Add device tree binding documentation for the Black Sesame Technologies
(BST) DWCMSHC SDHCI controller.
This binding describes the required and optional properties for the
bst,dwcmshc-sdhci compatible controller, including register layout,
interrupts, bus width, clock configuration, and other controller-specific
features.
---
Changes for v2:
- Simplified description, removed redundant paragraphs
- Updated $schema to reference mmc-specific scheme
- Corrected compatible to add soc name
(bst,c1200-dwcmshc-sdhci)
- Removed all redundant property descriptions
- Dropped invalid mmc_crm_base/size properties, use reg for all address
ranges
- Cleaned up required properties to only essential entries
- Standardized example DTS format, fixed reg syntax and property
ordering
- Removed additionalProperties: true
Signed-off-by: Ge Gordon <gordon.ge@bst.ai>
Signed-off-by: Albert Yang <yangzh0906@thundersoft.com>
---
.../bindings/mmc/bst,dwcmshc-sdhci.yaml | 67 +++++++++++++++++++
1 file changed, 67 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
diff --git a/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
new file mode 100644
index 000000000000..699dc404caac
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mmc/bst,dwcmshc-sdhci.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Black Sesame Technologies DWCMSHC SDHCI Controller
+
+maintainers:
+ - Ge Gordon <gordon.ge@bst.ai>
+
+allOf:
+ - $ref: mmc-controller.yaml#
+
+properties:
+ compatible:
+ const: bst,c1200-dwcmshc-sdhci
+
+ reg:
+ maxItems: 2
+ description: |
+ Register base addresses and sizes for the SDHCI controller.
+ First entry is the core SDHCI registers, second entry is the
+ CRM registers.
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ clock-names:
+ items:
+ - const: core
+
+ memory-region:
+ maxItems: 1
+
+ dma-coherent: true
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - clocks
+ - clock-names
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+ mmc@22200000 {
+ compatible = "bst,c1200-dwcmshc-sdhci";
+ reg = <0x0 0x22200000 0x0 0x1000>,
+ <0x0 0x23006000 0x0 0x1000>;
+ interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clk_mmc>;
+ clock-names = "core";
+ memory-region = <&mmc0_reserved>;
+ max-frequency = <200000000>;
+ bus-width = <8>;
+ non-removable;
+ dma-coherent;
+ status = "disabled";
+ };
--
2.25.1On Wed, Jul 02, 2025 at 05:44:40PM +0800, Albert Yang wrote:
> Add device tree binding documentation for the Black Sesame Technologies
> (BST) DWCMSHC SDHCI controller.
>
> This binding describes the required and optional properties for the
> bst,dwcmshc-sdhci compatible controller, including register layout,
> interrupts, bus width, clock configuration, and other controller-specific
> features.
>
> ---
> Changes for v2:
> - Simplified description, removed redundant paragraphs
> - Updated $schema to reference mmc-specific scheme
> - Corrected compatible to add soc name
> (bst,c1200-dwcmshc-sdhci)
> - Removed all redundant property descriptions
> - Dropped invalid mmc_crm_base/size properties, use reg for all address
> ranges
> - Cleaned up required properties to only essential entries
> - Standardized example DTS format, fixed reg syntax and property
> ordering
> - Removed additionalProperties: true
>
> Signed-off-by: Ge Gordon <gordon.ge@bst.ai>
> Signed-off-by: Albert Yang <yangzh0906@thundersoft.com>
> ---
> .../bindings/mmc/bst,dwcmshc-sdhci.yaml | 67 +++++++++++++++++++
> 1 file changed, 67 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
>
> diff --git a/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
> new file mode 100644
> index 000000000000..699dc404caac
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
> @@ -0,0 +1,67 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mmc/bst,dwcmshc-sdhci.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Black Sesame Technologies DWCMSHC SDHCI Controller
> +
> +maintainers:
> + - Ge Gordon <gordon.ge@bst.ai>
> +
> +allOf:
> + - $ref: mmc-controller.yaml#
> +
> +properties:
> + compatible:
> + const: bst,c1200-dwcmshc-sdhci
> +
> + reg:
> + maxItems: 2
> + description: |
> + Register base addresses and sizes for the SDHCI controller.
> + First entry is the core SDHCI registers, second entry is the
> + CRM registers.
items:
- description: Core SDHCI registers
- description: CRM registers
Though what CRM is should be defined.
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 1
> +
> + clock-names:
> + items:
> + - const: core
> +
> + memory-region:
> + maxItems: 1
> +
> + dma-coherent: true
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - clock-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> + mmc@22200000 {
> + compatible = "bst,c1200-dwcmshc-sdhci";
> + reg = <0x0 0x22200000 0x0 0x1000>,
> + <0x0 0x23006000 0x0 0x1000>;
> + interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&clk_mmc>;
> + clock-names = "core";
> + memory-region = <&mmc0_reserved>;
> + max-frequency = <200000000>;
> + bus-width = <8>;
> + non-removable;
> + dma-coherent;
> + status = "disabled";
Examples should be enabled. Drop.
> + };
> --
> 2.25.1
>
Hi Rob, Thank you for the feedback. > items: > - description: Core SDHCI registers > - description: CRM registers Fixed. I've updated the reg property to use the items list format as suggested. > Examples should be enabled. Drop. Fixed. I've removed the `status = "disabled";` line from the example. Best regards, Albert Yang
On Wed, 02 Jul 2025 17:44:40 +0800, Albert Yang wrote: > Add device tree binding documentation for the Black Sesame Technologies > (BST) DWCMSHC SDHCI controller. > > This binding describes the required and optional properties for the > bst,dwcmshc-sdhci compatible controller, including register layout, > interrupts, bus width, clock configuration, and other controller-specific > features. > > --- > Changes for v2: > - Simplified description, removed redundant paragraphs > - Updated $schema to reference mmc-specific scheme > - Corrected compatible to add soc name > (bst,c1200-dwcmshc-sdhci) > - Removed all redundant property descriptions > - Dropped invalid mmc_crm_base/size properties, use reg for all address > ranges > - Cleaned up required properties to only essential entries > - Standardized example DTS format, fixed reg syntax and property > ordering > - Removed additionalProperties: true > > Signed-off-by: Ge Gordon <gordon.ge@bst.ai> > Signed-off-by: Albert Yang <yangzh0906@thundersoft.com> > --- > .../bindings/mmc/bst,dwcmshc-sdhci.yaml | 67 +++++++++++++++++++ > 1 file changed, 67 insertions(+) > create mode 100644 Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml > My bot found errors running 'make dt_binding_check' on your patch: yamllint warnings/errors: dtschema/dtc warnings/errors: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.example.dtb: mmc@22200000 (bst,c1200-dwcmshc-sdhci): reg: [[0, 572522496], [0, 4096], [0, 587227136], [0, 4096]] is too long from schema $id: http://devicetree.org/schemas/mmc/bst,dwcmshc-sdhci.yaml# doc reference errors (make refcheckdocs): See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20250702094444.3523973-5-yangzh0906@thundersoft.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 Rob,
Thank you for the automated dt-binding check report.
> My bot found errors running 'make dt_binding_check' on your patch:
>
> /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.example.dtb: mmc@22200000 (bst,c1200-dwcmshc-sdhci): reg: [[0, 572522496], [0, 4096], [0, 587227136], [0, 4096]] is too long
> from schema $id: http://devicetree.org/schemas/mmc/bst,dwcmshc-sdhci.yaml#
I have identified and fixed this issue. The problem was that the binding example used 64-bit addresses but lacked the proper bus wrapper with #address-cells and #size-cells settings.
Fix Applied:
I've wrapped the example in a proper bus node with the correct address/size-cells, following the pattern used in sdhci-am654.yaml for handling 64-bit addresses:
examples:
- |
#include <dt-bindings/interrupt-controller/arm-gic.h>
#include <dt-bindings/interrupt-controller/irq.h>
bus {
#address-cells = <2>;
#size-cells = <2>;
mmc@22200000 {
compatible = "bst,c1200-dwcmshc-sdhci";
reg = <0x0 0x22200000 0x0 0x1000>,
<0x0 0x23006000 0x0 0x1000>;
interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clk_mmc>;
clock-names = "core";
memory-region = <&mmc0_reserved>;
max-frequency = <200000000>;
bus-width = <8>;
non-removable;
dma-coherent;
};
};
This approach is consistent with how sdhci-am654.yaml handles multiple reg entries with 64-bit addresses, and matches the actual usage in our bstc1200.dtsi file where the soc node defines #address-cells = <2> and #size-cells = <2>.
Verification:
After the fix, make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml passes without errors.
Best regards,
Albert Yang
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