Re: [PATCH v6 5/6] clk: qcom: lpassaudiocc-sc7280: Merge lpasscc into lpass_aon

From: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
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>
Subject: Re: [PATCH v6 5/6] clk: qcom: lpassaudiocc-sc7280: Merge lpasscc into lpass_aon
Date: Tue, 31 Jan 2023 14:59:16 +0530	[thread overview]
Message-ID: <c8d779fe-2508-4aa1-8de9-26d858bc068b@quicinc.com> (raw)
In-Reply-To: <CAE-0n50y4JEQqW2wgS_qoDkdrqP=bzpC6b_LpA6Q9P+jDc00ZQ@mail.gmail.com>

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.
>
> 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.

Yes. It's overlapping with lpass_aon ( <0 0x03380000 0 0x30000>).

CC clocks range is <0 0x03389000 0 0x24>;

>
>> 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.

Hence all I want here is to skip this cc clock probing by keeping some 
check.

If we remove, it may cause ABI break.

>
>> +               if (res) {
>> +                       lpass_audio_cc_sc7280_regmap_config.name = "cc";
>> +                       desc = &lpass_cc_sc7280_desc;