Benutzer-Werkzeuge

Webseiten-Werkzeuge


jornada_j720_linux49

Linux on the Jornada 720

Attempt to get a Linux Kernel 4.8.7 and Debian 9 working on the J720

I started with a fresh 4.9.210 Kernel. https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/linux-4.8.7.tar.gz

The problem is that ARMv4 CPUs like the SA-1110 have no BX instruction, which are only available on newer ARMv4t CPUs. So you can not run any newer userland like Debian armel. Some guys from the arm-platforms community found a clever solution and wrote a workaround to emulate this instruction on older ARMv4 CPUs. https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=arm/netwinder&id=6d833b52d0591b47ee65ef2808c459a99f1d37ec

Here is the patch: bx_instruction.zip

I compiled the kernel on a Ubuntu 18.04 machine.

- get the tools for compiling the kernel

 $ sudo apt-get install fakeroot build-essential devscripts libncurses5 libncurses5-dev
 $ sudo apt-get build-dep linux

- get gcc for cross-compiling ARM

 $ sudo apt-get install gcc-arm-linux-gnueabi

- download the kernel source code

 $ wget https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/linux-4.8.7.tar.gz
 $ tar xf llinux-4.8.7.tar.gz

- now you have to download the patch and apply it to the kernel source

 $ cd linux-4.8.7
 $ wget http://www.sp-net.at/wiki/lib/exe/fetch.php?media=bx_instruction.zip
 $ unzip bx_instruction.zip
 $ patch -p1 < bx_instructions.patch

- make config from arch/arm/configs/jornada720_defconfig

make ARCH=arm jornada720_defconfig

- edit the .config and add set CONFIG_PCMCIA_SA1111=y CONFIG_AEABI=y and CONFIG_OABI_COMPAT=y

- for Debian 9 and systemd we need to set more options: CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y CONFIG_TMPFS=y CONFIG_TMPFS_POSIX_ACL=y CONFIG_CGROUPS=y CONFIG_AUTOFS4_FS=y

- compile the kernel

$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- zImage

And we are done!

Remember to add „rootdelay=2“ to the kernel command line in the bootloader!

jornada_j720_linux49.txt · Zuletzt geändert: 2020/03/04 09:24 von stefan