Compile lab126 kernel

[knc1]

Originally Posted by pepijndevos

I set the initramfs to an empty string, so i don;t think so.
I don't have a tequila .list, there is a joshime .list though, maybe I could try that.

Options to the kernel? No idea. I gave ARCH and CROSS_COMPILE to make. The rest is probably the defaults.

I don't know that it doesn't run, I just know the Kindle doesn't start with that kernel flashed to it.

Network console? No?! How does that work? I'll read the configs a bit...

kernel-source_version-number/Documentation/**

Kernel command line options -
The kernel is a regular C program - just like an application program with: main(argc, **argv).

The stored options for start-up come from:
Passed by the loader (in this case, u-boot) ;
In newer versions of the kernel, stored in the kernel at build-time.
(NO, don't ask me if your version does that, I don't recall what version the "stored command line" was added.)

When passed by u-boot, u-boot has them stored in its environment.
Same place it keeps its other scripting strings.

If you don't have the list (or the directory) for the initramFS - make one of your own choosing.
Starting point: "Early Userspace" in the kernel source documentation tree.
AND/OR
Extract the initramFS from one of the factory kernel images.
It will most likely be a gzip'd cpio file appended to the kernel.
(gzip'd cpio because this is a fairly old kernel version)

Your primary help source is the /Documentation/** tree in the source file.

Other stuff that might give you a feel for what you need to do:
http://www.christian-hoff.com/?p=16

There are some technical differences between the boot image used by MIPS and the one used by ARM, but the principles are the same:
http://minimodding.com/RecipesIndex
http://minimodding.com/SnippetsIndex
http://minimodding.com/SystemRescue
You can probably find that site's owner lurking around here, somewhere.

[pepijndevos]

I'm sorry, how do I see if it booted at all with a (usb?) cable? Only thing I can think of is to check lsusb.

In fact, I do have the old kernel on there again.

I found this: https://www.mobileread.com/forums/sho....php?p=2187253
And this: http://lxr.linux.no/linux+v2.6.32/Do...netconsole.txt

But I have no USBNET variable, nor any idea what to put in it. So I doubt there is any interface to connect to until the userspace sets up wifi and usb networking.

Oh, and i tried to use the joshime .list, but that produced a lot of errors.

[knc1]

Both u-boot and the kernel can set up wifi and networking.
That is how it "network boots".
Watch your wireless router for a connection attempt (you might have to set ip= in the kernel command line).

Since the only way to communicate with u-boot is via its serial port - -
You are sort-of SOL without the serial cable.
Ref:
https://wiki.mobileread.com/wiki/Hard...ex#Serial_Port
Read the first caption line to that section please.

[twobob]

I gave chris a bump about this thread FWIW.
He has made available the likely changes needed for kindle touch support now. on the original off-site thread. Many thanks to Chris on that one.


Hope you get this sorted mate.

[knc1]

Originally Posted by pepijndevos

Oh, and i tried to use the joshime .list, but that produced a lot of errors.

There are alternatives, but everything requires more documentation reading.

Also, studying the start-up scripting in the factory initramFS image should help get a handle on what you want the kernel to do on start-up.

Specific directions at this point?
I think Lewis Carroll said it best:
http://philosiblog.com/2011/07/13/if...e-youre-going/

[pepijndevos]

Yea, ordered a serial cable already. But if this netconsole can save me cracking my kindle open, that would be sweet.

I've been mailing with Chris, trying to run his OTG kernel. I guess he knows what it takes to compile a K4 kernel.

I guess I need to copy the initramfs from the stock kernel. His OTG kernel is similar in size to the stock kernel, IIRC.

[knc1]

Why don't you read the scripting in the initramfs?
It might provide you with information on how to make things work the way you want them to.
You certainly will not know any less than before you read it, since it can't suck the knowledge you already have out of your head.

Having "network console" built into the kernel will not do you much good when you need to communicate with u-boot to change kernel command line options **before** the kernel is loaded and ran.

[choff]

Hi all,

it is true that you cannot run the kernel without an initramfs.

So you need to have an initramfs. But where can you get one?

The easiest method is to use the initramfs of the Amazon kernel as a template. Normally no modifcations to the Amazon initramfs are necessary, so you will just have to repack that initramfs. The resulting cpio archive can be used as input CONFIG_INITRAMFS_SOURCE.

I have updated the compilation post in order to reflect this.

There are also new detailed instructions available on how the initramfs can be extracted from the Amazon kernel. I added this information this post: http://www.christian-hoff.com/?p=16

Hope this helps!

And I wish you good luck with your compilation attempts.

Regards,

Chris

[knc1]

Originally Posted by choff

it is true that you cannot run the kernel without an initramfs.
- - - - snip - - - -
Regards,

Chris

That is not true in the general case.

It might be true for your current application of a kernel to a specific device, but your post did not include that information.

The only requirements to "run a kernel" is:
a file system to mount as the root file system,
a program to run as process ID 1,
/dev/console,
as a result of the second requirement, often also:
/dev/null

There may be additional requirements of what process you run, but the kernel itself will run with the above requirements met.

[geekmaster]

Originally Posted by choff

Hi all,

it is true that you cannot run the kernel without an initramfs.

So you need to have an initramfs. But where can you get one?

The easiest method is to use the initramfs of the Amazon kernel as a template. Normally no modifcations to the Amazon initramfs are necessary, so you will just have to repack that initramfs. The resulting cpio archive can be used as input CONFIG_INITRAMFS_SOURCE.

I have updated the compilation post in order to reflect this.

There are also new detailed instructions available on how the initramfs can be extracted from the Amazon kernel. I added this information this post: http://www.christian-hoff.com/?p=16

Hope this helps!

And I wish you good luck with your compilation attempts.

Regards,

Chris

Welcome to the "2600 club".