1 files changed, 53 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
index c7d2fa156678..375147e5a5fb 100644
--- a/Documentation/devicetree/bindings/arm/gic.txt
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -96,3 +96,56 @@ Example:
                       <0x2c006000 0x2000>;
                 interrupts = <1 9 0xf04>;
         };
+
+
+* GICv2m extension for MSI/MSI-x support (Optional)
+
+Certain revisions of GIC-400 supports MSI/MSI-x via V2M register frame(s).
+This is enabled by specifying v2m sub-node(s).
+
+Required properties:
+
+- compatible        : The value here should contain "arm,gic-v2m-frame".
+
+- msi-controller    : Identifies the node as an MSI controller.
+
+- reg               : GICv2m MSI interface register base and size
+
+Optional properties:
+
+- arm,msi-base-spi  : When the MSI_TYPER register contains an incorrect
+                      value, this property should contain the SPI base of
+                      the MSI frame, overriding the HW value.
+
+- arm,msi-num-spis  : When the MSI_TYPER register contains an incorrect
+                      value, this property should contain the number of
+                      SPIs assigned to the frame, overriding the HW value.
+
+Example:
+
+        interrupt-controller@e1101000 {
+                compatible = "arm,gic-400";
+                #interrupt-cells = <3>;
+                #address-cells = <2>;
+                #size-cells = <2>;
+                interrupt-controller;
+                interrupts = <1 8 0xf04>;
+                ranges = <0 0 0 0xe1100000 0 0x100000>;
+                reg = <0x0 0xe1110000 0 0x01000>,
+                      <0x0 0xe112f000 0 0x02000>,
+                      <0x0 0xe1140000 0 0x10000>,
+                      <0x0 0xe1160000 0 0x10000>;
+                v2m0: v2m@0x8000 {
+                        compatible = "arm,gic-v2m-frame";
+                        msi-controller;
+                        reg = <0x0 0x80000 0 0x1000>;
+                };
+
+                ....
+
+                v2mN: v2m@0x9000 {
+                        compatible = "arm,gic-v2m-frame";
+                        msi-controller;
+                        reg = <0x0 0x90000 0 0x1000>;
+                };
+        };