Re: [RFC v2 1/3] PM / QoS: Add PM_QOS_MEMORY_BANDWIDTH class

[Tomeu Vizoso]

On 16 August 2014 08:35, Pavel Machek <pavel@xxxxxx> wrote:
>>
>> @@ -13,6 +14,7 @@ Each parameters have defined units:
>>   * latency: usec
>>   * timeout: usec
>>   * throughput: kbs (kilo bit / sec)
>> + * memory bandwidth: kbs (kilo bit / sec)
>
> Would mega bits per second make sense here?
>
> I suppose some many-core systems would have memory bandwith
> in > 10 terabit/sec, overflowing u32.

Yeah, I was a bit concerned about excessive rounding increasing the
chances of going to a higher frequency step than strictly necessary,
but after thinking a bit more about it, I think it won't be a problem
because it would be a bad idea anyway to only take into account
explicit bandwidth requirements when calculating the optimal memory
bus frequency.

So I agree that a coarser unit such as mbps should be more appropriate here.

> Plus, if driver in 3/3 is just an example, perhaps comment
> should explain that clearly?

Will do.

> Otherwise looks good,
>
> Acked-by: Pavel Machek <pavel@xxxxxx>

Thanks,

Tomeu

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