[Buildroot] New to embedded Linux... questions ref. buildroot

[Buildroot] New to embedded Linux... questions ref. buildroot

[Eric]

Good morning, all.

I have developed code for embedded Linux systems in the past, but 
this is my first time working on embedded Linux itself, installing it 
on boards, etc.

I have an Atmel NGW100 board that was given to me by a friend.  I 
have gotten to the point where I can download the operating system 
images from Atmel (ngw100_builds_1.0.2.tar.gz from the Atmel website; 
includes ngw_jffs2_root.img and ngw_jffs2_usr.img), install the root 
image on the board using tftp, and install the usr image on the board 
using wget.  All of that works... good thing because it seems that 
the OS on the board was corrupt or damaged, because I was getting all 
kinds of random errors on bootup.  Installing the new images fixed all of that.

Next step was to download buildroot and see if I can create images 
from that.  Downloaded buildroot-avr32-v2.2.0.tar.bz2 from the Atmel 
site and after several missteps was able to get it to build to completion.

During the later parts of the build process, I got the following messages:


Checking partition file: target/device/Atmel/atngw100/jffs2_partitions.txt
   * found root
     * which is root partition
   * found usr
Using mkfs.jffs2 at location './toolchain_build_avr32/mtd_orig/mkfs.jffs2'
Processing partition: root
   * options '-b -s 0x1000 -e 0x10000 -D
target/device/Atmel/atngw100/device_table.txt -p'
rootdir=/home/eric/AVR32Studio/buildroot/buildroot-avr32-v2.2.0/build_avr32/staging_dir/.tmp/root
table='target/device/Atmel/atngw100/device_table.txt'
mkfs.jffs2: skipping device_table entry '/boot': no parent directory!
mkfs.jffs2: skipping device_table entry '/dev': no parent directory!
mkfs.jffs2: skipping device_table entry '/tmp': no parent directory!
mkfs.jffs2: skipping device_table entry '/etc': no parent directory!
mkfs.jffs2: skipping device_table entry '/sys': no parent directory!
mkfs.jffs2: skipping device_table entry '/config': no parent directory!
mkfs.jffs2: skipping device_table entry '/proc': no parent directory!
mkfs.jffs2: skipping device_table entry '/lost+found': no parent directory!
mkfs.jffs2: skipping device_table entry '/media': no parent directory!
mkfs.jffs2: skipping device_table entry '/www': no parent directory!


Then at the end I got:


Build complete

Root file system files are in directory
'/home/eric/AVR32Studio/buildroot/buildroot-avr32-v2.2.0/binaries/atngw100'


(... indicating that it didn't seem all that upset over the missing 
parent directory indicated above).

Now 
/home/eric/AVR32Studio/buildroot/buildroot-avr32-v2.2.0/binaries/atngw100 
looks like this:


drwxrwxr-x 2 eric eric     4096 2008-10-23 03:42 .
drwxrwxr-x 3 eric eric     4096 2008-10-22 16:05 ..
-rw-rw-r-- 1 eric eric  1226398 2008-10-23 03:39 atngw100-linux-2.6.25.10-.gz
-rw-rw-r-- 1 eric eric        0 2008-10-23 03:40 rootfs.avr32.jffs2
-rw-r--r-- 1 eric eric  7798784 2008-10-23 03:42 rootfs.avr32.jffs2-root
-rw-r--r-- 1 eric eric  7451136 2008-10-23 03:42 rootfs.avr32.jffs2-usr
-rw-rw-r-- 1 eric eric 19230720 2008-10-23 03:42 rootfs.avr32.tar
-rw-rw-r-- 1 eric eric 10138625 2008-10-23 03:42 rootfs.avr32.tar.bz2
-rwxrwxr-x 1 eric eric   104708 2008-10-23 03:24 u-boot.bin


Now, my questions are...

1.  Do I need to be concerned about the "no parent directory" 
complaints above, and if so, what can I do about it?

2.  Are the rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr files 
the image files like the ngw_jffs2_root.img and ngw_jffs2_usr.img 
files I downloaded from Atmel, and are they installed in the same 
way?  I know... the obvious answer is "try it and see what 
happens".  I am fearful of blowing away my u-boot, because I am told 
I'd need a jtag pod to restore it, and I don't have a jtag pod and 
can't get one any time soon, so if I blow this one away I'm out of business.

3.  The file rootfs.avr32.tar.bz2, when uncompressed and untarred, 
looks like this:

drwxrwxr-x 21 eric eric     4096 2008-10-23 03:42 .
drwxrwxr-x  3 eric eric     4096 2008-10-23 07:22 ..
drwxrwxr-x  2 eric eric     4096 2008-10-23 03:42 bin
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:39 boot
drwxr-xr-x  2 eric eric     4096 2008-10-22 16:05 config
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 dev
drwxr-xr-x  8 eric eric     4096 2008-10-23 03:42 etc
drwxrwxr-x  4 eric eric     4096 2008-10-23 03:42 home
drwxr-xr-x  3 eric eric     4096 2008-10-23 03:42 lib
lrwxrwxrwx  1 eric eric       11 2008-10-23 07:22 linuxrc -> bin/busybox
drwx------  2 eric eric     4096 2008-10-23 03:42 lost+found
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 media
drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 mnt
drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 opt
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 proc
drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 root
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 sbin
drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 sys
drwxrwxr-x  2 eric eric     4096 2008-09-25 09:21 tmp
drwxrwxr-x  7 eric eric     4096 2008-10-23 03:22 usr
drwxrwxr-x 10 eric eric     4096 2008-09-25 09:21 var
drwxr-xr-x  7 eric eric     4096 2008-10-23 03:22 www

... which looks amazingly like the file structure that's on the 
NGW100 board.  Do I need to do anything with that tarball, or do I 
just load rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr and I'll 
have all I need?

4.  Speaking of u-boot, I see the buildroot process also created the 
file u-boot.bin.  Is this the file I need if I blow away my u-boot on 
the board, and is it true that the only way to install it is via a jtag pod?

Thanks to all for helping me get started on this...

[Buildroot] New to embedded Linux... questions ref. buildroot

[Bernhard Reutner-Fischer]

On Thu, Oct 23, 2008 at 07:47:54AM -0400, Eric wrote:

>Next step was to download buildroot and see if I can create images 
>from that.  Downloaded buildroot-avr32-v2.2.0.tar.bz2 from the Atmel 
>site and after several missteps was able to get it to build to completion.

Note that the above is not buildroot (as should be mentioned somewhere
where you downloaded it).
http://buildroot/uClibc.org/

[Buildroot] New to embedded Linux... questions ref. buildroot

[Peter Korsgaard]

>>>>> "Bernhard" == Bernhard Reutner-Fischer <rep.dot.nop@gmail.com> writes:

 Bernhard> On Thu, Oct 23, 2008 at 07:47:54AM -0400, Eric wrote:
 >> Next step was to download buildroot and see if I can create images 
 >> from that.  Downloaded buildroot-avr32-v2.2.0.tar.bz2 from the Atmel 
 >> site and after several missteps was able to get it to build to completion.

 Bernhard> Note that the above is not buildroot (as should be
 Bernhard> mentioned somewhere where you downloaded it).
 Bernhard> http://buildroot/uClibc.org/

That's http://buildroot.uclibc.org ;)

What Bernhard means is that you should ask Atmel for support on their
buildroot fork, we cannot help you.

-- 
Bye, Peter Korsgaard

[Buildroot] New to embedded Linux... questions ref. buildroot

[Eric]

At 09:38 AM 10/23/2008, Bernhard Reutner-Fischer wrote:

 >>>>>
>Note that the above is not buildroot (as should be mentioned somewhere
>where you downloaded it).
<<<<<

Uhhh ... ok ...

If "buildroot-avr32-v2.2.0.tar.bz2" is not buildroot (customized for 
AVR32), then what is it?  I saw nothing anywhere I visited when I 
downloaded it, that said it wasn't the "real" buildroot.

In fact, the download link to buildroot-avr32-v2.2.0.tar.bz2 on the 
Atmel website was broken, and when I emailed their webmaster to let 
him know about it, he emailed me the buildroot tarball.

When you say it's not buildroot, do you mean it's not the complete 
buildroot?  I know that one has to go through a "make source" step to 
download a bunch of sources, and I did that as part of the 
(hopefully) successful build.

 >>>>>
>http://buildroot/uClibc.org/
<<<<<

That's supposed to be buildroot DOT uClibc.org, right?  I tried that 
and just got the page that says that there is a mailing list and a 
buildroot web page.  Clicking on the Downloads link on that page and 
drilling down to the Daily Snapshots gives a bunch of files with 
names like buildroot-2008nnnn.tar.bz2... how are those different 
(except in version and perhaps a few platform-specific content 
differences) from buildroot-avr32-v2.2.0.tar.bz2?

[Buildroot] New to embedded Linux... questions ref. buildroot

[Peter Korsgaard]

>>>>> "Eric" == Eric  <spamsink@scoot.netis.com> writes:

 Eric> At 09:38 AM 10/23/2008, Bernhard Reutner-Fischer wrote:
 >>>>>> 
 >> Note that the above is not buildroot (as should be mentioned somewhere
 >> where you downloaded it).
 Eric> <<<<<

 Eric> Uhhh ... ok ...

 Eric> If "buildroot-avr32-v2.2.0.tar.bz2" is not buildroot
 Eric> (customized for AVR32), then what is it?  I saw nothing
 Eric> anywhere I visited when I downloaded it, that said it wasn't
 Eric> the "real" buildroot.

It is, the point is that we don't know what those customizations are.

 >> http://buildroot/uClibc.org/

 Eric> That's supposed to be buildroot DOT uClibc.org, right?  I tried
 Eric> that and just got the page that says that there is a mailing
 Eric> list and a buildroot web page.  Clicking on the Downloads link
 Eric> on that page and drilling down to the Daily Snapshots gives a
 Eric> bunch of files with names like
 Eric> buildroot-2008nnnn.tar.bz2... how are those different (except
 Eric> in version and perhaps a few platform-specific content
 Eric> differences) from buildroot-avr32-v2.2.0.tar.bz2?

We don't know. Ask Atmel what they have changed and why it doesn't
work for you.

-- 
Bye, Peter Korsgaard

[Buildroot] New to embedded Linux... questions ref. buildroot

[Robert Nelson]

Eric wrote:
> Good morning, all.
>
>
> Now, my questions are...
>
> 1.  Do I need to be concerned about the "no parent directory"
> complaints above, and if so, what can I do about it?
>    
It's fine, common error in buildroot, they'll be generated on first run 
with the kernel.

> 2.  Are the rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr files
> the image files like the ngw_jffs2_root.img and ngw_jffs2_usr.img
> files I downloaded from Atmel, and are they installed in the same
> way?  I know... the obvious answer is "try it and see what
> happens".  I am fearful of blowing away my u-boot, because I am told
> I'd need a jtag pod to restore it, and I don't have a jtag pod and
> can't get one any time soon, so if I blow this one away I'm out of business.
>    
The ngw has two options.

*-root can be flashed into the 8Mb of NOR flash
*-usr can be flashed into 8Mb of serial DataFlash

or

rootfs.avr32.tar can be written to an sd card

You'll have to configure u-boot for what ever method you use.

> 3.  The file rootfs.avr32.tar.bz2, when uncompressed and untarred,
> looks like this:
>
> drwxrwxr-x 21 eric eric     4096 2008-10-23 03:42 .
> drwxrwxr-x  3 eric eric     4096 2008-10-23 07:22 ..
> drwxrwxr-x  2 eric eric     4096 2008-10-23 03:42 bin
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:39 boot
> drwxr-xr-x  2 eric eric     4096 2008-10-22 16:05 config
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 dev
> drwxr-xr-x  8 eric eric     4096 2008-10-23 03:42 etc
> drwxrwxr-x  4 eric eric     4096 2008-10-23 03:42 home
> drwxr-xr-x  3 eric eric     4096 2008-10-23 03:42 lib
> lrwxrwxrwx  1 eric eric       11 2008-10-23 07:22 linuxrc ->  bin/busybox
> drwx------  2 eric eric     4096 2008-10-23 03:42 lost+found
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 media
> drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 mnt
> drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 opt
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 proc
> drwxrwxr-x  2 eric eric     4096 2008-10-22 16:05 root
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 sbin
> drwxr-xr-x  2 eric eric     4096 2008-10-23 03:42 sys
> drwxrwxr-x  2 eric eric     4096 2008-09-25 09:21 tmp
> drwxrwxr-x  7 eric eric     4096 2008-10-23 03:22 usr
> drwxrwxr-x 10 eric eric     4096 2008-09-25 09:21 var
> drwxr-xr-x  7 eric eric     4096 2008-10-23 03:22 www
>
> ... which looks amazingly like the file structure that's on the
> NGW100 board.  Do I need to do anything with that tarball, or do I
> just load rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr and I'll
> have all I need?
>
> 4.  Speaking of u-boot, I see the buildroot process also created the
> file u-boot.bin.  Is this the file I need if I blow away my u-boot on
> the board, and is it true that the only way to install it is via a jtag pod?
>
> Thanks to all for helping me get started on this...
Their are ways, but i've never done it without a jtagmk2

Take a look at these:

http://www.atmel.no/buildroot/ (ps v2.2.0 has been replaced by v.2.2.1, 
application notes, etc)
http://www.avrfreaks.net/wiki/index.php/Documentation:AVR32_General
http://www.avr32linux.org

PS. Since this is Atmel's fork, it would be best to ask your questions 
here: buildroot at avr32linux.org although Hans-Christian Egtvedt and 
Haavard Skinnemoen usually monitor this list. (even thou these stay in 
relative sync)

Regards,

Robert

[Buildroot] New to embedded Linux... questions ref. buildroot

[Eric]

At 10:48 AM 10/23/2008, Peter Korsgaard wrote:

 >>>>>
>We don't know. Ask Atmel what they have changed and why it doesn't
>work for you.
<<<<<

Good morning, Peter.

Actually, I don't know that it doesn't work.  Probably works fine 
once I clear up a few questions and get the nerve to try it.  :-)

All I really need (for now) is to find out if this means anything important...

Checking partition file: target/device/Atmel/atngw100/jffs2_partitions.txt
    * found root
      * which is root partition
    * found usr
Using mkfs.jffs2 at location './toolchain_build_avr32/mtd_orig/mkfs.jffs2'
Processing partition: root
    * options '-b -s 0x1000 -e 0x10000 -D
target/device/Atmel/atngw100/device_table.txt -p'
rootdir=/home/eric/AVR32Studio/buildroot/buildroot-avr32-v2.2.0/build_avr32/staging_dir/.tmp/root
table='target/device/Atmel/atngw100/device_table.txt'
mkfs.jffs2: skipping device_table entry '/boot': no parent directory!
mkfs.jffs2: skipping device_table entry '/dev': no parent directory!
mkfs.jffs2: skipping device_table entry '/tmp': no parent directory!
mkfs.jffs2: skipping device_table entry '/etc': no parent directory!
mkfs.jffs2: skipping device_table entry '/sys': no parent directory!
mkfs.jffs2: skipping device_table entry '/config': no parent directory!
mkfs.jffs2: skipping device_table entry '/proc': no parent directory!
mkfs.jffs2: skipping device_table entry '/lost+found': no parent directory!
mkfs.jffs2: skipping device_table entry '/media': no parent directory!
mkfs.jffs2: skipping device_table entry '/www': no parent directory!


... especially since it seems to report a successful build@the end.

Only other thing I need right now is to know from among the following files...

drwxrwxr-x 2 eric eric     4096 2008-10-23 03:42 .
drwxrwxr-x 3 eric eric     4096 2008-10-22 16:05 ..
-rw-rw-r-- 1 eric eric  1226398 2008-10-23 03:39 atngw100-linux-2.6.25.10-.gz
-rw-rw-r-- 1 eric eric        0 2008-10-23 03:40 rootfs.avr32.jffs2
-rw-r--r-- 1 eric eric  7798784 2008-10-23 03:42 rootfs.avr32.jffs2-root
-rw-r--r-- 1 eric eric  7451136 2008-10-23 03:42 rootfs.avr32.jffs2-usr
-rw-rw-r-- 1 eric eric 19230720 2008-10-23 03:42 rootfs.avr32.tar
-rw-rw-r-- 1 eric eric 10138625 2008-10-23 03:42 rootfs.avr32.tar.bz2
-rwxrwxr-x 1 eric eric   104708 2008-10-23 03:24 u-boot.bin


... whether rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr are 
the image files I want.  I know I can just try them and see if they 
work but as I said I'm nervous about blowing away the u-boot with no 
way to restore it.

[Buildroot] New to embedded Linux... questions ref. buildroot

[Bernhard Reutner-Fischer]

On Thu, Oct 23, 2008 at 10:43:13AM -0400, Eric wrote:
>At 09:38 AM 10/23/2008, Bernhard Reutner-Fischer wrote:
>
> >>>>>
>>http://buildroot/uClibc.org/
><<<<<
>
>That's supposed to be buildroot DOT uClibc.org, right?  I tried that 

yes, sorry.

[Buildroot] New to embedded Linux... questions ref. buildroot

[Peter Korsgaard]

>>>>> "Eric" == Eric  <spamsink@scoot.netis.com> writes:

Hi,

 Eric> Good morning, Peter.

Evening here ;)

 Eric> Actually, I don't know that it doesn't work.  Probably works fine 
 Eric> once I clear up a few questions and get the nerve to try it.  :-)

 Eric> All I really need (for now) is to find out if this means anything important...

 Eric> ... whether rootfs.avr32.jffs2-root and rootfs.avr32.jffs2-usr are 
 Eric> the image files I want.  I know I can just try them and see if they 
 Eric> work but as I said I'm nervous about blowing away the u-boot with no 
 Eric> way to restore it.

Again, please ask the Atmel people about those things, not us.

-- 
Bye, Peter Korsgaard