Xperia Z Ultra Hot Boot with DTB? - Sony Xperia Z Ultra

Hi,
I'm fairly green when it comes to Android devices, but my understanding is that when using "fastboot," I ought to be able to select "hot boot" a kernel and ramdisk using the "boot kernel <ramdisk.gz> command. However, for my Xperia Z Ultra, I'm finding that when I attempt this, I am told:
"FAILED (remote: dtb not found)"
A bit of research indicates that this probably refers to a "device tree blob", something which I understand is used to inform the kernel as to how to access devices (http://xillybus.com/tutorials/device-tree-zynq-1). However, I can't find any information pertaining to the inclusion of a "dtb" when using fastboot.
In my probing of various "sin" files, I've managed to extract the kernel.sin for the HK 461 amd 471 ROM versions. They present me with an elf file. This elf file, in turn, can be extracted into three files. The kernel image, the ramdisk gzip and a ".3" file, which I can only assume is the dtb.
My question is whether it is possible to reassemble these files into an elf, and subsequently a sin file so that I can then put this back into the original ROM ftf. Failing this, I'd like to be able to simply hotboot the kernel and a modified ramdisk (that leaves / and /system mounted as rw and runs adb as "root" rather than "shell").
I'm not asking for a handout or a painstakingly written HOWTO, just a pointer in the right direction, if possible.
Interestingly, if I try to simply "hot boot" the extracted elf, it seems to upload perfectly to the phone, but then the phone hangs when trying to boot:
Code:
C:\adt-bundle-windows-x86_64-20130729\sdk\platform-tools>fastboot.exe -i 0x0fce boot D:\kernel-461.elf
creating boot image...
creating boot image - 8663040 bytes
downloading 'boot.img'...
OKAY [ 0.283s]
booting...
FAILED (status read failed (Too many links))
finished. total time: 413.509s
The "FAILED" is reported after I simply unplug the phone. At this point, the phone is very much locked up with the blue LED illuminated. After a few panicked moments, I realised that Vol-Up + Power is a force-reset key combination (it causes the vibration motor to pulse three times, then reboots).
For completeness, here's what happens when I try "hot booting" the extracted kernel and my custom ram disk:
Code:
C:\adt-bundle-windows-x86_64-20130729\sdk\platform-tools>fastboot.exe -i 0x0fce boot D:\kernel-461.elf.Image D:\ramdisky.gz
creating boot image...
creating boot image - 8329216 bytes
downloading 'boot.img'...
OKAY [ 0.274s]
booting...
FAILED (remote: dtb not found)
finished. total time: 0.322s

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Chinese, all i see here i chinese One thought though, wouldn't the guys over at the Xperia Z forum be at any assistance? They are working with Sony hardware after all, and maybe they can give you some tips and ideas? I'm just thinking here though
Anywho, keep it up. It's only a matter of time until you crack the code!

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ShALLaX said:
Hi,
I'm fairly green when it comes to Android devices, but my understanding is that when using "fastboot," I ought to be able to select "hot boot" a kernel and ramdisk using the "boot kernel <ramdisk.gz> command. However, for my Xperia Z Ultra, I'm finding that when I attempt this, I am told:
"FAILED (remote: dtb not found)"
A bit of research indicates that this probably refers to a "device tree blob", something which I understand is used to inform the kernel as to how to access devices (http://xillybus.com/tutorials/device-tree-zynq-1). However, I can't find any information pertaining to the inclusion of a "dtb" when using fastboot.
In my probing of various "sin" files, I've managed to extract the kernel.sin for the HK 461 amd 471 ROM versions. They present me with an elf file. This elf file, in turn, can be extracted into three files. The kernel image, the ramdisk gzip and a ".3" file, which I can only assume is the dtb.
My question is whether it is possible to reassemble these files into an elf, and subsequently a sin file so that I can then put this back into the original ROM ftf. Failing this, I'd like to be able to simply hotboot the kernel and a modified ramdisk (that leaves / and /system mounted as rw and runs adb as "root" rather than "shell").
I'm not asking for a handout or a painstakingly written HOWTO, just a pointer in the right direction, if possible.
Interestingly, if I try to simply "hot boot" the extracted elf, it seems to upload perfectly to the phone, but then the phone hangs when trying to boot:
Code:
C:\adt-bundle-windows-x86_64-20130729\sdk\platform-tools>fastboot.exe -i 0x0fce boot D:\kernel-461.elf
creating boot image...
creating boot image - 8663040 bytes
downloading 'boot.img'...
OKAY [ 0.283s]
booting...
FAILED (status read failed (Too many links))
finished. total time: 413.509s
The "FAILED" is reported after I simply unplug the phone. At this point, the phone is very much locked up with the blue LED illuminated. After a few panicked moments, I realised that Vol-Up + Power is a force-reset key combination (it causes the vibration motor to pulse three times, then reboots).
For completeness, here's what happens when I try "hot booting" the extracted kernel and my custom ram disk:
Code:
C:\adt-bundle-windows-x86_64-20130729\sdk\platform-tools>fastboot.exe -i 0x0fce boot D:\kernel-461.elf.Image D:\ramdisky.gz
creating boot image...
creating boot image - 8329216 bytes
downloading 'boot.img'...
OKAY [ 0.274s]
booting...
FAILED (remote: dtb not found)
finished. total time: 0.322s
Click to expand...
Click to collapse
yes, same thing in here (it seems newer kernel with dtb)
how to extract them correctly and re-pack to work?
http://forum.xda-developers.com/showthread.php?t=2428117

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hkfriends said:
yes, same thing in here (it seems newer kernel with dtb)
how to extract them correctly and re-pack to work?
http://forum.xda-developers.com/showthread.php?t=2428117
Click to expand...
Click to collapse
Why extract it at all? Sony has released the kernelsourcecode and we can create a dtb from scratch. Btw dtb and kernel are corresponding, so better not always use 475 dtb for ever!
So you guys better grab the kernel opensource and compile it sourself instead breaking heads on howto extract.
See our repos custombootimg.mk for the mkbootimg parameters once you compiled dt.img
Regards
Gesendet von meinem C6833 mit Tapatalk 4

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I wasn't looking at how to extract it, but how to include it in the ELF. I'll take a look at the mk file, got a link?
Sent from my GT-I9500 using xda app-developers app