ml507 initrd problem

I have been trying to boot linux on an ml507 board for a few days now.
I am using xilinx's linux-2.6-xlnx.git kernel.  The rootfs is home
rolled.  I have had experience with NFS mounted root filesystems (not an
option here), cramfs, and romfs but have never tried running root out of
a ramdisk.  Because of that I am quite sure I have dorked this up.  Any
help will be appreciated!  I have added printk's in the kernel at
do_sys_open to get an idea what is going on.  Here is a snip of the boot
output:

 

.

Kernel command line: console=ttyS0,9600 ip=on init=/linuxrc
root=/dev/ram rw ram disk_size=9000

.

Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing
disabled 83e00000.serial: ttyS0 at MMIO 0x83e00003 (irq = 16) is a
16550A

.

eth0: XLlTemac: Send Threshold = 0, Receive Threshold = 0

eth0: XLlTemac: Send Wait bound = 0, Receive Wait bound = 0

IP-Config: Incomplete network configuration information.

open /dev/ram

fd 0

open /initrd.image

fd 1

RAMDISK: Compressed image found at block 0

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*RAMDISK: Compressed image found at block 0*
*VFS: Mounted root (ext2 filesystem).*
*Freeing unused kernel memory: 144k init*

That looks normal.

*open /dev/console*
*fd 0*
*code 10000000 - 1019854c, data 10195000 - 1019854c, stack bf85df00*
*open /dev/null*
*fd 3*
*open /etc/inittab*
*fd 3*

I don't know that stuff.

*And it gets very quiet at that point.  The kernel is still running in
ppc44x_idle.  Does this suggest anything to anyone?  I’ll be more than
happy to send or describe any config files to any one who might take pity.*

One question: What is in your /linuxrc? Do you have a shell in your initrd? What about booting into your shell with init=</path/to/shell>?


Regards,
Philipp


-- 
http://www.hachti.de

Hi Stu,

 

I realize you are trying to get your own ram disk to work, but if you
want to get a baseline you can use one we have on our wiki site, at
http://xilinx.wikidot.com/open-source-linux, under Files To Download.
This is the same ram disk that is included in the ELDK.

 

This is the ram disk that I use to test the ML507 design in our Git
tree.  I also use NFS a lot for testing.

 

Looks like you're close with yours, but I'm certainly no expert in that
area as I typically have something that works and don't change it.

 

Good luck,

John

 

________________________________

From: <redacted>
[mailto:linuxppc-embedded-bounces+john.linn=xilinx.com@ozlabs.org] On
Behalf Of Stu Bershtein
Sent: Tuesday, August 12, 2008 5:28 PM
To: <redacted>
Subject: ml507 initrd problem

 

I have been trying to boot linux on an ml507 board for a few days now.
I am using xilinx's linux-2.6-xlnx.git kernel.  The rootfs is home

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Morning John,

 

Thanks for the tip.  Running said ramdisk things certainly look lively,
I'll add a list of opens that I see at boot up at the bottom of this
email.  Looks like it's opening a shell and everything and yet I see no
serial communication from the shell, just quiet.  Am I correct to expect
the console to be the serial port (9pin DB) on the ml507 board at 9600
baud?  Also, if you could spare a desperate person a moment, could you
send me the boot command line that you use for testing with the ramdisk?
Finally, another member of this form suggested that there is a fully
build BSP (rootfs and all) available as 'linux_support.tar.gz' on the
Xilinx site.  Are you familiar with this?  I tried locating it a few
days ago to no avail.

 

Thanks very much for your help!

Stu

 

Freeing unused kernel memory: 144k init

open /dev/console

code 10000000 - 1009c134, data 1009a128 - 1009c134, stack bfdb9f00

open /lib/libcrypt.so.0

open /lib/libm.so.0

open /lib/libc.so.0

open /dev/console

open /dev/console

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Stu,

 

I'm assuming you're using arch/powerpc. The command line we use in the
device tree file, arch/powerpc/boot/dts/ml507.dts,  is bootargs =
"console=ttyS0 ip=on root=/dev/ram";

 

It sounds like you're getting console output til it switches from kernel
to user in the ram disk, but your message is a little confusing on that.
You should expect the shell output to be on the same serial port at the
same baud rate as the boot output of the kernel.

 

Yes the ML507 uses the 9 pin serial connector at 9600 baud.

 

We have removed the linux_support*.gz file when I put the bit streams
and ram disk on the wiki site.  If you have these files you have
everything.

 

You should be able to following the directions on the wiki site to get a
baseline working, although I didn't specifically say on the wiki to put
the ram disk image in the boot directory before you build or the make
command line.

 

The ram disk on our site should work correctly if you are using our
kernel with the default configuration, ml507_defconfig.  I always advice
people to get a good baseline with our stuff then make changes after you
see if baselined.

 

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