mpc 860 boot linux2.6.23 problem
Scott Wood
scottwood at freescale.com
Thu Oct 18 05:15:28 EST 2007
Jochen Friedrich wrote:
> Hi Scott,
>
>> I just pulled Wolfgang's latest u-boot tree, and I don't see any fdt
>> or ft_ calls in cpu/mpc8xx, nor in any 8xx board that I recognize.
>>
>> I may have been unclear in that I was talking about device tree
>> support in u-boot, not the kernel. Obviously there's device tree
>> support in the kernel, as evidenced by my reference to using cuImage.
>>
>
> Can u-boot work on dtb trees embedded in an cuImage, at all?
No. If you want that, you need to use a normal uImage.
> How would command line arguments work without a chosen
> node?
The bad old way: argument registers and the bd_t. The bootwrapper fills
in /chosen/bootargs and other things based on that.
It's just for compatibility; use uImage if you can.
> I tried to boot a mpc823 using the 3 argument mboot command.
> u-boot processed the dtb and added the chosen node correctly,
> however the kernel immediately oopsed with unable to access
> virtual memory when accessing the dtb memory as this memory
> was not contained in the kernel MMU space.
Make sure your version of u-boot understands the new bindings for things
like brg frequency, or (less preferred) set it manually in your dts.
-Scott
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