u-boot-2009.08在mini2440上的移植 增加yaffs2文件系统

转自：http://www.linuxidc.com/Linux/2011-05/35982p5.htm

移植环境

1，主机环境：VMare下CentOS 5.5 ，1G内存。

2，集成开发环境：Elipse IDE

3，编译编译环境：arm-linux-gcc v4.4.3，arm-none-eabi-gcc v4.5.1。

4，开发板：mini2440，2M nor flash，128M nand flash。

5，u-boot版本：u-boot-2009.08

5.1，添加Yaffs2镜像烧写功能

由于现在很多使用Nand Flash 的系统，在Linux 下都用Yaffs2作为存储数据的文件系统，甚至是根文件系统。所以在BootLoader 下能够烧写Yaffs2 映像文件变得很必要。对于Yaffs2 映像烧写的支持其实就是在烧写时，写入数据的同时，将镜像文件中的oob数据也写入到Nand Flash 的Spare 区。这和Yaffs 文件系统原理以及Nand Flash 的结构有关，注意：这里对Nand的操作是基于MTD架构方式。
通常一个Nnad Flash存储设备由若干块组成，1个块由若干页组成。一般128MB以下容量的Nand Flash芯片，一页大小为528B，被依次分为2个256B的主数据区和16B的额外空间；128MB以上容量的Nand Flash芯片，一页大小通常为2KB。由于Nand Flash出现位反转的概率较大，一般在读写时需要使用ECC进行错误检验和恢复。

Yaffs/yaffs2文件系统的设计充分考虑到Nand Flash以页为存取单位等的特点，将文件组织成固定大小的段(Chunk)。以528B的页为例，Yaffs/yaffs2文件系统使用前512B存储 数据和16B的额外空间存放数据的ECC和文件系统的组织信息等(称为OOB数据)。通过OOB数据，不但能实现错误检测和坏块处理，同时还可以避免加载 时对整个存储介质的扫描，加快了文件系统的加载速度。以下是Yaffs/yaffs2文件系统页的结构说明：

Yaffs页结构说明

==============================================

字节 用途

==============================================

0 - 511 存储数据(分为两个半部)

512 - 515 系统信息

516 数据状态字

517 块状态字

518 - 519 系统信息

520 - 522 后半部256字节的ECC

523 - 524 系统信息

525 - 527 前半部256字节的ECC

==============================================

好了，在了解Nand Flash组成和Yaffs/yaffs2文件系统结构后，我们再回到u-boot中。目前，在u-boot中已经有对Cramfs、Jffs2等文件系统的读写支持，但与带有数据校验等功能的OOB区的Yaffs/Yaffs2文件系统相比，他们是将所有文件数据简单的以线性表形式组织的。所以，我们只要在此基础上通过修改u-boot的Nand Flash读写命令，增加处理00B区域数据的功能，即可以实现对Yaffs/Yaffs2文件系统的读写支持。

实现u-boot对Yaffs或者Yaffs2文件系统的读写支持步骤如下：

【1】下面是需要修改的 4 个文件的补丁：

(1)打开/common/cmd_nand.c，定位到392行，在nand操作的do_nand函数中，修改如下：

if (read)

ret = nand_read_skip_bad(nand, off, &size,

(u_char *)addr);

else

ret = nand_write_skip_bad(nand, off, &size,

(u_char *)addr);

}

#if defined(CONFIG_MTD_NAND_YAFFS2)

else if (s != NULL && (!strcmp(s, ".yaffs2")))

{

nand->rw_oob = 1;

nand->skipfirstblk = 1;

ret = nand_write_skip_bad(nand,off,&size,(u_char *)addr);

nand->skipfirstblk = 0;

nand->rw_oob = 0;

}

#endif

else if (!strcmp(s, ".oob")) {

/* out-of-band data */

mtd_oob_ops_t ops = {

.oobbuf = (u8 *)addr,

.ooblen = size,

.mode = MTD_OOB_RAW

};

... ...

定位到509行附近，在Nand操作的命令集列表中添加Yaffs2对Nand的读写命令，修改如下

U_BOOT_CMD(nand, CONFIG_SYS_MAXARGS, 1, do_nand,

"NAND sub-system",

"info - show available NAND devices\n"

"nand device [dev] - show or set current device\n"

"nand read - addr off|partition size\n"

"nand write - addr off|partition size\n"

" read/write 'size' bytes starting at offset 'off'\n"

" to/from memory address 'addr', skipping bad blocks.\n"

"nand erase [clean] [off size] - erase 'size' bytes from\n"

" offset 'off' (entire device if not specified)\n"

#if defined(CONFIG_MTD_NAND_YAFFS2)

"nand write[.yaffs2] - addr off|partition size - write `size' byte yaffs image\n"

" starting at offset off' from memory address addr' (.yaffs2 for 512+16 NAND)\n"

#endif

"nand bad - show bad blocks\n"

"nand dump[.oob] off - dump page\n"

"nand scrub - really clean NAND erasing bad blocks (UNSAFE)\n"

"nand markbad off [...] - mark bad block(s) at offset (UNSAFE)\n"

"nand biterr off - make a bit error at offset (UNSAFE)"

#ifdef CONFIG_CMD_NAND_LOCK_UNLOCK

"\n"

"nand lock [tight] [status]\n"

" bring nand to lock state or display locked pages\n"

"nand unlock [offset] [size] - unlock section"

#endif

);

注意：这里只添加了yaffs2的写命令，u-boot下载用的是写功能。

(2)打开include/linux/mtd/mtd.h头文件，定位到131行，在mtd_info结构体中添加上面用到rw_oob和skipfirstblk数据成员，修改如下：

u_int32_t writesize;

#if defined(CONFIG_MTD_NAND_YAFFS2)

/*Thanks for hugerat's code*/

u_char rw_oob;

u_char skipfirstblk;

#endif

u_int32_t oobsize; /* Amount of OOB data per block (e.g. 16) */

u_int32_t oobavail; /* Available OOB bytes per block */

(3)在第一步关联的nand_write_skip_bad函数中添加对Nand OOB的相关操作，修改如下：

打开/drivers/mtd/nand/nand_util.c，定位到483行，在nand_write_skip_bad函数中添加代码，修改如下：

int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,

u_char *buffer)

{

int rval;

size_t left_to_write = *length;

size_t len_incl_bad;

u_char *p_buffer = buffer;

#if defined(CONFIG_MTD_NAND_YAFFS2)

if(nand->rw_oob==1)

{

size_t oobsize = nand->oobsize;

size_t datasize = nand->writesize;

int datapages = 0;

if (((*length)%(nand->oobsize+nand->writesize)) != 0)

{

printf ("Attempt to write error length data!\n");

return -EINVAL;

}

datapages = *length/(datasize+oobsize);

*length = datapages*datasize;

left_to_write = *length;

}

#endif

/* Reject writes, which are not page aligned */

if ((offset & (nand->writesize - 1)) != 0 ||

(*length & (nand->writesize - 1)) != 0) {

printf ("Attempt to write non page aligned data\n");

return -EINVAL;

}

len_incl_bad = get_len_incl_bad (nand, offset, *length);

if ((offset + len_incl_bad) >= nand->size) {

printf ("Attempt to write outside the flash area\n");

return -EINVAL;

}

#if !defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

if (len_incl_bad == *length) {

rval = nand_write (nand, offset, length, buffer);

if (rval != 0)

printf ("NAND write to offset %llx failed %d\n",

offset, rval);

return rval;

}

#endif

while (left_to_write > 0) {

size_t block_offset = offset & (nand->erasesize - 1);

size_t write_size;

WATCHDOG_RESET ();

if (nand_block_isbad (nand, offset & ~(nand->erasesize - 1))) {

printf ("Skip bad block 0x%08llx\n",

offset & ~(nand->erasesize - 1));

offset += nand->erasesize - block_offset;

continue;

}

#if defined(CONFIG_MTD_NAND_YAFFS2) //add yaffs2 file system support

if(nand->skipfirstblk==1)

{

nand->skipfirstblk=0;

printf ("Skip the first good block %llx\n", offset & ~(nand->erasesize - 1));

offset += nand->erasesize - block_offset;

continue;

}

#endif

if (left_to_write < (nand->erasesize - block_offset))

write_size = left_to_write;

else

write_size = nand->erasesize - block_offset;

printf("\rWriting at 0x%llx -- ",offset); //add yaffs2 file system support

rval = nand_write (nand, offset, &write_size, p_buffer);

if (rval != 0) {

printf ("NAND write to offset %llx failed %d\n",

offset, rval);

*length -= left_to_write;

return rval;

}

left_to_write -= write_size;

printf("%d%% is complete.",100-(left_to_write/(*length/100)));/*Thanks for hugerat's code*/

offset += write_size;

#if defined(CONFIG_MTD_NAND_YAFFS2)

/*Thanks for hugerat's code*/

if(nand->rw_oob==1) {

p_buffer += write_size+(write_size/nand->writesize*nand->oobsize);

} else {

p_buffer += write_size;

}

#else

p_buffer += write_size;

#endif

}

return 0;

}

(4)在第三步的nand_write_skip_bad函数中我们看到又对nand_write函数进行了访问，所以这一步是到nand_write函数中添加对yaffs2的支持。

打开/drivers/mtd/nand/nand_base.c，定位到1961行，修改如下：

static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,

size_t *retlen, const uint8_t *buf)

{

struct nand_chip *chip = mtd->priv;

int ret;

#if defined(CONFIG_MTD_NAND_YAFFS2)

/*Thanks for hugerat's code!*/

int oldopsmode = 0;

if(mtd->rw_oob==1)

{

int i = 0;

int datapages = 0;

size_t oobsize = mtd->oobsize;

size_t datasize = mtd->writesize;

uint8_t oobtemp[oobsize];

datapages = len / (datasize);

for(i = 0; i < (datapages); i++)

{

memcpy((void *)oobtemp, (void *)(buf + datasize * (i + 1)), oobsize);

memmove((void *)(buf + datasize * (i + 1)),

(void *)(buf + datasize * (i + 1) + oobsize),

(datapages - (i + 1)) * (datasize) + (datapages - 1) * oobsize);

memcpy((void *)(buf+(datapages) * (datasize + oobsize) - oobsize),

(void *)(oobtemp), oobsize);

}

}

#endif

/* Do not allow reads past end of device */

if ((to + len) > mtd->size)

return -EINVAL;

if (!len)

return 0;

nand_get_device(chip, mtd, FL_WRITING);

chip->ops.len = len;

chip->ops.datbuf = (uint8_t *)buf;

//chip->ops.oobbuf = NULL;

#if defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

/*Thanks for hugerat's code!*/

if(mtd->rw_oob!=1) {

chip->ops.oobbuf = NULL;

} else {

chip->ops.oobbuf = (uint8_t *)(buf+len);

chip->ops.ooblen = mtd->oobsize;

oldopsmode = chip->ops.mode;

chip->ops.mode = MTD_OOB_RAW;

}

#else

chip->ops.oobbuf = NULL;

#endif

ret = nand_do_write_ops(mtd, to, &chip->ops);

*retlen = chip->ops.retlen;

nand_release_device(mtd);

#if defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

/*Thanks for hugerat's code!*/

chip->ops.mode = oldopsmode;

#endif

return ret;

}

【2】在mini2440.h里添加yaffs2相关宏定义

打开include/configs/mini2440.h，定位到98行附近，加入下列代码：

/*

* Command line configuration.

*/

#include <config_cmd_default.h>

#define CONFIG_CMD_CACHE

#define CONFIG_CMD_DATE

#define CONFIG_CMD_ELF

#define CONFIG_CMD_NAND

#define CONFIG_CMD_JFFS2 /* JFFS2 Support*/

... ...

在文件末尾处加入下列代码：

/*-----------------------------------------------------------------------

* NAND flash settings

*/

#if defined(CONFIG_CMD_NAND)

#define CONFIG_NAND_S3C2410

#define CONFIG_SYS_NAND_BASE 0x4E000000

#define CONFIG_SYS_MAX_NAND_DEVICE 1 /* Max number of NAND devices */

#define SECTORSIZE 512

#define SECTORSIZE_2K 2048

#define NAND_SECTOR_SIZE SECTORSIZE

#define NAND_SECTOR_SIZE_2K SECTORSIZE_2K

#define NAND_BLOCK_MASK 511

#define NAND_BLOCK_MASK_2K 2047

#define NAND_MAX_CHIPS 1

#define CONFIG_MTD_NAND_VERIFY_WRITE

#define CONFIG_SYS_64BIT_VSPRINTF /* needed for nand_util.c */

#endif /* CONFIG_CMD_NAND */



#define CONFIG_JFFS2_NAND 1

//#undef CONFIG_JFFS2_CMDLINE

#define CONFIG_JFFS2_DEV "nand0"

#define CONFIG_JFFS2_PART_SIZE 0x480000

#define CONFIG_JFFS2_PART_OFFSET 0x80000

#define CONFIG_JFFS2_CMDLINE 1

#define MTDIDS_DEFAULT "nand0=nandflash0"

#define MTDPARTS_DEFAULT "mtdparts=nandflash0:384k(bootloader)," \

"128k(params)," \

"5m(kernel)," \

"-(root)"

#define CONFIG_MTD_NAND_YAFFS2 1

#define ENABLE_CMD_LOADB_X 1



5.2， 烧录yaffs2文件系统测试

重新编译后下载，nand方式启动，在u-boot的命令行输入nand help查看nand的命令，可以看到多了一个nand write[.yaffs2]的命令：

[u-boot@MINI2440]# nand help

nand - NAND sub-system

Usage:

nand info - show available NAND devices

nand device [dev] - show or set current device

nand read - addr off|partition size

nand write - addr off|partition size

read/write 'size' bytes starting at offset 'off'

to/from memory address 'addr', skipping bad blocks.

nand erase [clean] [off size] - erase 'size' bytes from

offset 'off' (entire device if not specified)

nand write[.yaffs2] - addr off|partition size - write `size' byte yaffs image

starting at offset off' from memory address addr' (.yaffs2 for 512+16 NAND)

nand bad - show bad blocks

nand dump[.oob] off - dump page

nand scrub - really clean NAND erasing bad blocks (UNSAFE)

nand markbad off [...] - mark bad block(s) at offset (UNSAFE)

nand biterr off - make a bit error at offset (UNSAFE)

[u-boot@MINI2440]#

这个就是用来下载yaffs2文件系统到nand中的命令了。首先需要将友善官方提供的有关mini2440的yaffs2文件系统文件root_qtopia-128M.img复制到linux宿主机的/tftpboot目录下，然后执行：

tf[u-boot@MINI2440]# tp 0x30000000 root_qtopia-128M.img

Filename 'root_qtopia-128M.img'.

Load address: 0x30000000

Loading: T ##########T T #####################################################T

##T T

#T T T T ######

Retry count exceeded; starting again

dm9000 i/o: 0x20000300, id: 0x90000a46

DM9000: running in 16 bit mode

MAC: 12:34:56:78:9a:bc

operating at 100M full duplex mode

Using dm9000 device

TFTP from server 10.1.0.128; our IP address is 10.1.0.129

Filename 'root_qtopia-128M.img'.

Load address: 0x30000000

Loading: T ###T ###T T ########

一直无休止循环，经网上搜索得知Uboot 端 tftp 程序传过来的Timeout参数不符合服务器端定义引起的，原文链接地址

Retry count exceeded; starting again 解决方法：tftp客户端传过来的timeout是7810，而服务器端定义的范围在1-255秒之间，不是服务器的问题，而是uboot中tftp参数设置的问题，参见TFTP Unsupported option(s) requested 问题详细分析及解决。

打开/net/net.c，定位到104行附近，修改如下：

#if defined(CONFIG_CMD_NET)

DECLARE_GLOBAL_DATA_PTR;

#ifndef CONFIG_ARP_TIMEOUT

# define ARP_TIMEOUT 10000UL*CONFIG_SYS_HZ/1000 //5000UL /* Milliseconds before trying ARP again */

#else

# define ARP_TIMEOUT CONFIG_ARP_TIMEOUT

#endif

定位到573行附近，修改如下：

#ifndef CONFIG_NET_MULTI

//NetSetTimeout (10000UL, startAgainTimeout);

NetSetTimeout (10000UL*CONFIG_SYS_HZ/1000, startAgainTimeout);

NetSetHandler (startAgainHandler);

#else /* !CONFIG_NET_MULTI*/

定位到585行附近，修改如下：

eth_init (gd->bd);

if (NetRestartWrap) {

NetRestartWrap = 0;

if (NetDevExists && !once) {

//NetSetTimeout (10000UL, startAgainTimeout);

NetSetTimeout (10000UL*CONFIG_SYS_HZ/1000, startAgainTimeout);

NetSetHandler (startAgainHandler);

} else {

NetState = NETLOOP_FAIL;

}

定位到779行附近，修改如下：

#define CDP_SYSOBJECT_TLV 0x0015

#define CDP_MANAGEMENT_ADDRESS_TLV 0x0016

#define CDP_TIMEOUT (250UL*CONFIG_SYS_HZ/1000) //250UL /* one packet every 250ms */

static int CDPSeq;

static int CDPOK;

打开/net/tftp.c，定位到16行，修改如下：

#define TIMEOUT 60000UL //5000UL /* Millisecs to timeout for lost pkt */

然后重新编译后下载测试：

[u-boot@MINI2440]# tftp 0x30000000 root_qtopia-128M.img

dm9000 i/o: 0x20000300, id: 0x90000a46

DM9000: running in 16 bit mode

MAC: 12:34:56:78:9a:bc

operating at 100M full duplex mode

Using dm9000 device

TFTP from server 10.1.0.128; our IP address is 10.1.0.129

Filename 'root_qtopia-128M.img'.

Load address: 0x30000000

Loading: T T T T T T T T T T

Retry count exceeded; starting again

dm9000 i/o: 0x20000300, id: 0x90000a46

DM9000: running in 16 bit mode

MAC: 12:34:56:78:9a:bc

operating at 100M full duplex mode

Using dm9000 device

TFTP from server 10.1.0.128; our IP address is 10.1.0.129

Filename 'root_qtopia-128M.img'.

Load address: 0x30000000

Loading: #################################################################

#################################################################

... ...

#################################################################

####################

done

Bytes transferred = 58487616 (37c7340 hex)

[u-boot@MINI2440]#

在yaffs2文件系统镜像下载到内存后:

[u-boot@MINI2440]# nand erase 0 0x40000

NAND erase: device 0 offset 0x0, size 0x40000

Erasing at 0x2000000000004 -- 0% complete.

OK

[u-boot@MINI2440]# nand write 0x30000000 0 0x40000

NAND write: device 0 offset 0x0, size 0x40000

Writing at 0x2000000020000 -- 100% is complete. 262144 bytes written: OK

[u-boot@MINI2440]#

可以看到，yaffs2文件系统烧录成功。下一步需要加载内核来挂载yaffs2文件系统。

接下来将进入u-boot的第六阶段，为u-boot-2009.08 增加引导内核功能。