[PATCH] powerpc/time: When starting the decrementer don't zero the other bits in TCR

[Kumar Gala]

On Sep 1, 2011, at 10:38 AM, Tudor Laurentiu wrote:

> On 9/1/2011 4:56 PM, Kumar Gala wrote:
>> 
>> On Sep 1, 2011, at 3:31 AM, Tudor Laurentiu wrote:
>> 
>>> On 9/1/2011 9:27 AM, Kumar Gala wrote:
>>>> 
>>>> On Aug 25, 2011, at 7:19 AM, Laurentiu Tudor wrote:
>>>> 
>>>>> Clearing the other TCR bits might break code that sets them (e.g. to setup
>>>>> the watchdog or fixed interval timer) before start_cpu_decrementer() gets
>>>>> called.
>>>> 
>>>> Can you be more specific about the case you're concerned about.  I'm not sure we want to leave the FIT enabled if it was previously.  Watchdog I could possibly see leaving alone.
>>> 
>>> My particular case was this: I was experimenting with having the watchdog enabled during the boot process, in case something goes wrong before the normal watchdog mechanism kicks in. That didn't work without making this modification.
>>> Then, thinking that having a function start_cpu_decrementer() touching the other timers and not only the decrementer as its name implies might not be good. So I submitted this patch to the public mailing list to let the community decide if it's useful.
>> 
>> So I think renaming the function is fine, and I think not touching the watchdog bits is also reasonable.  So if you update the patch along those lines I think we can push in.  I do want to make sure that the FIT is disabled as we dont expect it.
> 
> how about:
> 
> static void setup_cpu_timers()
> 
> ?

Sounds fine to me

> 
>> Probably add a comment about how care needs to be taken if the wathchdog is enable be firmware or a previous kernel.
> 
> OK.
> 
> 
> 
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev at lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev