[PATCH v2 1/2] dt-bindings: mtd: partitions: Add binding for Sercomm parser

[Mikhail Zhilkin <csharper2005@gmail.com>]

On 4/29/2022 11:22 PM, Krzysztof Kozlowski wrote:

>>>> Real dts:
>>>>
>>>> Link:
>>>> https://github.com/openwrt/openwrt/blob/edcc1a9a734bb3fcdc9242025290d3f173e71b78/target/linux/ramips/dts/mt7621_beeline_smartbox-giga.dts#L79
>>>>
>>>> So, I currently found another solution - to extend fixed-partitions.yaml
>>>> with "sercomm,sc-partitions". Is It ok from your side? Can I use this
>>>> code in v3?
>>> Not really, I don't understand why do you need it 
>> The main idea is keeping original Sercomm firmware behavior:
>>
>> 1. If dynamic partition map found then use offsets and mtd sizes stored
>> in partition map. It's provided by "sercomm,sc-partitions" compatible.
>>
>> 2. If dynamic partition map doesn't exist or broken then default values
>> (from dts) are used. It's provided by "fixed-partitions" compatible.
> Then you need to adjust fixed-partitions for such case. See syscon case
> (all over the tree and Documentation/devicetree/bindings/mfd/syscon.yaml).

Thanks! Here's what I got (neither errors nor warnings). I also updated
the parser itself by adding the vendor prefix and tested on a real device. 

 .../mtd/partitions/fixed-partitions.yaml      | 61 ++++++++++++++++++-
 1 file changed, 59 insertions(+), 2 deletions(-)

diff --git
a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
index ea4cace6a955..fa457d55559b 100644
--- a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
+++ b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
@@ -17,9 +17,29 @@ description: |
 maintainers:
   - Rafał Miłecki <rafal@milecki.pl>
 
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - fixed-partitions
+
+  required:
+    - compatible
+
 properties:
   compatible:
-    const: fixed-partitions
+    anyOf:
+      - items:
+          - enum:
+              - sercomm,sc-partitions
+
+          - const: fixed-partitions
+
+      - contains:
+          const: fixed-partitions
+        minItems: 1
+        maxItems: 2
 
   "#address-cells": true
 
@@ -27,7 +47,18 @@ properties:
 
 patternProperties:
   "@[0-9a-f]+$":
-    $ref: "partition.yaml#"
+    allOf:
+      - $ref: "partition.yaml#"
+      - if:
+          properties:
+            compatible:
+              contains:
+                const: sercomm,sc-partitions
+        then:
+          properties:
+            sercomm,scpart-id:
+              description: Partition id in Sercomm partition map
+              $ref: /schemas/types.yaml#/definitions/uint32
 
 required:
   - "#address-cells"
@@ -119,3 +150,29 @@ examples:
             };
         };
     };
+  - |
+    partitions {
+        compatible = "sercomm,sc-partitions", "fixed-partitions";
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        partition@0 {
+            label = "u-boot";
+            reg = <0x0 0x100000>;
+            sercomm,scpart-id=<0>;
+            read-only;
+        };
+
+        partition@100000 {
+            label = "dynamic partition map";
+            reg = <0x100000 0x100000>;
+            sercomm,scpart-id = <1>;
+        };
+
+        partition@200000 {
+            label = "Factory";
+            reg = <0x200000 0x100000>;
+            sercomm,scpart-id = <2>;
+            read-only;
+        };
+    };
-- 
2.25.1


>>> and it does not
>>> include our previous talks.
>> At the time, I didn't realize how important is it. Understanding began
>> to come after dozens of experiments and checking the similar Linux patches.
>>
>>>> diff --git
>>>> a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>>>> b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>>>> index ea4cace6a955..9eebe39a57fb 100644
>>>> --- a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>>>> +++ b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml
>>>> @@ -19,7 +19,11 @@ maintainers:
>>>>  
>>>>  properties:
>>>>    compatible:
>>>> -    const: fixed-partitions
>>>> +    oneOf:
>>>> +      - const: fixed-partitions
>>>> +      - items:
>>>> +          - const: sercomm,sc-partitions
>>>> +          - const: fixed-partitions
>>>>  
>>>>    "#address-cells": true
>>>>  
>>>> @@ -27,7 +31,18 @@ properties:
>>>>  
>>>>  patternProperties:
>>>>    "@[0-9a-f]+$":
>>>> -    $ref: "partition.yaml#"
>>>> +    allOf:
>>>> +      - $ref: "partition.yaml#"
>>>> +      - if:
>>>> +          properties:
>>>> +            compatible:
>>>> +              contains:
>>>> +                const: sercomm,sc-partitions
>>>> +        then:
>>>> +          properties:
>>>> +            scpart-id:
>>> It still misses vendor prefix and we agreed you don't need it, didn't we?
>> Do you mean "sercomm" vendor prefix? If so then we agreed that I include
>> it in a separate patch:
> There was some misunderstanding then. We talk here about scpart-id name.
> Adding vendor prefix cannot be a separate patch because it does not make
> much sense. You add new property with wrong name and immediately
> change/fix it in next patch.
>
> No, it should have proper name since beginning. The property is not used
> in the kernel.

Eureka! Thank you for your patience. I've never seen vendor prefixes for
properties  and didn't know that it's possible too.

>> Link:
>> https://lore.kernel.org/linux-mtd/1b391399-984b-7a63-3265-62ef09caec39@gmail.com/
>>
>> I'm going to send it in v3:
>>
>> ---
>> dt-bindings: Add Sercomm (Suzhou) Corporation vendor prefix
>>
>> Update Documentation/devicetree/bindings/vendor-prefixes.yaml to include
>> "sercomm" as a vendor prefix for "Sercomm (Suzhou) Corporation".
>> Company website:
>> Link: https://www.sercomm.com/
>>
>> Signed-off-by: Mikhail Zhilkin <csharper2005@gmail.com>
>> ---
>>  Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml
>> b/Documentation/devicetree/bindings/vendor-prefixes.yaml
>> index 01430973ecec..65ff22364fb3 100644
>> --- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
>> +++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
>> @@ -1082,6 +1082,8 @@ patternProperties:
>>      description: Sensirion AG
>>    "^sensortek,.*":
>>      description: Sensortek Technology Corporation
>> +  "^sercomm,.*":
>> +    description: Sercomm (Suzhou) Corporation
> This can be separate patch, but it's separate issue...
>
>
> Best regards,
> Krzysztof

-- 
Best regards,
Mikhail


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