blob: 2980ae6200f25949c75a32e834b0329ae3020471 (
plain)
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
|
/*
* Early debug UART support
*
* (C) Copyright 2014 Google, Inc
* Writte by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _DEBUG_UART_H
#define _DEBUG_UART_H
/*
* The debug UART is intended for use very early in U-Boot to debug problems
* when an ICE or other debug mechanism is not available.
*
* To use it you should:
* - Make sure your UART supports this interface
* - Enable CONFIG_DEBUG_UART
* - Enable the CONFIG for your UART to tell it to provide this interface
* (e.g. CONFIG_DEBUG_UART_NS16550)
* - Define the required settings as needed (see below)
* - Call debug_uart_init() before use
* - Call printch() to output a character
*
* Depending on your platform it may be possible to use this UART before a
* stack is available.
*
* If your UART does not support this interface you can probably add support
* quite easily. Remember that you cannot use driver model and it is preferred
* to use no stack.
*
* You must not use this UART once driver model is working and the serial
* drivers are up and running (done in serial_init()). Otherwise the drivers
* may conflict and you will get strange output.
*
*
* To enable the debug UART in your serial driver:
*
* - #include <debug_uart.h>
* - Define _debug_uart_init(), trying to avoid using the stack
* - Define _debug_uart_putc() as static inline (avoiding stack usage)
* - Immediately afterwards, add DEBUG_UART_FUNCS to define the rest of the
* functionality (printch(), etc.)
*
* If your board needs additional init for the UART to work, enable
* CONFIG_DEBUG_UART_BOARD_INIT and write a function called
* board_debug_uart_init() to perform that init. When debug_uart_init() is
* called, the init will happen automatically.
*/
/**
* debug_uart_init() - Set up the debug UART ready for use
*
* This sets up the UART with the correct baud rate, etc.
*
* Available CONFIG is:
*
* - CONFIG_DEBUG_UART_BASE: Base address of UART
* - CONFIG_BAUDRATE: Requested baud rate
* - CONFIG_DEBUG_UART_CLOCK: Input clock for UART
*/
void debug_uart_init(void);
#ifdef CONFIG_DEBUG_UART_BOARD_INIT
void board_debug_uart_init(void);
#else
static inline void board_debug_uart_init(void)
{
}
#endif
/**
* printch() - Output a character to the debug UART
*
* @ch: Character to output
*/
void printch(int ch);
/**
* printascii() - Output an ASCII string to the debug UART
*
* @str: String to output
*/
void printascii(const char *str);
/**
* printhex2() - Output a 2-digit hex value
*
* @value: Value to output
*/
void printhex2(uint value);
/**
* printhex4() - Output a 4-digit hex value
*
* @value: Value to output
*/
void printhex4(uint value);
/**
* printhex8() - Output a 8-digit hex value
*
* @value: Value to output
*/
void printhex8(uint value);
#ifdef CONFIG_DEBUG_UART_ANNOUNCE
#define _DEBUG_UART_ANNOUNCE printascii("<debug_uart> ");
#else
#define _DEBUG_UART_ANNOUNCE
#endif
/*
* Now define some functions - this should be inserted into the serial driver
*/
#define DEBUG_UART_FUNCS \
\
static inline void _printch(int ch) \
{ \
if (ch == '\n') \
_debug_uart_putc('\r'); \
_debug_uart_putc(ch); \
} \
\
void printch(int ch) \
{ \
_printch(ch); \
} \
\
void printascii(const char *str) \
{ \
while (*str) \
_printch(*str++); \
} \
\
static inline void printhex1(uint digit) \
{ \
digit &= 0xf; \
_debug_uart_putc(digit > 9 ? digit - 10 + 'a' : digit + '0'); \
} \
\
static inline void printhex(uint value, int digits) \
{ \
while (digits-- > 0) \
printhex1(value >> (4 * digits)); \
} \
\
void printhex2(uint value) \
{ \
printhex(value, 2); \
} \
\
void printhex4(uint value) \
{ \
printhex(value, 4); \
} \
\
void printhex8(uint value) \
{ \
printhex(value, 8); \
} \
\
void debug_uart_init(void) \
{ \
board_debug_uart_init(); \
_debug_uart_init(); \
_DEBUG_UART_ANNOUNCE \
} \
#endif
|
