fix build with imxrt

hw/bsp/imxrt/family.c

@@ -79,7 +79,18 @@ void board_init(void)
   uart_config.baudRate_Bps = CFG_BOARD_UART_BAUDRATE;
   uart_config.enableTx = true;
   uart_config.enableRx = true;
-  LPUART_Init(UART_PORT, &uart_config, (CLOCK_GetPllFreq(kCLOCK_PllUsb1) / 6U) / (CLOCK_GetDiv(kCLOCK_UartDiv) + 1U));
+
+  uint32_t freq;
+  if (CLOCK_GetMux(kCLOCK_UartMux) == 0) /* PLL3 div6 80M */
+  {
+    freq = (CLOCK_GetPllFreq(kCLOCK_PllUsb1) / 6U) / (CLOCK_GetDiv(kCLOCK_UartDiv) + 1U);
+  }
+  else
+  {
+    freq = CLOCK_GetOscFreq() / (CLOCK_GetDiv(kCLOCK_UartDiv) + 1U);
+  }
+
+  LPUART_Init(UART_PORT, &uart_config, freq);
 
   //------------- USB0 -------------//
 

hw/bsp/imxrt/family.mk

@@ -1,5 +1,6 @@
 UF2_FAMILY_ID = 0x4fb2d5bd
-DEPS_SUBMODULES += hw/mcu/nxp/mcux-sdk
+SDK_DIR = hw/mcu/nxp/mcux-sdk
+DEPS_SUBMODULES += $(SDK_DIR)
 
 include $(TOP)/$(BOARD_PATH)/board.mk
 
@@ -17,7 +18,7 @@ CFLAGS += \
 # mcu driver cause following warnings
 CFLAGS += -Wno-error=unused-parameter -Wno-error=implicit-fallthrough=
 
-MCU_DIR = hw/mcu/nxp/mcux-sdk/devices/$(MCU_VARIANT)
+MCU_DIR = $(SDK_DIR)/devices/$(MCU_VARIANT)
 
 # All source paths should be relative to the top level.
 LD_FILE = $(MCU_DIR)/gcc/$(MCU_VARIANT)xxxxx_flexspi_nor.ld
@@ -32,16 +33,19 @@ SRC_C += \
 	$(MCU_DIR)/xip/fsl_flexspi_nor_boot.c \
 	$(MCU_DIR)/project_template/clock_config.c \
 	$(MCU_DIR)/drivers/fsl_clock.c \
-	$(MCU_DIR)/drivers/fsl_gpio.c \
-	$(MCU_DIR)/drivers/fsl_common.c \
-	$(MCU_DIR)/drivers/fsl_lpuart.c
+	$(SDK_DIR)/drivers/common/fsl_common.c \
+	$(SDK_DIR)/drivers/igpio/fsl_gpio.c \
+	$(SDK_DIR)/drivers/lpuart/fsl_lpuart.c
 
 INC += \
 	$(TOP)/$(BOARD_PATH) \
 	$(TOP)/$(MCU_DIR)/../../CMSIS/Include \
 	$(TOP)/$(MCU_DIR) \
-	$(TOP)/$(MCU_DIR)/drivers \
 	$(TOP)/$(MCU_DIR)/project_template \
+	$(TOP)/$(MCU_DIR)/drivers \
+	$(TOP)/$(SDK_DIR)/drivers/common \
+	$(TOP)/$(SDK_DIR)/drivers/igpio \
+	$(TOP)/$(SDK_DIR)/drivers/lpuart
 
 SRC_S += $(MCU_DIR)/gcc/startup_$(MCU_VARIANT).S