On Sun, 2021-01-03 at 09:58 -0700, Rob Herring wrote:

On Wed, Dec 23, 2020 at 05:30:44PM +0800, EastL Lee wrote:

quoted

Document the devicetree bindings for MediaTek Command-Queue DMA controller
which could be found on MT6779 SoC or other similar Mediatek SoCs.

Signed-off-by: EastL Lee <redacted>
---
 .../devicetree/bindings/dma/mtk-cqdma.yaml         | 104 +++++++++++++++++++++

Use compatible string for filename:

OK

mediatek,cqdma.yaml

quoted

 1 file changed, 104 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/dma/mtk-cqdma.yaml

diff --git a/Documentation/devicetree/bindings/dma/mtk-cqdma.yaml b/Documentation/devicetree/bindings/dma/mtk-cqdma.yaml
new file mode 100644
index 0000000..a76a263
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/mtk-cqdma.yaml

@@ -0,0 +1,104 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/mtk-cqdma.yaml#

Don't forget to update this.

OK

quoted

+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek Command-Queue DMA controller Device Tree Binding
+
+maintainers:
+  - EastL Lee [off-list ref]
+
+description:
+  MediaTek Command-Queue DMA controller (CQDMA) on Mediatek SoC
+  is dedicated to memory-to-memory transfer through queue based
+  descriptor management.
+
+allOf:
+  - $ref: "dma-controller.yaml#"
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - mediatek,mt6765-cqdma
+          - mediatek,mt6779-cqdma
+      - const: mediatek,cqdma
+
+  reg:
+    minItems: 1
+    maxItems: 5
+    description:
+        A base address of MediaTek Command-Queue DMA controller,
+        a channel will have a set of base address.
+
+  interrupts:
+    minItems: 1
+    maxItems: 5
+    description:
+        A interrupt number of MediaTek Command-Queue DMA controller,
+        one interrupt number per dma-channels.
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: cqdma
+
+  dma-channel-mask:
+    description:
+       For DMA capability, We will know the addressing capability of
+       MediaTek Command-Queue DMA controller through dma-channel-mask.
+      minimum: 1
+      maximum: 63

Indentation is wrong here so this has no effect.

I'll fix it

A mask of 63 is 6 channels...

In my opinion, kernel dma mask if for 32/64 bit capability...
If I don't set dma mask I will get fail on DMATEST.

quoted

+
+  dma-channels:
+    description:
+      Number of DMA channels supported by MediaTek Command-Queue DMA
+      controller, support up to five.
+      minimum: 1
+      maximum: 5

Same here.

OK

Do you really need both dma-channels and dma-channel-mask? You should be 
able to get one from the other.

quoted

+
+  dma-requests:
+    description:
+      Number of DMA request (virtual channel) supported by MediaTek
+      Command-Queue DMA controller, support up to 32.
+      minimum: 1
+      maximum: 32

And here.

You are missing '#dma-cells' also.

OK I'll fix it.

quoted

+
+required:
+  - "#dma-cells"
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - dma-channel-mask
+  - dma-channels
+  - dma-requests
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/mt6779-clk.h>
+    cqdma: dma-controller@10212000 {
+        compatible = "mediatek,mt6779-cqdma";

This should fail validation because it doesn't match the schema. You ran 
'make dt_binding_check', right?

Yes, but I got other fail on kernel-5.10...

quoted

+        reg = <0x10212000 0x80>,
+            <0x10212080 0x80>,
+            <0x10212100 0x80>;
+        interrupts = <GIC_SPI 139 IRQ_TYPE_LEVEL_LOW>,
+            <GIC_SPI 140 IRQ_TYPE_LEVEL_LOW>,
+            <GIC_SPI 141 IRQ_TYPE_LEVEL_LOW>;
+        clocks = <&infracfg_ao CLK_INFRA_CQ_DMA>;
+        clock-names = "cqdma";
+        dma-channel-mask = <63>;

6 channels or...

quoted

+        dma-channels = <3>;

3?

3 channel, the mask is for DMATEST PASS.

quoted

+        dma-requests = <32>;
+        #dma-cells = <1>;
+    };
+
+...
-- 
1.9.1

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel