[PATCH v1 2/5] dt-bindings: mailbox: add binding for Microchip IPC mailbox driver

From: Valentina Fernandez
Date: Thu Sep 12 2024 - 12:48:58 EST


Add a dt-binding for the Microchip Inter-Processor Communication (IPC)
mailbox controller.

Signed-off-by: Valentina Fernandez <valentina.fernandezalanis@xxxxxxxxxxxxx>
---
.../bindings/mailbox/microchip,sbi-ipc.yaml | 115 ++++++++++++++++++
1 file changed, 115 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml b/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml
new file mode 100644
index 000000000000..dc2cbd5eb28f
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml
@@ -0,0 +1,115 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/microchip,sbi-ipc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip Inter-processor communication (IPC) mailbox controller
+
+maintainers:
+ - Valentina Fernandez <valentina.fernandezalanis@xxxxxxxxxxxxx>
+
+description:
+ The Microchip Inter-processor Communication (IPC) facilitates
+ message passing between processors using an interrupt signaling
+ mechanism.
+ This SBI interface is compatible with the Mi-V Inter-hart
+ Communication (IHC) IP.
+ The microchip,sbi-ipc compatible string is inteded for use by software
+ running in supervisor privileged mode (s-mode). The SoC-specific
+ compatibles are inteded for use by the SBI implementation in machine
+ mode (m-mode).
+
+properties:
+ compatible:
+ enum:
+ - microchip,sbi-ipc
+ - microchip,miv-ihc-rtl-v2
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ minItems: 1
+ maxItems: 5
+
+ interrupt-names:
+ minItems: 1
+ maxItems: 5
+
+ "#mbox-cells":
+ description:
+ For the SBI "device", the cell represents the global "logical" channel IDs.
+ The meaning of channel IDs are platform firmware dependent. The
+ SoC-specific compatibles are intended for use by the SBI implementation,
+ rather than s-mode software. There the cell would represent the physical
+ channel and do not vary depending on platform firmware.
+ const: 1
+
+ microchip,ihc-chan-disabled-mask:
+ description:
+ Represents the enable/disable state of the bi-directional IHC channels
+ within the MIV-IHC IP configuration. The mask is a 16-bit value, but only
+ the first 15 bits are utilized.Each of the bits corresponds to
+ one of the 15 IHC channels.
+ A bit set to '1' indicates that the corresponding channel is disabled,
+ and any read or write operations to that channel will return zero.
+ A bit set to '0' indicates that the corresponding channel is enabled
+ and will be accessible through its dedicated address range registers.
+ The remaining bit of the 16-bit mask is reserved and should be ignored.
+ The actual enable/disable state of each channel is determined by the
+ IP block’s configuration.
+ $ref: /schemas/types.yaml#/definitions/uint16
+ default: 0
+
+required:
+ - compatible
+ - interrupts
+ - interrupt-names
+ - "#mbox-cells"
+
+additionalProperties: false
+
+allOf:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: microchip,sbi-ipc
+ then:
+ properties:
+ reg: false
+ else:
+ required:
+ - reg
+
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: microchip,miv-ihc-rtl-v2
+ then:
+ properties:
+ interrupt-names:
+ items:
+ pattern: "^hart-[0-5]+$"
+
+examples:
+ - |
+ mailbox {
+ compatible = "microchip,sbi-ipc";
+ interrupt-parent = <&plic>;
+ interrupts = <180>, <179>, <178>;
+ interrupt-names = "hart-1", "hart-2", "hart-3";
+ #mbox-cells = <1>;
+ };
+ - |
+ mailbox@50000000 {
+ compatible = "microchip,miv-ihc-rtl-v2";
+ microchip,ihc-chan-disabled-mask= /bits/ 16 <0>;
+ reg = <0x50000000 0x1C000>;
+ interrupt-parent = <&plic>;
+ interrupts = <180>, <179>, <178>;
+ interrupt-names = "hart-1", "hart-2", "hart-3";
+ #mbox-cells = <1>;
+ };
--
2.34.1