[HOWTO] Build custom kernel, libraries and applications on your own - Gen8 Android Development

For building own custom stuff for my Gen8 Device I set up an Ubuntu 10.10 32bit Virtual Machine, so everything in here refers to it, may be different on other linux system.
[disclaimer]This is only a HowTo, if you brick your android device with some custom kernels or other stuff, don't blame me! I'm not responsible for anything you do![/disclaimer]
Notice: ** = you only have to do this step once
Prerequisites for Ubuntu 10.10 32 Bit: **
Code:
# sudo apt-get install git-core flex bison gperf libsdl-dev libesd0-dev libwxgtk2.6-dev build-essential zip curl automake autoconf libtool gettext texinfo libmpfr1ldbl
Prepare environment: **
Code:
# mkdir -pv $HOME/{archos,bin}
# echo export ARCHOS=\$HOME/archos >> ~/.bashrc
# echo export PATH=\$HOME/bin:\$PATH >> ~/.bashrc
# cd $HOME/archos
# wget -Oavos_env.tgz http://archos-gen8-dvb.googlecode.com/files/avos_env_20110415.tgz
# tar xzf avos_env.tgz
# install -m755 cross $HOME/bin/
# rm -f cross avos_env.tgz
RESTART CONSOLE OR REBOOT COMPUTER!
Toolchain: **
Code:
# cd $ARCHOS
# make all
Configure kernel:
Code:
# cd $ARCHOS
# make kernel-config
Restore kernel config:
Code:
# cd $ARCHOS
# make kernel-reset
Build kernel:
Code:
# cd $ARCHOS
# make kernel-build
CrossCompile: (this is just an example for if you want to build some linux libraries or tools)
Code:
# echo $ARCHOS
# cd ..xyz../..zyx../
# cross make

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I followed your instructions, and I got all the way to the end, but when I did 'make kernel-build' it ended with this:
drivers/built-in.o: In function `archos_dpm_suspend':
/home/zyntax/archos/gen8-gpl-froyo/linux/drivers/usb/storage/archos_hdd.c:261: undefined reference to `usbsata_power'
make[3]: *** [.tmp_vmlinux1] Error 1
make[2]: *** [sub-make] Error 2
make[2]: Leaving directory `/home/zyntax/archos/gen8-gpl-froyo/linux'
make[1]: *** [/home/zyntax/archos/gen8-gpl-froyo/buildroot//linux/arch/arm/boot/zImage] Error 2
make[1]: Leaving directory `/home/zyntax/archos/gen8-gpl-froyo/buildroot'
make: *** [kernel-build] Error 2
[email protected]:~/archos$
This is on a fresh install of Ubuntu 10.10 32-bit in Virtualbox. I installed it, updated the OS, then started your steps. Not sure if this is normal and I'm holding off on the last step. I did do one extra step: in 'make kernal-config' I deselected all the Archos boards under System Type except for the A101IT since that's what I have.

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jbradshw said:
This is on a fresh install of Ubuntu 10.10 32-bit in Virtualbox. I installed it, updated the OS, then started your steps. Not sure if this is normal and I'm holding off on the last step. I did do one extra step: in 'make kernal-config' I deselected all the Archos boards under System Type except for the A101IT since that's what I have.
Click to expand...
Click to collapse
can you please try again without modifying kernel config?

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Did that, now I get this:
CC [M] drivers/usb/musb/omap2430.o
/home/zyntax/archos/gen8-gpl-froyo/linux/drivers/usb/musb/omap2430.c:221: warning: 'omap_phy_read' defined but not used
LD [M] drivers/usb/musb/musb_hdrc.o
LD drivers/built-in.o
make[2]: *** [sub-make] Error 2
make[2]: Leaving directory `/home/zyntax/archos/gen8-gpl-froyo/linux'
make[1]: *** [/home/zyntax/archos/gen8-gpl-froyo/buildroot//linux/arch/arm/boot/zImage] Error 2
make[1]: Leaving directory `/home/zyntax/archos/gen8-gpl-froyo/buildroot'
make: *** [kernel-build] Error 2
I don't believe I changed anything besides what I mentioned earlier. Is there anyway to get back a default kernel-config?

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hehe, I thought you should try with default kernel-config
I added a section for restoring kernel config in the start posting :
chulri said:
[*]Restore kernel config:
Code:
# cd $ARCHOS
# tar xzf gen8-gpl-froyo.tgz gen8-gpl-froyo/linux/linux.config
Click to expand...
Click to collapse

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Well I did poke around in the config, but as far as I remember I only removed those extra archos systems. I'll restore the default and run it again later tonight.
Thanks.

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jbradshw said:
Well I did poke around in the config, but as far as I remember I only removed those extra archos systems. I'll restore the default and run it again later tonight.
Click to expand...
Click to collapse
You can't remove other devices (like A32, A101 etc) from Linux kernel config because Archos made bad dependencies for different parts of the kernel and even 70S requires some USB kernel code, it's only compiled when you choose A101 - so either you clean it up manually, or you are required to leave checked other archos devices :/

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Thanks for this howto, this is gonna be useful for me, should be a sticky.

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OK the make kernel-build worked without errors. Now I'm just questioning the command 'cd ..xyz../..zyx../' I don't have any files or directories called that, and running that reports the same. Can I just skip that and do the make cross?

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@jbradshw that's just a sample if someone wants to crosscompile something (e.g. some linux library or application like linuxtv-dvb-apps or w_scan)
you don't have to do everything mentioned in the howto. it's a HowTo not a HaveTo

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Ahh OK. So I guess I'm done then. I haven't installed the SDE on my Archos yet, but what's the final 'thing' that came out of this procedure that I'll be placing on the tablet?
Also I don't have an microSD card yet, and I know there was talk of putting stuff on there - can this be done using just the internal memory (8 GB for me)?

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you have to install the SDE to install a custom kernel. follow this guide: http://forum.xda-developers.com/showthread.php?p=10157349#post10157349

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Yeah I saw that guide, my question is where is the zImage and initramfs.cpio.gz that I assume was part of the compiling I just did? And also if a microSD card is needed for any of this?

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no microsd is needed
initramfs.cpio.gz can be extracted from current installation ( /dev/mmcblk0p1 -> init ), read this: http://forum.xda-developers.com/showthread.php?t=880321&page=5
zImage is compiled at this location: $ARCHOS/gen8-gpl-froyo/buildroot/linux/arch/arm/boot/zImage

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Shouldn't it be
Code:
cross make kernel-build
?
Here I have to use cross, which makes sense to find gcc arm binaries.

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No you don't. In case of building stuff which comes with the gen8-gpl-froyo.tgz (e.g. kernel) the env vars are set up by the supplied makefiles

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chulri said:
No you don't. In case of building stuff which comes with the gen8-gpl-froyo.tgz (e.g. kernel) the env vars are set up by the supplied makefiles
Click to expand...
Click to collapse
If I don't use cross, here is what I get:
[email protected]:~/archos$ make kernel-build
make -C gen8-gpl-froyo/linux mrproper
make[1]: arm-linux-gcc: Command not found
make[1]: Entering directory `/home/ubuntu/archos/gen8-gpl-froyo/linux'
make[3]: arm-linux-gcc: Command not found
But using cross it compiled fine, though I followed carefully your directions !

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Apparently I was too frightened by the error messages, since it does work in the end
Thank you very much, hope some good things come from this !
Cheers !

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desiresush said:
Apparently I was too frightened by the error messages, since it does work in the end
Click to expand...
Click to collapse
Yeah it's just an annoying bug, it doesn't hurt because "mrproper" only cleans the build directory and doesn't need compiler at all

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2.6.29 kernel for Froyo?
Does anybody know, why Archos releases the SDK with a 2.6.29 kernel?
Shouldn't 2.2 Froyo be a 2.6.32 kernel?