b391d74336
The serial output from the debug UART carries on going far to the right in the console. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Stefan Roese <sr@denx.de> Reviewed-by: Simon Glass <sjg@chromium.org>
166 lines
3.8 KiB
C
166 lines
3.8 KiB
C
/*
|
|
* 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 \
|
|
void printch(int ch) \
|
|
{ \
|
|
if (ch == '\n') \
|
|
_debug_uart_putc('\r'); \
|
|
_debug_uart_putc(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
|