linux内核移植笔记.doc

linux内核移植笔记目标机：ok6410交叉编译器：arm-linux-gcc-4.3.2交叉编译器路径：/usr/local/arm/4.3.2要移植的内核版本：linux-2.6.36U-BOOT：u-boot1.1.6文件系统类型： cramfs （目前使用光盘中linux-2.6.36的文件系统）一、 获取Linux内核源码首先，从官网上下载linux-2.6.36的内核。在/pub/linux/kernel/v2.6/ 找到。新建目录 mkdir /home/yueye/ok6410,接着将源码包放在该目录下。解压源码包到我的工作目录tar -zxvf linux-2.6.36.tar.gz C /home/yueye/ok6410二、 修改Makefile前提是你的PATH环境编译可以找到你的交叉编译工具链。查看PATH环境变量: echo $PATH添加环境变量：vi /.bashrc在打开的文件最后加上：export PATH=/usr/local/arm/4.3.2/bin:$PATHrootwww ok6410# cd linux-2.6.36rootwww linux-2.6.36# vi Makefile-#ARCH ?= $(SUBARCH)#CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:%=%)ARCH ?= armCROSS_COMPILE ?= /usr/local/arm/4.3.2/bin/arm-none-linux-gnueabi-备注：后来编译内核时出现无法找到交叉编译器的错误，这个问题郁闷了一天，原来在配置内核时要选择这个选项才能吃到我们设定的交叉编译器。在配置内核注意要选上以下选项Kernel Features - * Use the ARM EABI to compile the kernel * Allow old ABI binaries to run with this kernel (EXPERIMENTAL)三、 配置Nand Flash分区信息在linux-2.6.36archarmmach-s3c64xxmach-smdk6410.c文件中，添加如下内容：/tzq20120401 add it#include #include #include /*我的开发板Nand Flash大小为1GB，按如下大小进行分区*/3.1 建立分区表/* * tzq20120401 add it * Configuring Nandflash on SMDK6410 */struct mtd_partition ok6410_nand_part = /*1MB*/.name= Bootloader,.offset= 0,.size= (1 * SZ_1M),.mask_flags= MTD_CAP_NANDFLASH,/*5MB*/.name= Kernel,.offset= (1 * SZ_1M),.size= (5*SZ_1M) ,.mask_flags= MTD_CAP_NANDFLASH,/*120MB*/.name= User,.offset= (6 * SZ_1M),.size= (120*SZ_1M) ,/*THE LESS SIZE ALL*/.name= File System,.offset= MTDPART_OFS_APPEND,.size= MTDPART_SIZ_FULL,;注释：name:代表分区名字size:代表flash分区大小(单位：字节)offset:代表flash分区的起始地址(相对于0x0的偏移)目标板计划分4个区，分别存放bootloader,kernel,File System以及以便以后扩展使用的用户文件系统空间。各分区在Nandflash中起始地址.分区大小.记录如下：bootloader: start:0x00000000 len:0x00100000 1MB kernel: start:0x00100000 len:0x00500000 3MB rootfs: start:0x00600000 len:0x07800000 40MB User: start:0x08400000 len:0x40000000 20MB3.2 加入Nand Flash 分区static struct s3c2410_nand_set ok6410_nand_sets = 0 = .name = nand,.nr_chips = 1,.nr_partitions = ARRAY_SIZE(ok6410_nand_part),.partitions = ok6410_nand_part,;注释：nr_partitions:指明partition_info中定义的分区数目partitions:分区信息表3.3 建立Nand Flash芯片支持static struct s3c2410_platform_nand ok6410_nand_info = .tacls = 25,.twrph0 = 55,.twrph1 = 40,.nr_sets = ARRAY_SIZE(ok6410_nand_sets),.sets = ok6410_nand_sets,;注释：tacls,twrph0,twrph1的意思见S3C6410手册,这3个值最后会被设置到NFCONF中,见S3C6410手册.sets:支持的分区集nr_set:分区集的个数四、 指定启动时初始化static struct platform_device *smdk6410_devices _initdata = #ifdef CONFIG_SMDK6410_SD_CH0&s3c_device_hsmmc0,#endif#ifdef CONFIG_SMDK6410_SD_CH1&s3c_device_hsmmc1,#endif&s3c_device_i2c0,&s3c_device_i2c1,&s3c_device_fb,&s3c_device_ohci,&s3c_device_usb_hsotg,&s3c64xx_device_iisv4,&samsung_device_keypad,/tzq20120401 add it&s3c_device_nand,#ifdef CONFIG_REGULATOR&smdk6410_b_pwr_5v,#endif&smdk6410_lcd_powerdev,&smdk6410_smsc911x,&s3c_device_adc,&s3c_device_cfcon,&s3c_device_rtc,&s3c_device_ts,&s3c_device_wdt,;五、 加入Nand Flash芯片支持到Nand Flash驱动static void _init smdk6410_machine_init(void)u32 cs1;s3c_i2c0_set_platdata(NULL);s3c_i2c1_set_platdata(NULL);s3c_fb_set_platdata(&smdk6410_lcd_pdata);/tzq20120401 add its3c_nand_set_platdata(&ok6410_nand_info);samsung_keypad_set_platdata(&smdk6410_keypad_data);s3c24xx_ts_set_platdata(&s3c_ts_platform);/* configure nCS1 width to 16 bits */cs1 = _raw_readl(S3C64XX_SROM_BW) & (S3C64XX_SROM_BW_CS_MASK S3C64XX_SROM_BW_NCS1_SHIFT);cs1 |= (1 S3C64XX_SROM_BW_DATAWIDTH_SHIFT) |(1 S3C64XX_SROM_BW_WAITENABLE_SHIFT) |(1 S3C64XX_SROM_BW_BYTEENABLE_SHIFT) S3C64XX_SROM_BW_NCS1_SHIFT;_raw_writel(cs1, S3C64XX_SROM_BW);/* set timing for nCS1 suitable for ethernet chip */_raw_writel(0 S3C64XX_SROM_BCX_PMC_SHIFT) | (6 S3C64XX_SROM_BCX_TACP_SHIFT) | (4 S3C64XX_SROM_BCX_TCAH_SHIFT) | (1 S3C64XX_SROM_BCX_TCOH_SHIFT) | (0xe S3C64XX_SROM_BCX_TACC_SHIFT) | (4 S3C64XX_SROM_BCX_TCOS_SHIFT) | (0 Memory Technology Device (MTD) support - * MTD partitioning support #支持MTD分区这样我们在前面设置的分区才有意义 NAND Device Support - NAND Flash support for S3C/S3C SoC另外再把这个选项选上device drivers - Memory Technology Device (MTD) support - Caching block device access to MTD devices （此出勾选可防止出现：VFS: Cannot open root device mtdblock2 or unknown-block(2,0) 错误） 保存退出 七、 编译内核 make zImage 。编译成功后则在arch/arm/boot/目录下有zImage镜像八、 备注把得到的zImage镜像下载到开发板上出现如下问题VFS: Cannot open root device mtdblock2 or unknown-block(0,0)Please append a correct root= boot option; here are the available partitions:Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) (unwind_backtrace+0x0/0xec) from (panic+0x54/0x174) (panic+0x54/0x174) from (mount_block_root+0x25c/0x2ac) (mount_block_root+0x25c/0x2ac) from (prepare_namespace+0x164/0x1bc) (prepare_namespace+0x164/0x1bc) from (kernel_init+0x10c/0x14c) (kernel_init+0x10c/0x14c) from (kernel_thread_exit+0x0/0x8)问题原因：配置nandflash出错解决方法：解决方法就是修改arch./arm/plat-samsung/dev-nand.c 中的static struct resource s3c_nand_resource = 0 = .start = S3C_PA_NAND, .end = S3C_PA_NAND + SZ_1M -1, .flags = IORESOURCE_MEM, ;.end = S3C_PA_NAND + SZ_1M-1, 减去一就行了此外可能遇到如下问题问题二：.end_request: I/O error, dev mtdblock2, sector 16Buffer I/O error on device mtdblock2, logical block 2uncorrectable error : uncorrectable error : end_request: I/O error, dev mtdblock2, sector 24Buffer I/O error on device mtdblock2, logical block 3uncorrectable error : uncorrectable error : end_request: I/O error, dev mtdblock2, sector 24Buffer I/O error on device mtdblock2, logical block 3List of all partitions:1f00 256 mtdblock0 (driver?)1f01 3840 mtdblock1 (driver?)1f02 81920 mtdblock2 (driver?)1f03 176128 mtdblock3 (driver?)No filesystem could mount root, tried: cramfsKernel panic - not syncing: VFS: Unable to mount root fs on un