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

===================================================================== DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office@denx.de =====================================================================

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

On Thursday 24 April 2008, Grant Likely wrote:

...

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?

You're hitting a limitation of current u-boot. It doesn't know how to allocate more space in a device tree blob. Try passing "-S 8192 -R 16" to dtc.

And don't forget "-b 0" for the boot CPU number.

Best regards, Stefan

===================================================================== DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office@denx.de =====================================================================