Re: [PATCH] clk: imx: imx93: introduce clk_bypassed module parameter

[Ahmad Fatoum]

Hello Peng,

On 04.05.23 11:34, Peng Fan wrote:
 >> -----Original Message-----
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
>> Sent: 2023年5月4日 17:31
>> To: Peng Fan <peng.fan@xxxxxxx>; Greg KH <greg@xxxxxxxxx>; Peng Fan
>> (OSS) <peng.fan@xxxxxxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>;
>> krzysztof.kozlowski+dt@xxxxxxxxxx
>> Cc: abelvesa@xxxxxxxxxx; mturquette@xxxxxxxxxxxx; sboyd@xxxxxxxxxx;
>> shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
>> festevam@xxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; linux-
>> clk@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
>> kernel@xxxxxxxxxxxxxxx
>> Subject: Re: [PATCH] clk: imx: imx93: introduce clk_bypassed module
>> parameter
>>
>> On 04/05/2023 11:17, Peng Fan wrote:
>>> + DT maintainers.
>>>
>>>> Subject: Re: [PATCH] clk: imx: imx93: introduce clk_bypassed module
>>>> parameter
>>>>
>>>> On Thu, May 04, 2023 at 04:55:06PM +0800, Peng Fan (OSS) wrote:
>>>>> From: Peng Fan <peng.fan@xxxxxxx>
>>>>>
>>>>> With the clk names specified in clk_bypassed module parameter, give
>>>>> user an option to bypass the clk from managing them by Linux kernel.
>>>>
>>>> As I said on another email, no, please do not add new module
>>>> parameters for drivers, this is not the 1990s
>>>
>>> ok, but this is for boot, so only DT could be considered.
>>>
>>> But DT is to describe hardware, here I just wanna give user an option
>>> to bypass some clocks. Is it ok to add a DT property saying
>>> "fsl,imx93-bypass-clks = <IMX93_CLK_X>, <IMX93_CLK_Y>" ?
>>>
>>
>> I don't know what it is to "bypass some clocks". This does not look like
>> parameter for system at all.
> 
> Currently the linux clk driver registers all the clocks and manage them.
> But when M33 is running, M33 may not wanna linux to manage
> some clocks M33 is using. So I wanna linux not register those clocks
> that M33 will use.

Describe the M33 in the DT, assign it the clocks it depends on and have
a driver bind to it that just claims the clocks in question to ensure
nothing else messes with it?

Cheers,
Ahmad

> 
> Thanks,
> Peng.
> 
>>
>> Best regards,
>> Krzysztof
> 

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