new file mode 100644
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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/fsl,mu-msi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP i.MX Messaging Unit (MU) work as msi controller
+
+maintainers:
+ - Frank Li <Frank.Li@nxp.com>
+
+description: |
+ The Messaging Unit module enables two processors within the SoC to
+ communicate and coordinate by passing messages (e.g. data, status
+ and control) through the MU interface. The MU also provides the ability
+ for one processor to signal the other processor using interrupts.
+
+ Because the MU manages the messaging between processors, the MU uses
+ different clocks (from each side of the different peripheral buses).
+ Therefore, the MU must synchronize the accesses from one side to the
+ other. The MU accomplishes synchronization using two sets of matching
+ registers (Processor A-facing, Processor B-facing).
+
+ MU can work as msi interrupt controller to do doorbell
+
+allOf:
+ - $ref: /schemas/interrupt-controller.yaml#
+
+properties:
+ compatible:
+ enum:
+ - fsl,imx6sx-mu-msi
+ - fsl,imx7ulp-mu-msi
+ - fsl,imx8ulp-mu-msi
+ - fsl,imx8ulp-mu-msi-s4
+
+ reg:
+ minItems: 2
+
+ reg-names:
+ items:
+ - const: a
+ - const: b
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ power-domains:
+ maxItems: 2
+
+ power-domain-names:
+ items:
+ - const: a
+ - const: b
+
+ interrupt-controller: true
+
+ msi-controller: true
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - msi-controller
+ - interrupt-controller
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/firmware/imx/rsrc.h>
+
+ lsio_mu12: interrupt-controller@5d270000 {
+ compatible = "fsl,imx6sx-mu-msi";
+ msi-controller;
+ interrupt-controller;
+ reg = <0x5d270000 0x10000>, /* A side */
+ <0x5d300000 0x10000>; /* B side */
+ reg-names = "a", "b";
+ interrupts = <GIC_SPI 191 IRQ_TYPE_LEVEL_HIGH>;
+ power-domains = <&pd IMX_SC_R_MU_12A>,
+ <&pd IMX_SC_R_MU_12B>;
+ power-domain-names = "a", "b";
+ };
imx mu support generate irq by write a register. provide msi controller support so other driver can use it by standard msi interface. Signed-off-by: Frank Li <Frank.Li@nxp.com> --- .../interrupt-controller/fsl,mu-msi.yaml | 88 +++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 Documentation/devicetree/bindings/interrupt-controller/fsl,mu-msi.yaml