Dual kernel choice at boot time

[opengl1971]

I realized that there isn't a way of switching native resolution like what we do in windows but
Is there a way or firmware to choose between kernels at boot time (720p or 1080p kernels) ?
The thing is 1080p is suitable for viewing images or videos but 720p is more suitable for games
As it puts less load.

[pestul]

I realized that there isn't a way of switching native resolution like what we do in windows but
Is there a way or firmware to choose between kernels at boot time (720p or 1080p kernels) ?
The thing is 1080p is suitable for viewing images or videos but 720p is more suitable for games
As it puts less load.

That's a really good idea. I'm more than happy with a 720p kernel, but I see how this could be of use to some.

[Finless]

There is a way to do this (I think)!

The idea is you flash the other kernel to the recovery area. Then using reboot APP, reboot to recovery and it should boot with the other kernel. This is how Picunutu works. I have not tested it myself using Android kernels though so you guys can try it and let us know.

Bob

[opengl1971]

Thanks bob for you answer , i am a little confused about the picunutu thing , i tried before and bricked My UG007 , but revived it back by using a tutorial some where here in the forums .

Basicly when i booted into recovery i got stucked In the picunutu console and wasnt able To boot to android again and my pc wasn't able to identify the tv stick again so i couldn't Reflash it , when i checked the picunutu forums here i found many people got stuck in linux Like me , i saw one user said that you have to boot to boot loader not recovery as i did , Otherwise you will get stuck in linux:

http://www.freaktab.com/showthread.php?3609-Linux-MK808-UG802-MK802-III-PicUntu-0-9-RC-2-2-w-Finless-1-6-ROM-Dual-Boot-Windows-Guide/page4

(Post no.77)

But i realize that in our case the 2 kernels are android so the outcome may be different.

So bob can you please tell me which reboot should i use (in the case you mentioned of dual android kernel boot ) : boot loader or recovery , i would Try it my self and see but i am afraid i may brick my stick again , Really appreciate your idea.

[Mandrake2]

$cript app (playstore), we can make a script for change kernel.img in mtdblock with "cat" command or "dd" and then reboot.
After I try to write the script.

[opengl1971]

I tried flashing the 1080p kernel into recovery partition and i bricked my device again ,
it didn't even boot once And my pc won't recognize it so it can't be reflashed , i suspect that the 1080p or 720p kernels are a little big for the recovery partition , anyway i warn every one not to use this method as it bricks the tv stick.

I flashed it all at the same time , meaning that i replaced recovery.img with kernel1080.img left
All the rest as default and flashed , it may be better if i flashed normally with 720p kernel
And let the device reboot first then flash the 1080p kernel into the recovery partition , just may be
I don't know.

Also i flashed with finless 1.7a which have both 1080p and 720p kernels , i don't know if Other versions will Work.

[Finless]

You should not have flashed everything. You should have only flashed kernel1080.img to recovery space!
The reason you bricked is you also flashed misc.img. This causes the boot loader to boot to recovery and format /data /cache, etc. which it could not do since recovery is gone now. So that's why.

After flashing kernel1080.img to recovery space it should have booted normally and used kernel720.img as normal.

Finally, Petrus is working on a APP to write MTD areas while Android is running. So we may have an easy solution very soon for you.

Bob

[opengl1971]

$cript app (playstore), we can make a script for change kernel.img in mtdblock with "cat" command or "dd" and then reboot.
After I try to write the script.

Mandrake2 can you please explain in more details as i never wrote an android script and i don't know what mtdblock is , sorry to disappoint you .

[opengl1971]

Sorry bob , my mistake.
I wolud like to thank you , Mandrake2 and Petrus for your help and info , really very
Thankful.

[opengl1971]

A little update:

I tried again by flashing only the 1080p kernel into the recovery space then rebooted which gave the Following results:

1-Reboot to recovery which bricked the stick (was stuck in a flashing logo screen which doesn't go away by unplug / replug the usb cable) , at this point the stick wasn't recognized By the pc so it wasn't possible to re-flash it , so it was basically bricked.

2-Reboot to boot loader which gave a blank screen , but once i unplugged then plugged the Usb cable The stick booted normally into the 720p kernel , so it didn't work but at least it Didn't brick the stick.

So i guess if there is no other suggestions the Petrus' App is my last hope right now.

[leolas]

Re: Dual kernel choice at boot time

Maybe only a kernel is not enought, I think to do that we must have a boot with a kernel embeded in recovery partition.

[ididmytime]

I was actually going to suggest the same thing, but didn't as I am under no illusion of how difficult this would actually be. Although we do have a CWM option to do this before boot, an APP to reboot to another kernel is much easier for people, and I am sure it would be greatly appreciated by the community.

Good luck Petrus.

[opengl1971]

I agree with ididmytime , as we need a simple and easy solution to do this
For people who don't know how to write scripts or modify kernels.

Having 2 kernels at the same time without the need to re-flash will serve many purposes.

[opengl1971]

Maybe only a kernel is not enought, I think to do that we must have a boot with a kernel embeded in recovery partition.

I have a question here :
How comes picanutu works with only flashing its kernel to the recovery space
While android can't and needs a boot with the kernel ?

[leolas]

Re: Dual kernel choice at boot time

I have a question here :
How comes picanutu works with only flashing its kernel to the recovery space
While android can't and needs a boot with the kernel ?

Not exactly the same, picuntu flash a kernel with a initramfs, dont know exactly what is in this, cause I started with picuntu 2 days ago, if you flash a kernel alone picuntu don't works.