Root Filesystem Porting

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Root Filesystem Porting

• Lecture 8

2
? ?

• JFFS2 ??
• Mkfs.jffs2 ?? ? ??
• Root filesystem ??? ?? ? fusing

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jffs2 file system (1)

• JFFS2(Journaling Flash File System-2) file system
• NOR? flash memory? ???? ?? linux file system
• ?? flash memory? user file system?? ???? ?? ??
• Embedded system?? flash memory ??? ??? ??? ????
  ????, ??? ??? ??? ???? ???? ?? ???? ??
• Embedded system?? ???? ?? ?????? ?? ????? ????
  ??? ?? ??? ??
• ??? ??? ??? ??? ??
• cf) YAFFS

4
jffs2 file system (2)

• mkfs.jffs2 ??
• jffs2 file system? ??? ???? mkfs.jffs2 ????? ??
• Host? ?? ???? ???? ???? ??? ??
• cf) ????? mkfs.jffs2 ????? ?????? ????

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jffs2 file system (3)

• mkfs.jffs2 ?? (??)
• mtd-snapshot ??? download
• ftp//ftp.uk.linux.org/pub/people/dwmw2/mtd/cvs
• ????? /usr/local/pxa255? ?????.
• ?? ????? /usr/local/pxa255? ??
• ?? ??
• /usr/local/pxa255? ???? ??? ??.

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jffs2 file system (4)

• mkfs.jffs2 ?? (??)
• ??? - ??? ???? ?? util ????? ???? ??? ??.

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jffs2 file system (5)

• mkfs.jffs2 ?? (??)
• mkfs.jffs2 ???? ??

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jffs2 file system (6)

• mkfs.jffs2 ?? (??)
• ??? mkfs.jffs2?? ??? /sbin? ??.

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jffs2 file system (7)

• JFFS2 file system ??? ??
• Directory ??
• jffs2 file system?? ??? ????? ???.
• ????? /usr/local/pxa255/jffs2 ? ??.

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jffs2 file system (8)

• JFFS2 file system ??? ?? (??)
• ??? File ??
• jffs2 file system? ?? ?? ??? ?? ?? ????? ????.
• Flash memory?? 29 M? ????? ? ??? ??
• ????? test? ?? ????? welcome.txt ? ?????.

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jffs2 file system (9)

• JFFS2 file system ??? ?? (??)
• mkfs.jffs2
• mkfs.jffs2 ????? ???? jffs2 ????? jffs2 file
  system image? ??? ??.

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jffs2 file system (10)

• JFFS2 file system ??? ??
• ??? jffs2_image? /tftpboot ? ??
• cp /usr/local/pxa255/jffs2.img /tftpboot
• BLOB?? booting
• minicom? ?? ??.
• blob command mode? target system booting

13
Root filesystem ??? ?? (1)

• Root filesystem ??? ?? ??
• ?????? ??? rootfs ???? ??
• pwd
• /root/pxa255
• mkdir rootfs
• cd rootfs
• ?? ??? ???? ?? ??? ??????

14
Root filesystem ??? ?? (2)

• Root filesystem ??? ?? ?? (??)
• mkfs.jffs2 ????? /sbin?? ??
• chmod 755 mkfs.jffs2
• cp mkfs.jffs2 /sbin
• Root filesystem ??? ?? ???? ??
• cat mkfs-jffs2.sh

15
Root filesystem ??? ?? (3)

• Root filesystem ??? ?? ?? (??)
• Root filesystem ?? ????
• tar xvfz rootfs-2.6-pro3.tar.gz
• cd rootfs-2.6-pro3
• ls
• ? Root filesystem? ??? ??? ????? ????

16
Root filesystem ??? ?? (4)

• Root filesystem ??? ?? ?? (??)
• Root filesystem ??? ????
• cd .. pwd
• /root/pxa255-pro3/rootfs
• chmod 755 mkfs-jffs2.sh
• ./mkfs-jffs2.sh

17
Root filesystem ??? ?? (5)

• Root filesystem ??? ?? ?? (??)
• Root filesystem ??? ??
• u-boot bootloader? tftp flash fusing ??? ????
  ??? root filesystem ???? ????
• PRO3gt run rootf