[PATCHv4 03/33] CLK: OMAP4: Add DPLL clock support

Tero Kristo t-kristo at ti.com
Thu Aug 1 11:41:26 EDT 2013


On 08/01/2013 06:10 PM, Nishanth Menon wrote:
> On 08/01/2013 03:29 AM, Rajendra Nayak wrote:
>> Tero,
>>
>> On Tuesday 23 July 2013 12:49 PM, Tero Kristo wrote:
>>> +    dd->control_reg = of_iomap(node, 0);
>>> +    dd->idlest_reg = of_iomap(node, 1);
>>> +    dd->autoidle_reg = of_iomap(node, 2);
>>> +    dd->mult_div1_reg = of_iomap(node, 3);
>>> +
>> []...
>>> +    reg = of_iomap(node, 0);
>>
>> Doing an of_iomap() for every single clock register seems like an
>> overkill
>> and might have performance penalties at boot.
>
> the other option might be to use offset and a single allocation - but I
> think Tero should comment if this is possible or if registers on some
> SoCs are strewn all over the place

Well, currently the basic clock nodes also do their individual 
of_iomaps, so doing a tweak only for the OMAP DPLLs is not going to 
change the figure much.

A generic solution is needed but I think this was commented elsewhere by 
Mike to remain as future optimization (can't find the reference to this 
with a quick search though.)

-Tero




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