[v2,1/3] dt-bindings: reserved-memory: ramoops: Update the binding

  Update the ramoops region binding document with details
like region can also be reserved dynamically apart from
reserving it statically.

Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
---
Change in v2:
  - Added this patch as per changes going to be done in patch 3/3

 .../bindings/reserved-memory/ramoops.yaml          | 34 ++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)
  

Subject: drop second/last, redundant "binding". The "dt-bindings" prefix
is already stating that these are bindings.

Your subject says nothing. Everything is "update".

On 13/01/2023 12:58, Mukesh Ojha wrote:
> Update the ramoops region binding document with details
> like region can also be reserved dynamically apart from
> reserving it statically.

So what exactly can be here reserved dynamically? And what does it mean
'dynamically'? By whom? How is this property of hardware (not OS)?

> 
> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
> ---
> Change in v2:
>   - Added this patch as per changes going to be done in patch 3/3
> 
>  .../bindings/reserved-memory/ramoops.yaml          | 34 ++++++++++++++++++++--
>  1 file changed, 32 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
> index 0391871..54e46e8 100644
> --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
> +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
> @@ -10,7 +10,8 @@ description: |
>    ramoops provides persistent RAM storage for oops and panics, so they can be
>    recovered after a reboot. This is a child-node of "/reserved-memory", and
>    is named "ramoops" after the backend, rather than "pstore" which is the
> -  subsystem.
> +  subsystem. This region can be reserved both statically or dynamically by
> +  using appropriate property in device tree.
>  
>    Parts of this storage may be set aside for other persistent log buffers, such
>    as kernel log messages, or for optional ECC error-correction data.  The total
> @@ -112,7 +113,13 @@ unevaluatedProperties: false
>  
>  required:
>    - compatible
> -  - reg
> +
> +oneOf:
> +  - required:
> +      - reg
> +
> +  - required:
> +      - size

There is no such property. You cannot require it.

>  
>  anyOf:
>    - required: [record-size]
> @@ -142,3 +149,26 @@ examples:
>              };
>          };
>      };
> +
> +  - |
> +    / {
> +        compatible = "foo";
> +        model = "foo";
> +        #address-cells = <2>;
> +        #size-cells = <2>;
> +
> +        reserved-memory {
> +            #address-cells = <2>;
> +            #size-cells = <2>;
> +            ranges;
> +
> +            ramoops: ramoops_region {

Node names should be generic, no underscores in node names.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

Any reason in naming it differently then existing one? You have there
example.

> +                compatible = "ramoops";
> +                alloc-ranges = <0x0 0x00000000 0xffffffff 0xffffffff>;
> +                size = <0x0 0x10000>;       /* 64kB */
> +                console-size = <0x8000>;    /* 32kB */
> +                record-size = <0x400>;      /*  1kB */
> +                ecc-size = <16>;
> +            };
> +        };
> +    };

Best regards,
Krzysztof
  

Hi Krzysztof,

On 1/13/2023 5:34 PM, Krzysztof Kozlowski wrote:
> Subject: drop second/last, redundant "binding". The "dt-bindings" prefix
> is already stating that these are bindings.
> 
> Your subject says nothing. Everything is "update".
> 

I will fix this.

> On 13/01/2023 12:58, Mukesh Ojha wrote:
>> Update the ramoops region binding document with details
>> like region can also be reserved dynamically apart from
>> reserving it statically.
>  > So what exactly can be here reserved dynamically? And what does it mean
> 'dynamically'? By whom? How is this property of hardware (not OS)?
> 
Normally, for ramoops, already known physical address range from DDR are 
mentioned in Device tree which gets reserved from reserved-memory kernel 
framework(example 1 in this file).

By being dynamic, I meant, with this we are letting the framework to get 
the size from a range of allowable address (<0x0 0x00000000 0xffffffff 
0xffffffff>).

Let me know, if you need more detail.

>>
>> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
>> ---
>> Change in v2:
>>    - Added this patch as per changes going to be done in patch 3/3
>>
>>   .../bindings/reserved-memory/ramoops.yaml          | 34 ++++++++++++++++++++--
>>   1 file changed, 32 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> index 0391871..54e46e8 100644
>> --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> @@ -10,7 +10,8 @@ description: |
>>     ramoops provides persistent RAM storage for oops and panics, so they can be
>>     recovered after a reboot. This is a child-node of "/reserved-memory", and
>>     is named "ramoops" after the backend, rather than "pstore" which is the
>> -  subsystem.
>> +  subsystem. This region can be reserved both statically or dynamically by
>> +  using appropriate property in device tree.
>>   
>>     Parts of this storage may be set aside for other persistent log buffers, such
>>     as kernel log messages, or for optional ECC error-correction data.  The total
>> @@ -112,7 +113,13 @@ unevaluatedProperties: false
>>   
>>   required:
>>     - compatible
>> -  - reg
>> +
>> +oneOf:
>> +  - required:
>> +      - reg
>> +
>> +  - required:
>> +      - size
> 
> There is no such property. You cannot require it.

Forgot to mention this.

--- a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
+++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
@@ -37,6 +37,20 @@ properties:
    reg:
      description: region of memory that is preserved between reboots

+  size:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    minItems: 1
+    maxItems: 2
+    description: >
+      Length based on parent's \#size-cells. Size in bytes of memory to
+      reserve.
+
+  alloc-ranges:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description: >
+      Address and Length pairs. Specifies regions of memory that are
+      acceptable to allocate from.
+
    ecc-size:
      $ref: /schemas/types.yaml#/definitions/uint32
      description: enables ECC support and specifies ECC buffer size in 
bytes
@@ -119,6 +133,7 @@ oneOf:
        - reg

    - required:
+      - alloc-ranges
        - size
> 
>>   
>>   anyOf:
>>     - required: [record-size]
>> @@ -142,3 +149,26 @@ examples:
>>               };
>>           };
>>       };
>> +
>> +  - |
>> +    / {
>> +        compatible = "foo";
>> +        model = "foo";
>> +        #address-cells = <2>;
>> +        #size-cells = <2>;
>> +
>> +        reserved-memory {
>> +            #address-cells = <2>;
>> +            #size-cells = <2>;
>> +            ranges;
>> +
>> +            ramoops: ramoops_region {
> 
> Node names should be generic, no underscores in node names.
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
> 

Thanks.

> Any reason in naming it differently then existing one? You have there
> example.

ramoops@bfdf0000 is not valid after dynamic allocation of memory.
Probably, will mention it as

ramoops_region: ramoops { ??

-Mukesh
> 
>> +                compatible = "ramoops";
>> +                alloc-ranges = <0x0 0x00000000 0xffffffff 0xffffffff>;
>> +                size = <0x0 0x10000>;       /* 64kB */
>> +                console-size = <0x8000>;    /* 32kB */
>> +                record-size = <0x400>;      /*  1kB */
>> +                ecc-size = <16>;
>> +            };
>> +        };
>> +    };
> 
> Best regards,
> Krzysztof
>
  

On Fri, 13 Jan 2023 17:28:44 +0530, Mukesh Ojha wrote:
> Update the ramoops region binding document with details
> like region can also be reserved dynamically apart from
> reserving it statically.
> 
> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
> ---
> Change in v2:
>   - Added this patch as per changes going to be done in patch 3/3
> 
>  .../bindings/reserved-memory/ramoops.yaml          | 34 ++++++++++++++++++++--
>  1 file changed, 32 insertions(+), 2 deletions(-)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dts:17.13-40: Warning (reg_format): /reserved-memory/ramoops@bfdf0000:reg: property has invalid length (8 bytes) (#address-cells == 2, #size-cells == 2)
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: Warning (pci_device_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: Warning (pci_device_bus_num): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: Warning (simple_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: Warning (i2c_bus_reg): Failed prerequisite 'reg_format'
Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: Warning (spi_bus_reg): Failed prerequisite 'reg_format'
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/reserved-memory/ramoops.example.dtb: reserved-memory: ramoops@bfdf0000:reg:0: [3219062784, 65536] is too short
	From schema: /usr/local/lib/python3.10/dist-packages/dtschema/schemas/reg.yaml

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/1673611126-13803-1-git-send-email-quic_mojha@quicinc.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.
  

Hi,

On 1/13/2023 5:34 PM, Krzysztof Kozlowski wrote:
> Subject: drop second/last, redundant "binding". The "dt-bindings" prefix
> is already stating that these are bindings.
> 
> Your subject says nothing. Everything is "update".
> 
> On 13/01/2023 12:58, Mukesh Ojha wrote:
>> Update the ramoops region binding document with details
>> like region can also be reserved dynamically apart from
>> reserving it statically.
> 
> So what exactly can be here reserved dynamically? And what does it mean
> 'dynamically'? By whom? How is this property of hardware (not OS)?
> 
>>
>> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
>> ---
>> Change in v2:
>>    - Added this patch as per changes going to be done in patch 3/3
>>
>>   .../bindings/reserved-memory/ramoops.yaml          | 34 ++++++++++++++++++++--
>>   1 file changed, 32 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> index 0391871..54e46e8 100644
>> --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.yaml
>> @@ -10,7 +10,8 @@ description: |
>>     ramoops provides persistent RAM storage for oops and panics, so they can be
>>     recovered after a reboot. This is a child-node of "/reserved-memory", and
>>     is named "ramoops" after the backend, rather than "pstore" which is the
>> -  subsystem.
>> +  subsystem. This region can be reserved both statically or dynamically by
>> +  using appropriate property in device tree.
>>   
>>     Parts of this storage may be set aside for other persistent log buffers, such
>>     as kernel log messages, or for optional ECC error-correction data.  The total
>> @@ -112,7 +113,13 @@ unevaluatedProperties: false
>>   
>>   required:
>>     - compatible
>> -  - reg
>> +
>> +oneOf:
>> +  - required:
>> +      - reg
>> +
>> +  - required:
>> +      - size
> 
> There is no such property. You cannot require it.

I was thinking, since this size is part reserved-memory.yaml and
we have

allOf:
   - $ref: "reserved-memory.yaml"

Is your comment still applies?

-Mukesh
> 
>>   
>>   anyOf:
>>     - required: [record-size]
>> @@ -142,3 +149,26 @@ examples:
>>               };
>>           };
>>       };
>> +
>> +  - |
>> +    / {
>> +        compatible = "foo";
>> +        model = "foo";
>> +        #address-cells = <2>;
>> +        #size-cells = <2>;
>> +
>> +        reserved-memory {
>> +            #address-cells = <2>;
>> +            #size-cells = <2>;
>> +            ranges;
>> +
>> +            ramoops: ramoops_region {
> 
> Node names should be generic, no underscores in node names.
> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
> 
> Any reason in naming it differently then existing one? You have there
> example.
> 
>> +                compatible = "ramoops";
>> +                alloc-ranges = <0x0 0x00000000 0xffffffff 0xffffffff>;
>> +                size = <0x0 0x10000>;       /* 64kB */
>> +                console-size = <0x8000>;    /* 32kB */
>> +                record-size = <0x400>;      /*  1kB */
>> +                ecc-size = <16>;
>> +            };
>> +        };
>> +    };
> 
> Best regards,
> Krzysztof
>
  

On 27/01/2023 13:29, Mukesh Ojha wrote:
>>> +oneOf:
>>> +  - required:
>>> +      - reg
>>> +
>>> +  - required:
>>> +      - size
>>
>> There is no such property. You cannot require it.
> 
> I was thinking, since this size is part reserved-memory.yaml and
> we have
> 
> allOf:
>    - $ref: "reserved-memory.yaml"
> 
> Is your comment still applies?

Ah, you are right. It's ok.


Best regards,
Krzysztof