On Jul 26, 2011, at 4:23 AM, Wolfgang Denk wrote:
> Dear Kumar Gala,
>
> In message <fc7a4dae-b05c-49f3-9201-1b5bb559f...@kernel.crashing.org> you
> wrote:
>>
>> Do you know if this board has any real reset on a FPGA or CPLD or
>> something like that.
>
> There is no such faeature on that board, nor on any of a number of
> other 85xx boards I have access to.
>
>> The problem on the 8555/8541 is the reset you are trigger is just a core
>> reset and not one of the full SoC. If there is a board level means I
>> would suggest trying to utilize it instead. If not this might be
>> painful & problematic as you'll have to slowly make sure we are
>> 'resetting' each SoC block properly.
>
> Is this also the cause why the Linux reboot ommand does not work?
Probably.
> If so, I wonder what has changed, because this used to be working in
> older versions of the kernel? I did not attampt a full git bisect,
> but from some old images I still found it appears it must have been
> broken between 2.6.16 ("reboot" in Linux works fine) and 2.6.27
> ("reboot" does not work any more) - so probably this was part of the
> arch/ppc => arch/powerpc rework.
Possible, its a pretty fragile reset solution so one (or a thousand) of a
million things could be the issue.
> Is there any specific reason we don't use the good old approach of
> triggering an unhandled machine check exception?
Hmm, when did we do that? I've got no issues with it if it causes HRESET_REQ
to be signaled on the older devices. On MPC8548 and greater we provided a
means for software to causes HRESET_REQ to be asserted. So if an unhandled
mcheck will do this sounds good to me.
- k
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
