# Re: \[PATCH v2 1/2\] powerpc/mpic: Add Open-PIC global timer document

- List: linuxppc-dev
- 2 messages, 2 authors
- Page: https://ratatoskr.run/linuxppc-dev/2012/08/8062131/t

## Re: \[PATCH v2 1/2\] powerpc/mpic: Add Open-PIC global timer document

- From: Scott Wood \<hidden\>
- Date: 2012-08-14 21:18:40 
- Message: https://ratatoskr.run/linuxppc-dev/2012/08/8062131.md

```text
On 08/13/2012 09:40 PM, Wang Dongsheng-B40534 wrote:
>>>> +Example 2:
>>>>> +
>>>>> +	timer: timer@010f0 {
>>>>> +		compatible = "open-pic,global-timer";
>>>>> +		device_type = "open-pic";
>>>>> +		reg = <0x010f0 4 0x01100 0x100>;
>>>>> +		interrupts = <0 0 3 0
>>>>> +			      1 0 3 0
>>>>> +			      2 0 3 0
>>>>> +		              3 0 3 0>;
>>>>> +	};
>>>>
>>>> 4-cell interrupt specifiers are specific to Freescale MPICs.  This
>>>> means there's no way to describe the timer interrupt on a non-
>> Freescale openpic.
>>>> Again, I suggest we not bother with this in the absence of an actual
>>>> need to support the timer on non-Freescale openpic in partitioned
>> scenarios.
>>>> The existing openpic node is sufficient to describe the
>>>> hardware in the absence of partitioning.   We could have an
>>>> "openpic-no-timer" property to indicate that we're describing it
>>>> separately, so that the absence of a timer node isn't ambiguous as to
>>>> whether it's an old tree or a partitioned scenario.  An fsl,mpic
>>>> compatible would imply openpic-no-timer.
>>>>
>>>> Note that I believe many of the non-Freescale openpic nodes are going
>>>> to be found on systems with real Open Firmware, so we can't go
>>>> changing the device tree for them.
>>> [Wang Dongsheng] In the Open-PIC specification, there are four timer.
>>> 		interrupts = <0 0 3 0
>>> 			      1 0 3 0
>>> 			      2 0 3 0
>>> 		              3 0 3 0>;
>>>
>>> The "interrupts" just let user know there are four timers. Usage based
>> "interrupts"
>>> binding to change dts.
>>
>> I can't understand the above or how it's a response to what I wrote.
>>
> [Wang Dongsheng] I mean this just to tell how many timers to support in Open-PIC
> specification. If someone needs to write "interrupts" into dts, this must comply
> with the specification of the interrupt to write. this is based on the pic driver
> should be changed in different platforms.

My point (beyond that examples provided should be valid for *some*
system) is there is no valid thing to put in the interrupts property
here when the interrupt controller is not "fsl,mpic", so this doesn't work.

-Scott
```

## RE: \[PATCH v2 1/2\] powerpc/mpic: Add Open-PIC global timer document

- From: Wang Dongsheng-B40534 \<hidden\>
- Date: 2012-08-17 07:15:43 
- Message: https://ratatoskr.run/linuxppc-dev/2012/08/8062282.md

```text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```