[v8] Add DDR4 memory-controller bindings and factorise LPDDR and DDR bindings

[PATCH v8 2/7] dt-bindings: memory: introduce DDR4

Posted by Clément Le Goffic 4 months, 1 week ago

From: Clément Le Goffic <clement.legoffic@foss.st.com>

Introduce JEDEC compliant DDR bindings, that use new memory-props binding.

Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
Signed-off-by: Clément Le Goffic <legoffic.clement@gmail.com>
---
 .../memory-controllers/ddr/jedec,ddr4.yaml         | 34 ++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
new file mode 100644
index 000000000000..a2eb6f63c0ce
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,ddr4.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: DDR4 SDRAM compliant to JEDEC JESD79-4D
+
+maintainers:
+  - Krzysztof Kozlowski <krzk@kernel.org>
+
+allOf:
+  - $ref: jedec,sdram-props.yaml#
+
+properties:
+  compatible:
+    items:
+      - pattern: "^ddr4-[0-9a-f]{4},[a-z]{1,20},[0-9a-f]{2}$"
+      - const: jedec,ddr4
+
+required:
+  - compatible
+  - density
+  - io-width
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    ddr {
+        compatible = "ddr4-00ff,azaz,ff", "jedec,ddr4";
+        density = <8192>;
+        io-width = <8>;
+    };

-- 
2.43.0

Re: [PATCH v8 2/7] dt-bindings: memory: introduce DDR4

Posted by Krzysztof Kozlowski 3 months, 2 weeks ago

On 30/09/2025 10:46, Clément Le Goffic wrote:
> From: Clément Le Goffic <clement.legoffic@foss.st.com>
> 
> Introduce JEDEC compliant DDR bindings, that use new memory-props binding.


If there is going to be resend, then please repeat here applicable part
of compatible format, e.g. why it's like that.

> 
> Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
> Signed-off-by: Clément Le Goffic <legoffic.clement@gmail.com>
> ---
>  .../memory-controllers/ddr/jedec,ddr4.yaml         | 34 ++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
> new file mode 100644
> index 000000000000..a2eb6f63c0ce
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
> @@ -0,0 +1,34 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,ddr4.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: DDR4 SDRAM compliant to JEDEC JESD79-4D
> +
> +maintainers:
> +  - Krzysztof Kozlowski <krzk@kernel.org>
> +
> +allOf:
> +  - $ref: jedec,sdram-props.yaml#
> +
> +properties:
> +  compatible:
> +    items:
> +      - pattern: "^ddr4-[0-9a-f]{4},[a-z]{1,20},[0-9a-f]{2}$"

Why double ','? I would imagine last ',' to be '-':
ddrX-YYYY,AAAA...-ZZ

Sorry if we discuss that already, but then please remind me and this
would need addressing in commit msg.

> +      - const: jedec,ddr4


Best regards,
Krzysztof

Re: [PATCH v8 2/7] dt-bindings: memory: introduce DDR4

Posted by Clément Le Goffic 3 months, 2 weeks ago

On 10/23/25 15:21, Krzysztof Kozlowski wrote:
> On 30/09/2025 10:46, Clément Le Goffic wrote:
>> From: Clément Le Goffic <clement.legoffic@foss.st.com>
>>
>> Introduce JEDEC compliant DDR bindings, that use new memory-props binding.
> 
> 
> If there is going to be resend, then please repeat here applicable part
> of compatible format, e.g. why it's like that.

Hi Krzysztof, ok

> 
>>
>> Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
>> Signed-off-by: Clément Le Goffic <legoffic.clement@gmail.com>
>> ---
>>   .../memory-controllers/ddr/jedec,ddr4.yaml         | 34 ++++++++++++++++++++++
>>   1 file changed, 34 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
>> new file mode 100644
>> index 000000000000..a2eb6f63c0ce
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,ddr4.yaml
>> @@ -0,0 +1,34 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,ddr4.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: DDR4 SDRAM compliant to JEDEC JESD79-4D
>> +
>> +maintainers:
>> +  - Krzysztof Kozlowski <krzk@kernel.org>
>> +
>> +allOf:
>> +  - $ref: jedec,sdram-props.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    items:
>> +      - pattern: "^ddr4-[0-9a-f]{4},[a-z]{1,20},[0-9a-f]{2}$"
> 
> Why double ','? I would imagine last ',' to be '-':
> ddrX-YYYY,AAAA...-ZZ
> 
> Sorry if we discuss that already, but then please remind me and this
> would need addressing in commit msg.

I do not see anything against that.
I'll wait Julius's review, if any, and I will send the next version with 
this changes.

> 
>> +      - const: jedec,ddr4
> 
> 
> Best regards,
> Krzysztof