INdT and Mamona28 Aug 2007 06:15 pm

Thinking to leave the main flash memory free for Mamona tests I looked for a way to have dual boot in the N800. Then I found a good documentation explaining how to easily boot from MMC card.

The only step that I skipped was the “How to install a dual boot menu?”.

To use the system in memory card I’ve edited the initfs manually  to access directly the partition created in the memory card. The only thing that I did was to add the code below in the begin of boot() function in linuxrc of initfs (My last post  explains how to edit and flash the initfs in your pc).

load_mmc_modules
root_dev=mmcblk0p2
root_dev_name=”MMC”
root_dev_set=1
root_fstype=”"
root_fsoptions=”"

As you can easily notice it is hard coded. Actually I’m not using a real dual boot because when testing mamona I need to flash the kernel too, so I prefer to flash a different initfs for mamona every time instead of have to press a button during the boot.

However it is possible to have a dual boot changing the begin of boot() function of linuxrc in initfs to be like that:

boot()
{
load_wlan_module
if ! grep -q new_root /proc/mounts; then
text2screen -t “Press any key for MMC boot” -H left -y 80 -s 2 -B 0xffff
key_pressed 1
if [ $? -ne 0 ]; then
load_mmc_modules
root_dev=mmcblk0p2
root_dev_name=”MMC”
root_dev_set=1
root_fstype=”"
root_fsoptions=”"
fi
mount_device “$root_dev”
fi
if [ $? -ne 0 ]; then
return 1
fi

Or following that step that I haven’t tried.

It is important to clarify that when you flash only the initfs and/or the kernel you don’t loose any data in your main flash memory or in your MMC card.

Another important thing to say is about performance. I’ve been using it for more than a week from  internal MMC slot and couldn’t notice any lost of performance when compared to a system booting from main flash memory.

Are you curious about Mamona booting on N800? This is a topic for another post…

One Response to “N800: Dual boot / Booting from memory card”

  1. on 19 Nov 2007 at 5:46 am Adenilson Cavalcanti

    Rodrigo

    I’m trying to download the mamona SDK file using the url provided in the Mamona’s wiki (http://dev.openbossa.org/trac/mamona/wiki/MamonaInstallationGuide), but it seems that its a dead link: http://dev.openbossa.org/mamona/tools/debootstrap/mamona

    Do you known of another source to download it?

    Best regards

    Adenilson

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