Re: [PATCH 08/13] dt-bindings: serial: fsl-lpuart: add i.MXRT compatible

[Giulio Benetti <giulio.benetti@benettiengineering.com>]

Hello Rob, Jesse, All,

> Il giorno 3 nov 2021, alle ore 01:49, Rob Herring <robh@kernel.org> ha scritto:
> 
> On Mon, Nov 1, 2021 at 6:34 PM Jesse Taube <mr.bossman075@gmail.com> wrote:
>> 
>> 
>> 
>>> On 11/1/21 16:13, Rob Herring wrote:
>>> On Sun, Oct 24, 2021 at 11:40:22AM -0400, Jesse Taube wrote:
>>>> Add i.MXRT documentation for compatible string.
>>>> 
>>>> Cc: Giulio Benetti <giulio.benetti@benettiengineering.com>
>>>> Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>
>>>> ---
>>>> Documentation/devicetree/bindings/serial/fsl-lpuart.yaml | 1 +
>>>> 1 file changed, 1 insertion(+)
>>>> 
>>>> diff --git a/Documentation/devicetree/bindings/serial/fsl-lpuart.yaml b/Documentation/devicetree/bindings/serial/fsl-lpuart.yaml
>>>> index a90c971b4f1f..4b4340def2aa 100644
>>>> --- a/Documentation/devicetree/bindings/serial/fsl-lpuart.yaml
>>>> +++ b/Documentation/devicetree/bindings/serial/fsl-lpuart.yaml
>>>> @@ -21,6 +21,7 @@ properties:
>>>>           - fsl,ls1028a-lpuart
>>>>           - fsl,imx7ulp-lpuart
>>>>           - fsl,imx8qm-lpuart
>>>> +          - fsl,imxrt-lpuart
>>> 
>>> Actually, 'rt' is not a single part is it? If the variations are same
>>> die, but fused off then no need to distinguish. Otherwise, these should
>>> be SoC specific.
>>> 
>> I don't exactly know what "but fused off" means I would assume
>> disconnected but on-die?
> 
> Right. Or not pinned out is another possibility.
> 
>> The imxrtxxx is a series that has the same UART
>> controller across them. Should I add ACK?
> 
> Looking at the errata docs briefly, there's at least 2 die as some of
> the errata docs give the mask id. So they aren't necessarily 'the
> same'.

Thank you for pointing, we’ve missed this particular.

> You want the compatible strings to be specific enough to handle
> any differences or errata. If you only care about the imxrt1050, then
> I'd just use that and move on.

We plan to add from imxrt1020 to imxrt1170 and eventual new SoC, so we definitely need separate
.compatible strings.

@Jesse, can you please update with ‘fsl,imxrt1050”?

> Otherwise, maybe someone from NXP wants
> to comment?

Any NXP comment is welcome!

Best regards
Giulio Benetti
Benetti engineering sas

> 
> Rob