change root filesystem

[llg]

Hi,

Changing root fs is easy as pie with tools and methods of of openezx.org.
I have created /dev/rfcomm[0-7] in the rootfs installed cyph's bluez to the phone's /etc then flashed back to phone.
I used Dan Kegel's cross-tool to compile gpsd. It works fine, gpspipe writes out data.

Is it possibile to merge somehow a custom root fs with original kernel(to be able to use phone to calls too)?
How the original kernel connects to the original root file system? What docs/faqs should I read to understand?
I have no glue what glibc is and how it affects a whole root fs and how it is tied to the kernel and what the problem with the one which is on the phone preinstalled... and what other considerations are there.

Thanks,

[Halftux]

Hi,
I used Dan Kegel's cross-tool to compile gpsd. It works fine, gpspipe writes out data.

Nice

Is it possibile to merge somehow a custom root fs with original kernel(to be able to use phone to calls too)?
How the original kernel connects to the original root file system? What docs/faqs should I read to understand?
I have no glue what glibc is and how it affects a whole root fs and how it is tied to the kernel and what the problem with the one which is on the phone preinstalled... and what other considerations are there.

Thanks,

The kernel sources are available so you can modify the ezx kernel. In the config file /arch/arm/defconfig you will find the mounting procedure for the root fs.

http://wiki.openezx.org/Kernel_hacking_-_linux-2.4

# To mount the normal enviroment from internal flash
#CONFIG_CMDLINE="root=3e00 rootfstype=cramfs ip=off console=ttyS2,115200n8 console=tty0"

# To mount rootfs from external flash, use the right rootfstype
CONFIG_CMDLINE="root=f301 rootfstype=ext3 ip=off console=ttyS2,115200n8 console=tty0"

The mtd map discribes the partitions. It is located in /drivers/mtd/maps.
Have a look here http://www.motorolafans.com/forums/d...html#post22774 Aleksei made a writeable rootfs.

[Halftux]

Mini Howto (maybe you need to change some folders in the patches):

tar xfvj a780-e680-linux.tar.bz2
source setenv-a780.sh
patch -p0 < mux_cli-for-2.4.20.patch
patch -p0 < fix-ezx-button-includes-for-2.4.20.diff
fix-make-dpm-compile.patch
fix-ptrace-include-for-2.4.20.diff
patch -p0 < ezx-mmc_driver.diff

copy .config to root of kernel
make ARCH=arm CROSS_COMPILE=arm-linux- oldconfig
make ARCH=arm CROSS_COMPILE=arm-linux- dep
make ARCH=arm CROSS_COMPILE=arm-linux- zImage
make ARCH=arm CROSS_COMPILE=arm-linux- modules

Make modules are only needed if you want to compile new modules.
The small-framebuffer-logo.patch removes the boot animation.
The usb-rootfs.patch can be useful when booting from external flash storage.

[llg]

Thanks a lot Halftux!

Some additions to your post:
- before make I had to edit scripts/Configure because make gave this error on ubuntu:
"scripts/Configure: line 546: .: .config: file not found"
line 546: ". $DEFAULT" --> "source ./$DEFAULT"

After boot with the compiled kernel /diska (/dev/tffsb1) was not mounted but who cares.

Do you know if there is an existing rootfs image which works relatively fast and fine with 2.4 kernel including phone calls with a native SDK?

Thanks

[Halftux]

Do you know if there is an existing rootfs image which works relatively fast and fine with 2.4 kernel including phone calls with a native SDK?

Thanks

There is no existing image. And so far there is only an existing compiler which runs on the phone. Look for zgcc. But the make is not working, so I would suggest to compile a new gcc maybe mkezx could help you. After compiling gcc you can add the headers from a sdk. Furthermore I dont know if this will fit on the limited fs root partition.

Why you do not choose a croostool + sdk on you computer. I think it is much easier and more comfortable.

[llg]

I will try cyph's opie, probably will satisfy my needs.

Can you suggest a documentation of croostool + sdk which works with old kernel on a780?

[Halftux]

Can you suggest a documentation of croostool + sdk which works with old kernel on a780?

I made here a post it is the best crosstool + sdk for A780.

http://www.motorolafans.com/forums/d...tml#post242855

Another very good crosstool is mkezx but without sdk.

[llg]

Wow, that topic is full of info I wanted I will read through later. Thank you!

2.4 kernel gives an error when mounting ext3, created by ubuntu: unsupported inode size: 256
Therefore I resized it with following command:
mkfs.ext3 -I 128 /dev/sdd1

When phone boots from flash-cramfs, which contains a script in /etc/rcS.d which mounts ext3 then the /dev/mmca1 is accessibile. With a kernel which tries to boot from f301 gives an error.
VFS: Cannot open root device "f301" or f3:01
Please append a correct root= boot option
Kernel panic: VFS: Unable to mount root fs on f3:01

How to resolve this?

Thanks,