hybrid debian/ arch linux image

[cedric]

Hi All,

i have tried to  run an Arch linux image on my A20-OLinuXino-MICRO-4GB. This image was unstable, the system frooze 3 times in a few hours. The image I've used (revision 2)is here:
https://www.olimex.com/forum/index.php?topic=1856.msg8745#msg8745

The official debian image from here is rock-solid, it has never frozen sofar:
http://olimex.wordpress.com/2014/03/07/building-a20-olinuxino-micro-debian-image-with-hardware-accelerated-video/
https://drive.google.com/file/d/0B-bAEPML8fwlX2tYS2FmNXV5OUU/edit?usp=sharing
A20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_Video_accel_release7.7z

I wanted to see if it was the uBoot, kernel or scrip.bin that's causing the freezes, so I have prepared an uSD card with uBoot, image and script.bin from debian, and the rest from arch linux. I now have a system that boots, and can be reached from ssh. It does not create an image on my HDMI TV.

Here are the steps I have taken:
1)download A20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_Video_accel_release7.7z
https://docs.google.com/file/d/0B-bAEPML8fwlX2tYS2FmNXV5OUU/edit?pli=1

2) write the image to a SD card. I have used a 32GB card, but only 4 GB is used.
$ 7z e A20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_Video_accel_release7.7z
# dd if=A20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_Video_accel_release7.img of=/dev/mmcblk0

3) mount /dev/mmcblk0p2 en leeg de partitie
# mount /dev/mmcblk0p2 /mnt
# cd /mnt
# rm -rf *

4) untar ArchLinuxARM-sun7i-latest.tar.gz:
# tar -C /mnt -xvf ArchLinuxARM-sun7i-latest.tar.gz

I forgot to restore the kernel modules from debian, maybe when I do that I get an image on the HDMI screen.

Kind regards,
cedric

[cedric]

I now have copied the modules from debian. Now my digitenne receivers work, but I don't see anything on my screen yet, and I don't have /dev/fb0

Kind regards,
Cedric

[cedric]

I have figured out when the image freezes. The culprit was cpupower. After installing it, the system crashes when it changes frequency. It also crashed when cpupower frequency-info is executed.

After disabling cpupower, my arch system has not crashed yet. Before installing spupower, it has also not crashed.

So it turns out I don't have to go through the trouble of making an arch linux image myself.

Kind regards,
Cedric

[cedric]

I have figured out why there is nothing on the screen. The solution is here:
http://linux-sunxi.org/Display

in the .config of the kernel, the following lines have to be set to 'y'
ONFIG_FB_SUNXI=y
CONFIG_FB_SUNXI_LCD=y
CONFIG_FB_SUNXI_HDMI=y

CONFIG_FRAMEBUFFER_CONSOLE=y
CONFIG_FONT_8x8=y
CONFIG_FONT_8x16=y

Then the kernel can be build like described here:
http://alarma20.wordpress.com/2013/09/13/howto-build-arch-linux-arm-for-a20-olinuxino-micro/

Kind regards,
Cedric