[PATCH v7 1/2] dt-bindings: dma: Add bindings for intel LGM SOC

[Amireddy Mallikarjuna reddy]

Add DT bindings YAML schema for DMA controller driver
of Lightning Mountain(LGM) SoC.

Signed-off-by: Amireddy Mallikarjuna reddy <mallikarjunax.reddy@xxxxxxxxxxxxxxx>
---
v1:
- Initial version.

v2:
- Fix bot errors.

v3:
- No change.

v4:
- Address Thomas langer comments
  - use node name pattern as dma-controller as in common binding.
  - Remove "_" (underscore) in instance name.
  - Remove "port-" and "chan-" in attribute name for both 'dma-ports' & 'dma-channels' child nodes.

v5:
- Moved some of the attributes in 'dma-ports' & 'dma-channels' child nodes to dma client/consumer side as cells in 'dmas' properties.

v6:
- Add additionalProperties: false
- completely removed 'dma-ports' and 'dma-channels' child nodes.
- Moved channel dt properties to client side dmas.
- Use standard dma-channels and dma-channel-mask properties.
- Documented reset-names
- Add description for dma-cells

v7:
- modified compatible to oneof
- Reduced number of dma-cells to 3
- Fine tune the description of some properties.
---
 .../devicetree/bindings/dma/intel,ldma.yaml        | 135 +++++++++++++++++++++
 1 file changed, 135 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/dma/intel,ldma.yaml

diff --git a/Documentation/devicetree/bindings/dma/intel,ldma.yaml b/Documentation/devicetree/bindings/dma/intel,ldma.yaml
new file mode 100644
index 000000000000..d38143932b05
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/intel,ldma.yaml
@@ -0,0 +1,135 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/intel,ldma.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lightning Mountain centralized low speed DMA and high speed DMA controllers.
+
+maintainers:
+  - chuanhua.lei@xxxxxxxxx
+  - mallikarjunax.reddy@xxxxxxxxx
+
+allOf:
+  - $ref: "dma-controller.yaml#"
+
+properties:
+ $nodename:
+   pattern: "^dma-controller(@.*)?$"
+
+ compatible:
+  oneOf:
+   - const: intel,lgm-cdma
+   - const: intel,lgm-dma2tx
+   - const: intel,lgm-dma1rx
+   - const: intel,lgm-dma1tx
+   - const: intel,lgm-dma0tx
+   - const: intel,lgm-dma3
+   - const: intel,lgm-toe-dma30
+   - const: intel,lgm-toe-dma31
+
+ reg:
+  maxItems: 1
+
+ "#dma-cells":
+  const: 3
+  description:
+     The first cell is the peripheral's DMA request line.
+     The second cell is the peripheral's (port) number corresponding to the channel.
+     The third cell is the burst length of the channel.
+
+ dma-channels:
+  minimum: 1
+  maximum: 16
+
+ dma-channel-mask:
+  items:
+    minItems: 1
+
+ clocks:
+  maxItems: 1
+
+ resets:
+  maxItems: 1
+
+ reset-names:
+  items:
+    - const: ctrl
+
+ interrupts:
+  maxItems: 1
+
+ intel,dma-poll-cnt:
+   $ref: /schemas/types.yaml#definitions/uint32
+   description:
+     DMA descriptor polling counter is used to control the poling mechanism
+     for the descriptor fetching for all channels.
+
+ intel,dma-byte-en:
+   type: boolean
+   description:
+     DMA byte enable is only valid for DMA write(RX).
+     Byte enable(1) means DMA write will be based on the number of dwords
+     instead of the whole burst.
+
+ intel,dma-drb:
+    type: boolean
+    description:
+      DMA descriptor read back to make sure data and desc synchronization.
+
+ intel,dma-desc-in-sram:
+    type: boolean
+    description:
+       DMA descritpors in SRAM or not. Some old controllers descriptors
+       can be in DRAM or SRAM. The new ones are all in SRAM.
+
+ intel,dma-orrc:
+    $ref: /schemas/types.yaml#definitions/uint32
+    description:
+       DMA outstanding read counter value determine the number of
+       ORR-Outstanding Read Request. The maximum value is 16.
+
+ intel,dma-dburst-wr:
+    type: boolean
+    description:
+       Enable RX dynamic burst write. When it is enabled, the DMA does RX dynamic burst;
+       if it is disabled, the DMA RX will still support programmable fixed burst size of 2,4,8,16.
+       It only applies to RX DMA and memcopy DMA.
+
+required:
+ - compatible
+ - reg
+ - '#dma-cells'
+
+additionalProperties: false
+
+examples:
+ - |
+   dma0: dma-controller@e0e00000 {
+     compatible = "intel,lgm-cdma";
+     reg = <0xe0e00000 0x1000>;
+     #dma-cells = <3>;
+     dma-channels = <16>;
+     dma-channel-mask = <0xFFFF>;
+     interrupt-parent = <&ioapic1>;
+     interrupts = <82 1>;
+     resets = <&rcu0 0x30 0>;
+     reset-names = "ctrl";
+     clocks = <&cgu0 80>;
+     intel,dma-poll-cnt = <4>;
+     intel,dma-byte-en;
+     intel,dma-drb;
+   };
+ - |
+   dma3: dma-controller@ec800000 {
+     compatible = "intel,lgm-dma3";
+     reg = <0xec800000 0x1000>;
+     clocks = <&cgu0 71>;
+     resets = <&rcu0 0x10 9>;
+     #dma-cells = <3>;
+     intel,dma-poll-cnt = <16>;
+     intel,dma-desc-in-sram;
+     intel,dma-orrc = <16>;
+     intel,dma-byte-en;
+     intel,dma-dburst-wr;
+   };
-- 
2.11.0