Re: [PATCH 2/6] clk: qcom: msm8996-cpu: Statically define PLL dividers

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 14/07/2022 11:32, Yassine Oudjana wrote:
> 
> On Tue, Jun 21 2022 at 20:02:28 +0300, Dmitry Baryshkov 
> <dmitry.baryshkov@linaro.org> wrote:
>> On Tue, 21 Jun 2022 at 19:07, Yassine Oudjana 
>> <yassine.oudjana@gmail.com> wrote:
>>>
>>>  From: Yassine Oudjana <y.oudjana@protonmail.com>
>>>
>>>  This will allow for adding them to clk_parent_data arrays
>>>  in an upcoming patch.
>>>
>>>  Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
>>>  ---
>>>   drivers/clk/qcom/clk-cpu-8996.c | 66 +++++++++++++++++++++------------
>>>   1 file changed, 42 insertions(+), 24 deletions(-)
>>>
>>>  diff --git a/drivers/clk/qcom/clk-cpu-8996.c 
>>> b/drivers/clk/qcom/clk-cpu-8996.c
>>>  index 5dc68dc3621f..217f9392c23d 100644
>>>  --- a/drivers/clk/qcom/clk-cpu-8996.c
>>>  +++ b/drivers/clk/qcom/clk-cpu-8996.c
>>>  @@ -135,6 +135,34 @@ static struct clk_alpha_pll pwrcl_pll = {
>>>          },
>>>   };
>>>
>>>  +static struct clk_fixed_factor pwrcl_pll_postdiv = {
>>>  +       .mult = 1,
>>>  +       .div = 2,
>>>  +       .hw.init = &(struct clk_init_data){
>>>  +               .name = "pwrcl_pll_postdiv",
>>>  +               .parent_data = &(const struct clk_parent_data){
>>>  +                       .hw = &pwrcl_pll.clkr.hw
>>>  +               },
>>>  +               .num_parents = 1,
>>>  +               .ops = &clk_fixed_factor_ops,
>>>  +               .flags = CLK_SET_RATE_PARENT,
>>>  +       },
>>>  +};
>>>  +
>>>  +static struct clk_fixed_factor perfcl_pll_postdiv = {
>>>  +       .mult = 1,
>>>  +       .div = 2,
>>>  +       .hw.init = &(struct clk_init_data){
>>>  +               .name = "perfcl_pll_postdiv",
>>>  +               .parent_data = &(const struct clk_parent_data){
>>>  +                       .hw = &perfcl_pll.clkr.hw
>>>  +               },
>>>  +               .num_parents = 1,
>>>  +               .ops = &clk_fixed_factor_ops,
>>>  +               .flags = CLK_SET_RATE_PARENT,
>>>  +       },
>>>  +};
>>>  +
>>>   static const struct pll_vco alt_pll_vco_modes[] = {
>>>          VCO(3,  250000000,  500000000),
>>>          VCO(2,  500000000,  750000000),
>>>  @@ -261,7 +289,7 @@ static struct clk_cpu_8996_mux pwrcl_smux = {
>>>                  .name = "pwrcl_smux",
>>>                  .parent_names = (const char *[]){
>>>                          "xo",
>>>  -                       "pwrcl_pll_main",
>>>  +                       "pwrcl_pll_postdiv",
>>>                  },
>>>                  .num_parents = 2,
>>>                  .ops = &clk_cpu_8996_mux_ops,
>>>  @@ -277,7 +305,7 @@ static struct clk_cpu_8996_mux perfcl_smux = {
>>>                  .name = "perfcl_smux",
>>>                  .parent_names = (const char *[]){
>>>                          "xo",
>>>  -                       "perfcl_pll_main",
>>>  +                       "perfcl_pll_postdiv",
>>>                  },
>>>                  .num_parents = 2,
>>>                  .ops = &clk_cpu_8996_mux_ops,
>>>  @@ -354,32 +382,25 @@ static int 
>>> qcom_cpu_clk_msm8996_register_clks(struct device *dev,
>>>   {
>>>          int i, ret;
>>>
>>>  -       perfcl_smux.pll = clk_hw_register_fixed_factor(dev, 
>>> "perfcl_pll_main",
>>>  -                                                      "perfcl_pll",
>>>  - CLK_SET_RATE_PARENT,
>>>  -                                                      1, 2);
>>>  -       if (IS_ERR(perfcl_smux.pll)) {
>>>  -               dev_err(dev, "Failed to initialize perfcl_pll_main\n");
>>>  -               return PTR_ERR(perfcl_smux.pll);
>>>  +       ret = devm_clk_hw_register(dev, &pwrcl_pll_postdiv.hw);
>>
>> No need to. I'd suggest picking up the
>> devm_clk_hw_register_fixed_factor patch from my patchset and using
>> this API.
> 
> I did it this way to be able to define it statically in the
> `parent_data` arrays of the secondary muxes in patch 6/6. How
> would I do it this way? Do I define global `static struct clk_hw *`s
> for the postdivs and use them in the `parent_data` arrays, or
> perhaps un-constify the arrays and insert the returned
> `struct clk_hw *`s into them here? Also can you send a link to
> your patch? or is it already applied?

I have been playing with your patchset. In the end I have dropped the 
idea of using devm_clk_hw_register_fixed_factor() and just used 
devm_clk_hw_register too. So:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

> 
>>
>>>  +       if (ret) {
>>>  +               dev_err(dev, "Failed to register pwrcl_pll_postdiv: 
>>> %d", ret);
>>>  +               return ret;
>>>          }
>>>
>>>  -       pwrcl_smux.pll = clk_hw_register_fixed_factor(dev, 
>>> "pwrcl_pll_main",
>>>  -                                                     "pwrcl_pll",
>>>  - CLK_SET_RATE_PARENT,
>>>  -                                                     1, 2);
>>>  -       if (IS_ERR(pwrcl_smux.pll)) {
>>>  -               dev_err(dev, "Failed to initialize pwrcl_pll_main\n");
>>>  -               clk_hw_unregister(perfcl_smux.pll);
>>>  -               return PTR_ERR(pwrcl_smux.pll);
>>>  +       ret = devm_clk_hw_register(dev, &perfcl_pll_postdiv.hw);
>>>  +       if (ret) {
>>>  +               dev_err(dev, "Failed to register perfcl_pll_postdiv: 
>>> %d", ret);
>>>  +               return ret;
>>>          }
>>>
>>>  +       pwrcl_smux.pll = &pwrcl_pll_postdiv.hw;
>>>  +       perfcl_smux.pll = &perfcl_pll_postdiv.hw;
>>>  +
>>>          for (i = 0; i < ARRAY_SIZE(cpu_msm8996_clks); i++) {
>>>                  ret = devm_clk_register_regmap(dev, 
>>> cpu_msm8996_clks[i]);
>>>  -               if (ret) {
>>>  -                       clk_hw_unregister(perfcl_smux.pll);
>>>  -                       clk_hw_unregister(pwrcl_smux.pll);
>>>  +               if (ret)
>>>                          return ret;
>>>  -               }
>>>          }
>>>
>>>          clk_alpha_pll_configure(&perfcl_pll, regmap, &hfpll_config);
>>>  @@ -409,9 +430,6 @@ static int 
>>> qcom_cpu_clk_msm8996_unregister_clks(void)
>>>          if (ret)
>>>                  return ret;
>>>
>>>  -       clk_hw_unregister(perfcl_smux.pll);
>>>  -       clk_hw_unregister(pwrcl_smux.pll);
>>>  -
>>>          return 0;
>>>   }
>>>
>>>  --
>>>  2.36.1
>>>
>>
>>
>> -- 
>> With best wishes
>> Dmitry
> 
> 


-- 
With best wishes
Dmitry