Re: [PATCH v4 09/19] dt-bindings: clock: Add StarFive JH7110 system clock and reset generator

[Hal Feng]

On Wed, 22 Feb 2023 10:40:59 +0000, Conor Dooley wrote:
> On Wed, Feb 22, 2023 at 10:13:19AM +0100, Krzysztof Kozlowski wrote:
>> On 21/02/2023 03:46, Hal Feng wrote:
>> > From: Emil Renner Berthing <kernel@xxxxxxxx>
>> > 
>> > Add bindings for the system clock and reset generator (SYSCRG) on the
>> > JH7110 RISC-V SoC by StarFive Ltd.
>> > 
>> > Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
>> > Signed-off-by: Emil Renner Berthing <kernel@xxxxxxxx>
>> > Signed-off-by: Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
>> 
>> I don't know what is happening here as neither this nor other patchset
>> explains anything. Please stop writing what you do in the patches, but
>> explain why. What is easy to get.
>> 
>> (...)
>> 
>> 
>> > +
>> > +#define JH7110_SYSCLK_PLL0_OUT			190
>> > +#define JH7110_SYSCLK_PLL1_OUT			191
>> > +#define JH7110_SYSCLK_PLL2_OUT			192
>> 
>> NAK. Do not add incorrect bindings just to remove it THE SAME TIME.
> 
> For some context, the PLL driver series [1] does the following, which is
> where this complaint stems from:
>> diff --git a/include/dt-bindings/clock/starfive,jh7110-crg.h b/include/dt-bindings/clock/starfive,jh7110-crg.h
>> index 5e4f21ca0642..086a6ddcf380 100644
>> --- a/include/dt-bindings/clock/starfive,jh7110-crg.h
>> +++ b/include/dt-bindings/clock/starfive,jh7110-crg.h
>> @@ -6,6 +6,12 @@
>>  #ifndef __DT_BINDINGS_CLOCK_STARFIVE_JH7110_CRG_H__
>>  #define __DT_BINDINGS_CLOCK_STARFIVE_JH7110_CRG_H__
>>  
>> +/* PLL clocks */
>> +#define JH7110_CLK_PLL0_OUT			0
>> +#define JH7110_CLK_PLL1_OUT			1
>> +#define JH7110_CLK_PLL2_OUT			2
>> +#define JH7110_PLLCLK_END			3
>> +
>>  /* SYSCRG clocks */
>>  #define JH7110_SYSCLK_CPU_ROOT			0
>>  #define JH7110_SYSCLK_CPU_CORE			1
>> @@ -198,11 +204,7 @@
>>  #define JH7110_SYSCLK_TDM_TDM_INV		188
>>  #define JH7110_SYSCLK_JTAG_CERTIFICATION_TRNG	189
>>  
>> -#define JH7110_SYSCLK_PLL0_OUT			190
>> -#define JH7110_SYSCLK_PLL1_OUT			191
>> -#define JH7110_SYSCLK_PLL2_OUT			192
> 
> I was talking to Emil, who pointed out that these defines aren't
> actually ever used in the dts, so there's nothing really gained
> by adding them here in the first place.
> Seems like this series could simply move these defines into the driver
> (as the PLL addition series also does) and then we would not have to
> be worried about breaking the ABI in the future?

Sorry for that I didn't synchronize this with Xingyu. I'll move these
PLL definitions into the driver in the next version.

Best regards,
Hal

> 
> 1 - https://patchwork.kernel.org/project/linux-riscv/patch/20230221141147.303642-3-xingyu.wu@xxxxxxxxxxxxxxxx/
>