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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
|
/*
* (C) Copyright 2009 SAMSUNG Electronics
* Minkyu Kang <mk7.kang@samsung.com>
* Heungjun Kim <riverful.kim@samsung.com>
*
* based on drivers/serial/s3c64xx.c
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/uart.h>
#include <asm/arch/clk.h>
#include <serial.h>
static inline struct s5p_uart *s5p_get_base_uart(int dev_index)
{
u32 offset = dev_index * sizeof(struct s5p_uart);
return (struct s5p_uart *)(samsung_get_base_uart() + offset);
}
/*
* The coefficient, used to calculate the baudrate on S5P UARTs is
* calculated as
* C = UBRDIV * 16 + number_of_set_bits_in_UDIVSLOT
* however, section 31.6.11 of the datasheet doesn't recomment using 1 for 1,
* 3 for 2, ... (2^n - 1) for n, instead, they suggest using these constants:
*/
static const int udivslot[] = {
0,
0x0080,
0x0808,
0x0888,
0x2222,
0x4924,
0x4a52,
0x54aa,
0x5555,
0xd555,
0xd5d5,
0xddd5,
0xdddd,
0xdfdd,
0xdfdf,
0xffdf,
};
void serial_setbrg_dev(const int dev_index)
{
DECLARE_GLOBAL_DATA_PTR;
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
u32 uclk = get_uart_clk(dev_index);
u32 baudrate = gd->baudrate;
u32 val;
val = uclk / baudrate;
writel(val / 16 - 1, &uart->ubrdiv);
writew(udivslot[val % 16], &uart->udivslot);
}
/*
* Initialise the serial port with the given baudrate. The settings
* are always 8 data bits, no parity, 1 stop bit, no start bits.
*/
int serial_init_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* reset and enable FIFOs, set triggers to the maximum */
writel(0, &uart->ufcon);
writel(0, &uart->umcon);
/* 8N1 */
writel(0x3, &uart->ulcon);
/* No interrupts, no DMA, pure polling */
writel(0x245, &uart->ucon);
serial_setbrg_dev(dev_index);
return 0;
}
static int serial_err_check(const int dev_index, int op)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
unsigned int mask;
/*
* UERSTAT
* Break Detect [3]
* Frame Err [2] : receive operation
* Parity Err [1] : receive operation
* Overrun Err [0] : receive operation
*/
if (op)
mask = 0x8;
else
mask = 0xf;
return readl(&uart->uerstat) & mask;
}
/*
* Read a single byte from the serial port. Returns 1 on success, 0
* otherwise. When the function is succesfull, the character read is
* written into its argument c.
*/
int serial_getc_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* wait for character to arrive */
while (!(readl(&uart->utrstat) & 0x1)) {
if (serial_err_check(dev_index, 0))
return 0;
}
return (int)(readb(&uart->urxh) & 0xff);
}
/*
* Output a single byte to the serial port.
*/
void serial_putc_dev(const char c, const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
/* wait for room in the tx FIFO */
while (!(readl(&uart->utrstat) & 0x2)) {
if (serial_err_check(dev_index, 1))
return;
}
writeb(c, &uart->utxh);
/* If \n, also do \r */
if (c == '\n')
serial_putc('\r');
}
/*
* Test whether a character is in the RX buffer
*/
int serial_tstc_dev(const int dev_index)
{
struct s5p_uart *const uart = s5p_get_base_uart(dev_index);
return (int)(readl(&uart->utrstat) & 0x1);
}
void serial_puts_dev(const char *s, const int dev_index)
{
while (*s)
serial_putc_dev(*s++, dev_index);
}
/* Multi serial device functions */
#define DECLARE_S5P_SERIAL_FUNCTIONS(port) \
int s5p_serial##port##_init(void) { return serial_init_dev(port); } \
void s5p_serial##port##_setbrg(void) { serial_setbrg_dev(port); } \
int s5p_serial##port##_getc(void) { return serial_getc_dev(port); } \
int s5p_serial##port##_tstc(void) { return serial_tstc_dev(port); } \
void s5p_serial##port##_putc(const char c) { serial_putc_dev(c, port); } \
void s5p_serial##port##_puts(const char *s) { serial_puts_dev(s, port); }
#define INIT_S5P_SERIAL_STRUCTURE(port, name, bus) { \
name, \
bus, \
s5p_serial##port##_init, \
NULL, \
s5p_serial##port##_setbrg, \
s5p_serial##port##_getc, \
s5p_serial##port##_tstc, \
s5p_serial##port##_putc, \
s5p_serial##port##_puts, }
DECLARE_S5P_SERIAL_FUNCTIONS(0);
struct serial_device s5p_serial0_device =
INIT_S5P_SERIAL_STRUCTURE(0, "s5pser0", "S5PUART0");
DECLARE_S5P_SERIAL_FUNCTIONS(1);
struct serial_device s5p_serial1_device =
INIT_S5P_SERIAL_STRUCTURE(1, "s5pser1", "S5PUART1");
DECLARE_S5P_SERIAL_FUNCTIONS(2);
struct serial_device s5p_serial2_device =
INIT_S5P_SERIAL_STRUCTURE(2, "s5pser2", "S5PUART2");
DECLARE_S5P_SERIAL_FUNCTIONS(3);
struct serial_device s5p_serial3_device =
INIT_S5P_SERIAL_STRUCTURE(3, "s5pser3", "S5PUART3");
|
