I am not sure if I understand correctly. But Looks like you are not passing the device tree along with kernel image and RAMDISK(you may not need it if you are using NFS mount). You boot command should some what look like this "bootm kernel_addr ramdisk_addr devtree_addr" or "bootm kernel_addr - devtree_addr" . If you are already doing that I would check my bootargs for correct params.
-----Original Message----- From: linuxppc-dev-bounces+tmarri=amcc....@ozlabs.org [mailto:linuxppc-dev-bounces+tmarri=amcc....@ozlabs.org] On Behalf Of Yigal Goldberger Sent: Thursday, April 02, 2009 1:06 PM To: linuxppc-dev@ozlabs.org Subject: early kernel debugging Hi All, I'm using u-boot to boot kernel 2.6.24.2 on a powerpc based board . I see that after uncompressing the kernel it hangs. I found a location (System.map) I think corresponds to the __log_buf (my SDRAM starts at physical address 0 (and u-boot performs -> Load Address: 00000000 Entry Point: 00000000) . So I just removed the leading C0xxxxxx from the address leaving xxxxxx . And that's where I looked . I did see 2 error messages (though they were somewhat corrupt) the first designated a memory fault and the second a kernel oops at some address. I looked this address up on System.map and it's somewhere inside prom.c in of_scan_flat_dt( ) . I have a few question at this point : A)Am I looking at the right memory location for __log_buf ? B)What is printed to the buffer (printk's of what verbose level ?) C)In a previous kernel version 2.6.14 I don't remember explicitly using a flat device tree or pointing at such a tree through the bootm command) , but I used the ARCH=ppc then as opposed to ARCH=powerpc Now . I see a lot of stuff regarding the need to provide such a data structure upon booting via bootm .Do I need to explicitly prepare such a data structure and provide a pointer to it via bootm ? Might this be the cause for this early hang ? Best Regards, Yigal Goldberger. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev