Trouble with 2.6.16 on ppc8xx ?

Trouble with 2.6.16 on ppc8xx ?

[David Jander]

Hi all,

I just cg-update'd to the HEAD of the denx 2.6.x kernel tree (2.6.16 as 
released).
Our board-support stuff was succesfully moved along from 2.6.14 (when 
everything but the SCC3 and SCC4 uarts worked just fine).
I compiled a kernel without any special drivers, just console on ttyCPM0, but 
after "Uncompressing Kernel Image ... OK" there is no more output and no 
further activity on ethernet (it should boot from nfs-root) or any other 
device.

After "cg-seek DENX-v2.6.15; make clean uImage", it works again (everything 
seems fine, system boots).

Our board is based on a MPC852T and until now we used "MPC86X" as the 
BOARD_CHIP_NAME and it worked just fine with 2.6.14 and 2.6.15, but not with 
2.6.16 as described above.

When doing "cg-diff" and carfully examining it's output, I can only see our 
board-support stuff (not very much, not very special) and some custom drivers 
that are disabled anyway.

Any clue about where to start looking?

I didn't find any suspicious changes in arch/ppc/mm, arch/ppc/syslib and 
arch/ppc/kernel. Neither in drivers/serial/cpm_uart.

Which change from 2.6.15 to 2.6.16 could have broken 8xx support for us?

Is there perhaps a known issue with 2.6.16 and ppc8xx I am unaware of?

Greetings,

-- 
David Jander

Re: Trouble with 2.6.16 on ppc8xx ?

[Marcelo Tosatti]

Hi David,

On Fri, Apr 14, 2006 at 10:50:56AM +0200, David Jander wrote:
> 
> Hi all,
> 
> I just cg-update'd to the HEAD of the denx 2.6.x kernel tree (2.6.16 as 
> released).

Is it a vanilla 2.6.16?

> Our board-support stuff was succesfully moved along from 2.6.14 (when 
> everything but the SCC3 and SCC4 uarts worked just fine).
> I compiled a kernel without any special drivers, just console on ttyCPM0, but 
> after "Uncompressing Kernel Image ... OK" there is no more output and no 
> further activity on ethernet (it should boot from nfs-root) or any other 
> device.
> 
> After "cg-seek DENX-v2.6.15; make clean uImage", it works again (everything 
> seems fine, system boots).
> 
> Our board is based on a MPC852T and until now we used "MPC86X" as the 
> BOARD_CHIP_NAME and it worked just fine with 2.6.14 and 2.6.15, but not with 
> 2.6.16 as described above.
> 
> When doing "cg-diff" and carfully examining it's output, I can only see our 
> board-support stuff (not very much, not very special) and some custom drivers 
> that are disabled anyway.
> 
> Any clue about where to start looking?
> 
> I didn't find any suspicious changes in arch/ppc/mm, arch/ppc/syslib and 
> arch/ppc/kernel. Neither in drivers/serial/cpm_uart.
> 
> Which change from 2.6.15 to 2.6.16 could have broken 8xx support for us?
> 
> Is there perhaps a known issue with 2.6.16 and ppc8xx I am unaware of?

2.6.16 working fine over here... What's your .config?

[root@CAS root]# cat /proc/cpuinfo 
processor       : 0
cpu             : 8xx
clock           : 48MHz
bus clock       : 48MHz
revision        : 0.0 (pvr 0050 0000)
bogomips        : 47.71
[root@CAS root]# uname -a
Linux CAS 2.6.16 #1 Thu Apr 13 11:08:03 PDT 2006 ppc unknown