[PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Rosen Penev]

The Armada 38x and 98DX3236 SoCs use this compatible, either paired
with "ns16550a" (armada-38x.dtsi) or on its own
(armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
binding, so dtbs_check reports:

  serial@12000: failed to match any schema with compatible:
  ['marvell,armada-38x-uart', 'ns16550a']

Add a standalone const entry and a two-string variant paired with
"ns16550a".

Validated with make dt_binding_check (8250.yaml) and dt-validate on
armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
gone.

Assisted-by: opencode:big-pickle
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
index 8c2c177faf89..f71c6afe02f2 100644
--- a/Documentation/devicetree/bindings/serial/8250.yaml
+++ b/Documentation/devicetree/bindings/serial/8250.yaml
@@ -109,6 +109,7 @@ properties:
       - const: aspeed,ast2500-vuart
       - const: intel,xscale-uart
       - const: mrvl,pxa-uart
+      - const: marvell,armada-38x-uart
       - const: nuvoton,wpcm450-uart
       - const: nuvoton,npcm750-uart
       - const: nvidia,tegra20-uart
@@ -119,6 +120,9 @@ properties:
               - exar,xr16l2551
               - exar,xr16l2550
           - const: ns8250
+      - items:
+          - const: marvell,armada-38x-uart
+          - const: ns16550a
       - items:
           - enum:
               - altr,16550-FIFO32
-- 
2.55.0

Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[sashiko-bot]

> The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> with "ns16550a" (armada-38x.dtsi) or on its own
> (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> binding, so dtbs_check reports:
> 
>   serial@12000: failed to match any schema with compatible:
>   ['marvell,armada-38x-uart', 'ns16550a']
> 
> Add a standalone const entry and a two-string variant paired with
> "ns16550a".
> 
> Validated with make dt_binding_check (8250.yaml) and dt-validate on
> armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> gone.
> 
> Assisted-by: opencode:big-pickle
> Signed-off-by: Rosen Penev <rosenp@gmail.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260901004203.49686-1-rosenp@gmail.com?part=1

Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Krzysztof Kozlowski]

On Mon, Aug 31, 2026 at 05:42:03PM -0700, Rosen Penev wrote:
> The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> with "ns16550a" (armada-38x.dtsi) or on its own
> (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> binding, so dtbs_check reports:
> 
>   serial@12000: failed to match any schema with compatible:
>   ['marvell,armada-38x-uart', 'ns16550a']
> 
> Add a standalone const entry and a two-string variant paired with
> "ns16550a".
> 
> Validated with make dt_binding_check (8250.yaml) and dt-validate on
> armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> gone.

Drop last paragraph. If AI tool added it, then NEVER DO THAT. We don't
need to read LLM hallucinations.

Commit msgs do not have obvious build process outputs as confirmation
that you did absolutely basic build process step.

The same you do not say:
1. Code compiles
2. Code passes checkpatch
3. Code passes sparse, smatch etc.

> 
> Assisted-by: opencode:big-pickle
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
> index 8c2c177faf89..f71c6afe02f2 100644
> --- a/Documentation/devicetree/bindings/serial/8250.yaml
> +++ b/Documentation/devicetree/bindings/serial/8250.yaml
> @@ -109,6 +109,7 @@ properties:
>        - const: aspeed,ast2500-vuart
>        - const: intel,xscale-uart
>        - const: mrvl,pxa-uart
> +      - const: marvell,armada-38x-uart

ma < mr, keep list ordered.

>        - const: nuvoton,wpcm450-uart
>        - const: nuvoton,npcm750-uart
>        - const: nvidia,tegra20-uart
> @@ -119,6 +120,9 @@ properties:
>                - exar,xr16l2551
>                - exar,xr16l2550
>            - const: ns8250
> +      - items:
> +          - const: marvell,armada-38x-uart

And what if the DTS is just wrong? So warning about wrong DTS is now
suppressed and made documented ABI change?

Best regards,
Krzysztof

Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Conor Dooley]

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On Mon, Aug 31, 2026 at 05:42:03PM -0700, Rosen Penev wrote:
> The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> with "ns16550a" (armada-38x.dtsi) or on its own
> (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> binding, so dtbs_check reports:
> 
>   serial@12000: failed to match any schema with compatible:
>   ['marvell,armada-38x-uart', 'ns16550a']
> 
> Add a standalone const entry and a two-string variant paired with
> "ns16550a".

Only one of these is correct, add one and fix the users.
Given there's match data, it's probably the standalone one.

pw-bot: changes-requested

Thanks,
Conor.

> 
> Validated with make dt_binding_check (8250.yaml) and dt-validate on
> armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> gone.
> 
> Assisted-by: opencode:big-pickle
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
> index 8c2c177faf89..f71c6afe02f2 100644
> --- a/Documentation/devicetree/bindings/serial/8250.yaml
> +++ b/Documentation/devicetree/bindings/serial/8250.yaml
> @@ -109,6 +109,7 @@ properties:
>        - const: aspeed,ast2500-vuart
>        - const: intel,xscale-uart
>        - const: mrvl,pxa-uart
> +      - const: marvell,armada-38x-uart
>        - const: nuvoton,wpcm450-uart
>        - const: nuvoton,npcm750-uart
>        - const: nvidia,tegra20-uart
> @@ -119,6 +120,9 @@ properties:
>                - exar,xr16l2551
>                - exar,xr16l2550
>            - const: ns8250
> +      - items:
> +          - const: marvell,armada-38x-uart
> +          - const: ns16550a
>        - items:
>            - enum:
>                - altr,16550-FIFO32
> -- 
> 2.55.0
> 

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Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Rosen Penev]

On Tue, Sep 1, 2026 at 10:51 AM Conor Dooley <conor@kernel.org> wrote:
>
> On Mon, Aug 31, 2026 at 05:42:03PM -0700, Rosen Penev wrote:
> > The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> > with "ns16550a" (armada-38x.dtsi) or on its own
> > (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> > binding, so dtbs_check reports:
> >
> >   serial@12000: failed to match any schema with compatible:
> >   ['marvell,armada-38x-uart', 'ns16550a']
> >
> > Add a standalone const entry and a two-string variant paired with
> > "ns16550a".
>
> Only one of these is correct, add one and fix the users.
> Given there's match data, it's probably the standalone one.
Commit 62480772263a adds the second one to support earlycon.
>
> pw-bot: changes-requested
>
> Thanks,
> Conor.
>
> >
> > Validated with make dt_binding_check (8250.yaml) and dt-validate on
> > armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> > gone.
> >
> > Assisted-by: opencode:big-pickle
> > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> > ---
> >  Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
> > index 8c2c177faf89..f71c6afe02f2 100644
> > --- a/Documentation/devicetree/bindings/serial/8250.yaml
> > +++ b/Documentation/devicetree/bindings/serial/8250.yaml
> > @@ -109,6 +109,7 @@ properties:
> >        - const: aspeed,ast2500-vuart
> >        - const: intel,xscale-uart
> >        - const: mrvl,pxa-uart
> > +      - const: marvell,armada-38x-uart
> >        - const: nuvoton,wpcm450-uart
> >        - const: nuvoton,npcm750-uart
> >        - const: nvidia,tegra20-uart
> > @@ -119,6 +120,9 @@ properties:
> >                - exar,xr16l2551
> >                - exar,xr16l2550
> >            - const: ns8250
> > +      - items:
> > +          - const: marvell,armada-38x-uart
> > +          - const: ns16550a
> >        - items:
> >            - enum:
> >                - altr,16550-FIFO32
> > --
> > 2.55.0
> >

Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Conor Dooley]

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On Wed, Sep 02, 2026 at 02:34:55PM -0700, Rosen Penev wrote:
> On Tue, Sep 1, 2026 at 10:51 AM Conor Dooley <conor@kernel.org> wrote:
> >
> > On Mon, Aug 31, 2026 at 05:42:03PM -0700, Rosen Penev wrote:
> > > The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> > > with "ns16550a" (armada-38x.dtsi) or on its own
> > > (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> > > binding, so dtbs_check reports:
> > >
> > >   serial@12000: failed to match any schema with compatible:
> > >   ['marvell,armada-38x-uart', 'ns16550a']
> > >
> > > Add a standalone const entry and a two-string variant paired with
> > > "ns16550a".
> >
> > Only one of these is correct, add one and fix the users.
> > Given there's match data, it's probably the standalone one.

> Commit 62480772263a adds the second one to support earlycon.

So the one with the ns16550a fallback is the correct one?

> >
> > pw-bot: changes-requested
> >
> > Thanks,
> > Conor.
> >
> > >
> > > Validated with make dt_binding_check (8250.yaml) and dt-validate on
> > > armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> > > gone.
> > >
> > > Assisted-by: opencode:big-pickle
> > > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> > > ---
> > >  Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
> > >  1 file changed, 4 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
> > > index 8c2c177faf89..f71c6afe02f2 100644
> > > --- a/Documentation/devicetree/bindings/serial/8250.yaml
> > > +++ b/Documentation/devicetree/bindings/serial/8250.yaml
> > > @@ -109,6 +109,7 @@ properties:
> > >        - const: aspeed,ast2500-vuart
> > >        - const: intel,xscale-uart
> > >        - const: mrvl,pxa-uart
> > > +      - const: marvell,armada-38x-uart
> > >        - const: nuvoton,wpcm450-uart
> > >        - const: nuvoton,npcm750-uart
> > >        - const: nvidia,tegra20-uart
> > > @@ -119,6 +120,9 @@ properties:
> > >                - exar,xr16l2551
> > >                - exar,xr16l2550
> > >            - const: ns8250
> > > +      - items:
> > > +          - const: marvell,armada-38x-uart
> > > +          - const: ns16550a
> > >        - items:
> > >            - enum:
> > >                - altr,16550-FIFO32
> > > --
> > > 2.55.0
> > >

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Re: [PATCH] dt-bindings: serial: 8250: add marvell,armada-38x-uart compatible

[Rosen Penev]

On Thu, Sep 3, 2026 at 8:42 AM Conor Dooley <conor@kernel.org> wrote:
>
> On Wed, Sep 02, 2026 at 02:34:55PM -0700, Rosen Penev wrote:
> > On Tue, Sep 1, 2026 at 10:51 AM Conor Dooley <conor@kernel.org> wrote:
> > >
> > > On Mon, Aug 31, 2026 at 05:42:03PM -0700, Rosen Penev wrote:
> > > > The Armada 38x and 98DX3236 SoCs use this compatible, either paired
> > > > with "ns16550a" (armada-38x.dtsi) or on its own
> > > > (armada-xp-98dx3236.dtsi). Neither form is covered by the 8250
> > > > binding, so dtbs_check reports:
> > > >
> > > >   serial@12000: failed to match any schema with compatible:
> > > >   ['marvell,armada-38x-uart', 'ns16550a']
> > > >
> > > > Add a standalone const entry and a two-string variant paired with
> > > > "ns16550a".
> > >
> > > Only one of these is correct, add one and fix the users.
> > > Given there's match data, it's probably the standalone one.
>
> > Commit 62480772263a adds the second one to support earlycon.
>
> So the one with the ns16550a fallback is the correct one?
Good question. I posted an alternative to this patch here:
https://lore.kernel.org/linux-serial/20260902222555.30C151F000E9@smtp.kernel.org/T/#t

If accepted, it would avoid needing ns16550a in dts, and a v2 of this
patch would be the first hunk + dts fixup.
>
> > >
> > > pw-bot: changes-requested
> > >
> > > Thanks,
> > > Conor.
> > >
> > > >
> > > > Validated with make dt_binding_check (8250.yaml) and dt-validate on
> > > > armada-38x and armada-xp 98DX3236 boards: the UART schema errors are
> > > > gone.
> > > >
> > > > Assisted-by: opencode:big-pickle
> > > > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> > > > ---
> > > >  Documentation/devicetree/bindings/serial/8250.yaml | 4 ++++
> > > >  1 file changed, 4 insertions(+)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/serial/8250.yaml b/Documentation/devicetree/bindings/serial/8250.yaml
> > > > index 8c2c177faf89..f71c6afe02f2 100644
> > > > --- a/Documentation/devicetree/bindings/serial/8250.yaml
> > > > +++ b/Documentation/devicetree/bindings/serial/8250.yaml
> > > > @@ -109,6 +109,7 @@ properties:
> > > >        - const: aspeed,ast2500-vuart
> > > >        - const: intel,xscale-uart
> > > >        - const: mrvl,pxa-uart
> > > > +      - const: marvell,armada-38x-uart
> > > >        - const: nuvoton,wpcm450-uart
> > > >        - const: nuvoton,npcm750-uart
> > > >        - const: nvidia,tegra20-uart
> > > > @@ -119,6 +120,9 @@ properties:
> > > >                - exar,xr16l2551
> > > >                - exar,xr16l2550
> > > >            - const: ns8250
> > > > +      - items:
> > > > +          - const: marvell,armada-38x-uart
> > > > +          - const: ns16550a
> > > >        - items:
> > > >            - enum:
> > > >                - altr,16550-FIFO32
> > > > --
> > > > 2.55.0
> > > >