Merge pull request #312 from hathach/develop

house keeping work

16 files changed, 366 insertions, 47 deletions

diff --git a/docs/boards.md b/docs/boards.md
index 3d2f39c5c..8955674c8 100644
--- a/docs/boards.md
+++ b/docs/boards.md
@@ -26,6 +26,8 @@ This code base already had supported for a handful of following boards (sorted a
 - [Adafruit CLUE](https://www.adafruit.com/product/4500)
 - [Adafruit Feather nRF52840 Express](https://www.adafruit.com/product/4062)
 - [Adafruit Feather nRF52840 Sense](https://www.adafruit.com/product/4516)
+- [Arduino Nano 33 BLE](https://store.arduino.cc/usa/nano-33-ble)
+- [Arduino Nano 33 BLE Sense](https://store.arduino.cc/usa/nano-33-ble-sense)
 - [Maker Diary nRF52840 MDK Dongle](https://wiki.makerdiary.com/nrf52840-mdk-usb-dongle)
 - [Nordic nRF52840 Development Kit (aka pca10056)](https://www.nordicsemi.com/Software-and-Tools/Development-Kits/nRF52840-DK)
 - [Nordic nRF52840 Dongle (aka pca10059)](https://www.nordicsemi.com/Software-and-Tools/Development-Kits/nRF52840-Dongle)
diff --git a/examples/make.mk b/examples/make.mk
index 25b618896..f2a8b979e 100644
--- a/examples/make.mk
+++ b/examples/make.mk
@@ -1,82 +1,69 @@
-#
+# ---------------------------------------
 # Common make definition for all examples
-#
+# ---------------------------------------
 
-# Compiler
-ifeq ($(BOARD), msp_exp430f5529lp)
-  CROSS_COMPILE = msp430-elf-
-else ifeq ($(BOARD), fomu)
-  CROSS_COMPILE = riscv-none-embed-
-else
-  CROSS_COMPILE = arm-none-eabi-
+#-------------- Select the board to build for. ------------
+BOARD_LIST = $(sort $(subst /.,,$(subst $(TOP)/hw/bsp/,,$(wildcard $(TOP)/hw/bsp/*/.))))
+
+ifeq ($(filter $(BOARD),$(BOARD_LIST)),)
+  $(info You must provide a BOARD parameter with 'BOARD=', supported boards are:)
+  $(foreach b,$(BOARD_LIST),$(info - $(b)))
+  $(error Invalid BOARD specified)
 endif
-CC = $(CROSS_COMPILE)gcc
-CXX = $(CROSS_COMPILE)g++
-OBJCOPY = $(CROSS_COMPILE)objcopy
-SIZE = $(CROSS_COMPILE)size
-MKDIR = mkdir
-SED = sed
-CP = cp
-RM = rm
-PYTHON ?= python
 
+# Handy check parameter function
 check_defined = \
     $(strip $(foreach 1,$1, \
     $(call __check_defined,$1,$(strip $(value 2)))))
 __check_defined = \
     $(if $(value $1),, \
     $(error Undefined make flag: $1$(if $2, ($2))))
-
-
-define newline
-
-
-endef
-
-# Select the board to build for.
-ifeq ($(BOARD),)
-  $(info You must provide a BOARD parameter with 'BOARD=')
-  $(info Supported boards are:)
-  $(info $(sort $(subst /.,,$(subst $(TOP)/hw/bsp/, $(newline)-,$(wildcard $(TOP)/hw/bsp/*/.)))))
-  $(error BOARD not defined)
-else
-  ifeq ($(wildcard $(TOP)/hw/bsp/$(BOARD)/.),)
-    $(error Invalid BOARD specified)
-  endif
-endif
-
+    
 # Build directory
 BUILD = _build/build-$(BOARD)
 
-# Board specific
+# Board specific define
 include $(TOP)/hw/bsp/$(BOARD)/board.mk
 
+#-------------- Cross Compiler  ------------
+# Can be set by board, default to ARM GCC
+CROSS_COMPILE ?= arm-none-eabi-
+
+CC = $(CROSS_COMPILE)gcc
+CXX = $(CROSS_COMPILE)g++
+OBJCOPY = $(CROSS_COMPILE)objcopy
+SIZE = $(CROSS_COMPILE)size
+MKDIR = mkdir
+SED = sed
+CP = cp
+RM = rm
+
+#-------------- Source files and compiler flags --------------
+
 # Include all source C in board folder
 SRC_C += hw/bsp/board.c
 SRC_C += $(subst $(TOP)/,,$(wildcard $(TOP)/hw/bsp/$(BOARD)/*.c))
 
 # Compiler Flags
 CFLAGS += \
+	-fdata-sections \
+	-ffunction-sections \
 	-fsingle-precision-constant \
 	-fno-strict-aliasing \
 	-Wdouble-promotion \
-	-Wno-endif-labels \
 	-Wstrict-prototypes \
 	-Wall \
 	-Wextra \
 	-Werror \
-	-Werror-implicit-function-declaration \
 	-Wfatal-errors \
+	-Werror-implicit-function-declaration \
 	-Wfloat-equal \
 	-Wundef \
 	-Wshadow \
 	-Wwrite-strings \
 	-Wsign-compare \
 	-Wmissing-format-attribute \
-	-Wno-deprecated-declarations \
-	-Wunreachable-code \
-	-ffunction-sections \
-	-fdata-sections
+	-Wunreachable-code
 
 # This causes lots of warning with nrf5x build due to nrfx code
 # CFLAGS += -Wcast-align
diff --git a/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.c b/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.c
new file mode 100644
index 000000000..941716c2f
--- /dev/null
+++ b/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.c
@@ -0,0 +1,216 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This file is part of the TinyUSB stack.
+ */
+
+#include "bsp/board.h"
+
+#include "nrfx.h"
+#include "nrfx/hal/nrf_gpio.h"
+#include "nrfx/drivers/include/nrfx_power.h"
+#include "nrfx/drivers/include/nrfx_uarte.h"
+
+#ifdef SOFTDEVICE_PRESENT
+#include "nrf_sdm.h"
+#include "nrf_soc.h"
+#endif
+
+/*------------------------------------------------------------------*/
+/* MACRO TYPEDEF CONSTANT ENUM
+ *------------------------------------------------------------------*/
+#define _PINNUM(port, pin)    ((port)*32 + (pin))
+
+#define LED_PIN         _PINNUM(0, 24)
+#define LED_STATE_ON    0
+
+#define BUTTON_PIN      _PINNUM(1, 11) // D2
+
+#define UART_RX_PIN     _PINNUM(1, 10)
+#define UART_TX_PIN     _PINNUM(1, 3)
+
+static nrfx_uarte_t _uart_id = NRFX_UARTE_INSTANCE(0);
+
+// tinyusb function that handles power event (detected, ready, removed)
+// We must call it within SD's SOC event handler, or set it as power event handler if SD is not enabled.
+extern void tusb_hal_nrf_power_event(uint32_t event);
+
+void board_init(void)
+{
+  // stop LF clock just in case we jump from application without reset
+  NRF_CLOCK->TASKS_LFCLKSTOP = 1UL;
+
+  // Config clock source: XTAL or RC in sdk_config.h
+  NRF_CLOCK->LFCLKSRC = (uint32_t)((CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos) & CLOCK_LFCLKSRC_SRC_Msk);
+  NRF_CLOCK->TASKS_LFCLKSTART = 1UL;
+
+  // LED
+  nrf_gpio_cfg_output(LED_PIN);
+  board_led_write(false);
+
+  // Button
+  nrf_gpio_cfg_input(BUTTON_PIN, NRF_GPIO_PIN_PULLUP);
+
+  // 1ms tick timer
+  SysTick_Config(SystemCoreClock/1000);
+
+  // UART
+  nrfx_uarte_config_t uart_cfg =
+  {
+    .pseltxd   = UART_TX_PIN,
+    .pselrxd   = UART_RX_PIN,
+    .pselcts   = NRF_UARTE_PSEL_DISCONNECTED,
+    .pselrts   = NRF_UARTE_PSEL_DISCONNECTED,
+    .p_context = NULL,
+    .baudrate  = NRF_UARTE_BAUDRATE_115200, // CFG_BOARD_UART_BAUDRATE
+    .interrupt_priority = 7,
+    .hal_cfg = {
+      .hwfc      = NRF_UARTE_HWFC_DISABLED,
+      .parity    = NRF_UARTE_PARITY_EXCLUDED,
+    }
+  };
+
+  nrfx_uarte_init(&_uart_id, &uart_cfg, NULL); //uart_handler);
+
+#if TUSB_OPT_DEVICE_ENABLED
+  // Priorities 0, 1, 4 (nRF52) are reserved for SoftDevice
+  // 2 is highest for application
+  NVIC_SetPriority(USBD_IRQn, 2);
+
+  // USB power may already be ready at this time -> no event generated
+  // We need to invoke the handler based on the status initially
+  uint32_t usb_reg;
+
+#ifdef SOFTDEVICE_PRESENT
+  uint8_t sd_en = false;
+  sd_softdevice_is_enabled(&sd_en);
+
+  if ( sd_en ) {
+    sd_power_usbdetected_enable(true);
+    sd_power_usbpwrrdy_enable(true);
+    sd_power_usbremoved_enable(true);
+
+    sd_power_usbregstatus_get(&usb_reg);
+  }else
+#endif
+  {
+    // Power module init
+    const nrfx_power_config_t pwr_cfg = { 0 };
+    nrfx_power_init(&pwr_cfg);
+
+    // Register tusb function as USB power handler
+    const nrfx_power_usbevt_config_t config = { .handler = (nrfx_power_usb_event_handler_t) tusb_hal_nrf_power_event };
+    nrfx_power_usbevt_init(&config);
+
+    nrfx_power_usbevt_enable();
+
+    usb_reg = NRF_POWER->USBREGSTATUS;
+  }
+
+  if ( usb_reg & POWER_USBREGSTATUS_VBUSDETECT_Msk ) tusb_hal_nrf_power_event(NRFX_POWER_USB_EVT_DETECTED);
+  if ( usb_reg & POWER_USBREGSTATUS_OUTPUTRDY_Msk  ) tusb_hal_nrf_power_event(NRFX_POWER_USB_EVT_READY);
+#endif
+}
+
+//--------------------------------------------------------------------+
+// Board porting API
+//--------------------------------------------------------------------+
+
+void board_led_write(bool state)
+{
+  nrf_gpio_pin_write(LED_PIN, state ? LED_STATE_ON : (1-LED_STATE_ON));
+}
+
+uint32_t board_button_read(void)
+{
+  // button is active LOW
+  return (nrf_gpio_pin_read(BUTTON_PIN) ? 0 : 1);
+}
+
+int board_uart_read(uint8_t* buf, int len)
+{
+  (void) buf; (void) len;
+  return 0;
+//  return NRFX_SUCCESS == nrfx_uart_rx(&_uart_id, buf, (size_t) len) ? len : 0;
+}
+
+int board_uart_write(void const * buf, int len)
+{
+  return (NRFX_SUCCESS == nrfx_uarte_tx(&_uart_id, (uint8_t const*) buf, (size_t) len)) ? len : 0;
+}
+
+#if CFG_TUSB_OS == OPT_OS_NONE
+volatile uint32_t system_ticks = 0;
+void SysTick_Handler (void)
+{
+  system_ticks++;
+}
+
+uint32_t board_millis(void)
+{
+  return system_ticks;
+}
+#endif
+
+#ifdef SOFTDEVICE_PRESENT
+// process SOC event from SD
+uint32_t proc_soc(void)
+{
+  uint32_t soc_evt;
+  uint32_t err = sd_evt_get(&soc_evt);
+
+  if (NRF_SUCCESS == err)
+  {
+    /*------------- usb power event handler -------------*/
+    int32_t usbevt = (soc_evt == NRF_EVT_POWER_USB_DETECTED   ) ? NRFX_POWER_USB_EVT_DETECTED:
+                     (soc_evt == NRF_EVT_POWER_USB_POWER_READY) ? NRFX_POWER_USB_EVT_READY   :
+                     (soc_evt == NRF_EVT_POWER_USB_REMOVED    ) ? NRFX_POWER_USB_EVT_REMOVED : -1;
+
+    if ( usbevt >= 0) tusb_hal_nrf_power_event(usbevt);
+  }
+
+  return err;
+}
+
+uint32_t proc_ble(void)
+{
+  // do nothing with ble
+  return NRF_ERROR_NOT_FOUND;
+}
+
+void SD_EVT_IRQHandler(void)
+{
+  // process BLE and SOC until there is no more events
+  while( (NRF_ERROR_NOT_FOUND != proc_ble()) || (NRF_ERROR_NOT_FOUND != proc_soc()) )
+  {
+
+  }
+}
+
+void nrf_error_cb(uint32_t id, uint32_t pc, uint32_t info)
+{
+  (void) id;
+  (void) pc;
+  (void) info;
+}
+#endif
diff --git a/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.ld b/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.ld
new file mode 100755
index 000000000..f570740b6
--- /dev/null
+++ b/hw/bsp/arduino_nano33_ble/arduino_nano33_ble.ld
@@ -0,0 +1,32 @@
+/* Linker script to configure memory regions. */
+
+SEARCH_DIR(.)
+GROUP(-lgcc -lc -lnosys)
+
+MEMORY
+{
+  FLASH (rx) : ORIGIN = 0x10000, LENGTH = 0xf0000
+  RAM_NVIC (rwx) : ORIGIN = 0x20000000, LENGTH = 0x100
+  RAM_CRASH_DATA (rwx) : ORIGIN = (0x20000000 + 0x100), LENGTH = 0x100
+  RAM (rwx) : ORIGIN = ((0x20000000 + 0x100) + 0x100), LENGTH = (0x40000 - (0x100 + 0x100))
+}
+
+SECTIONS
+{
+  . = ALIGN(4);
+  .svc_data :
+  {
+    PROVIDE(__start_svc_data = .);
+    KEEP(*(.svc_data))
+    PROVIDE(__stop_svc_data = .);
+  } > RAM
+  
+  .fs_data :
+  {
+    PROVIDE(__start_fs_data = .);
+    KEEP(*(.fs_data))
+    PROVIDE(__stop_fs_data = .);
+  } > RAM
+} INSERT AFTER .data;
+
+INCLUDE "nrf52_common.ld"
diff --git a/hw/bsp/arduino_nano33_ble/board.mk b/hw/bsp/arduino_nano33_ble/board.mk
new file mode 100644
index 000000000..d217d37c0
--- /dev/null
+++ b/hw/bsp/arduino_nano33_ble/board.mk
@@ -0,0 +1,63 @@
+CFLAGS += \
+  -flto \
+  -mthumb \
+  -mabi=aapcs \
+  -mcpu=cortex-m4 \
+  -mfloat-abi=hard \
+  -mfpu=fpv4-sp-d16 \
+  -DCFG_TUSB_MCU=OPT_MCU_NRF5X \
+  -DNRF52840_XXAA \
+  -DCONFIG_GPIO_AS_PINRESET
+
+# nrfx issue undef _ARMCC_VERSION usage https://github.com/NordicSemiconductor/nrfx/issues/49
+CFLAGS += -Wno-error=undef -Wno-error=unused-parameter
+
+# due to tusb_hal_nrf_power_event
+GCCVERSION = $(firstword $(subst ., ,$(shell arm-none-eabi-gcc -dumpversion)))
+ifeq ($(shell expr $(GCCVERSION) \>= 8), 1)
+CFLAGS += -Wno-error=cast-function-type
+endif
+
+# All source paths should be relative to the top level.
+#LD_FILE = hw/bsp/$(BOARD)/linker_script.ld
+LD_FILE = hw/bsp/$(BOARD)/arduino_nano33_ble.ld
+
+LDFLAGS += -L$(TOP)/hw/mcu/nordic/nrfx/mdk
+
+SRC_C += \
+  hw/mcu/nordic/nrfx/drivers/src/nrfx_power.c \
+  hw/mcu/nordic/nrfx/drivers/src/nrfx_uarte.c \
+  hw/mcu/nordic/nrfx/mdk/system_nrf52840.c
+
+INC += \
+  $(TOP)/lib/CMSIS_4/CMSIS/Include \
+  $(TOP)/hw/mcu/nordic \
+  $(TOP)/hw/mcu/nordic/nrfx \
+  $(TOP)/hw/mcu/nordic/nrfx/mdk \
+  $(TOP)/hw/mcu/nordic/nrfx/hal \
+  $(TOP)/hw/mcu/nordic/nrfx/drivers/include \
+  $(TOP)/hw/mcu/nordic/nrfx/drivers/src \
+
+SRC_S += hw/mcu/nordic/nrfx/mdk/gcc_startup_nrf52840.S
+
+ASFLAGS += -D__HEAP_SIZE=0
+
+# For TinyUSB port source
+VENDOR = nordic
+CHIP_FAMILY = nrf5x
+
+# For freeRTOS port source
+FREERTOS_PORT = ARM_CM4F
+
+# For flash-jlink target
+JLINK_DEVICE = nRF52840_xxAA
+JLINK_IF = swd
+
+# flash using bossac (as part of Nano33 BSP tools)
+# can be found in arduino15/packages/arduino/tools/bossac/
+# Add it to your PATH or change BOSSAC variable to match your installation
+BOSSAC = bossac
+
+flash: $(BUILD)/$(BOARD)-firmware.bin
+	@:$(call check_defined, SERIAL, example: SERIAL=/dev/ttyACM0)
+	$(BOSSAC) --port=$(SERIAL) -U -i -e -w $^ -R
diff --git a/hw/bsp/circuitplayground_express/samd21g18a_flash.ld b/hw/bsp/circuitplayground_express/samd21g18a_flash.ld
index 7fc42171b..f0c93340c 100644
--- a/hw/bsp/circuitplayground_express/samd21g18a_flash.ld
+++ b/hw/bsp/circuitplayground_express/samd21g18a_flash.ld
@@ -42,6 +42,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0x2000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/feather_m0_express/samd21g18a_flash.ld b/hw/bsp/feather_m0_express/samd21g18a_flash.ld
index 7fc42171b..f0c93340c 100644
--- a/hw/bsp/feather_m0_express/samd21g18a_flash.ld
+++ b/hw/bsp/feather_m0_express/samd21g18a_flash.ld
@@ -42,6 +42,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0x2000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/feather_m4_express/samd51g19a_flash.ld b/hw/bsp/feather_m4_express/samd51g19a_flash.ld
index cf5db3800..f1a021d75 100644
--- a/hw/bsp/feather_m4_express/samd51g19a_flash.ld
+++ b/hw/bsp/feather_m4_express/samd51g19a_flash.ld
@@ -44,6 +44,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0xC000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/fomu/board.mk b/hw/bsp/fomu/board.mk
index b824b6979..403a7fb95 100644
--- a/hw/bsp/fomu/board.mk
+++ b/hw/bsp/fomu/board.mk
@@ -5,6 +5,9 @@ CFLAGS += \
   -nostdlib \
   -DCFG_TUSB_MCU=OPT_MCU_VALENTYUSB_EPTRI
 
+# Cross Compiler for RISC-V
+CROSS_COMPILE = riscv-none-embed-
+
 MCU_DIR = hw/mcu/fomu
 BSP_DIR = hw/bsp/fomu
 
diff --git a/hw/bsp/itsybitsy_m0/samd21g18a_flash.ld b/hw/bsp/itsybitsy_m0/samd21g18a_flash.ld
index 7fc42171b..f0c93340c 100644
--- a/hw/bsp/itsybitsy_m0/samd21g18a_flash.ld
+++ b/hw/bsp/itsybitsy_m0/samd21g18a_flash.ld
@@ -42,6 +42,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0x2000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/itsybitsy_m4/samd51g19a_flash.ld b/hw/bsp/itsybitsy_m4/samd51g19a_flash.ld
index cf5db3800..f1a021d75 100644
--- a/hw/bsp/itsybitsy_m4/samd51g19a_flash.ld
+++ b/hw/bsp/itsybitsy_m4/samd51g19a_flash.ld
@@ -44,6 +44,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0xC000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/metro_m0_express/samd21g18a_flash.ld b/hw/bsp/metro_m0_express/samd21g18a_flash.ld
index 7fc42171b..f0c93340c 100644
--- a/hw/bsp/metro_m0_express/samd21g18a_flash.ld
+++ b/hw/bsp/metro_m0_express/samd21g18a_flash.ld
@@ -42,6 +42,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0x2000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/metro_m4_express/samd51g19a_flash.ld b/hw/bsp/metro_m4_express/samd51g19a_flash.ld
index cf5db3800..f1a021d75 100644
--- a/hw/bsp/metro_m4_express/samd51g19a_flash.ld
+++ b/hw/bsp/metro_m4_express/samd51g19a_flash.ld
@@ -44,6 +44,8 @@ MEMORY
 /* The stack size used by the application. NOTE: you need to adjust according to your application. */
 STACK_SIZE = DEFINED(STACK_SIZE) ? STACK_SIZE : DEFINED(__stack_size__) ? __stack_size__ : 0xC000;
 
+ENTRY(Reset_Handler)
+
 /* Section Definitions */
 SECTIONS
 {
diff --git a/hw/bsp/msp_exp430f5529lp/board.mk b/hw/bsp/msp_exp430f5529lp/board.mk
index 13e3b7217..8e857eb66 100644
--- a/hw/bsp/msp_exp430f5529lp/board.mk
+++ b/hw/bsp/msp_exp430f5529lp/board.mk
@@ -6,6 +6,9 @@ CFLAGS += \
 
 #-mmcu=msp430f5529
 
+# Cross Compiler for MSP430
+CROSS_COMPILE = msp430-elf-
+
 # All source paths should be relative to the top level.
 LD_FILE = hw/mcu/ti/msp430/msp430-gcc-support-files/include/msp430f5529.ld
 LDINC += $(TOP)/hw/mcu/ti/msp430/msp430-gcc-support-files/include
diff --git a/hw/bsp/seeeduino_xiao/samd21g18a_flash.ld b/hw/bsp/seeeduino_xiao/samd21g18a_flash.ld
index bae38a881..cf11c4c35 100644
--- a/hw/bsp/seeeduino_xiao/samd21g18a_flash.ld
+++ b/hw/bsp/seeeduino_xiao/samd21g18a_flash.ld
@@ -52,8 +52,7 @@ SECTIONS
         . = ALIGN(4);
         _sfixed = .;
         KEEP(*(.vectors .vectors.*))
-        *(.text*)
-	*(.gnu.linkonce.t.*)
+        *(.text .text.* .gnu.linkonce.t.*)
         *(.glue_7t) *(.glue_7)
         *(.rodata .rodata* .gnu.linkonce.r.*)
         *(.ARM.extab* .gnu.linkonce.armextab.*)
diff --git a/tools/build_all.py b/tools/build_all.py
index 08964bb76..0437bcaac 100644
--- a/tools/build_all.py
+++ b/tools/build_all.py
@@ -88,7 +88,7 @@ for example in all_examples:
                 fail_count += 1
 
             build_duration = time.monotonic() - start_time
-            print(build_format.format(example, board, success, "{:.2f}".format(build_duration), flash_size, sram_size))
+            print(build_format.format(example, board, success, "{:.2f}s".format(build_duration), flash_size, sram_size))
 
             if build_result.returncode != 0:
                 print(build_result.stdout.decode("utf-8"))