这个文件包含了gicv2的源码文件!!!
#Copyright © 2020, Arm Limited. All rights reserved.
#SPDX-License-Identifier: BSD-3-Clause
#No support for extended PPI and SPI range
GIC_EXT_INTID := 0
GICV2_SOURCES += drivers/arm/gic/v2/gicv2_main.c
drivers/arm/gic/v2/gicv2_helpers.c
drivers/arm/gic/v2/gicdv2_helpers.c
#Set GICv2 build option
$(eval $(call add_define,GIC_EXT_INTID))