Add bare-metal TDK IMU ESKF fusion

soc/software/gps_system/Makefile

@@ -7,6 +7,14 @@ BSP_UART_CLOCK_HZ ?= 50000000
 
 APP_SRCS := \
 	gps_test.c \
+	src/tdk_icm42688.c \
+	src/eskf.c \
+	src/fusion_motion.c \
+	src/fusion_engine.c \
+	src/fusion_bus.c \
+	src/fusion_gps_adapter.c \
+	src/navigation_fusion.c \
+	src/gps_fusion_publisher.c \
 	src/gps_ip.c \
 	src/gps_interrupt_handlers.c \
 	src/gps_time_anchor.c \
@@ -15,9 +23,16 @@ APP_SRCS := \
 	src/NavEquations.c \
 	src/matrixLib.c
 
+BSP_SRCS := init.c uart.c plic.c irq.c spi_flash.c pmod_spi.c
+
+TDK_IMU_ODR_HZ ?= 500
+GPS_NAV_SOLVE_TIMER_TICKS ?= 50
+
 include ../common/app.mk
 
 CFLAGS += -Iheader
+CFLAGS += -DTDK_IMU_ODR_HZ=$(TDK_IMU_ODR_HZ) \
+	-DGPS_NAV_SOLVE_TIMER_TICKS=$(GPS_NAV_SOLVE_TIMER_TICKS)
 LDLIBS += -lm
 
 ifeq ($(GPS_DEBUG),1)