Re: [PATCH] MIPS: dts: ralink: Add Mediatek MT7628A SoC

[Rob Herring]

On Fri, Aug 18, 2017 at 9:11 AM, Harvey Hunt <Harvey.Hunt@xxxxxxxxxx> wrote:
> Hi Rob,
>
> On 18/08/17 15:04, Rob Herring wrote:
>>
>> On Fri, Aug 18, 2017 at 4:42 AM, Harvey Hunt <Harvey.Hunt@xxxxxxxxxx>
>> wrote:
>>>
>>> Hi Rob,
>>>
>>> Thanks for the review.
>>>
>>>
>>> On 17/08/17 22:34, Rob Herring wrote:
>>>>
>>>>
>>>> On Tue, Aug 15, 2017 at 05:28:50PM +0100, Harvey Hunt wrote:
>>>>>
>>>>>
>>>>> The MT7628A is the successor to the MT7620 and pin compatible with the
>>>>> MT7688A, although the latter supports only a 1T1R antenna rather than
>>>>> a 2T2R antenna.
>>
>>
>> [...]
>>
>>>>> +               uartlite@c00 {
>>>>
>>>>
>>>>
>>>> serial@c00
>>>>
>>>> And so on. IOW, use standard, generic node names as defined in the DT
>>>> spec.
>>>
>>>
>>>
>>>
>>> The clocks for the UARTs are using the device names "uartlite", "uart1"
>>> and
>>> "uart2" (as defined in arch/mips/ralink/mt7620.c).
>>
>>
>> You can't add clocks to the DT? Looks like mt76x8 at least should be
>> pretty easy with some fixed clocks.
>>
>> Depending if backwards compatibility (old dtb working on new kernel)
>> is a concern on these platforms, you could just change all the names
>> both in the kernel and dts.
>
>
> I don't think backwards compatibility will matter - the bootloaders I've
> come across don't ship DTBs with them and I don't think there are any ralink
> devices using the upstream MT7620 DT.
>
> John might have some thoughts on backwards compat though.
>
>>
>>> Changing the name of the DT nodes causes the serial driver to bail as it
>>> can't find the clock for the device.
>>>
>>> arch/mips/boot/dts/ralink/mt7620a.dtsi is already using the uartlite
>>> name,
>>> although it hasn't been documented...
>>
>>
>> Generally the kernel shouldn't care what the names are (though you can
>> match by name, it's not widely used).
>>
>> In any case, I guess fixing this can be done later.
>>
>> Rob
>>
>
> Shall I respin this patch with the earlier nodes (intc etc) renamed and then
> send a patch later to rename the serial ports in the DT and kernel (assuming
> there are no backwards compatibility issues)?

Yes, that sounds find.

Rob