From 15ed653fa49a7ddda2034db5d722fd6c2d439dd8 Mon Sep 17 00:00:00 2001
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Mon, 19 Sep 2016 11:59:32 +0530
Subject: [PATCH] ppc/xics: An ICS with offset 0 is assumed to be uninitialized

This will make life easier for dealing with dynamically configured
ICSes such as PHB3

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 include/hw/ppc/xics.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/hw/ppc/xics.h b/include/hw/ppc/xics.h
index 2db9f938d3..5aac67ad89 100644
--- a/include/hw/ppc/xics.h
+++ b/include/hw/ppc/xics.h
@@ -149,7 +149,7 @@ struct ICSState {
 
 static inline bool ics_valid_irq(ICSState *ics, uint32_t nr)
 {
-    return (nr >= ics->offset)
+    return (ics->offset != 0) && (nr >= ics->offset)
         && (nr < (ics->offset + ics->nr_irqs));
 }