Subject: Re: [PATCH v13 1/2] dt-bindings: clock: add loongson-2 boot clock
 index
To:     Krzysztof Kozlowski <krzysztof.kozlowski@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>,
        linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org,
        devicetree@vger.kernel.org
Cc:     Jianmin Lv <lvjianmin@loongson.cn>,
        Liu Peibao <liupeibao@loongson.cn>, wanghongliang@loongson.cn,
        loongson-kernel@lists.loongnix.cn, zhuyinbo@loongson.cn
References: <20230307115022.12846-1-zhuyinbo@loongson.cn>
 <692a62da-a9a1-fa23-6e24-723d73c3a423@linaro.org>
 <5e9b3bd5-d885-6237-5e14-2becb3c956cc@loongson.cn>
 <31e2a67a-c046-9501-80de-e754ed450195@linaro.org>
 <ace5159b-ebbd-7805-518c-ed3d39e4793e@loongson.cn>
 <b2f9cd15-b303-882a-d4e0-36d1f6d155a8@linaro.org>
 <eca81d44-2513-8002-980d-755af32f36c4@loongson.cn>
 <882bd054-9c3e-1b26-72a5-89ad92e21a79@linaro.org>
 <817a65e9-b605-4bc0-2ff5-fc7f5db8585c@loongson.cn>
 <38b0c1f2-fb0e-722b-19f5-c94796ce0185@linaro.org>
From:   zhuyinbo <zhuyinbo@loongson.cn>
Message-ID: <97d4fe6f-d8fc-4ef3-c974-cc0c6f3d389b@loongson.cn>
Date:   Fri, 10 Mar 2023 10:07:03 +0800
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在 2023/3/10 上午12:12, Krzysztof Kozlowski 写道:
> On 09/03/2023 13:44, zhuyinbo wrote:
>> 在 2023/3/9 下午2:25, Krzysztof Kozlowski 写道:
>>> On 09/03/2023 02:43, zhuyinbo wrote:
>>>> 在 2023/3/8 下午6:38, Krzysztof Kozlowski 写道:
>>>>> On 08/03/2023 10:24, zhuyinbo wrote:
>>>>>>>>> That's an ABI break and commit msg does not explain it.
>>>>>>>> you meaning is that need add a explanation in commit msg that why
>>>>>>> You need good explanation to break the ABI. I don't understand the
>>>>>>> commit msg, but anyway I could not find there justification for ABI
>>>>>>> break. If you do not have good justification, don't break the ABI,
>>>>>> The commit msg is the patch commit  log,  and I maybe not got it about
>>>>>> break the ABI.  You said about "break the ABI"
>>>>>>
>>>>>> is whether is location issue about "LOONGSON2_BOOT_CLK"?   if yes,   the
>>>>>> LOONGSON2_BOOT_CLK was placed
>>>>>>
>>>>>> after LOONGSON2_PIX1_PLL that is due to their clock parent is same.
>>>>>> and I whether need add this explanation
>>>>>>
>>>>>> in patch commit log description?
>>>>> Unfortunately I do not understand single thing from this.
>>>>>
>>>>> Best regards,
>>>>> Krzysztof
>>>> The patch commit log description is patch desription.  as follows:
>>>>
>>>>
>>>> commit 592bc2b4106d787ea166ba16bfde6b3101ab1a8a
>>>> Author: Yinbo Zhu <zhuyinbo@loongson.cn>
>>>> Date:   Tue Mar 7 17:18:32 2023 +0800
>>>>
>>>>        dt-bindings: clock: add loongson-2 boot clock index
>>>>
>>>>        The Loongson-2 boot clock was used to spi and lio peripheral and
>>>>        this patch was to add boot clock index number.
>>> I cannot understand this either.
>> I will rework commit msg .
>>>> and your advice is "That's an ABI break and commit msg does not explain it."
>>>>
>>>> I got it  from your advice that was to add a explanation about
>>>> LOONGSON2_BOOT_CLK's
>>>>
>>>> location issue in patch description, right?
>>> ABI break needs justification, why do you think it is fine or who
>>> is/isn't affected etc. Your commit msg does not explain why ABI break is
>>> okay. It doesn't even explain to me why you need it.
>>    #define LOONGSON2_DC_PLL                               3
>>    #define LOONGSON2_PIX0_PLL                             4
>>    #define LOONGSON2_PIX1_PLL                             5
>> -#define LOONGSON2_NODE_CLK                             6
>> -#define LOONGSON2_HDA_CLK                              7
>> -#define LOONGSON2_GPU_CLK                              8
>> -#define LOONGSON2_DDR_CLK                              9
>> -#define LOONGSON2_GMAC_CLK                             10
>> -#define LOONGSON2_DC_CLK                               11
>> -#define LOONGSON2_APB_CLK                              12
>> -#define LOONGSON2_USB_CLK                              13
>> -#define LOONGSON2_SATA_CLK                             14
>> -#define LOONGSON2_PIX0_CLK                             15
>> -#define LOONGSON2_PIX1_CLK                             16
>> -#define LOONGSON2_CLK_END                              17
>> +#define LOONGSON2_BOOT_CLK                             6
>> +#define LOONGSON2_NODE_CLK                             7
>>
>> after add my patch, if dts still use above macro and not cause any
>> issue. but
>>
>> if dts not use macro rather than use original clk number index that will
>> cause a uncorrect clk,
>>
>> eg.
>>
>> -#define LOONGSON2_NODE_CLK                             6
>>
>> +#define LOONGSON2_NODE_CLK                             7
>>
>>    this issue is that what you said about  "ABI break",  isn't it ?
>>
>>
>> About your advice and question and I will use following description as
>> patch  commit msg,  what do you think?
>>
>>
>> dt-bindings: clock: add loongson-2 boot clock index
>>
>> The spi need to use boot clock and this patch is to add a boot clock
>> index about  LOONGSON2_BOOT_CLK
>>
>> and the LOONGSON2_BOOT_CLK was placed in after LOONGSON2_PIX1_PLL that
>> due to
>>
>> LOONGSON2_PIX1_PLL,  LOONGSON2_PIX0_PLL , LOONGSON2_DC_PLL and
>> LOONGSON2_BOOT_CLK
>>
>> has same parent clock.  In addition, the Loongson  code of the community
>> is still in the development stage,
>>
>> so this patch modification will  not cause uncorrect clk quote issue at
>> present.
> So the reason is same parent clock...? That's not much. These are IDs
> and parent clock do not matter. Drop the ID change.

okay,  I will add this marcro  LOONGSON2_BOOT_CLK in ending.


Thanks.

>
> Best regards,
> Krzysztof