[PATCH v2 net 2/4] dt-bindings: net: Document fsl,erratum-a009885

[PATCH v2 net 2/4] dt-bindings: net: Document fsl,erratum-a009885

[Tobias Waldekranz]

Update FMan binding documentation with the newly added workaround for
erratum A-009885.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
 Documentation/devicetree/bindings/net/fsl-fman.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/fsl-fman.txt b/Documentation/devicetree/bindings/net/fsl-fman.txt
index c00fb0d22c7b..020337f3c05f 100644
--- a/Documentation/devicetree/bindings/net/fsl-fman.txt
+++ b/Documentation/devicetree/bindings/net/fsl-fman.txt
@@ -410,6 +410,15 @@ PROPERTIES
 		The settings and programming routines for internal/external
 		MDIO are different. Must be included for internal MDIO.
 
+- fsl,erratum-a009885
+		Usage: optional
+		Value type: <boolean>
+		Definition: Indicates the presence of the A009885
+		erratum describing that the contents of MDIO_DATA may
+		become corrupt unless it is read within 16 MDC cycles
+		of MDIO_CFG[BSY] being cleared, when performing an
+		MDIO read operation.
+
 - fsl,erratum-a011043
 		Usage: optional
 		Value type: <boolean>
-- 
2.25.1

Re: [PATCH v2 net 2/4] dt-bindings: net: Document fsl,erratum-a009885

[Rob Herring]

On Tue, Jan 18, 2022 at 10:50:51PM +0100, Tobias Waldekranz wrote:
> Update FMan binding documentation with the newly added workaround for
> erratum A-009885.
> 
> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---
>  Documentation/devicetree/bindings/net/fsl-fman.txt | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/fsl-fman.txt b/Documentation/devicetree/bindings/net/fsl-fman.txt
> index c00fb0d22c7b..020337f3c05f 100644
> --- a/Documentation/devicetree/bindings/net/fsl-fman.txt
> +++ b/Documentation/devicetree/bindings/net/fsl-fman.txt
> @@ -410,6 +410,15 @@ PROPERTIES
>  		The settings and programming routines for internal/external
>  		MDIO are different. Must be included for internal MDIO.
>  
> +- fsl,erratum-a009885

Adding errata properties doesn't work because then you have to update 
your dtb to fix the issue where as if you use the compatible property 
(specific to the SoC) you can fix the issue with just a (stable) kernel 
update.

Yes, I see we already have some, but doesn't mean we need more of them.

> +		Usage: optional
> +		Value type: <boolean>
> +		Definition: Indicates the presence of the A009885
> +		erratum describing that the contents of MDIO_DATA may
> +		become corrupt unless it is read within 16 MDC cycles
> +		of MDIO_CFG[BSY] being cleared, when performing an
> +		MDIO read operation.
> +
>  - fsl,erratum-a011043
>  		Usage: optional
>  		Value type: <boolean>
> -- 
> 2.25.1
> 
> 

Re: [PATCH v2 net 2/4] dt-bindings: net: Document fsl,erratum-a009885

[Tobias Waldekranz]

On Thu, Jan 20, 2022 at 20:08, Rob Herring <robh@kernel.org> wrote:
> On Tue, Jan 18, 2022 at 10:50:51PM +0100, Tobias Waldekranz wrote:
>> Update FMan binding documentation with the newly added workaround for
>> erratum A-009885.
>> 
>> Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
>> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
>> ---
>>  Documentation/devicetree/bindings/net/fsl-fman.txt | 9 +++++++++
>>  1 file changed, 9 insertions(+)
>> 
>> diff --git a/Documentation/devicetree/bindings/net/fsl-fman.txt b/Documentation/devicetree/bindings/net/fsl-fman.txt
>> index c00fb0d22c7b..020337f3c05f 100644
>> --- a/Documentation/devicetree/bindings/net/fsl-fman.txt
>> +++ b/Documentation/devicetree/bindings/net/fsl-fman.txt
>> @@ -410,6 +410,15 @@ PROPERTIES
>>  		The settings and programming routines for internal/external
>>  		MDIO are different. Must be included for internal MDIO.
>>  
>> +- fsl,erratum-a009885
>
> Adding errata properties doesn't work because then you have to update 
> your dtb to fix the issue where as if you use the compatible property 
> (specific to the SoC) you can fix the issue with just a (stable) kernel 
> update.
>
> Yes, I see we already have some, but doesn't mean we need more of them.

I agree. Unfortunately all users of the driver also use the same
compatible string, so there was no way I could think of that would not
involve rebuilding DTBs anyway. Given that situation, I chose to just
extend what was already there.

[PATCH v2 net 3/4] powerpc/fsl/dts: Enable WA for erratum A-009885 on fman3l MDIO buses

[Tobias Waldekranz]

This block is used in (at least) T1024 and T1040, including their
variants like T1023 etc.

Fixes: d55ad2967d89 ("powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan")
Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
---
 arch/powerpc/boot/dts/fsl/qoriq-fman3l-0.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/boot/dts/fsl/qoriq-fman3l-0.dtsi b/arch/powerpc/boot/dts/fsl/qoriq-fman3l-0.dtsi
index c90702b04a53..48e5cd61599c 100644
--- a/arch/powerpc/boot/dts/fsl/qoriq-fman3l-0.dtsi
+++ b/arch/powerpc/boot/dts/fsl/qoriq-fman3l-0.dtsi
@@ -79,6 +79,7 @@ mdio0: mdio@fc000 {
 		#size-cells = <0>;
 		compatible = "fsl,fman-memac-mdio", "fsl,fman-xmdio";
 		reg = <0xfc000 0x1000>;
+		fsl,erratum-a009885;
 	};
 
 	xmdio0: mdio@fd000 {
@@ -86,6 +87,7 @@ xmdio0: mdio@fd000 {
 		#size-cells = <0>;
 		compatible = "fsl,fman-memac-mdio", "fsl,fman-xmdio";
 		reg = <0xfd000 0x1000>;
+		fsl,erratum-a009885;
 	};
 };
 
-- 
2.25.1