[PATCH v2 08/11] of: Increase MAX_PHANDLE_ARGS

Suravee Suthikulanit suravee.suthikulpanit at amd.com
Wed Jan 29 12:26:35 EST 2014


On 1/29/2014 11:16 AM, Andreas Herrmann wrote:
> On Wed, Jan 29, 2014 at 11:59:12AM -0500, Suravee Suthikulanit wrote:
>> On 1/29/2014 10:57 AM, Rob Herring wrote:
>>>>> diff --git a/include/linux/of.h b/include/linux/of.h
>>>>>>> index 276c546..24e1b28 100644
>>>>>>> --- a/include/linux/of.h
>>>>>>> +++ b/include/linux/of.h
>>>>>>> @@ -67,7 +67,7 @@ struct device_node {
>>>>>>>    #endif
>>>>>>>    };
>>>>>>>
>>>>>>> -#define MAX_PHANDLE_ARGS 8
>>>>>>> +#define MAX_PHANDLE_ARGS 16
>>>>>
>>>>>
>>>>> Since the MMU-500 specify "Number of SMRs" upto 128 registers, shouldn't
>>>>> this be changed to be able to support 128 StreamIDs as well?  Although I am
>>>>> not sure if this would be too big to have on the stack per Rob's comment in
>>>>> the previous patch set.
>>> Do you actually need 128 now? If not, then we can deal with that when
>>> we get there. There are lots of things in spec's that are not actually
>>> implemented or supported.
>>
>> Actually, we are using 32 on the AMD system. So, do you think we can set
>> this to 32 instead?
>
> I think that's ok.
>
> But are we really talking about number of SMRs or number of StreamIDs
> per master device here? Ie. are you just having 32 SMRs for an SMMU on
> your AMD system or do you have master devices which have 32 StreamIDs?
>
> If it's just number of SMRs we don't need to modify this macro.
>
>
> Andreas
>

I am referring to the case where each mmu-master can have upto 32 streamID.

Suravee




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