swarren
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RPi 3 kernel8.img?

Tue Mar 01, 2016 5:59 am

For the RPi 0/1, the VC firmware loads kernel.img, and on the RPi 2 it loads kernel7.img (or at least tries that first). Does/will the RPi 3 try to load kernel8.img first? That would be very useful in order to create a single SD card containing a U-Boot for all Pis, which will need 3 different versions for the 3 different ARM architectures.

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DougieLawson
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Re: RPi 3 kernel8.img?

Tue Mar 01, 2016 8:30 am

There's no kernel8.img on the Jessie SDCard I've written ready for when my Pi3B arrives. The new stuff is a device tree file for bcm2710. I'm assuming it will load kernel7 until the RPF folks decide whether to move to a 64-bit kernel.
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Re: RPi 3 kernel8.img?

Tue Mar 01, 2016 9:55 am

Some of us are a bit more impatient than that. :)

I want to get arm64 versions of Debian or Arch running ASAP. Is 'kernel8.img' the correct filename?

djrose
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Re: RPi 3 kernel8.img?

Tue Mar 01, 2016 10:48 am

I've just hunted through the start.elf file on the latest Jessie image. I can only see kernel.img and kernel7.img being referenced - No mention of a kernel8.img.

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Re: RPi 3 kernel8.img?

Tue Mar 01, 2016 10:54 am

I'll see if I can find out what the RPF are up to with regards to 64bit.
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Fidelius
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Re: RPi 3 kernel8.img?

Tue Mar 01, 2016 11:09 am

jamesh wrote:I'll see if I can find out what the RPF are up to with regards to 64bit.
Thank you, JamesH !

swarren
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Re: RPi 3 kernel8.img?

Sun Mar 06, 2016 5:25 am

It might be even more useful if the FW loaded kernel8-32.img if booting in 32-bit mode and kernel8-64.img if booting in 64-bit mode (with boot mode still selected via the config.txt option for that).

dwelch67
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Re: RPi 3 kernel8.img?

Sun Mar 06, 2016 4:44 pm

How would the bootloader (start.elf) know to pick the 32 from the 64 if both are present? config.txt?

swarren
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Re: RPi 3 kernel8.img?

Sun Mar 06, 2016 4:49 pm

Yes. There's already an option in config.txt to select between 32- and 64-bit mode. I don't recall the exact name right now; something like arm_flags. dom mentioned it in another thread on this forum IIRC (search topic titles for AArch64 IIRC).

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Re: RPi 3 kernel8.img?

Sun Mar 06, 2016 5:01 pm

swarren wrote:Yes. There's already an option in config.txt to select between 32- and 64-bit mode. I don't recall the exact name right now; something like arm_flags. dom mentioned it in another thread on this forum IIRC (search topic titles for AArch64 IIRC).
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