Message-ID: <b1ae5119-423e-1d6a-546a-85b4e212e5f9@quicinc.com>
Date:   Wed, 1 Feb 2023 12:37:13 +0530
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Subject: Re: [PATCH v6 5/6] clk: qcom: lpassaudiocc-sc7280: Merge lpasscc into
 lpass_aon
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To:     Stephen Boyd <swboyd@chromium.org>, <agross@kernel.org>,
        <andersson@kernel.org>, <broonie@kernel.org>,
        <konrad.dybcio@somainline.org>,
        <krzysztof.kozlowski+dt@linaro.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-clk@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <mturquette@baylibre.com>,
        <quic_plai@quicinc.com>, <quic_rohkumar@quicinc.com>,
        <robh+dt@kernel.org>
References: <1674728065-24955-1-git-send-email-quic_srivasam@quicinc.com>
 <1674728065-24955-6-git-send-email-quic_srivasam@quicinc.com>
 <CAE-0n50y4JEQqW2wgS_qoDkdrqP=bzpC6b_LpA6Q9P+jDc00ZQ@mail.gmail.com>
 <c8d779fe-2508-4aa1-8de9-26d858bc068b@quicinc.com>
 <CAE-0n50fJWqHE0A3R8yawGZAcNb_QDNQ5h2=CXxKAX0eOghegQ@mail.gmail.com>
From:   Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
Organization: Qualcomm
In-Reply-To: <CAE-0n50fJWqHE0A3R8yawGZAcNb_QDNQ5h2=CXxKAX0eOghegQ@mail.gmail.com>
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On 2/1/2023 1:56 AM, Stephen Boyd wrote:
Thanks for your time Stephen!!!
> Quoting Srinivasa Rao Mandadapu (2023-01-31 01:29:16)
>> On 1/31/2023 6:34 AM, Stephen Boyd wrote:
>> Thanks for your Time Stephen!!!
>>> Quoting Srinivasa Rao Mandadapu (2023-01-26 02:14:24)
>>>> Merge lpasscc clocks into lpass_aon clk_regmap structure as they
>>>> are using same register space.
>>>> Add conditional check for doing lpasscc clock registration only
>>>> if regname specified in device tree node.
>>>> In existing implementation, lpasscc clocks and lpass_aon clocks are
>>>> being registered exclusively and overlapping if both of them are
>>>> to be used.
>>>> This is required to avoid such overlapping and to register
>>>> lpasscc clocks and lpass_aon clocks simultaneously.
>>> Can you describe the register ranges that are overlapping?
>> Okay. Will add register ranges in description.
> Thanks!
>
>>> Here's what I see in DT right now:
>>>
>>>                   lpasscc: lpasscc@3000000 {
>>>                           compatible = "qcom,sc7280-lpasscc";
>>>                           reg = <0 0x03000000 0 0x40>,
>>>                                 <0 0x03c04000 0 0x4>;
>>>                           ...
>>>                   };
>>>
>>>                   lpass_audiocc: clock-controller@3300000 {
>>>                           compatible = "qcom,sc7280-lpassaudiocc";
>>>                           reg = <0 0x03300000 0 0x30000>,
>>>                                 <0 0x032a9000 0 0x1000>;
>>>                           ...
>>>                   };
>>>
>>>                   lpass_aon: clock-controller@3380000 {
>>>                           compatible = "qcom,sc7280-lpassaoncc";
>>>                           reg = <0 0x03380000 0 0x30000>;
>>>                           ...
>>>                   };
>>>
>>>                   lpass_core: clock-controller@3900000 {
>>>                           compatible = "qcom,sc7280-lpasscorecc";
>>>                           reg = <0 0x03900000 0 0x50000>;
>>>                           ...
>>>                   };
>>>
>>> Presumably lpascc is really supposed to be a node named
>>> 'clock-controller' and is the node that is overlapping with lpass_aon?
>> Okay. As it's been coming previous patches, didn't change the name.
>>
>> May be we need to do it as separate patch.
> Sure, another patch to rename lpasscc to clock-controller would be
> appreciated.
>
>> Yes. It's overlapping with lpass_aon ( <0 0x03380000 0 0x30000>).
>>
>> CC clocks range is <0 0x03389000 0 0x24>;
> Is that a new register range for lpasscc? Why do we have that node at
> all? Can we add different properties to the existing lpass_audiocc,
> lpass_aon, or lpass_core nodes to indicate what clks should or shouldn't
> be registered or provided to the kernel?

It's not new register range. They are actually AHBM and AHBS clock 
registers within lpass_aon regmap range.

Here what I meant lpasscc clocks are not of lpasscc node. I am sorry to 
make you confused.

As the reg-name used as "CC", mentioning it as lpasscc clocks. I will 
rephrase commit message and re-post.

Previously these two clocks are registered separately. Now we are 
merging them into lpass_aon clk reg space.


>
>>>> Fixes: 4ab43d171181 ("clk: qcom: Add lpass clock controller driver for SC7280")
>>>> Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
>>>> Tested-by: Mohammad Rafi Shaik <quic_mohs@quicinc.com>
>>>> ---
>>>>    drivers/clk/qcom/lpassaudiocc-sc7280.c | 13 +++++++++----
>>>>    1 file changed, 9 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/drivers/clk/qcom/lpassaudiocc-sc7280.c b/drivers/clk/qcom/lpassaudiocc-sc7280.c
>>>> index 1339f92..8e2f433 100644
>>>> --- a/drivers/clk/qcom/lpassaudiocc-sc7280.c
>>>> +++ b/drivers/clk/qcom/lpassaudiocc-sc7280.c
>>>> @@ -826,10 +829,12 @@ static int lpass_aon_cc_sc7280_probe(struct platform_device *pdev)
>>>>                   return ret;
>>>>
>>>>           if (of_property_read_bool(pdev->dev.of_node, "qcom,adsp-pil-mode")) {
>>>> -               lpass_audio_cc_sc7280_regmap_config.name = "cc";
>>>> -               desc = &lpass_cc_sc7280_desc;
>>>> -               ret = qcom_cc_probe(pdev, desc);
>>>> -               goto exit;
>>>> +               res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cc");
>>> We shouldn't need to check for reg-name property. Instead, the index
>>> should be the only thing that matters.
>> As qcom_cc_probe() function is mapping the zero index reg property, and
>>
>> in next implementation qcom_cc_really_probe() is also probing zero index
>> reg property,
>>
>> unable to map the same region twice.
> Use qcom_cc_probe_by_index()?

With this, if we mention some index and if it's not present in DT, it 
will return error.

Is it okay if error is ignored and proceed?

>
>> Hence all I want here is to skip this cc clock probing by keeping some
>> check.
>>
>> If we remove, it may cause ABI break.
>>
> I'm not sure what you mean here about ABI break, but hopefully just
> using qcom_cc_probe_by_index() works!