
__raw_writel(((pbclk / baud) / 16) - 1, uart_base + U_BRG(port));
__raw_writel(UART_ENABLE, uart_base + U_MODE(port));
__raw_writel(UART_ENABLE_TX | UART_ENABLE_RX,
uart_base + PIC32_SET(U_STA(port)));
}
static void __init setup_early_console(char port, int baud)
{
if (configure_uart_pins(port))
return;
console_port = port;
configure_uart(console_port, baud);
}
static char * __init pic32_getcmdline(void)
{
/*
* arch_mem_init() has not been called yet, so we don't have a real
* command line setup if using CONFIG_CMDLINE_BOOL.
*/
#ifdef CONFIG_CMDLINE_OVERRIDE
return CONFIG_CMDLINE;
#else
return fw_getcmdline();
#endif
}
static int __init get_port_from_cmdline(char *arch_cmdline)
{
char *s;
int port = -1;
if (!arch_cmdline || *arch_cmdline == '\0')
goto _out;
s = strstr(arch_cmdline, "earlyprintk=");
if (s) {
s = strstr(s, "ttyS");
if (s)
s += 4;
else
goto _out;
port = (*s) - '0';
}
_out:
return port;
}
static int __init get_baud_from_cmdline(char *arch_cmdline)
{
char *s;
int baud = -1;
if (!arch_cmdline || *arch_cmdline == '\0')
goto _out;
s = strstr(arch_cmdline, "earlyprintk=");
if (s) {
s = strstr(s, "ttyS");
if (s)
s += 6;
else
goto _out;
baud = 0;
while (*s >= '0' && *s <= '9')
baud = baud * 10 + *s++ - '0';
}
_out:
return baud;
}
void __init fw_init_early_console(char port)
{
char *arch_cmdline = pic32_getcmdline();
int baud = -1;
uart_base = ioremap_nocache(PIC32_BASE_UART, 0xc00);
baud = get_baud_from_cmdline(arch_cmdline);
if (port == -1)
port = get_port_from_cmdline(arch_cmdline);
if (port == -1)
port = EARLY_CONSOLE_PORT;
if (baud == -1)
baud = EARLY_CONSOLE_BAUDRATE;
setup_early_console(port, baud);
}
int prom_putchar(char c)
{
if (console_port >= 0) {
while (__raw_readl(
uart_base + U_STA(console_port)) & UART_TX_FULL)
;
__raw_writel(c, uart_base + U_TXR(console_port));
}
return 1;
}
|
