fix(gic600): implement workaround to forward highest priority interrupt

If the interrupt being targeted is released from the CPU before the
CLEAR command is sent to the CPU then a subsequent SET command may not
be delivered in a finite time. To workaround this, issue an unblocking
event by toggling GICR_CTLR.DPG* bits after clearing the cpu group
enable (EnableGrp* bits of GIC CPU interface register)
This fix is implemented as per the errata 2384374-part 2 workaround
mentioned here:
https://developer.arm.com/documentation/sden892601/latest/

Change-Id: I13926ceeb7740fa4c05cc5b43170e7ce49598f70
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/drivers/arm/gic/v3/gicv3.mk b/drivers/arm/gic/v3/gicv3.mk
index d7e3536..1d20ff3 100644
--- a/drivers/arm/gic/v3/gicv3.mk
+++ b/drivers/arm/gic/v3/gicv3.mk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2013-2020, Arm Limited and Contributors. All rights reserved.
+# Copyright (c) 2013-2022, Arm Limited and Contributors. All rights reserved.
 # Copyright (c) 2021, NVIDIA Corporation. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
@@ -12,6 +12,7 @@
 GICV3_OVERRIDE_DISTIF_PWR_OPS	?=	0
 GIC_ENABLE_V4_EXTN		?=	0
 GIC_EXT_INTID			?=	0
+GIC600_ERRATA_WA_2384374	?=	${GICV3_SUPPORT_GIC600}
 
 GICV3_SOURCES	+=	drivers/arm/gic/v3/gicv3_main.c		\
 			drivers/arm/gic/v3/gicv3_helpers.c	\
@@ -47,3 +48,7 @@
 # Set support for extended PPI and SPI range
 $(eval $(call assert_boolean,GIC_EXT_INTID))
 $(eval $(call add_define,GIC_EXT_INTID))
+
+# Set errata workaround for GIC600/GIC600AE
+$(eval $(call assert_boolean,GIC600_ERRATA_WA_2384374))
+$(eval $(call add_define,GIC600_ERRATA_WA_2384374))