Re: the procedure setting up jffs2

Wolfgang Denk
2002-09-12T23:14:32Z

Hi Karim,

in message <3D811741.FB5178A@opersys.com> you wrote:
>
> The chip you mention is bottom-boot, so the above will very likely wipe-out
> the bootloader. You probably want to partition your MTD device by modifying
> the mapping driver and then write the JFFS2 image to another partition then
> /dev/mtd0. Check drivers/mtd/tqm8xxl.c for an example.

We (more or less) consider this method of static partitioning
obsolete. We use (and recommend to our customers) a dynamic
partitioning, where "partition table" information is passed to the
Linux kernel by PPCBoot using the kernel command line.

For example, passing the kernel a boot argument of

mtdparts=0:256k(PPCboot)ro,768k(Kernel),-(Rest);1:-(myJFFS2)

results in this partitioning:

...
TQM flash bank 0: Using command line partition definition
Creating 3 MTD partitions on "TQM8xxL Bank 0":
0x00000000-0x00040000 : "PPCboot"
0x00040000-0x00100000 : "Kernel"
0x00100000-0x00400000 : "Rest"
TQM flash bank 1: Using command line partition definition
Creating 1 MTD partitions on "TQM8xxL Bank 1":
0x00000000-0x00400000 : "myJFFS2"
...

See the config option "CONFIG_MTD_CMDLINE_PARTS" in our kernel
sources.

Best regards,

Wolfgang Denk

--
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd@denx.de
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