[PATCHv4 04/33] CLK: omap: move part of the machine specific clock header contents to driver

Nishanth Menon nm at ti.com
Thu Aug 1 11:21:34 EDT 2013

On 08/01/2013 10:12 AM, Tero Kristo wrote:
> On 08/01/2013 05:04 PM, Nishanth Menon wrote:
>> On 07/31/2013 04:59 AM, Tero Kristo wrote:
>>> On 07/30/2013 09:22 PM, Nishanth Menon wrote:
>>>> this patch should be 3/33 to allow dpll.c to build.
>>>> On 07/23/2013 02:19 AM, Tero Kristo wrote:
>>>>> Some of the clock.h contents are needed by the new OMAP clock driver,
>>>>> including dpll_data and clk_hw_omap. Thus, move these to the generic
>>>>> omap header file which can be accessed by the driver.
>>>> Looking at the change, I wonder what the rules are for the movement?
>>>> commit message was not clear.
>>> This is kind of a merge of almost everything that is needed by clock
>>> drivers at some point. I can move the changes along to the patches that
>>> actually need the exports for clarity and to keep compilation clean.
>> I think it is better to do in stages (while ensuring compilation is
>> clean) - it is a bit hard to understand need and context of movement
>> when a singular movement is done :(
> Yep, will do the change for this.
>> [..]
>>>>> @@ -356,28 +230,13 @@ unsigned long omap_fixed_divisor_recalc(struct
>>>>> clk_hw *hw,
>>>>>   /* DPLL Type and DCO Selection Flags */
>>>>>   #define DPLL_J_TYPE        0x1
>>>>> -long omap2_dpll_round_rate(struct clk_hw *hw, unsigned long
>>>>> target_rate,
>>>>> -            unsigned long *parent_rate);
>>>>> -unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long
>>>>> parent_rate);
>>>>> -int omap3_noncore_dpll_enable(struct clk_hw *hw);
>>>>> -void omap3_noncore_dpll_disable(struct clk_hw *hw);
>>>>> -int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long
>>>>> rate,
>>>>> -                unsigned long parent_rate);
>>>> Why are these being moved to generic?
>>> These are used from the dpll.c by the ops.
>> The ops should probably move as well from mach-omap2. No reason to keep
>> it around in mach-omap2 then.
> There is reason.... I don't want to move _everything_ from mach-omap2 in
> the first phase. But after initial support is in, yes, they can be moved.

I will re-iterate my suggestion again - DPLL enable/disable stuff is 
going to be a series of steps, which would not change if we do DT or 
non-DT. currently those steps reside inside mach-omap2. having a driver 
call into mach-omap2 is counter-intutive, at least to me. if we want to 
have a cleanup in the future, mach-omap2 should depend on drivers/clk 
rather than the other way around. This is the reason of requesting files 
in drivers/clk to be as isolated as possible - dpll operations (the 
actual steps) of doing dpll configuration does sound isolated enough to 
move into drivers/clk and not have reverse dependencies.

Any reverse dependencies should be clearly mentioned with reasoning why 
it cannot be moved in the respective patches, it was a little hard for 
me to indicate precisely which functions make absolutely no sense and 
which not.

I am not saying this is an easy step to do, but for our future cleanups, 
it does sound reasonable to expect from this series.

Nishanth Menon

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