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[PATCH v2] dt-bindings: mmc: Set maximum documented operating frequency as 384MHz

Bhupesh Sharma posted 1 patch 3 years, 8 months ago 
.../devicetree/bindings/mmc/mmc-controller.yaml     | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
[PATCH v2] dt-bindings: mmc: Set maximum documented operating frequency as 384MHz
Posted by Bhupesh Sharma 3 years, 8 months ago 
As Ulf noted in [1], the maximum operating frequency
documented in the mmc-controller device-tree bindings
should be updated to the maximum frequency supported
by the mmc controller(s).

Without this fix in place, the 'make dtbs_check' reports
issues with 'max-frequency' value for ipq8074 sdhci node:

  arch/arm64/boot/dts/qcom/ipq8074-hk01.dtb: mmc@7824900:
   max-frequency:0:0: 384000000 is greater than the maximum of 200000000

[1]. https://www.spinics.net/lists/kernel/msg4442049.html

Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 - v1 can be viewed here: https://lore.kernel.org/linux-arm-msm/20220725180916.2850228-1-bhupesh.sharma@linaro.org/
 - Rebased on linux-next/master

 .../devicetree/bindings/mmc/mmc-controller.yaml     | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
index ff5ce89e5111..802e3ca8be4d 100644
--- a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
+++ b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
@@ -88,11 +88,18 @@ properties:
     default: 1
 
   max-frequency:
-    description:
-      Maximum operating frequency of the bus.
+    description: |
+      Maximum operating frequency of the bus:
+        - for eMMC, the maximum supported frequency is 200MHz,
+        - for SD/SDIO cards the SDR104 mode has a max supported
+          frequency of 208MHz,
+        - some mmc host controllers do support a max frequency upto
+          384MHz.
+      So, lets keep the maximum supported value here.
+
     $ref: /schemas/types.yaml#/definitions/uint32
     minimum: 400000
-    maximum: 200000000
+    maximum: 384000000
 
   disable-wp:
     $ref: /schemas/types.yaml#/definitions/flag
-- 
2.35.3
Re: [PATCH v2] dt-bindings: mmc: Set maximum documented operating frequency as 384MHz
Posted by Ulf Hansson 3 years, 8 months ago 
On Tue, 26 Jul 2022 at 10:45, Bhupesh Sharma <bhupesh.sharma@linaro.org> wrote:
>
> As Ulf noted in [1], the maximum operating frequency
> documented in the mmc-controller device-tree bindings
> should be updated to the maximum frequency supported
> by the mmc controller(s).
>
> Without this fix in place, the 'make dtbs_check' reports
> issues with 'max-frequency' value for ipq8074 sdhci node:
>
>   arch/arm64/boot/dts/qcom/ipq8074-hk01.dtb: mmc@7824900:
>    max-frequency:0:0: 384000000 is greater than the maximum of 200000000
>
> [1]. https://www.spinics.net/lists/kernel/msg4442049.html
>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Rob Herring <robh@kernel.org>
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>

Applied for next, thanks!

Kind regards
Uffe


> ---
>  - v1 can be viewed here: https://lore.kernel.org/linux-arm-msm/20220725180916.2850228-1-bhupesh.sharma@linaro.org/
>  - Rebased on linux-next/master
>
>  .../devicetree/bindings/mmc/mmc-controller.yaml     | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> index ff5ce89e5111..802e3ca8be4d 100644
> --- a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> +++ b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> @@ -88,11 +88,18 @@ properties:
>      default: 1
>
>    max-frequency:
> -    description:
> -      Maximum operating frequency of the bus.
> +    description: |
> +      Maximum operating frequency of the bus:
> +        - for eMMC, the maximum supported frequency is 200MHz,
> +        - for SD/SDIO cards the SDR104 mode has a max supported
> +          frequency of 208MHz,
> +        - some mmc host controllers do support a max frequency upto
> +          384MHz.
> +      So, lets keep the maximum supported value here.
> +
>      $ref: /schemas/types.yaml#/definitions/uint32
>      minimum: 400000
> -    maximum: 200000000
> +    maximum: 384000000
>
>    disable-wp:
>      $ref: /schemas/types.yaml#/definitions/flag
> --
> 2.35.3
>
Re: [PATCH v2] dt-bindings: mmc: Set maximum documented operating frequency as 384MHz
Posted by Rob Herring 3 years, 8 months ago 
On Tue, 26 Jul 2022 14:15:20 +0530, Bhupesh Sharma wrote:
> As Ulf noted in [1], the maximum operating frequency
> documented in the mmc-controller device-tree bindings
> should be updated to the maximum frequency supported
> by the mmc controller(s).
> 
> Without this fix in place, the 'make dtbs_check' reports
> issues with 'max-frequency' value for ipq8074 sdhci node:
> 
>   arch/arm64/boot/dts/qcom/ipq8074-hk01.dtb: mmc@7824900:
>    max-frequency:0:0: 384000000 is greater than the maximum of 200000000
> 
> [1]. https://www.spinics.net/lists/kernel/msg4442049.html
> 
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Rob Herring <robh@kernel.org>
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> ---
>  - v1 can be viewed here: https://lore.kernel.org/linux-arm-msm/20220725180916.2850228-1-bhupesh.sharma@linaro.org/
>  - Rebased on linux-next/master
> 
>  .../devicetree/bindings/mmc/mmc-controller.yaml     | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Patchew 2.1-devel-ea86937

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