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Message-ID: <2e86be1b-7923-431c-8220-a17af14a457a@quicinc.com>
Date:   Wed, 22 Nov 2023 16:15:24 +0530
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Subject: Re: [PATCH v2 3/9] dt-bindings: clock: ipq5332: drop the few nss
 clocks definition
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To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
CC:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.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>,
        Richard Cochran <richardcochran@gmail.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-clk@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <netdev@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>
References: <20231121-ipq5332-nsscc-v2-0-a7ff61beab72@quicinc.com>
 <20231121-ipq5332-nsscc-v2-3-a7ff61beab72@quicinc.com>
 <43376552-7e79-4f34-94ca-63767a95564b@linaro.org>
 <8bb79735-3b5d-4229-b0f4-bc50d61fdba1@quicinc.com>
 <d26eae8d-4968-4ab0-bd9b-696d7b3865ec@linaro.org>
 <2e357fcf-5348-4fb2-b693-2d6bb4d58b21@quicinc.com>
 <CAA8EJprH5zhSQoTAfQG3nq8Ud=7MVKKhWt0x7SGyFP9JnxWgBA@mail.gmail.com>
From:   Kathiravan Thirumoorthy <quic_kathirav@quicinc.com>
In-Reply-To: <CAA8EJprH5zhSQoTAfQG3nq8Ud=7MVKKhWt0x7SGyFP9JnxWgBA@mail.gmail.com>
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On 11/22/2023 3:53 PM, Dmitry Baryshkov wrote:
> On Wed, 22 Nov 2023 at 12:19, Kathiravan Thirumoorthy
> <quic_kathirav@quicinc.com> wrote:
>>
>>
>>
>> On 11/22/2023 3:42 PM, Krzysztof Kozlowski wrote:
>>> On 22/11/2023 11:08, Kathiravan Thirumoorthy wrote:
>>>>
>>>>
>>>> On 11/21/2023 8:36 PM, Krzysztof Kozlowski wrote:
>>>>> On 21/11/2023 15:30, Kathiravan Thirumoorthy wrote:
>>>>>> In commit 0dd3f263c810 ("clk: qcom: ipq5332: enable few nssnoc clocks in
>>>>>
>>>>> Where is this commit coming from?
>>>>>
>>>>>> driver probe"), gcc_snoc_nssnoc_clk, gcc_snoc_nssnoc_1_clk,
>>>>>> gcc_nssnoc_nsscc_clk are enabled in driver probe to keep it always-on.
>>>>>
>>>>> Implementation can change and for example bring back these clocks. Are
>>>>> you going to change bindings? No, drop the patch.
>>>>>
>>>>> Bindings should be dropped only in a few rare cases like clocks not
>>>>> available for OS or bugs.
>>>>
>>>> Thanks Krzysztof. Will drop this patch in V3.
>>>>
>>>> One more question to understand further. In IPQ SoCs there are bunch of
>>>> coresight / QDSS clocks but coresight framework doesn't handle all
>>>> clocks. Those clocks are enabled in bootloader stage itself. In such
>>>> case, should I drop the clocks from both binding and driver or only from
>>>> driver?
>>>
>>> That's not really the reason to drop them at all. Neither from driver,
>>> nor from bindings. You should not rely on bootloader handling your clocks
>>
>>
>> Thanks, lets say if those clocks are not needed at all by OS since QDSS
>> is not used and needed only for the boot loaders to access the
>> corresponding address space, in such case what can be done? I
>> understand, at first those clocks should not have been added to the driver.
> 
> First, what is QDSS? Yet another acronym?

Qualcomm Debug Sub System - which compromises of various debug infra 
like coresight, DCC and so on.

> 
> Second, if they are not used now, they can get used later.
> 

Thanks. I will drop it from driver and leave the bindings as it is.

Thanks,
Kathiravan