On 2/12/2016 2:05 AM, Felipe Balbi wrote:
> 
> Hi,
> 
> John Youn <john.y...@synopsys.com> writes:
>> On 2/10/2016 1:07 PM, Felipe Balbi wrote:
>>> John Youn <john.y...@synopsys.com> writes:
>>>>>> Basically assign all the resources in advance.
>>>>>
>>>>> I thought about that, but wouldn't this, essentially, enable all
>>>>> endpoints unconditionally ? This could, potentially, increase power
>>>>> consumption on some systems, right ? This could also cause "spurious"
>>>>> interrupts if a bogus host tries to move data on an endpoint which
>>>>> hasn't been enabled yet.
>>>>
>>>> No, I mean to just assign resources withouth configuring or enabling
>>>> the endpoint. I have tested this approach and it works. But I still
>>>
>>> oh ok. 
>>>
>>>> need to verify that it won't conflict with anything, such as streams.
>>>
>>> yeah, we would probably have an issue with streams. IIRC, we allocate
>>> one transfer resource per stream, right ?
>>
>> Ends up that is not a concern. Streams always use a single resource
>> per endpoint, not stream.
> 
> hey, that's great. So what's the idea ? static resource assignment on
> endpoint initialization ?
> 

Yes that's it. I will go ahead and submit this fix. See the commit
message for details. I verified with engineers and did a round of
testing and so far no problems.

If you prefer to only assign resources as needed, I have a separate
fix that I can submit if you want.

Also, I think we need to handle backporting separately as neither
patch applies cleanly to 4.3.

Regards,
John
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