diff --git a/include/dt-bindings/interrupt-controller/arm-gic.h b/include/dt-bindings/interrupt-controller/arm-gic.h
index fbe07da..803cd9c 100644
--- a/include/dt-bindings/interrupt-controller/arm-gic.h
+++ b/include/dt-bindings/interrupt-controller/arm-gic.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2021, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2019-2021, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -9,21 +9,18 @@
 #ifndef _DT_BINDINGS_INTERRUPT_CONTROLLER_ARM_GIC_H
 #define _DT_BINDINGS_INTERRUPT_CONTROLLER_ARM_GIC_H
 
+#include <dt-bindings/interrupt-controller/irq.h>
+
 /* interrupt specifier cell 0 */
 
 #define GIC_SPI 0
 #define GIC_PPI 1
 
-#define IRQ_TYPE_NONE		0
-#define IRQ_TYPE_EDGE_RISING	1
-#define IRQ_TYPE_EDGE_FALLING	2
-#define IRQ_TYPE_EDGE_BOTH	(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
-#define IRQ_TYPE_LEVEL_HIGH	4
-#define IRQ_TYPE_LEVEL_LOW	8
-
 /*
  * Interrupt specifier cell 2.
+ * The flags in irq.h are valid, plus those below.
  */
 #define GIC_CPU_MASK_RAW(x) ((x) << 8)
+#define GIC_CPU_MASK_SIMPLE(num) GIC_CPU_MASK_RAW((1 << (num)) - 1)
 
 #endif
diff --git a/include/dt-bindings/interrupt-controller/irq.h b/include/dt-bindings/interrupt-controller/irq.h
new file mode 100644
index 0000000..94e7f95
--- /dev/null
+++ b/include/dt-bindings/interrupt-controller/irq.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * This header provides constants for most IRQ bindings.
+ *
+ * Most IRQ bindings include a flags cell as part of the IRQ specifier.
+ * In most cases, the format of the flags cell uses the standard values
+ * defined in this header.
+ */
+
+#ifndef _DT_BINDINGS_INTERRUPT_CONTROLLER_IRQ_H
+#define _DT_BINDINGS_INTERRUPT_CONTROLLER_IRQ_H
+
+#define IRQ_TYPE_NONE		0
+#define IRQ_TYPE_EDGE_RISING	1
+#define IRQ_TYPE_EDGE_FALLING	2
+#define IRQ_TYPE_EDGE_BOTH	(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
+#define IRQ_TYPE_LEVEL_HIGH	4
+#define IRQ_TYPE_LEVEL_LOW	8
+
+#endif