Linux·uboot编译问题

编译uboot时遇到问题：/home/book/test/u-boot-2012.04.01/include/asm/io.h:79: multiple definition of `__raw_writesb'

 

很明显是多个文件包含同一个头文件io.h导致的，在编译器连接时，会将工程中所有的符号整合在一起，由于文件中有重名变量，于是就出现了重复定义的错误。

查看io.h文件：vim /home/book/test/u-boot-2012.04.01/include/asm/io.h，发现存在编译条件设置

#ifndef __ASM_ARM_IO_H
#define __ASM_ARM_IO_H
......
#endif  /* __ASM_ARM_IO_H */

不是这个问题。那问题出在哪儿？

查看代码，发现在io.h文件中定义了几个变量（extern inline void __raw_writesb ...），而这个.h文件被多个文件包含，链接时就造成重复定义错误。

解决办法：

1、修改io.h文件：

注释掉下面几个变量定义

extern inline void __raw_writesb(unsigned int addr, const void *data, int bytelen)
{
        uint8_t *buf = (uint8_t *)data;
        while(bytelen--)
                __arch_putb(*buf++, addr);
}

extern inline void __raw_writesw(unsigned int addr, const void *data, int wordlen)
{
        uint16_t *buf = (uint16_t *)data;
        while(wordlen--)
                __arch_putw(*buf++, addr);
}

extern inline void __raw_writesl(unsigned int addr, const void *data, int longlen)
{
        uint32_t *buf = (uint32_t *)data;
        while(longlen--)
                __arch_putl(*buf++, addr);
}

extern inline void __raw_readsb(unsigned int addr, void *data, int bytelen)
{
        uint8_t *buf = (uint8_t *)data;
        while(bytelen--)
                *buf++ = __arch_getb(addr);
}

extern inline void __raw_readsw(unsigned int addr, void *data, int wordlen)
{
        uint16_t *buf = (uint16_t *)data;
        while(wordlen--)
                *buf++ = __arch_getw(addr);
}

extern inline void __raw_readsl(unsigned int addr, void *data, int longlen)
{
        uint32_t *buf = (uint32_t *)data;
        while(longlen--)
                *buf++ = __arch_getl(addr);
}

添加变量声明：

extern void __raw_writesb(unsigned int addr, const void *data, int bytelen);
extern void __raw_writesw(unsigned int addr, const void *data, int wordlen);
extern void __raw_writesl(unsigned int addr, const void *data, int longlen);
extern void __raw_readsb(unsigned int addr, void *data, int bytelen);
extern void __raw_readsw(unsigned int addr, void *data, int wordlen);
extern void __raw_readsl(unsigned int addr, void *data, int longlen);

2、在/home/book/test/u-boot-2012.04.01/arch/arm/cpu/arm920t/s3c24x0/目录下创建io.c文件，将注释掉的变量在io.c文件中定义

/* * (C) Copyright 2020  Wang Chuanbing */

#include
#include
#include

void __raw_writesb(unsigned int addr, const void *data, int bytelen)
{
        uint8_t *buf = (uint8_t *)data;
        while(bytelen--)
                __arch_putb(*buf++, addr);
}

void __raw_writesw(unsigned int addr, const void *data, int wordlen)
{
        uint16_t *buf = (uint16_t *)data;
        while(wordlen--)
                __arch_putw(*buf++, addr);
}

void __raw_writesl(unsigned int addr, const void *data, int longlen)
{
        uint32_t *buf = (uint32_t *)data;
        while(longlen--)
                __arch_putl(*buf++, addr);
}

void __raw_readsb(unsigned int addr, void *data, int bytelen)
{
        uint8_t *buf = (uint8_t *)data;
        while(bytelen--)
                *buf++ = __arch_getb(addr);
}

void __raw_readsw(unsigned int addr, void *data, int wordlen)
{
        uint16_t *buf = (uint16_t *)data;
        while(wordlen--)
                *buf++ = __arch_getw(addr);
}

void __raw_readsl(unsigned int addr, void *data, int longlen)
{
        uint32_t *buf = (uint32_t *)data;
        while(longlen--)
                *buf++ = __arch_getl(addr);
}

3、添加io.c文件到同一目录下的Makefile文件中

COBJS-$(CONFIG_USE_IRQ) += interrupts.o
COBJS-$(CONFIG_DISPLAY_CPUINFO) += cpu_info.o
COBJS-y += io.o
COBJS-y += speed.o
COBJS-y += timer.o
COBJS-y += usb.o
COBJS-y += usb_ohci.o

重新编译后问题解决