u-boot的快捷菜单详解（for mini2440）

- 日理万妓 2021-07-26 20:15 269阅读 0赞

## 本章来分析u-boot的快捷菜单 ##

**FriendlyARMMenu在main.c函数的main\_loop ()中被调用：**

{ 
    	void FriendlyARMMenu(void);
    	FriendlyARMMenu();
    }

**FriendlyARMMenu() 源码如下：**

void FriendlyARMMenu(void)
    { 
        char cmd_buf[300];
    	while(1) { 
    		int c;
    		printf("##### FriendlyARM U-Boot(" RELEASE_MARK ") for 2440 #####\n");
    		printf("[f] Format the nand flash\n");
    		printf("[v] Download u-boot.bin\n");
    		printf("[k] Download Linux kernel\n");
    		printf("[y] Download root yaffs2 image\n");
    		printf("[a] Download Absolute User Application\n");
    		printf("[s] Set the boot parameter of Linux\n");
    		printf("[b] Boot Linux\n");
    		printf("[r] Reboot\n");
    		//printf("[d] Download and Run\n");
    		printf("[q] Quit to shell\n");
    		printf("Enter your Selection:");
    
    		c = getc();
    		printf("%c\n", c >= ' ' && c <= 127 ? c : ' ');
    
    		switch(c) { 
    		case 'F': case 'f':
    			strcpy(cmd_buf, "nand erase");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'V': case 'v':
    			strcpy(cmd_buf, "usbslave 1 30000000; nand erase 0 40000; nand write.i 30000000 0 $(filesize_aligned);saveenv");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'K': case 'k':
    			strcpy(cmd_buf, "usbslave 1 30000000; nand erase 60000 500000; nand write.i 30000000 60000 $(filesize_aligned);saveenv");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'Y': case 'y':
    			strcpy(cmd_buf, "usbslave 1 30000000; nand erase 560000; nand write.yaffs 30000000 560000 $(filesize)");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'A': case 'a':
    			strcpy(cmd_buf, "usbslave 1 30000000; nand erase; nand write.i 30000000 0 $(filesize_aligned)");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'S': case 's':
    			strcpy(cmd_buf, "askenv bootargs \"linux cmd line:\" 200;saveenv");
    			run_command(cmd_buf, 0);
    			break;
    		case 'D': case 'd':
    			strcpy(cmd_buf, "usbslave 1 30000000; go 30000000");
    			run_command(cmd_buf, 0);
    			break;
    
    		case 'B': case 'b': case 'R': case 'r':
    			strcpy(cmd_buf, "reset");
    			run_command(cmd_buf, 0);
    			while(1);
    
    		case 'Q': case 'q':
    			return;
    
    		default:
    			;
    		}
    	}
    }

**1、分析 “\[v\] Download u-boot.bin\\n"这条命令的执行过程：**

strcpy(cmd_buf, "usbslave 1 30000000; nand erase 0 40000; nand write.i 30000000 0 $(filesize_aligned);saveenv");

**usbslave 1 30000000;**这条指令是把usb接收发送的数据下载到0x30000000。  
**nand erase 0 40000;**这条指令是擦除内核分区0~0x00040000地址的数据。  
**nand write.i 30000000 0** $ **(filesize\_aligned);** 这条指令是将0x30000000地址开始（ $ (filesize\_aligned) 大小的文件）烧写到nand flash内核分区中 0~$(filesize\_aligned)地址空间中去。  
**saveenv**这条指令是保存当前环境变量到nandflash。

**2、分析 “\[k\] Download Linux kernel\\n"这条命令的执行过程：**

strcpy(cmd_buf, "usbslave 1 30000000; nand erase 60000 500000; nand write.i 30000000 60000 $(filesize_aligned);saveenv");

**usbslave 1 30000000;**这条指令是把usb接收发送的数据下载到0x30000000。  
**nand erase 60000 500000;**这条指令是擦除内核分区60000~0x560000地址的数据（擦除60000 地址后面500000个地址数据）。  
**nand write.i 30000000 60000**  $ (filesize\_aligned); 这条指令是将0x30000000地址开始（ $ (filesize\_aligned) 大小的文件）烧写到nand flash内核分区中 60000 ~$(filesize\_aligned)地址空间中去。  
**saveenv**这条指令是保存当前环境变量到nandflash。

**3、run\_command(cmd\_buf, 0);**

通过run\_command（）函数运行strcpy拷贝到cmd\_buf中的指令。  
例如：`"usbslave 1 30000000; nand erase 60000 500000; nand write.i 30000000 60000 $(filesize_aligned);saveenv"`这条指令，由run\_command解析并且执行。