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Re: [RFC 06/12] Clk: qcom: support for dynamic updating the PLL

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On 2017-07-29 00:04, Stephen Boyd wrote:
> On 07/27, Abhishek Sahu wrote:
>> Some of the Alpha PLL’s support dynamic update in which the
>> frequency can be changed dynamically without turning off the PLL.
>> 
>> This dynamic update requires the following sequence
>> 
>> 1. Write the desired values to pll_l_val and pll_alpha_val.
>> 2. Toggle pll_latch_input from low to high.
>> 3. Wait for pll_ack_latch to transition from low to high.
>>    The new L and alpha values have been latched. It make
>>    take some time for the PLL to fully settle with these
>>    new values.
>> 4. Pull pll_latch_input low.
>> 
>> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> 
> I think Rajendra has a similar patch that was sent. Is this the
> same? Can you please look on the list and find it and compare?

  Checked the list. Rajendra has two patches

  1. https://www.spinics.net/lists/linux-arm-msm/msg23349.html

  Yes my patch does the same thing with minor diffs.
  My patch checks PLL_UPDATE_BYPASS and handles both
  the cases. We can merge both the patches. I will check
  with Rajendra and will work on this merge.

  2. Following patch fixes different issue although flag name
     is common.

  https://patchwork.kernel.org/patch/9662917/

  Shall I include this patch in my patch series but not
  sure we can directly turn off the PLL inside the PLL
  set rate operation since it will turn the PLL off for
  all its users.

-- 
Abhishek Sahu

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[RFC 00/12] Misc patches for QCOM clocks Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 12/12] clk: qcom: add parent map for regmap mux Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 06/12] Clk: qcom: support for dynamic updating the PLL Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
    Re: [RFC 06/12] Clk: qcom: support for dynamic updating the PLL Stephen Boyd <sboyd@codeaurora.org> - 2017-07-28 20:40 +0200
      Re: [RFC 06/12] Clk: qcom: support for dynamic updating the PLL Abhishek Sahu <absahu@codeaurora.org> - 2017-07-30 16:00 +0200
        Re: [RFC 06/12] Clk: qcom: support for dynamic updating the PLL Stephen Boyd <sboyd@codeaurora.org> - 2017-08-01 23:20 +0200
          Re: [RFC 06/12] Clk: qcom: support for dynamic updating the PLL Abhishek Sahu <absahu@codeaurora.org> - 2017-08-02 16:00 +0200
  [RFC 11/12] clk: qcom: add read-only alpha pll post divider operations Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 10/12] clk: qcom: add read-only divider operations Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 07/12] clk: qcom: add flag for VCO operation Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 08/12] clk: qcom: support for Huayra PLL Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 05/12] clk: qcom: fix 16 bit alpha support calculation Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  [RFC 09/12] clk: qcom: support for Brammo PLL Abhishek Sahu <absahu@codeaurora.org> - 2017-07-27 13:20 +0200
  Re: [RFC 00/12] Misc patches for QCOM clocks Stephen Boyd <sboyd@codeaurora.org> - 2017-07-27 20:40 +0200

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