On Sunday 20 December 2015 18:43:34 Michael Ströder wrote:
> > The latest update to kernel 4.3.0 for RPi1 ruined the system. It does not
> > start anymore. The error message on the screen said:
> > File not found dtb.bcm2835-rpi-b.dtb
> 
> Since a couple of kernel updates and only on some systems I have to manually
> copy the fimware files into /boot/dtb/ to make it work again.
> 
> Ciao, Michael.

Most probably your system is not properly updated, which happens as not 
everything is updated automatically, unfortunately.

As of today, the blueprint for booting looks as follows:

- RPi loader (bootcode.bin) on the first partition (FAT16) is loaded and 
started.
- Reads Config.txt, kernel=u-boot.bin
- RPi loader starts u-boot

------ handover -----

- u-boot starts, reads default environment
- environment contains command to find first bootable partitions [1]
  -> this yields the second, ext3 boot partition
- bootable partion is scanned for boot.scr
- boot.scr is loaded and executed
- boot.scr contains
 - the path to the fdt file (e.g. dtb/bcm2835-rpi-b.dtb)
 - the path to the kernel (zImage)
 - the path to the initrd (initrd)
 - the kernel cmdline arguments (root=...)
- u-boot loads the fdt file
- u-boot loads the kernel
- u-boot loads the initrd
- u-boot appends the initrd address to the fdt
- u-boot executes the kernel
----

* The boot.scr is only created once during kiwi image creation, so this may be 
outdated. You can view its contents with:
 $> tail -c +72 /boot/boot.scr
* u-boot.bin itself has to be copied to the FAT partition manually. 
* The dtbs are multiversion enabled since a few weeks. You should remove the 
old /boot/dtb/ directory and reinstall the latest dtb-bcm2835 rpm, /boot/dtb 
should be a symlink to the versioned dtb directory afterwards.

Kind regards,

Stefan


[1] as of u-boot 2015.04-rc5

-- 
Stefan Brüns  /  Bergstraße 21  /  52062 Aachen
home: +49 241 53809034     mobile: +49 151 50412019
work: +49 2405 49936-424

Attachment: signature.asc
Description: This is a digitally signed message part.

Reply via email to