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Message-ID: <04788b2c-a212-b8a2-1124-d904f2f61f5d@quicinc.com>
Date: Mon, 5 Feb 2024 14:07:48 +0530
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Subject: Re: [PATCH 2/3] clk: qcom: gcc-sm8150: Add gcc_parents_0_ao support
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To: Konrad Dybcio <konrad.dybcio@linaro.org>,
        Bjorn Andersson
	<andersson@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        "Stephen
 Boyd" <sboyd@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        "Krzysztof
 Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley
	<conor+dt@kernel.org>,
        Taniya Das <quic_tdas@quicinc.com>
CC: <linux-arm-msm@vger.kernel.org>, <linux-clk@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        Ajit Pandey
	<quic_ajipan@quicinc.com>,
        Imran Shaik <quic_imrashai@quicinc.com>,
        "Jagadeesh Kona" <quic_jkona@quicinc.com>
References: <20240123-gcc-ao-support-v1-0-6c18d5310874@quicinc.com>
 <20240123-gcc-ao-support-v1-2-6c18d5310874@quicinc.com>
 <d31a52fc-9073-483d-b84b-1f02a5698a89@linaro.org>
 <77903574-696b-90f9-f136-be5c5d219ba1@quicinc.com>
 <5ae84692-b05d-4a43-aabb-4d2e7d9926d5@linaro.org>
From: "Satya Priya Kakitapalli (Temp)" <quic_skakitap@quicinc.com>
In-Reply-To: <5ae84692-b05d-4a43-aabb-4d2e7d9926d5@linaro.org>
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On 1/25/2024 3:25 PM, Konrad Dybcio wrote:
>
>
> On 1/25/24 06:49, Satya Priya Kakitapalli (Temp) wrote:
>>
>> On 1/23/2024 11:17 PM, Konrad Dybcio wrote:
>>>
>>>
>>> On 1/23/24 17:34, Satya Priya Kakitapalli wrote:
>>>> Add active_only support for gcc_parents_0, this is needed because
>>>> some of the clocks under it are critical which would vote on xo
>>>> blocking the suspend.
>>>>
>>>> Signed-off-by: Satya Priya Kakitapalli <quic_skakitap@quicinc.com>
>>>> ---
>>>
>>> Is there a need to keep gcc_cpuss_ahb_clk_src around? Do we do any
>>> ratesetting on it? Should we ever turn it off?
>>>
>>
>> The branch clocks under gcc_cpuss_ahb_clk_src are critical clocks, 
>> which are running at 19.2Mhz causing vote on XO during suspend. As of 
>> now no rate setting is happening but this rcg is useful to get the 
>> exact rates from debugfs. Hence this change is needed to avoid XO 
>> shutdown issues.
>
> So, if I underderstood you correctly, this clock serves no purpose other
> than getting rate?
>
> In this case, I'd say we should de-register it from the clock driver and
> use debugcc [1] (contributions welcome!) for precise measurements.
>

Although currently there is no rate-setting happening now, its better to 
keep the rcg modelling as is, considering that it might be needed if 
some use case arises in future.