Re: [PATCH] arm: dts: socfpga: denali needs nand_x_clk too

From: Masahiro Yamada
Date: Sun Jul 01 2018 - 21:36:19 EST


Hi Dinh,

2018-06-27 23:55 GMT+09:00 Dinh Nguyen <dinguyen@xxxxxxxxxx>:
> Hi Masahiro,
>
> On 06/26/2018 09:52 PM, Masahiro Yamada wrote:
>> 2018-06-27 3:09 GMT+09:00 Miquel Raynal <miquel.raynal@xxxxxxxxxxx>:
>>> Hi Masahiro,
>>>
>>> On Tue, 26 Jun 2018 11:38:21 +0900, Masahiro Yamada
>>> <yamada.masahiro@xxxxxxxxxxxxx> wrote:
>>>
>>>> 2018-06-25 23:55 GMT+09:00 Boris Brezillon <boris.brezillon@xxxxxxxxxxx>:
>>>>> On Mon, 25 Jun 2018 09:50:18 -0500
>>>>> Dinh Nguyen <dinguyen@xxxxxxxxxx> wrote:
>>>>>
>>>>>> On 06/22/2018 10:58 AM, Richard Weinberger wrote:
>>>>>>> Masahiro,
>>>>>>>
>>>>>>> Am Freitag, 22. Juni 2018, 16:37:21 CEST schrieb Masahiro Yamada:
>>>>>>>> Hi Richard,
>>>>>>>>
>>>>>>>>
>>>>>>>> 2018-06-19 21:07 GMT+09:00 Richard Weinberger <richard@xxxxxx>:
>>>>>>>>> The denali NAND flash controller needs at least two clocks to operate,
>>>>>>>>> nand_clk and nand_x_clk.
>>>>>>>>> Since 1bb88666775e ("mtd: nand: denali: handle timing parameters by
>>>>>>>>> setup_data_interface()") nand_x_clk is used to derive timing settings.
>>>>>>>>>
>>>>>>>>> Signed-off-by: Richard Weinberger <richard@xxxxxx>
>>>>>>>>> ---
>>>>>>>>> Strictly speaking denali needs a ecc_clk too, but AFAIK such a clock
>>>>>>>>> is not present on this SoC.
>>>>>>>>> But my SoCFPGA knowledge is very limited.
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> //richard
>>>>>>>>> ---
>>>>>>>>> arch/arm/boot/dts/socfpga.dtsi | 3 ++-
>>>>>>>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>>>>>>>>
>>>>>>>>> diff --git a/arch/arm/boot/dts/socfpga.dtsi b/arch/arm/boot/dts/socfpga.dtsi
>>>>>>>>> index 486d4e7433ed..562f7b375bbd 100644
>>>>>>>>> --- a/arch/arm/boot/dts/socfpga.dtsi
>>>>>>>>> +++ b/arch/arm/boot/dts/socfpga.dtsi
>>>>>>>>> @@ -754,7 +754,8 @@
>>>>>>>>> reg-names = "nand_data", "denali_reg";
>>>>>>>>> interrupts = <0x0 0x90 0x4>;
>>>>>>>>> dma-mask = <0xffffffff>;
>>>>>>>>> - clocks = <&nand_clk>;
>>>>>>>>> + clocks = <&nand_clk>, <&nand_x_clk>;
>>>>>>>>> + clock-names = "nand", "nand_x";
>>>>>>>>
>>>>>>>>
>>>>>>>> IMHO, this should be
>>>>>>>>
>>>>>>>> clocks = <&nand_clk>, <&nand_x_clk>, <&nand_x_clk>;
>>>>>>>> clock-names = "nand", "nand_x", "ecc";
>>>>>>
>>>>>> No, it should be just the nand_x and ecc.
>>>>>>
>>>>>> There's already a patch to use the nand_x_clk and not the nand_clk.
>>>>
>>>>
>>>> Different people try to fix the problem in different ways.
>>>>
>>>> I think it is due to miscommunication across sub-systems.
>>>
>>> Is the series named
>>>
>>> mtd: rawnand: denali: add new clocks and improve
>>> setup_data_interface
>>>
>>> still valid?
>>
>> Yes.
>> I believe V4 is valid.
>>
>>
>> Information for Dinh Nguyen:
>>
>> http://patchwork.ozlabs.org/patch/933507/
>> http://patchwork.ozlabs.org/patch/933487/
>> http://patchwork.ozlabs.org/patch/933494/
>> http://patchwork.ozlabs.org/patch/933506/
>>
>>
>> If he is not convinced, I am open to discussion, though.
>
> I wasn't aware of these patches. This patch is staged to go into
> v4.17-rc3 through the arm-soc:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc.git/commit/arch/arm/boot/dts/socfpga.dtsi?h=fixes&id=4eda9b766b042ea38d84df91581b03f6145a2ab0
>
> I think your patch will handle a case where only 1 clock is passed in,
> so it should be okay right?
>

I should be OK,
but please consider the proper fix for v4.19
as Boris suggested.



--
Best Regards
Masahiro Yamada