How to figure out correct mmc device ??

[nephilim1973]

Hi folks...

As described in
http://plugcomputer.org/plugforum/index.php?topic=711.msg4437#msg4437
my SheevaPlug doesn't recognize my mmc after updating to 2.6.30.6 kernel.

The standard bootcmd shows "mmc 0:1"

Marvell>> printenv bootcmd
bootcmd=setenv bootargs $(bootargs_console) $(bootargs_root); mmcinit; ext2load mmc 0:1 0x800000 /uImage; bootm 0x00800000

I think, 0:1 could be "disk 1, partition 2"
(like GRUB ??)

After changin the kernel-path only and hitting ENTER...

Marvell>> setenv bootcmd setenv bootargs $(bootargs_console) $(bootargs_root); mmcinit; ext2load mmc 0:1 0x800000 /sheeva-2.6.30.6-uImage; bootm 0x00800000

leaving mmc device with the same options, I get following error...

SDHC found. Card desciption is:
Manufacturer:       0x02, OEM "TM"
Product name:       "SD04G", revision 3.8
Serial number:      3056159759
Manufacturing date: 12/2008
CRC:                0x00, b0 = 0

** Unable to read "/sheeva-2.6.30.6-uImage" from mmc 0:1 **
## Booting image at 00800000 ...
Bad Magic Number
Marvell>>

How I could search for mmc device, like "fdisk"

mmcinit shows

SDHC found. Card desciption is:
Manufacturer:       0x02, OEM "TM"
Product name:       "SD04G", revision 3.8
Serial number:      3056159759
Manufacturing date: 12/2008
CRC:                0x00, b0 = 0

Best regards
Bjoern

[nephilim1973]

SOLVED:

- Put mmc into desktop computer
- Copy new 2.6.30.6 uImage to mmc-partition with ROOTFS

Ready...

[DamonHD]

When you say 'copy to' do you mean to /boot/uImage in that partition?

Rgds

Damon

[nephilim1973]

Hi DamonHD...

To be precisely:

copy /sheeva-2.6.30.6-uImage from partition "sheevaplug-rootf" on MMC
to
/uImage on partition "sheevaplug-uImag" on MMC

This solved all my problems so far.
No modifying for "bootcmd" was necessary...

Best regards and good luck!
Bjoern

[restamp]

I suspect the problem may be a glitchy bug in Uboot, which seems to have problems reading some files from the mmc, or perhaps off an ext2 fs.

1.  What does the Uboot "ext2ls mmc 0:1 /" command show?

2.  If the ext2ls command shows your uImage.whatever file to be zero length, try copying it to another name, like nephilim1973 suggests.  It seems the Uboot can read most files, but for some reason it cannot read all of them.  The files it cannot read seem random, but consistent.

3.  If an ext2ls of uImage.whatever shows the correct length, compare its sum to the original kernel image to verify it is indeed the correct file.

If you produce several identical copies, I think there is a high probability one will prove bootable.

[nephilim1973]

My MMC shows

"** Bad partition - mmc 0:1 **"

after an

"ext2ls mmc 0:1 /"