[U-Boot-Users] Running Linux from ARCH=powerpc on Sequoia board

[Larry Johnson <lrj@acm.org>]

Stefan Roese wrote:
> Hi Larry,
> 
> On Tuesday 22 April 2008, Grant Likely wrote:
>>> Currently, I can build "zImage" for Sequoia using the powerpc
>>> architecture, and load it using U-Boot without a separate FDT binary.
>>> Is this the best way to run a Linux from the powerpc tree?
>> Sorry, I don't understand what you're asking.
>>
>> There are two way to boot a Linux image from arch/powerpc.
>>
>> 1) build a uImage and get u-boot to pass a device tree blob (if your u-boot
>> had device tree support)
>> 2) build a cuImage which wraps the device tree in the kernel image.
> 
> Correct. Personally I prefer 1), since it makes the Linux ports easier. No 
> bootwrapper is needed in this case. And all the "infrastructure" for fdt 
> enabled U-Boot images for 4xx is available. Please take a look at 
> sequoia.c/.h and search for CONFIG_OF_LIBFDT.
> 
> Just let me know if this is not clear or if you have additional questions.
> 
> Best regards,
> Stefan
> 
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Thanks Stefan, Grant, and Wolfgang for your comments.  Method 2 is
working for me, as it turns out that files "cuImage.sequoia and "zImage"
are identical.

I'd prefer to use method one.  Here's an abbreviated listing of what I
get when I try.

<listing>
=> tftp 200000 sequoia/uImage
[...]
Bytes transferred = 1497002 (16d7aa hex)
=> tftp 1000000 sequoia/sequoia.dtb
[...]Bytes transferred = 6659 (1a03 hex)
=> run ramargs addmtd addip addide addtty; bootm 200000 ${ramdisk_addr} 1000000
## Booting kernel from Legacy Image at 00200000 ...
   Image Name:   Linux-2.6.25-rc8-01262-g80afde7
   Image Type:   PowerPC Linux Kernel Image (gzip compressed)
   Data Size:    1496938 Bytes =  1.4 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Uncompressing Kernel Image ... OK
## Flattened Device Tree blob at 01000000
   Booting using the fdt blob at 0x1000000
## Loading init Ramdisk from Legacy Image at fc400000 ...
   Image Name:   sequoia Ramdisk Rev 006
   Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
   Data Size:    19409859 Bytes = 18.5 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Loading Device Tree to 007fe000, end 007ffa02 ... OK
fdt_chosen: FDT_ERR_NOSPACE
ERROR: /chosen node create failed - must RESET the board to recover.

U-Boot 1.3.2-00497-g58c5376 (Apr 23 2008 - 16:24:13)
[...]
</listing>

The file "sequoia.dtb was created by 

$dtc dts/sequoia.dts -O dtb -o sequoia.dtb

Can anyone tell me what went wrong?

Best regards,
Larry