GIC: Add API to get interrupt active status

API documentation updated.

Change-Id: I6d61785af0d5330930c709de971a904dc7c3516c
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/drivers/arm/gic/common/gic_common.c b/drivers/arm/gic/common/gic_common.c
index 6535813..71155a9 100644
--- a/drivers/arm/gic/common/gic_common.c
+++ b/drivers/arm/gic/common/gic_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -273,6 +273,14 @@
 	gicd_write_icpendr(base, id, (1 << bit_num));
 }
 
+unsigned int gicd_get_isactiver(uintptr_t base, unsigned int id)
+{
+	unsigned int bit_num = id & ((1 << ISACTIVER_SHIFT) - 1);
+	unsigned int reg_val = gicd_read_isactiver(base, id);
+
+	return (reg_val >> bit_num) & 0x1;
+}
+
 void gicd_set_isactiver(uintptr_t base, unsigned int id)
 {
 	unsigned bit_num = id & ((1 << ISACTIVER_SHIFT) - 1);