ThreadX在gcc下的移植

本文介绍ThreadX在arm-none-eabi-gcc编译器下的移植方法。

1、ThreadX介绍和源码获取

threadx的介绍和源码获取请参考之前的博文：ThreadX在mdk(AC5)中的移植。

2、准备工作

本篇主要介绍threadx在corex-m7上的移植，编译器使用arm-none-eabi-gcc。
在移植之前，需要先搭建cortex-m7的gcc工程模板。模板也无需自己从头写，可以借助于stm32的开发工具STM32CubeMX。如何使用STM32CubeMX不是本文的重点，本文的重点在threadx的移植上面。读者可以自行查阅如何使用STM32CubeMX创建gcc工程。
工程创建后可适当对Makefile文件进行修改，读者可以参考本文的Makefile。

3、ThreadX移植过程

3.1、拷贝ThreadX的源文件

1、在自己的工程目录下创建threadx-6.2.1文件夹。
2、将ThreadX源码目录中的ports和common目录拷贝到threadx-6.2.1中。
3、ports目录下仅保留ports\cortex_m7\gnu目录。
4、将ports\cortex_m7\gnu\example_build\tx_initialize_low_level.S文件拷贝到ports\cortex_m7\gnu\src中。

拷贝后的ports\cortex_m7\gnu\src：

3.2、Makefile文件修改

1、添加threadx-6.2.1/common/src目录和
threadx-6.2.1/ports/cortex_m7/gnu/src目录到SRC_DIR变量中：

SRC_DIR += \
threadx-6.2.1/common/src \
threadx-6.2.1/ports/cortex_m7/gnu/src

2、添加threadx-6.2.1/common/inc目录和
threadx-6.2.1/ports/cortex_m7/gnu/inc目录到C_INCLUDES变量中：

C_INCLUDES +=  \
-Ithreadx-6.2.1/common/inc \
-Ithreadx-6.2.1/ports/cortex_m7/gnu/inc

3、添加.S文件的编译规则
4、修改后的Makefile文件如下：

# ------------------------------------------------
# Generic Makefile (based on gcc)
# ------------------------------------------------

######################################
# target
######################################
TARGET = stm32f7

######################################
# building variables
######################################
# debug build?
DEBUG = 0
# optimization
OPT = -Os
# float printf
FLOAT_PTINT = 0

#######################################
# paths
#######################################
# Build path
BUILD_DIR = build

######################################
# source
######################################
# Sources dir
SRC_DIR := \
stm32f7_libraries/cmsis_m7/DeviceSupport/gcc \
stm32f7_libraries/stm32f7_stdperiph_driver/src \
threadx-6.2.1/common/src \
threadx-6.2.1/ports/cortex_m7/gnu/src \
application/main

# C sources
C_SOURCES := $(foreach dir, $(SRC_DIR), $(wildcard $(dir)/*.c))

# ASM sources
ASM_SOURCES := $(foreach dir, $(SRC_DIR), $(wildcard $(dir)/*.s))
ASM_SOURCES2 := $(foreach dir, $(SRC_DIR), $(wildcard $(dir)/*.S))

#######################################
# binaries
#######################################
PREFIX = arm-none-eabi-
# The gcc compiler bin path can be either defined in make command via GCC_PATH variable (> make GCC_PATH=xxx)
# either it can be added to the PATH environment variable.
ifdef GCC_PATH
CC = $(GCC_PATH)/$(PREFIX)gcc
AS = $(GCC_PATH)/$(PREFIX)gcc -x assembler-with-cpp
CP = $(GCC_PATH)/$(PREFIX)objcopy
SZ = $(GCC_PATH)/$(PREFIX)size
else
CC = $(PREFIX)gcc
AS = $(PREFIX)gcc -x assembler-with-cpp
CP = $(PREFIX)objcopy
SZ = $(PREFIX)size
endif
HEX = $(CP) -O ihex
BIN = $(CP) -O binary -S

#######################################
# CFLAGS
#######################################
# cpu
CPU = -mcpu=cortex-m7

# fpu
FPU = -mfpu=fpv5-d16

# float-abi
FLOAT-ABI = -mfloat-abi=soft

# mcu
MCU = $(CPU) -mthumb $(FPU) $(FLOAT-ABI)

# macros for gcc
# AS defines
AS_DEFS =

# C defines
C_DEFS =  \
-D__VFP_FP__ \
-D__SOFTFP__ \
-DTX_INCLUDE_USER_DEFINE_FILE

# AS includes
AS_INCLUDES =

# C includes
C_INCLUDES =  \
-Istm32f7_libraries/stm32f7_stdperiph_driver/inc \
-Istm32f7_libraries/cmsis_m7/CoreSupport \
-Ithreadx-6.2.1/common/inc \
-Ithreadx-6.2.1/ports/cortex_m7/gnu/inc \
-Iapplication/main

# compile gcc flags
ASFLAGS = $(MCU) $(AS_DEFS) $(AS_INCLUDES) $(OPT) -Wall -fdata-sections -ffunction-sections

CFLAGS += $(MCU) $(C_DEFS) $(C_INCLUDES) $(OPT) -std=c99 -Wall -fdata-sections -ffunction-sections

ifeq ($(DEBUG), 1)
CFLAGS += -g -gdwarf-2
endif

# Generate dependency information
CFLAGS += -MMD -MP -MF"$(@:%.o=%.d)"

#######################################
# LDFLAGS
#######################################
# link script
LDSCRIPT = stm32f7_libraries/cmsis_m7/DeviceSupport/gcc/startup_stm32f7_flash.ld

# libraries
LIBS = -lc -lm -lnosys
LIBDIR =
LDFLAGS = $(MCU) -specs=nano.specs -T$(LDSCRIPT) $(LIBDIR) $(LIBS) -Wl,-Map=$(BUILD_DIR)/$(TARGET).map,--cref -Wl,--gc-sections

ifeq ($(FLOAT_PTINT), 1)
LDFLAGS += -Wl,-u_printf_float
endif

# default action: build all
all: $(BUILD_DIR)/$(TARGET).elf $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).bin


#######################################
# build the application
#######################################
# list of objects
OBJECTS = $(addprefix $(BUILD_DIR)/,$(notdir $(C_SOURCES:.c=.o)))
vpath %.c $(sort $(dir $(C_SOURCES)))
# list of ASM program objects
OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(ASM_SOURCES:.s=.o)))
vpath %.s $(sort $(dir $(ASM_SOURCES)))
OBJECTS += $(addprefix $(BUILD_DIR)/,$(notdir $(ASM_SOURCES2:.S=.o)))
vpath %.S $(sort $(dir $(ASM_SOURCES2)))

$(BUILD_DIR)/%.o: %.c Makefile | $(BUILD_DIR)
	$(CC) -c $(CFLAGS) -Wa,-a,-ad,-alms=$(BUILD_DIR)/$(notdir $(<:.c=.lst)) $< -o $@

$(BUILD_DIR)/%.o: %.s Makefile | $(BUILD_DIR)
	$(AS) -c $(CFLAGS) $< -o $@

$(BUILD_DIR)/%.o: %.S Makefile | $(BUILD_DIR)
	$(AS) -c $(CFLAGS) $< -o $@

$(BUILD_DIR)/$(TARGET).elf: $(OBJECTS) Makefile
	$(CC) $(OBJECTS) $(LDFLAGS) -o $@
	$(SZ) $@

$(BUILD_DIR)/%.hex: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
	$(HEX) $< $@

$(BUILD_DIR)/%.bin: $(BUILD_DIR)/%.elf | $(BUILD_DIR)
	$(BIN) $< $@

$(BUILD_DIR):
	mkdir $@

#######################################
# clean up
#######################################
clean:
	-rm -fR $(BUILD_DIR)

#######################################
# dependencies
#######################################
-include $(wildcard $(BUILD_DIR)/*.d)

# *** EOF ***

3.3、链接脚本修改

1、链接脚本中增加 __RAM_segment_used_end__变量
2、修改后的lds文件

/*
******************************************************************************
**

**  File        : LinkerScript.ld
**
**  Author		: 
**
**  Abstract    : Linker script for stm32_m7 series
**                1024Kbytes FLASH and 1024Kbytes RAM
**
**                Set heap size, stack size and stack location according
**                to application requirements.
**
**                Set memory bank area and size if external memory is used.
**
**  Target      : Cortex-M7
**
**  Distribution: The file is distributed “as is,” without any warranty
**                of any kind.
**
*********************************************************************
*****************************************************************************
*/

/* Entry Point */
ENTRY(Reset_Handler)

/* Highest address of the user mode stack */
_estack = ORIGIN(RAM) + LENGTH(RAM);    /* end of RAM */
/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0xA00;      /* required amount of heap  */
_Min_Stack_Size = 0x800; /* required amount of stack */

/* Specify the memory areas */
MEMORY
{
RAM (xrw)      : ORIGIN = 0x20000000, LENGTH = 128K
FLASH (rx)     : ORIGIN = 0x80000000, LENGTH = 1024K
}

/* Define output sections */
SECTIONS
{
  /* The startup code goes first into FLASH */
  .isr_vector :
  {
    . = ALIGN(4);
    KEEP(*(.isr_vector)) /* Startup code */
    . = ALIGN(4);
  } >FLASH

  /* The program code and other data goes into FLASH */
  .text :
  {
    . = ALIGN(4);
    *(.text)           /* .text sections (code) */
    *(.text*)          /* .text* sections (code) */
    *(.glue_7)         /* glue arm to thumb code */
    *(.glue_7t)        /* glue thumb to arm code */
    *(.eh_frame)

    KEEP (*(.init))
    KEEP (*(.fini))

    . = ALIGN(4);
    _etext = .;        /* define a global symbols at end of code */
  } >FLASH

  /* Constant data goes into FLASH */
  .rodata :
  {
    . = ALIGN(4);
    *(.rodata)         /* .rodata sections (constants, strings, etc.) */
    *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
    . = ALIGN(4);
  } >FLASH

  .ARM.extab   : { *(.ARM.extab* .gnu.linkonce.armextab.*) } >FLASH
  .ARM : {
    __exidx_start = .;
    *(.ARM.exidx*)
    __exidx_end = .;
  } >FLASH

  .preinit_array     :
  {
    PROVIDE_HIDDEN (__preinit_array_start = .);
    KEEP (*(.preinit_array*))
    PROVIDE_HIDDEN (__preinit_array_end = .);
  } >FLASH
  .init_array :
  {
    PROVIDE_HIDDEN (__init_array_start = .);
    KEEP (*(SORT(.init_array.*)))
    KEEP (*(.init_array*))
    PROVIDE_HIDDEN (__init_array_end = .);
  } >FLASH
  .fini_array :
  {
    PROVIDE_HIDDEN (__fini_array_start = .);
    KEEP (*(SORT(.fini_array.*)))
    KEEP (*(.fini_array*))
    PROVIDE_HIDDEN (__fini_array_end = .);
  } >FLASH

  /* used by the startup to initialize data */
  _sidata = LOADADDR(.data);

  /* Initialized data sections goes into RAM, load LMA copy after code */
  .data : 
  {
    . = ALIGN(4);
    _sdata = .;        /* create a global symbol at data start */
    *(.data)           /* .data sections */
    *(.data*)          /* .data* sections */

    . = ALIGN(4);
    _edata = .;        /* define a global symbol at data end */
  } >RAM AT> FLASH

  
  /* Uninitialized data section */
  . = ALIGN(4);
  .bss :
  {
    /* This is used by the startup in order to initialize the .bss secion */
    _sbss = .;         /* define a global symbol at bss start */
    __bss_start__ = _sbss;
    *(.bss)
    *(.bss*)
    *(COMMON)

    . = ALIGN(4);
    _ebss = .;         /* define a global symbol at bss end */
    __bss_end__ = _ebss;
  } >RAM

  /* User_heap_stack section, used to check that there is enough RAM left */
  ._user_heap_stack :
  {
    . = ALIGN(8);
    PROVIDE ( end = . );
    PROVIDE ( _end = . );
    . = . + _Min_Heap_Size;
    . = . + _Min_Stack_Size;
    . = ALIGN(8);
  } >RAM

  __RAM_segment_used_end__ = .;

  /* Remove information from the standard libraries */
  /DISCARD/ :
  {
    libc.a ( * )
    libm.a ( * )
    libgcc.a ( * )
  }

  .ARM.attributes 0 : { *(.ARM.attributes) }
}

3.4、底层初始化文件`tx_initialize_low_level.S`修改

路径：threadx-6.2.1\ports\cortex_m7\gnu\src\tx_initialize_low_level.S

1、修改中断向量表标号
2、修改systick使用的系统时钟

至此，移植工作完成。

4、编写应用程序

1、在main.c中编写两个任务，然后在tx_application_define中创建这两个任务:

#include <stdio.h>
#include "tx_api.h"
#include "main.h"

#define THREAD1_PRIO         3
#define THREAD1_STACK_SIZE   1024
static  TX_THREAD thread1;
uint8_t thread1_stack[THREAD1_STACK_SIZE];

#define THREAD2_PRIO         2
#define THREAD2_STACK_SIZE   1024
static  TX_THREAD thread2;
uint8_t thread2_stack[THREAD2_STACK_SIZE];

void my_thread1_entry(ULONG thread_input)
{
  /* Enter into a forever loop. */
  while(1)
  {
    printf("threadx 1 application running...\r\n");
    /* Sleep for 1000 tick. */
    tx_thread_sleep(1000);
  }
}

void my_thread2_entry(ULONG thread_input)
{
  /* Enter into a forever loop. */
  while(1)
  {
    printf("threadx 2 application running...\r\n");
    /* Sleep for 1000 tick. */
    tx_thread_sleep(1000);
  }
}

void tx_application_define(void *first_unused_memory)
{
  /* Create thread */
  tx_thread_create(&thread1, "thread 1", my_thread1_entry, 0, &thread1_stack[0], THREAD1_STACK_SIZE, THREAD1_PRIO, THREAD1_PRIO, TX_NO_TIME_SLICE, TX_AUTO_START);
    
  tx_thread_create(&thread2, "thread 2", my_thread2_entry, 0, &thread2_stack[0], THREAD2_STACK_SIZE, THREAD2_PRIO, THREAD2_PRIO, TX_NO_TIME_SLICE, TX_AUTO_START);
}

2、在main()函数中启动threadx内核：

#include <stdio.h>
#include "tx_api.h"

void main(void)
{
	SystemClockConfig();

	UART_init(USART0, 115200, USART_WordLength_8b, USART_StopBits_1b, USART_Parity_No);

	tx_kernel_enter( );
}