Re: [PATCH v3 09/19] dt-bindings: nvmem: microchip-otpc: Add required clocks

[Claudiu Beznea <claudiu.beznea@tuxon.dev>]

+ Alexander Dahl

On 3/8/26 18:42, Claudiu Beznea wrote:
> Hi, Alexander,
> 
> On 2/20/26 11:58, Alexander Dahl wrote:
>> Hello Claudiu,
>>
>> Am Sat, Jan 31, 2026 at 05:47:05PM +0200 schrieb Claudiu Beznea:
>>>
>>>
>>> On 1/20/26 17:44, Alexander Dahl wrote:
>>>> The OTPC requires both the peripheral clock through PMC and the main RC
>>>> oscillator.  Seemed to work without explicitly enabling those clocks on
>>>> sama7g5 before, but did not on sam9x60.
>>>>
>>>> Older datasheets were not clear and explicit about this, but recent are,
>>>> e.g. SAMA7G5 series datasheet (DS60001765B),
>>>> section 30.4.1 Power Management:
>>>>
>>>>> The OTPC is clocked through the Power Management Controller (PMC).
>>>>> The user must power on the main RC oscillator and enable the
>>>>> peripheral clock of the OTPC prior to reading or writing the OTP
>>>>> memory.
>>>
>>> As this was not mentioned in the previous datasheet versions, the current
>>> driver don't handle those clocks, and it probably worked as the clocks were
>>> enabled by bootloaders, I think the clocks should be marked as required and
>>> this patch to be propagated as a fix along with fixes on driver and device
>>> trees.
>>
>> What do you mean by "clocks should be marked as required"?  Where?
> 
> In the bindings as you found that the IP don't work if the clocks are not enabled?
> 
>> How?  Is something more necessary, than already done here?
> 
> Update the required section in the yaml file with clocks, at least for the 
> sam9x60, as you found it is not working w/o it.
> 
> I presume it has to be done for SAMA7G5 as well (as this is what the newer 
> datasheets states) but that would involve adding required clocks now which were 
> not needed later. I'm not sure what is the procedure here. I'll let DT 
> maintainers comment on this.
> 
> Thank you,
> Claudiu
>