Document brcm,bmips-cbr-reg property.

Some SoC suffer from a BUG where CBR(Core Base Register)
address might badly/never inizialized by the Bootloader or
reaching it from co-processor registers if the system
boots from secondary CPU results in invalid address.

The CBR address is always the same on the SoC.

Usage of this property is to give an address also in these broken
configuration/bootloader.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 .../devicetree/bindings/mips/brcm/soc.yaml    | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/Documentation/devicetree/bindings/mips/brcm/soc.yaml b/Documentation/devicetree/bindings/mips/brcm/soc.yaml
index 975945ca2888..6b961b62aff2 100644
--- a/Documentation/devicetree/bindings/mips/brcm/soc.yaml
+++ b/Documentation/devicetree/bindings/mips/brcm/soc.yaml
@@ -55,6 +55,16 @@ properties:
          under the "cpus" node.
         $ref: /schemas/types.yaml#/definitions/uint32
 
+      brcm,bmips-cbr-reg:
+        description: Reference address of the CBR.
+          Some SoC suffer from a BUG where CBR(Core Base Register)
+          address might badly/never inizialized by the Bootloader or
+          reaching it from co-processor registers if the system
+          boots from secondary CPU results in invalid address.
+          The CBR address is always the same on the SoC hence it
+          can be provided in DT to handle these broken case.
+        $ref: /schemas/types.yaml#/definitions/uint32
+
     patternProperties:
       "^cpu@[0-9]$":
         type: object
@@ -64,6 +74,20 @@ properties:
     required:
       - mips-hpt-frequency
 
+if:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - brcm,bcm6358
+          - brcm,bcm6368
+
+then:
+  properties:
+    cpus:
+      required:
+        - brcm,bmips-cbr-reg
+
 additionalProperties: true
 
 examples:
-- 
2.43.0

On Thu, May 09, 2024 at 10:47:46PM +0200, Christian Marangi wrote:
> Document brcm,bmips-cbr-reg property.
> 
> Some SoC suffer from a BUG where CBR(Core Base Register)
> address might badly/never inizialized by the Bootloader or
> reaching it from co-processor registers if the system
> boots from secondary CPU results in invalid address.
> 
> The CBR address is always the same on the SoC.
> 
> Usage of this property is to give an address also in these broken
> configuration/bootloader.
> 
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---
>  .../devicetree/bindings/mips/brcm/soc.yaml    | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mips/brcm/soc.yaml b/Documentation/devicetree/bindings/mips/brcm/soc.yaml
> index 975945ca2888..6b961b62aff2 100644
> --- a/Documentation/devicetree/bindings/mips/brcm/soc.yaml
> +++ b/Documentation/devicetree/bindings/mips/brcm/soc.yaml
> @@ -55,6 +55,16 @@ properties:
>           under the "cpus" node.
>          $ref: /schemas/types.yaml#/definitions/uint32
>  
> +      brcm,bmips-cbr-reg:
> +        description: Reference address of the CBR.
> +          Some SoC suffer from a BUG where CBR(Core Base Register)
> +          address might badly/never inizialized by the Bootloader or

"be badly or never initialized"

> +          reaching it from co-processor registers if the system

"reading"?

Otherwise,
Acked-by: Conor Dooley <conor.dooley@microchip.com>

Cheers,
Conor.

> +          boots from secondary CPU results in invalid address.
> +          The CBR address is always the same on the SoC hence it
> +          can be provided in DT to handle these broken case.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +
>      patternProperties:
>        "^cpu@[0-9]$":
>          type: object
> @@ -64,6 +74,20 @@ properties:
>      required:
>        - mips-hpt-frequency
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        enum:
> +          - brcm,bcm6358
> +          - brcm,bcm6368
> +
> +then:
> +  properties:
> +    cpus:
> +      required:
> +        - brcm,bmips-cbr-reg
> +
>  additionalProperties: true
>  
>  examples:
> -- 
> 2.43.0
>