我们转换文件系统到yaffs2或yaffs的时候，需要两个工具：mkyaffs2image和mkyaffsimage。
mkyaffs2image：制作yaffs2镜像
mkyaffsimage：制作yaffs镜像
关于yaffs2与yaffs的区别：
维基百科是这样说的：
YAFFS1和YAFFS2 主要差异还是在于PAGE 读写 size的大小，YAFFS2可支持到2K per page, 远高于YAFFS的512 Bytes, 因此对大容量NAND flash更具优势。其他与YAFFS1不同的是, YAFFS2不再写spare area, sequenceNumber 用29 bits 表示。Yaffs2还拥有YAFFS1所缺乏的SuperBlock, 因此YAFFS1严重依赖文件系统的read_super。
1. Download Yaffs using Git
We now operate a GIT server for our active projects. Here we give details of the setup:-
If you just want to browse or download code then it’s easiest to access the repositoryover the web. This is also the best
option if you are behind a firewall that does not allow direct GIT access(which is quite common).
To get a tarball of the top of the tree, just click ‘snapshot’ for the release that you want, or to quickly obtain a snapshot of the top of the tree you can use
this URL.
You will be offered a freshly-squeezed gzipped tarball of your choice.
If you want to use GIT directly from the command line then public read-only access is available, using the(bash) command:
git clone git://www.aleph1.co.uk/yaffs2
If you are a registered developer with a server account you can get read/write access using:
git clone ssh://www.aleph1.co.uk/home/aleph1/git/yaffs2
Please contact [email protected] ifyou are having problems using the GIT server.
If you need more info on how to use GIT then this website is a useful start. Many other tutorials are also available on the internet.
2. 解压缩
目前版本：yaffs2-HEAD-7e5cf0f.tar.gz
#tar zxvf yaffs2-HEAD-7e5cf0f.tar.gz
在解压缩后的目录里，有一个utils文件夹；这个就是我们需要的。
3. 配置Makefile
(1) Linux kernel
设置Linux kernel目录位置
## Change or override KERNELDIR to your kernel #KERNELDIR = /usr/src/kernel-headers-2.4.18
在下面设置：
KERNELDIR = /home/at91/linux-2.6.30
(2) CROSS_COMPILE
设置交叉编译器
## Change if you are using a cross-compiler MAKETOOLS =
在“MAKETOOLS=”后面，填写交叉编译器路径：/home/at91/x-tools/arm-softfp-linux-gnueabi/bin/arm-softfp-linux-gnueabi-
4. 头文件
(1) 新建mytypes.h
此头文件，主要解决u8，u16，s32等等的定义问题；
(2) 修改yutilsenv.h
此头文件主要为工具环境而设，所以把我们新建的mytypes.h加进来。
5. 生成
执行生成
make
附录：
1. Makefile
#Makefile for mkyaffs # # NB this is not yet suitable for putting into the kernel tree. # YAFFS: Yet another Flash File System. A NAND-flash specific file system. # # Copyright (C) 2002 Aleph One Ltd. # for Toby Churchill Ltd and Brightstar Engineering # # Created by Charles Manning <[email protected]> # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 as # published by the Free Software Foundation. ## Change or override KERNELDIR to your kernel #KERNELDIR = /usr/src/kernel-headers-2.4.18 KERNELDIR = /home/at91/linux-2.6.30 CFLAGS = -O2 -Wall -DCONFIG_YAFFS_UTIL CFLAGS+= -Wshadow -Wpointer-arith -Wwrite-strings -Wstrict-prototypes -Wmissing-declarations CFLAGS+= -Wmissing-prototypes -Wredundant-decls -Wnested-externs -Winline ## Change if you are using a cross-compiler MAKETOOLS = /home/at91/x-tools/arm-softfp-linux-gnueabi/bin/arm-softfp-linux-gnueabi- CC=$(MAKETOOLS)gcc COMMON_BASE_C_LINKS = yaffs_ecc.c COMMON_BASE_LINKS = $(COMMON_BASE_C_LINKS) yaffs_ecc.h yaffs_guts.h yaffs_packedtags2.h yaffs_trace.h COMMON_DIRECT_C_LINKS = yaffs_hweight.c COMMON_C_LINKS = $(COMMON_DIRECT_C_LINKS) $(COMMON_BASE_C_LINKS) COMMON_DIRECT_LINKS= $(COMMON_DIRECT_C_LINKS) yportenv.h yaffs_hweight.h yaffs_list.h COMMONOBJS = $(COMMON_C_LINKS:.c=.o) MKYAFFSSOURCES = mkyaffsimage.c MKYAFFSIMAGEOBJS = $(MKYAFFSSOURCES:.c=.o) MKYAFFS2SOURCES = mkyaffs2image.c MKYAFFS2LINKS = yaffs_packedtags2.c MKYAFFS2IMAGEOBJS = $(MKYAFFS2SOURCES:.c=.o) $(MKYAFFS2LINKS:.c=.o) BASE_LINKS = $(MKYAFFSLINKS) $(MKYAFFS2LINKS) $(COMMON_BASE_LINKS) DIRECT_LINKS = $(MKYAFFS_DIRECT_LINKS) $(MKYAFFS2_DIRECT_LINKS) $(COMMON_DIRECT_LINKS) ALL_LINKS = $(BASE_LINKS) $(DIRECT_LINKS) all: mkyaffsimage mkyaffs2image $(BASE_LINKS): ln -s ../[email protected] [email protected] $(DIRECT_LINKS): ln -s ../direct/[email protected] [email protected] $(COMMONOBJS) $(MKYAFFSIMAGEOBJS) $(MKYAFFS2IMAGEOBJS) : $(ALL_LINKS) $(COMMONOBJS) $(MKYAFFSIMAGEOBJS) $(MKYAFFS2IMAGEOBJS) : %.o: %.c $(CC) -c $(CFLAGS) $< -o [email protected] mkyaffsimage: $(MKYAFFSIMAGEOBJS) $(COMMONOBJS) $(CC) -o [email protected] $^ mkyaffs2image: $(MKYAFFS2IMAGEOBJS) $(COMMONOBJS) $(CC) -o [email protected] $^ clean: rm -f $(COMMONOBJS) $(MKYAFFSIMAGEOBJS) $(MKYAFFS2IMAGEOBJS) $(ALL_LINKS) mkyaffsimage mkyaffs2image core
2. mytypes.h
#ifndef __MYTYPES_H #define __MYTYPES_H typedef unsigned char u8; typedef unsigned short u16; typedef unsigned int u32; typedef unsigned long u64; typedef char s8; typedef short s16; typedef int s32; typedef long s64; #endif
3. yutilsenv.h
/*
* YAFFS: Yet another Flash File System . A NAND-flash specific file system.
*
* Copyright (C) 2002-2011 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1 as
* published by the Free Software Foundation.
*
* Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
*/
#ifndef __YAFFS_UTILSENV_H__
#define __YAFFS_UTILSENV_H__
#define YCHAR char
#define YUCHAR unsigned char
#include <sys/types.h>
#include <string.h>
#include "mytypes.h"
#include "yaffs_list.h"
#include "yaffs_hweight.h"
#define hweight8(x) yaffs_hweight8(x)
#define hweight32(x) yaffs_hweight32(x)
#define yaffs_trace(...) do {} while (0)
#endif