Re: [PATCH v4 13/16] dt-bindings: net: Add DT bindings for DWMAC on NXP S32G/R SoCs

[Krzysztof Kozlowski <krzk@kernel.org>]

On 31/10/2024 15:29, Jan Petrous wrote:
> On Tue, Oct 29, 2024 at 08:12:37AM +0100, Krzysztof Kozlowski wrote:
>> On Mon, Oct 28, 2024 at 09:24:55PM +0100, Jan Petrous (OSS) wrote:
>>> Add basic description for DWMAC ethernet IP on NXP S32G2xx, S32G3xx
>>> and S32R45 automotive series SoCs.
>>>
>>> Signed-off-by: Jan Petrous (OSS) <jan.petrous@oss.nxp.com>
>>> ---
>>>  .../devicetree/bindings/net/nxp,s32-dwmac.yaml     | 98 ++++++++++++++++++++++
>>>  .../devicetree/bindings/net/snps,dwmac.yaml        |  3 +
>>>  2 files changed, 101 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/net/nxp,s32-dwmac.yaml b/Documentation/devicetree/bindings/net/nxp,s32-dwmac.yaml
>>> new file mode 100644
>>> index 000000000000..b11ba3bc4c52
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/net/nxp,s32-dwmac.yaml
>>> @@ -0,0 +1,98 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +# Copyright 2021-2024 NXP
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/net/nxp,s32-dwmac.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: NXP S32G2xx/S32G3xx/S32R45 GMAC ethernet controller
>>> +
>>> +maintainers:
>>> +  - Jan Petrous (OSS) <jan.petrous@oss.nxp.com>
>>> +
>>> +description:
>>> +  This device is a Synopsys DWC IP, integrated on NXP S32G/R SoCs.
>>> +
>>> +properties:
>>> +  compatible:
>>> +    enum:
>>> +      - nxp,s32g2-dwmac
>>> +      - nxp,s32g3-dwmac
>>> +      - nxp,s32r-dwmac
>>
>> Your driver says these are fully compatible, why this is not expressed
>> here?
>>
> 
> They are compatible on current stage of driver implementation, the
> RGMII interface has no any difference. But later there shall be
> added SGMII and this provides some level of difference, at least
> from max-speed POV.
> 
> The S32R allows higher speed (2G5) on SGMII, but S32G2/S32G3 has
> 1G as maximum.

So G2/G3 will work just fine but with lower speeds? That's the meaning
of compatibility.

Best regards,
Krzysztof