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,c1200-dwcmshc-sdhci compatible controller, including register layout,
interrupts, bus width, clock configuration, and other controller-specific
features.
Signed-off-by: Albert Yang <yangzh0906@thundersoft.com>
---
Changes for v4:
- Remove Signed-off-by line for Ge Gordon
- Change `$ref: mmc-controller.yaml#` to `$ref: sdhci-common.yaml#`
- Change compatible string from `bst,c1200-dwcmshc-sdhci` to `bst,c1200-sdhci`
Changes for v3:
- Switch reg schema from maxItems to explicit items with per-entry descriptions
- Improve example: add irq.h include and wrap under a bus node with address/size cells
- Drop status = "disabled" from example; keep example concise
- Add Signed-off-by: Ge Gordon
Changes for v2:
- Simplify description, remove redundant paragraphs
- Update $schema to reference mmc-specific scheme
- Correct compatible to add soc name (bst,c1200-dwcmshc-sdhci)
- Remove all redundant property descriptions
- Drop invalid mmc_crm_base/size properties, use reg for all address ranges
- Clean up required properties to only essential entries
- Standardize example DTS format, fix reg syntax and property ordering
- Remove additionalProperties: true
---
.../devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml | 70 ++++++++++++++++++++++
1 file changed, 70 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..7f16e6db39690cb7621d167bf7bc492f814ea693
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$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:
+ - $ref: sdhci-common.yaml#
+
+properties:
+ compatible:
+ const: bst,c1200-sdhci
+
+ reg:
+ items:
+ - description: Core SDHCI registers
+ - description: CRM registers
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ clock-names:
+ items:
+ - const: core
+
+ memory-region:
+ maxItems: 1
+
+ dma-coherent: true
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - clocks
+ - clock-names
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ bus {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ mmc@22200000 {
+ compatible = "bst,c1200-dwcmshc-sdhci";
+ reg = <0x0 0x22200000 0x0 0x1000>,
+ <0x0 0x23006000 0x0 0x1000>;
+ interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clk_mmc>;
+ clock-names = "core";
+ memory-region = <&mmc0_reserved>;
+ max-frequency = <200000000>;
+ bus-width = <8>;
+ non-removable;
+ dma-coherent;
+ };
+ };
--
2.43.0On Tue, Sep 23, 2025 at 02:10:10PM +0800, Albert Yang wrote:
> Add device tree binding documentation for the Black Sesame Technologies
> (BST) DWCMSHC SDHCI controller.
>
> This binding describes the required and optional properties for the
> bst,c1200-dwcmshc-sdhci compatible controller, including register layout,
> interrupts, bus width, clock configuration, and other controller-specific
> features.
>
> Signed-off-by: Albert Yang <yangzh0906@thundersoft.com>
>
> ---
> Changes for v4:
Thanks for the changelog here, but the subject should have 'PATCH v4' so
various tools work.
> - Remove Signed-off-by line for Ge Gordon
> - Change `$ref: mmc-controller.yaml#` to `$ref: sdhci-common.yaml#`
> - Change compatible string from `bst,c1200-dwcmshc-sdhci` to `bst,c1200-sdhci`
>
> Changes for v3:
> - Switch reg schema from maxItems to explicit items with per-entry descriptions
> - Improve example: add irq.h include and wrap under a bus node with address/size cells
> - Drop status = "disabled" from example; keep example concise
> - Add Signed-off-by: Ge Gordon
>
> Changes for v2:
> - Simplify description, remove redundant paragraphs
> - Update $schema to reference mmc-specific scheme
> - Correct compatible to add soc name (bst,c1200-dwcmshc-sdhci)
> - Remove all redundant property descriptions
> - Drop invalid mmc_crm_base/size properties, use reg for all address ranges
> - Clean up required properties to only essential entries
> - Standardize example DTS format, fix reg syntax and property ordering
> - Remove additionalProperties: true
> ---
> .../devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml | 70 ++++++++++++++++++++++
Filename should match compatible.
> 1 file changed, 70 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..7f16e6db39690cb7621d167bf7bc492f814ea693
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml
> @@ -0,0 +1,70 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$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: sdhci-common.yaml#
> +
> +properties:
> + compatible:
> + const: bst,c1200-sdhci
> +
> + reg:
> + items:
> + - description: Core SDHCI registers
> + - description: CRM registers
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 1
> +
> + clock-names:
> + items:
> + - const: core
Not really any point in having -names when there is only 1 entry.
> +
> + memory-region:
> + maxItems: 1
Having this is odd. Please add a description saying what it is for.
> +
> + dma-coherent: true
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - clock-names
> +
> +unevaluatedProperties: false
> +
> +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;
> + };
> + };
>
> --
> 2.43.0
>
On Tue, Sep 23, 2025 at 08:56:20AM -0500, Rob Herring wrote:
> On Tue, Sep 23, 2025 at 02:10:10PM +0800, Albert Yang wrote:
> > Add device tree binding documentation for the Black Sesame Technologies
> > (BST) DWCMSHC SDHCI controller.
Hi Rob,
Thanks for the review.
> Thanks for the changelog here, but the subject should have 'PATCH v4' so
> various tools work.
Understood. Will ensure v5 has the proper subject format with 'PATCH v5'.
> Filename should match compatible.
Fixed. Renamed from bst,dwcmshc-sdhci.yaml to bst,c1200-dwcmshc.yaml
to match the compatible string "bst,c1200-dwcmshc", and updated the
$id field accordingly.
> Not really any point in having -names when there is only 1 entry.
Agreed. I've dropped clock-names from the schema, DTS, and removed it
from required properties.
> Having this is odd. Please add a description saying what it is for.
Added description for memory-region: "Reserved memory region for bounce
buffer. Required due to controller's 32-bit DMA limitation while system
RAM is above 32-bit addressable range."
Updated example:
mmc@22200000 {
compatible = "bst,c1200-dwcmshc";
reg = <0x0 0x22200000 0x0 0x1000>,
<0x0 0x23006000 0x0 0x1000>;
interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&clk_mmc>;
memory-region = <&mmc0_reserved>;
max-frequency = <200000000>;
bus-width = <8>;
non-removable;
dma-coherent;
};
Please let me know if you have any other concerns or suggestions for
this binding. I'll send v5 with these fixes.
Thanks,
Albert Yang
On Tue, 23 Sep 2025 14:10:10 +0800, Albert Yang wrote: > Add device tree binding documentation for the Black Sesame Technologies > (BST) DWCMSHC SDHCI controller. > > This binding describes the required and optional properties for the > bst,c1200-dwcmshc-sdhci compatible controller, including register layout, > interrupts, bus width, clock configuration, and other controller-specific > features. > > Signed-off-by: Albert Yang <yangzh0906@thundersoft.com> > > --- > Changes for v4: > - Remove Signed-off-by line for Ge Gordon > - Change `$ref: mmc-controller.yaml#` to `$ref: sdhci-common.yaml#` > - Change compatible string from `bst,c1200-dwcmshc-sdhci` to `bst,c1200-sdhci` > > Changes for v3: > - Switch reg schema from maxItems to explicit items with per-entry descriptions > - Improve example: add irq.h include and wrap under a bus node with address/size cells > - Drop status = "disabled" from example; keep example concise > - Add Signed-off-by: Ge Gordon > > Changes for v2: > - Simplify description, remove redundant paragraphs > - Update $schema to reference mmc-specific scheme > - Correct compatible to add soc name (bst,c1200-dwcmshc-sdhci) > - Remove all redundant property descriptions > - Drop invalid mmc_crm_base/size properties, use reg for all address ranges > - Clean up required properties to only essential entries > - Standardize example DTS format, fix reg syntax and property ordering > - Remove additionalProperties: true > --- > .../devicetree/bindings/mmc/bst,dwcmshc-sdhci.yaml | 70 ++++++++++++++++++++++ > 1 file changed, 70 insertions(+) > My bot found errors running 'make dt_binding_check' on your patch: yamllint warnings/errors: dtschema/dtc warnings/errors: Documentation/devicetree/bindings/mmc/bst,dwcmshc-sdhci.example.dtb: /example-0/bus/mmc@22200000: failed to match any schema with compatible: ['bst,c1200-dwcmshc-sdhci'] doc reference errors (make refcheckdocs): See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20250923-v4-patch-final-v1-4-2283ad7cbf88@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.
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