[PATCH v3 3/5] clk: add support for clocks provided by SCP(System Control Processor)

Sudeep Holla sudeep.holla at arm.com
Fri Jun 5 10:10:13 PDT 2015



On 05/06/15 10:36, Sudeep Holla wrote:
>
>
> On 04/06/15 21:20, Stephen Boyd wrote:
>> On 05/27, Sudeep Holla wrote:

[...]

>>> +
>>> +static unsigned long scpi_clk_recalc_rate(struct clk_hw *hw,
>>> +					  unsigned long parent_rate)
>>> +{
>>> +	struct scpi_clk *clk = to_scpi_clk(hw);
>>> +
>>> +	return scpi_ops->clk_get_val(clk->id);
>>> +}
>>> +
>>> +static long scpi_clk_round_rate(struct clk_hw *hw, unsigned long rate,
>>> +				unsigned long *parent_rate)
>>> +{
>>> +	struct scpi_clk *clk = to_scpi_clk(hw);
>>> +
>>> +	if (WARN_ON(clk->rate_min && rate < clk->rate_min))
>>> +		rate = clk->rate_min;
>>> +	if (WARN_ON(clk->rate_max && rate > clk->rate_max))
>>> +		rate = clk->rate_max;
>>> +
>>> +	return rate;
>>> +}
>>
>> Hm.. this seems really generic. It might be better to support a
>> way to tell the framework to limit the min/max rate that's
>> accepted for a clk. That could be done later though.
>>
>
> True, framework have some boundary checks in place. I will check if
> I can use it with minimum changes to the core. If not, we can take this
> up later as you suggested.
>

I found that the framework already provides clk_set_rate_range for this
purpose. Sorry for missing this earlier(seems like that's added quite
recently in v4.0). I think I still need to retain round_rate as the core
framework insists.

Regards,
Sudeep



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