[PATCH] powerpc: Support new property called interrupt-parents

@@ -1769,7 +1769,65 @@ If the interrupt-parent property is not defined for a node, it's
 interrupt parent is assumed to be an ancestor in the node's
 _device tree_ hierarchy.
 
-3) OpenPIC Interrupt Controllers
+3) interrupt-parents property
+-----------------------------
+
+For devices that generate interrupts to multiple interrupt
+controllers, the  interrupt-parent representation
+is not sufficient because it only describes a single
+interrupt parent. The 'interrupt-parents' property can be used
+to represent this (note the plural in the property name).
+
+The interrupt-parents property consists of one or more 
+interrupt parent phandle values each representing the interrupt
+parent for the corresponding interrupt specifier in the interrupts
+property:
+
+  interrupt-parents = <parent-phandle0 parent-phandle1 ... parent-phandleN>
+  interrupts = <int-specifier0 int-specifier1 ... int-specifierN>
+
+It is required that the number of interrupts encoded in the interrupt-parents
+property exacly match the number of interrupt specifiers in the interrupts
+property.
+
+See the example below:
+
+   pic0: pic@700 {
+       interrupt-controller;
+       #address-cells = <0>;
+       #interrupt-cells = <2>;
+       reg = <700 100>;
+       device_type = "open-pic";
+   };
+
+   pic1: pic@800 {
+       interrupt-controller;
+       #address-cells = <0>;
+       #interrupt-cells = <2>;
+       reg = <800 100>;
+       device_type = "open-pic";
+   };
+
+   ethernet@25000 {
+       device_type = "network";
+       reg = <25000 1000>;
+       ...
+       interrupt-parents = <&pic0 &pic0 &pic1>;
+       interrupts        = <13 3  14 3  18 3>;
+   };
+
+In the above example, the interrupts property and the interrupt-parents
+property defines three interrupts. The first 2 interrupt lines are
+routed to irqs 0x13 and 0x14 on pic0.  The 3rd interrupt line is 
+routed to irq 0x18 on pic1.
+
+Note: each interrupt parent in the interrupt-parents array can
+potentially specify a different value for #interrupt-cells.  The number
+of #interrupt-cells for each parent must be determined to correctly
+parse the interrupts property.
+
+
+4) OpenPIC Interrupt Controllers
 --------------------------------
 
 OpenPIC interrupt controllers require 2 cells to encode

@@ -958,10 +958,11 @@ static int of_irq_map_oldworld(struct device_node *device, int index,
 
 int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq)
 {
-	struct device_node *p;
-	const u32 *intspec, *tmp, *addr;
-	u32 intsize, intlen;
-	int res;
+	struct device_node *p = NULL;
+	const u32 *intspec, *intprop, *intp, *tmp, *addr, *parp;
+	u32 intsize = 0;
+	u32 intlen, intplen;
+	int res,i;
 
 	DBG("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);
 

@@ -970,36 +971,85 @@ int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq
 		return of_irq_map_oldworld(device, index, out_irq);
 
 	/* Get the interrupts property */
-	intspec = get_property(device, "interrupts", &intlen);
-	if (intspec == NULL)
+	intprop = get_property(device, "interrupts", &intlen);
+	if (intprop == NULL)
 		return -EINVAL;
 	intlen /= sizeof(u32);
 
 	/* Get the reg property (if any) */
 	addr = get_property(device, "reg", NULL);
 
-	/* Look for the interrupt parent. */
-	p = of_irq_find_parent(device);
-	if (p == NULL)
-		return -EINVAL;
+	/* look for interrupt-parents */
+	intp = get_property(device, "interrupt-parents", &intplen);
+	if (intp == NULL) {
 
-	/* Get size of interrupt specifier */
-	tmp = get_property(p, "#interrupt-cells", NULL);
-	if (tmp == NULL) {
-		of_node_put(p);
-		return -EINVAL;
-	}
-	intsize = *tmp;
+		/* Look for the interrupt parent. */
+		p = of_irq_find_parent(device);
+		if (p == NULL)
+			return -EINVAL;
 
-	DBG(" intsize=%d intlen=%d\n", intsize, intlen);
+		/* Get size of interrupt specifier */
+		tmp = get_property(p, "#interrupt-cells", NULL);
+		if (tmp == NULL) {
+			of_node_put(p);
+			return -EINVAL;
+		}
+		intsize = *tmp;
+	
+		DBG(" intsize=%d intlen=%d\n", intsize, intlen);
+	
+		/* Check index */
+		if ((index + 1) * intsize > intlen)
+			return -EINVAL;
 
-	/* Check index */
-	if ((index + 1) * intsize > intlen)
-		return -EINVAL;
+		/* compute pointer to interrupt specifier */
+		intspec = intprop + index * intsize;
+
+	} else {  /* this node has multiple interrupt parents */
+
+		intplen /= sizeof(u32); /* # of cells */
+
+		if ((index+1) > intplen)
+			return -EINVAL; /* index is out of bounds */
+
+		intspec = intprop;
+
+		for (i=0; i < intplen; i++) {
+
+			p = of_find_node_by_phandle(intp[i]);
+
+			/* starting with the specified int parent, search up the int tree for interrupt-cells */
+			while (p && get_property(p, "#interrupt-cells", NULL) == NULL) {
+
+				parp = get_property(p, "interrupt-parent", NULL);
+				if (parp == NULL) {
+					p = of_get_parent(p);
+				} else {
+					p = of_find_node_by_phandle(*parp);
+				}
+			}
+
+			/* Get size of interrupt specifier */
+			tmp = get_property(p, "#interrupt-cells", NULL);
+			if (tmp == NULL) {
+				of_node_put(p);
+				return -EINVAL;
+			}
+			intsize = *tmp;
+
+			if (index == i)
+				break;
+
+			/* advance pointer to next int specifier */
+			intspec = intspec + intsize;
+		}
+
+		DBG(" index=%d intspec[0]=%d intsize=%d \n", i, *intspec, intsize);
+
+	}
 
 	/* Get new specifier and map it */
-	res = of_irq_map_raw(p, intspec + index * intsize, intsize,
-			     addr, out_irq);
+	res = of_irq_map_raw(p, intspec, intsize, addr, out_irq);
 	of_node_put(p);
 	return res;
 }