[U-Boot] Searching for JFFS2 understanding.

[Charles Krinke]

I have a project with the Freescape MPC8323ERDB board and am having a little
trouble booting the jffs2 image and I suspect it is either a u-boot
environment string, a u-boot CONFIG* setting or a Linux CONFIG* setting.

At this point, I can build a rootfs.jffs2, include uImage into the
rootfs.jffs2 and from the u-boot prompt do things like this and even boot
from the uImage in the JFFS2 flash.

=> *fsload 0x00800000 /uImage*         //the uImage in the jffs2 rootfs.
=> *bootm 0x00800000 - 0xfe080000*


So, I think my confusion is in making the jump between u-boot's perception
of partitions in NOR flash and the kernels perception of partitions in NOR
flash.

I have *CONFIG_CMD_JFFS2* defined, but not *CONFIG_CMD_MTDPARTS* as they
seem to be mutually exclusive.

I have tried a bootargs of:

*root=/dev/mtdblock1 rw rootfstype=jffs2
mtdparts=nor0:3072k(u-boot),-(jffs2) console=ttyS0,115200*

thinking this would define sufficiently mtdparts for the Linux kernel to
boot. Maybe there is a C source file in the linux kernel that needs the mtd
partitioning information hard-code? I vaguely remember something like this a
while back.

At this point, I am hoping for a few ideas that will allow me to complete my
understanding of the boot process with JFFS2 so I can then get to the next
problem of understanding the boot process with UBI.

The end of the kernel boot shows this:
*MTDSB: dev_name "/dev/root"
MTDSB: lookup_bdev() returned 0
List of all partitions:
No filesystem could mount root, tried:  jffs2*

An "ls" in u-boot with DEBUG_JFFS2 defined gives me this:
*=> ls
---mtdparts_init---
dev id: type = 1, num = 0, size = 0x01000000, mtd_id = single part
part  : name = static, size = 0x01000000, offset = 0x00000000
--- jffs2_part_info: partition number 0 for device nor0 (single part)
Scanning JFFS2 FS: ...... done.
 drwxrwxr-x        0 Sat Apr 02 22:04:07 2011 bin
 drwxr-xr-x        0 Sat Apr 02 19:03:52 2011 dev
 drwxr-xr-x        0 Sat Apr 02 22:04:07 2011 etc
...
 -rw-r--r--  2003122 Sat Apr 02 22:03:34 2011 uImage
 drwxrwxr-x        0 Tue Nov 30 15:52:43 2010 usr
 drwxrwxr-x        0 Tue Nov 30 15:52:43 2010 var
=>
*

-- 
Charles Krinke