目录
0. 环境准备
1. 安装交叉编译器
2. 理解makefile工作机理
3. 熟悉示例程序的代码结构，理解软核代码的底层驱动原理
4. 熟悉烧录环节的工作机理， 建立下载环境
5. 编写例子blink， printf等， 加载运行
6. 后续任务
0. 环境准备
NANO 9K低成本体验FPGA开发，还是挺香的，官方例子有加载PICORV32软核的例子，可以建立简单的ISP编程环境，通过串口就可以加载程序，很方便。
Tang Nano 9K picoRV 简单示例 - Sipeed Wiki
运行效果
可以通过命令行进行点灯喝运行benchmark等操作。
相当于例子包括了：
- 串口打印，
- 串口接收指令
- GPIO控制
等基本操作。
如果要基于RISCV软核，进一步熟悉工作机制和编程环境，需要参考例子建立交叉编译环境。
step by step.......，以下基于虚拟机运行ubuntu18.04环境，少一点干扰。
为帮助理解， 可以看看高云的官方文档对于picorv32内核架构的介绍：
1. 安装交叉编译器
在虚拟机环境下，解压toolchain到目标目录即可。编译器路径可以在makefile文件里进行指定。
当然，虚拟机依赖环境至少需要安装make工具,gcc也一起
sudo apt-get install make gcc
下载地址：
riscv32交叉编译器，ubuntu18.04亲测可用资源-CSDN文库
2. 理解makefile工作机理
参考文章：
从零开始：一步步教你如何写Makefile_makefile菜鸟教程-CSDN博客
makefile组成三要素：目标，依赖， 命令
picotiny工作示例里有两层makefile， 先看主目录下的：
PYTHON_NAME ?= python
RISCV_NAME ?= riscv-none-embed
RISCV_PATH ?= /home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004
MAKE ?= make
FW_FILE = fw/fw-flash/build/fw-flash.v
PROG_FILE ?= $(FW_FILE)
COMx ?= COM14
export PYTHON_NAME
export RISCV_NAME
export RISCV_PATH
.PHONY: all brom flash clean program
all: brom flash
$(FW_FILE): flash
brom:
$(MAKE) -C fw/fw-brom
flash:
$(MAKE) -C fw/fw-flash
clean:
$(MAKE) -C fw/fw-brom clean
$(MAKE) -C fw/fw-flash clean
program: $(PROG_FILE)
$(PYTHON_NAME) sw/pico-programmer.py $(PROG_FILE) $(COMx)第一部分：指定环境变量
第二部分：指定分支
第三部分：分支命令编写
这个根目录下的makefile主要功能：一是执行不同的子目录下 ，二是program命令分支。
真正编译项目代码的makefile是在子目录下。
再来看子目录下的makefile
PROJ_NAME=blink-flash
DEBUG=no
BENCH=no
MULDIV=no
COMPRESSED=no
SRCS = $(wildcard *.c) \
$(wildcard *.S)
LDSCRIPT = ./linker_flash.ld
RISCV_NAME ?= riscv-none-embed
RISCV_PATH ?= /home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004
MABI=ilp32
MARCH := rv32i
ifeq ($(MULDIV),yes)
MARCH := $(MARCH)m
endif
ifeq ($(COMPRESSED),yes)
MARCH := $(MARCH)ac
endif
CFLAGS += -march=$(MARCH) -mabi=$(MABI) -ffunction-sections -fdata-sections
LDFLAGS += -march=$(MARCH) -mabi=$(MABI) -Wl,--gc-sections
ifeq ($(DEBUG),yes)
CFLAGS += -g3 -O0
endif
ifeq ($(DEBUG),no)
CFLAGS += -g -O3
endif
ifeq ($(BENCH),yes)
CFLAGS += -fno-inline
endif
RISCV_CLIB=$(RISCV_PATH)/$(RISCV_NAME)/lib/$(MARCH)/$(MABI)/
RISCV_OBJCOPY = $(RISCV_PATH)/bin/$(RISCV_NAME)-objcopy
RISCV_OBJDUMP = $(RISCV_PATH)/bin/$(RISCV_NAME)-objdump
RISCV_CC = $(RISCV_PATH)/bin/$(RISCV_NAME)-gcc
CFLAGS += -MD -fstrict-volatile-bitfields
LDFLAGS += -nostdlib -lgcc -mcmodel=medany -nostartfiles -ffreestanding -Wl,-Bstatic,-T,$(LDSCRIPT),-Map,$(OBJDIR)/$(PROJ_NAME).map,--print-memory-usage
OBJDIR = build
OBJS := $(SRCS)
OBJS := $(OBJS:.c=.o)
OBJS := $(OBJS:.cpp=.o)
OBJS := $(OBJS:.S=.o)
OBJS := $(addprefix $(OBJDIR)/,$(OBJS))
SUBOBJ := $(addprefix $(OBJDIR)/,$(SUBDIRS))
SUBOBJ := $(addsuffix /*.o,$(SUBOBJ))
export RISCV_CC CFLAGS LDFLAGS OBJDIR
all: $(SUBDIRS) $(OBJDIR)/$(PROJ_NAME).elf $(OBJDIR)/$(PROJ_NAME).hex $(OBJDIR)/$(PROJ_NAME).asm $(OBJDIR)/$(PROJ_NAME).v
$(SUBDIRS): ECHO
make -C $@
ECHO:
@echo $(SUBDIRS)
$(OBJDIR)/%.elf: $(OBJS) | $(OBJDIR)
$(RISCV_CC) $(CFLAGS) -o $@ $^ $(SUBOBJ) $(LDFLAGS) $(LIBS)
%.hex: %.elf
$(RISCV_OBJCOPY) -O ihex $^ $@
%.bin: %.elf
$(RISCV_OBJCOPY) -O binary $^ $@
%.v: %.elf
$(RISCV_OBJCOPY) -O verilog $^ $@
%.asm: %.elf
$(RISCV_OBJDUMP) -S -d $^ > $@
$(OBJDIR)/%.o: %.c
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.cpp
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.S
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) -o $@ $^ -D__ASSEMBLY__=1
$(OBJDIR):
mkdir -p $@
clean:
rm -f $(OBJDIR)/$(PROJ_NAME).elf
rm -f $(OBJDIR)/$(PROJ_NAME).hex
rm -f $(OBJDIR)/$(PROJ_NAME).map
rm -f $(OBJDIR)/$(PROJ_NAME).v
rm -f $(OBJDIR)/$(PROJ_NAME).asm
find $(OBJDIR) -type f -name '*.d' -print0 | xargs -0 -r rm
find $(OBJDIR) -type f -name '*.o' -print0 | xargs -0 -r rm
.SECONDARY: $(OBJS)
主要完成的工作： 指定了环境变量，编译输出目标文件，编译后的处理（文件转换等） 。
编写完示例代码后，可以在子目录下运行make命令，执行响应的makefile即可完成目标代码编译。
3. 熟悉示例程序的代码结构，理解软核代码的底层驱动原理
4. 熟悉烧录环节的工作机理， 建立下载环境
烧录的riscv软核支持ISP（串口在线烧录）功能。 所以make program xxx命令调用的python脚本主要是握手协议和烧录固件的传输。
简单理解： 软核的ISP功能完成了flash固件的调用启动和程序引导运行工作。
小知识： 理解ISP
ISP的全称是：In System Programming，即在系统编程，该操作是通过MCU厂商出厂BootLoader来实现，通过ISP可以对主flash区域进行擦除、编程操作，还可以修改芯片的选项字节等。
ISP的实现逻辑是出厂“芯片”（我们这里是软核）自带了BootLoader程序，即出厂引导程序，通过BootLoader可以将程序从串口（上位机）下载到Flash中，实际的时序是通过RST来区分正常启动还是烧录状态，然后上位机的烧录脚本来控制串口时序， 用户程序实际上是通过串口最终下载到了FLASH中，然后程序从flash启动。
5. 编写例子blink， printf等， 加载运行
1)点灯--blink
blink主要是调用GPIO寄存器写入功能
#include <stdint.h>
#include <stdbool.h>
// a pointer to this is a null pointer, but the compiler does not
// know that because "sram" is a linker symbol from sections.lds.
extern uint32_t sram;
typedef struct {
volatile uint32_t OUT;
volatile uint32_t IN;
volatile uint32_t OE;
} PICOGPIO;
// 寄存器地址
#define GPIO0 ((PICOGPIO*)0x82000000)
#define FLASHIO_ENTRY_ADDR ((void *)0x80000054)
volatile int i;
// --------------------------------------------------------
void main()
{
GPIO0->OE = 0x3F;
GPIO0->OUT = 0x3F;
while (1)
{
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x01;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x02;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x04;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x08;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x10;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x20;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x00;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F;
for ( i = 0 ; i < 10000; i++);
}
}
void irqCallback() {
}makefile，其实之修改了PROJ_NAME
PROJ_NAME=blink-demo
DEBUG=no
BENCH=no
MULDIV=no
COMPRESSED=no
SRCS = $(wildcard *.c) \
$(wildcard *.S)
LDSCRIPT = ./linker_flash.ld
RISCV_NAME ?= riscv-none-embed
RISCV_PATH ?= /home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004
MABI=ilp32
MARCH := rv32i
ifeq ($(MULDIV),yes)
MARCH := $(MARCH)m
endif
ifeq ($(COMPRESSED),yes)
MARCH := $(MARCH)ac
endif
CFLAGS += -march=$(MARCH) -mabi=$(MABI) -ffunction-sections -fdata-sections
LDFLAGS += -march=$(MARCH) -mabi=$(MABI) -Wl,--gc-sections
ifeq ($(DEBUG),yes)
CFLAGS += -g3 -O0
endif
ifeq ($(DEBUG),no)
CFLAGS += -g -O3
endif
ifeq ($(BENCH),yes)
CFLAGS += -fno-inline
endif
RISCV_CLIB=$(RISCV_PATH)/$(RISCV_NAME)/lib/$(MARCH)/$(MABI)/
RISCV_OBJCOPY = $(RISCV_PATH)/bin/$(RISCV_NAME)-objcopy
RISCV_OBJDUMP = $(RISCV_PATH)/bin/$(RISCV_NAME)-objdump
RISCV_CC = $(RISCV_PATH)/bin/$(RISCV_NAME)-gcc
CFLAGS += -MD -fstrict-volatile-bitfields
LDFLAGS += -nostdlib -lgcc -mcmodel=medany -nostartfiles -ffreestanding -Wl,-Bstatic,-T,$(LDSCRIPT),-Map,$(OBJDIR)/$(PROJ_NAME).map,--print-memory-usage
OBJDIR = build
OBJS := $(SRCS)
OBJS := $(OBJS:.c=.o)
OBJS := $(OBJS:.cpp=.o)
OBJS := $(OBJS:.S=.o)
OBJS := $(addprefix $(OBJDIR)/,$(OBJS))
SUBOBJ := $(addprefix $(OBJDIR)/,$(SUBDIRS))
SUBOBJ := $(addsuffix /*.o,$(SUBOBJ))
export RISCV_CC CFLAGS LDFLAGS OBJDIR
all: $(SUBDIRS) $(OBJDIR)/$(PROJ_NAME).elf $(OBJDIR)/$(PROJ_NAME).hex $(OBJDIR)/$(PROJ_NAME).asm $(OBJDIR)/$(PROJ_NAME).v
$(SUBDIRS): ECHO
make -C $@
ECHO:
@echo $(SUBDIRS)
$(OBJDIR)/%.elf: $(OBJS) | $(OBJDIR)
$(RISCV_CC) $(CFLAGS) -o $@ $^ $(SUBOBJ) $(LDFLAGS) $(LIBS)
%.hex: %.elf
$(RISCV_OBJCOPY) -O ihex $^ $@
%.bin: %.elf
$(RISCV_OBJCOPY) -O binary $^ $@
%.v: %.elf
$(RISCV_OBJCOPY) -O verilog $^ $@
%.asm: %.elf
$(RISCV_OBJDUMP) -S -d $^ > $@
$(OBJDIR)/%.o: %.c
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.cpp
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.S
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) -o $@ $^ -D__ASSEMBLY__=1
$(OBJDIR):
mkdir -p $@
clean:
rm -f $(OBJDIR)/$(PROJ_NAME).elf
rm -f $(OBJDIR)/$(PROJ_NAME).hex
rm -f $(OBJDIR)/$(PROJ_NAME).map
rm -f $(OBJDIR)/$(PROJ_NAME).v
rm -f $(OBJDIR)/$(PROJ_NAME).asm
find $(OBJDIR) -type f -name '*.d' -print0 | xargs -0 -r rm
find $(OBJDIR) -type f -name '*.o' -print0 | xargs -0 -r rm
.SECONDARY: $(OBJS)
项目目录下编译：
/blink-demo$ make
mkdir -p build/
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-gcc -c -march=rv32i -mabi=ilp32 -ffunction-sections -fdata-sections -g -O3 -MD -fstrict-volatile-bitfields -o build/main.o main.c
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-gcc -march=rv32i -mabi=ilp32 -ffunction-sections -fdata-sections -g -O3 -MD -fstrict-volatile-bitfields -o build/blink-demo.elf build/main.o build/crt_flash.o -march=rv32i -mabi=ilp32 -Wl,--gc-sections -nostdlib -lgcc -mcmodel=medany -nostartfiles -ffreestanding -Wl,-Bstatic,-T,./linker_flash.ld,-Map,build/blink-demo.map,--print-memory-usage
Memory region Used Size Region Size %age Used
FLASH: 728 B 8 MB 0.01%
RAM: 1040 B 8 KB 12.70%
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objcopy -O ihex build/blink-demo.elf build/blink-demo.hex
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objdump -S -d build/blink-demo.elf > build/blink-demo.asm
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objcopy -O verilog build/blink-demo.elf build/blink-demo.v生成的.v文件即用于执行的文件。
执行根目录下的make program来烧录
烧录成功：
...../picotiny$ make programBlink
python sw/pico-programmer.py fw/blink-demo/build/blink-demo.v /dev/ttyUSB1
Read program with 736 bytes
- Waiting for reset -
...
Total sectors 1
Total pages 3
Flashing 1 / 1
Flashing completedRISCV例程执行--blink-CSDN直播
2)单独编写串口交互：
main.c:
#include <stdint.h>
#include <stdbool.h>
// a pointer to this is a null pointer, but the compiler does not
// know that because "sram" is a linker symbol from sections.lds.
extern uint32_t sram;
typedef struct {
volatile uint32_t DATA;
volatile uint32_t CLKDIV;
} PICOUART;
typedef struct {
volatile uint32_t OUT;
volatile uint32_t IN;
volatile uint32_t OE;
} PICOGPIO;
typedef struct {
union {
volatile uint32_t REG;
volatile uint16_t IOW;
struct {
volatile uint8_t IO;
volatile uint8_t OE;
volatile uint8_t CFG;
volatile uint8_t EN;
};
};
} PICOQSPI;
#define QSPI0 ((PICOQSPI*)0x81000000)
#define GPIO0 ((PICOGPIO*)0x82000000)
#define UART0 ((PICOUART*)0x83000000)
#define FLASHIO_ENTRY_ADDR ((void *)0x80000054)
void (*spi_flashio)(uint8_t *pdata, int length, int wren) = FLASHIO_ENTRY_ADDR;
int putchar(int c)
{
if (c == '\n')
UART0->DATA = '\r';
UART0->DATA = c;
return c;
}
void print(const char *p)
{
while (*p)
putchar(*(p++));
}
void print_hex(uint32_t v, int digits)
{
for (int i = 7; i >= 0; i--) {
char c = "0123456789abcdef"[(v >> (4*i)) & 15];
if (c == '0' && i >= digits) continue;
putchar(c);
digits = i;
}
}
void print_dec(uint32_t v)
{
if (v >= 100) {
print(">=100");
return;
}
if (v >= 90) { putchar('9'); v -= 90; }
else if (v >= 80) { putchar('8'); v -= 80; }
else if (v >= 70) { putchar('7'); v -= 70; }
else if (v >= 60) { putchar('6'); v -= 60; }
else if (v >= 50) { putchar('5'); v -= 50; }
else if (v >= 40) { putchar('4'); v -= 40; }
else if (v >= 30) { putchar('3'); v -= 30; }
else if (v >= 20) { putchar('2'); v -= 20; }
else if (v >= 10) { putchar('1'); v -= 10; }
if (v >= 9) { putchar('9'); v -= 9; }
else if (v >= 8) { putchar('8'); v -= 8; }
else if (v >= 7) { putchar('7'); v -= 7; }
else if (v >= 6) { putchar('6'); v -= 6; }
else if (v >= 5) { putchar('5'); v -= 5; }
else if (v >= 4) { putchar('4'); v -= 4; }
else if (v >= 3) { putchar('3'); v -= 3; }
else if (v >= 2) { putchar('2'); v -= 2; }
else if (v >= 1) { putchar('1'); v -= 1; }
else putchar('0');
}
char getchar_prompt(char *prompt)
{
int32_t c = -1;
uint32_t cycles_begin, cycles_now, cycles;
__asm__ volatile ("rdcycle %0" : "=r"(cycles_begin));
if (prompt)
print(prompt);
// if (prompt)
// GPIO0->OUT = ~0;
// reg_leds = ~0;
while (c == -1) {
__asm__ volatile ("rdcycle %0" : "=r"(cycles_now));
cycles = cycles_now - cycles_begin;
if (cycles > 12000000) {
if (prompt)
print(prompt);
cycles_begin = cycles_now;
// if (prompt)
// GPIO0->OUT = ~GPIO0->OUT;
// reg_leds = ~reg_leds;
}
c = UART0->DATA;
}
// if (prompt)
// GPIO0->OUT = 0;
// reg_leds = 0;
return c;
}
char getchar()
{
return getchar_prompt(0);
}
#define QSPI_REG_CRM 0x00100000
#define QSPI_REG_DSPI 0x00400000
void cmd_set_crm(int on)
{
if (on) {
QSPI0->REG |= QSPI_REG_CRM;
} else {
QSPI0->REG &= ~QSPI_REG_CRM;
}
}
int cmd_get_crm() {
return QSPI0->REG & QSPI_REG_CRM;
}
volatile int i;
// --------------------------------------------------------
#define CLK_FREQ 25175000
#define UART_BAUD 115200
void main()
{
UART0->CLKDIV = CLK_FREQ / UART_BAUD - 2;
GPIO0->OE = 0x3F;
GPIO0->OUT = 0x3F;
cmd_set_crm(1);
print("\n");
print(" ____ _ ____ ____\n");
print(" | _ \\(_) ___ ___/ ___| ___ / ___|\n");
print(" | |_) | |/ __/ _ \\___ \\ / _ \\| |\n");
print(" | __/| | (_| (_) |__) | (_) | |___\n");
print(" |_| |_|\\___\\___/____/ \\___/ \\____|\n");
print("\n");
print(" On Lichee Tang Nano-9K\n");
print("\n");
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x01;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x02;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x04;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x08;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x10;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F ^ 0x20;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x00;
for ( i = 0 ; i < 10000; i++);
GPIO0->OUT = 0x3F;
for ( i = 0 ; i < 10000; i++);
while (1)
{
print("\n");
print("Select an action:\n");
print("\n");
print(" [1] Toggle led 1\n");
print(" [2] Toggle led 2\n");
print(" [3] Toggle led 3\n");
print(" [4] Toggle led 4\n");
print(" [5] Toggle led 5\n");
print(" [6] Toggle led 6\n");
for (int rep = 10; rep > 0; rep--)
{
print("\n");
print("IO State: ");
print_hex(GPIO0->IN, 8);
print("\n");
print("\n");
print("Command> ");
char cmd = getchar();
if (cmd > 32 && cmd < 127)
putchar(cmd);
print("\n");
switch (cmd)
{
case '1':
GPIO0->OUT ^= 0x00000001;
break;
case '2':
GPIO0->OUT ^= 0x00000002;
break;
case '3':
GPIO0->OUT ^= 0x00000004;
break;
case '4':
GPIO0->OUT ^= 0x00000008;
break;
case '5':
GPIO0->OUT ^= 0x00000010;
break;
case '6':
GPIO0->OUT ^= 0x00000020;
break;
default:
continue;
}
}
}
}
void irqCallback() {
}makefile:
PROJ_NAME=uart-demo
DEBUG=no
BENCH=no
MULDIV=no
COMPRESSED=no
SRCS = $(wildcard *.c) \
$(wildcard *.S)
LDSCRIPT = ./linker_flash.ld
RISCV_NAME ?= riscv-none-embed
RISCV_PATH ?= /home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004
MABI=ilp32
MARCH := rv32i
ifeq ($(MULDIV),yes)
MARCH := $(MARCH)m
endif
ifeq ($(COMPRESSED),yes)
MARCH := $(MARCH)ac
endif
CFLAGS += -march=$(MARCH) -mabi=$(MABI) -ffunction-sections -fdata-sections
LDFLAGS += -march=$(MARCH) -mabi=$(MABI) -Wl,--gc-sections
ifeq ($(DEBUG),yes)
CFLAGS += -g3 -O0
endif
ifeq ($(DEBUG),no)
CFLAGS += -g -O3
endif
ifeq ($(BENCH),yes)
CFLAGS += -fno-inline
endif
RISCV_CLIB=$(RISCV_PATH)/$(RISCV_NAME)/lib/$(MARCH)/$(MABI)/
RISCV_OBJCOPY = $(RISCV_PATH)/bin/$(RISCV_NAME)-objcopy
RISCV_OBJDUMP = $(RISCV_PATH)/bin/$(RISCV_NAME)-objdump
RISCV_CC = $(RISCV_PATH)/bin/$(RISCV_NAME)-gcc
CFLAGS += -MD -fstrict-volatile-bitfields
LDFLAGS += -nostdlib -lgcc -mcmodel=medany -nostartfiles -ffreestanding -Wl,-Bstatic,-T,$(LDSCRIPT),-Map,$(OBJDIR)/$(PROJ_NAME).map,--print-memory-usage
OBJDIR = build
OBJS := $(SRCS)
OBJS := $(OBJS:.c=.o)
OBJS := $(OBJS:.cpp=.o)
OBJS := $(OBJS:.S=.o)
OBJS := $(addprefix $(OBJDIR)/,$(OBJS))
SUBOBJ := $(addprefix $(OBJDIR)/,$(SUBDIRS))
SUBOBJ := $(addsuffix /*.o,$(SUBOBJ))
export RISCV_CC CFLAGS LDFLAGS OBJDIR
all: $(SUBDIRS) $(OBJDIR)/$(PROJ_NAME).elf $(OBJDIR)/$(PROJ_NAME).hex $(OBJDIR)/$(PROJ_NAME).asm $(OBJDIR)/$(PROJ_NAME).v
$(SUBDIRS): ECHO
make -C $@
ECHO:
@echo $(SUBDIRS)
$(OBJDIR)/%.elf: $(OBJS) | $(OBJDIR)
$(RISCV_CC) $(CFLAGS) -o $@ $^ $(SUBOBJ) $(LDFLAGS) $(LIBS)
%.hex: %.elf
$(RISCV_OBJCOPY) -O ihex $^ $@
%.bin: %.elf
$(RISCV_OBJCOPY) -O binary $^ $@
%.v: %.elf
$(RISCV_OBJCOPY) -O verilog $^ $@
%.asm: %.elf
$(RISCV_OBJDUMP) -S -d $^ > $@
$(OBJDIR)/%.o: %.c
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.cpp
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) $(INC) -o $@ $^
$(OBJDIR)/%.o: %.S
mkdir -p $(dir $@)
$(RISCV_CC) -c $(CFLAGS) -o $@ $^ -D__ASSEMBLY__=1
$(OBJDIR):
mkdir -p $@
clean:
rm -f $(OBJDIR)/$(PROJ_NAME).elf
rm -f $(OBJDIR)/$(PROJ_NAME).hex
rm -f $(OBJDIR)/$(PROJ_NAME).map
rm -f $(OBJDIR)/$(PROJ_NAME).v
rm -f $(OBJDIR)/$(PROJ_NAME).asm
find $(OBJDIR) -type f -name '*.d' -print0 | xargs -0 -r rm
find $(OBJDIR) -type f -name '*.o' -print0 | xargs -0 -r rm
.SECONDARY: $(OBJS)
项目子目录下编译结果，生成目标文件：
/uart-demo$ make
mkdir -p build/
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-gcc -c -march=rv32i -mabi=ilp32 -ffunction-sections -fdata-sections -g -O3 -MD -fstrict-volatile-bitfields -o build/main.o main.c
mkdir -p build/
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-gcc -c -march=rv32i -mabi=ilp32 -ffunction-sections -fdata-sections -g -O3 -MD -fstrict-volatile-bitfields -o build/crt_flash.o crt_flash.S -D__ASSEMBLY__=1
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-gcc -march=rv32i -mabi=ilp32 -ffunction-sections -fdata-sections -g -O3 -MD -fstrict-volatile-bitfields -o build/uart-demo.elf build/main.o build/crt_flash.o -march=rv32i -mabi=ilp32 -Wl,--gc-sections -nostdlib -lgcc -mcmodel=medany -nostartfiles -ffreestanding -Wl,-Bstatic,-T,./linker_flash.ld,-Map,build/uart-demo.map,--print-memory-usage
Memory region Used Size Region Size %age Used
FLASH: 3152 B 8 MB 0.04%
RAM: 1040 B 8 KB 12.70%
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objcopy -O ihex build/uart-demo.elf build/uart-demo.hex
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objdump -S -d build/uart-demo.elf > build/uart-demo.asm
/home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004/bin/riscv-none-embed-objcopy -O verilog build/uart-demo.elf build/uart-demo.v根目录下烧录运行：
makefile增加选项programUart：
PYTHON_NAME ?= python
RISCV_NAME ?= riscv-none-embed
RISCV_PATH ?= /home/hy/riscv/gnu-mcu-eclipse/riscv-none-gcc/8.2.0-2.2-20190521-0004
MAKE ?= make
FW_FILE_BLINK = fw/blink-demo/build/blink-demo.v
FW_FILE_UART = fw/uart-demo/build/uart-demo.v
PROG_FILE_BLINK ?= $(FW_FILE_BLINK)
PROG_FILE_UART ?= $(FW_FILE_UART)
COMx ?= /dev/ttyUSB1
export PYTHON_NAME
export RISCV_NAME
export RISCV_PATH
.PHONY: all brom flash clean program
all: brom flash
$(FW_FILE): flash
brom:
$(MAKE) -C fw/fw-brom
flash:
$(MAKE) -C fw/blink-demo
clean:
$(MAKE) -C fw/fw-brom clean
$(MAKE) -C fw/fw-flash clean
program: $(PROG_FILE)
$(PYTHON_NAME) sw/pico-programmer.py $(PROG_FILE) $(COMx)
programBlink: $(PROG_FILE_BLINK)
$(PYTHON_NAME) sw/pico-programmer.py $(PROG_FILE_BLINK) $(COMx)
programUart: $(PROG_FILE_UART)
$(PYTHON_NAME) sw/pico-programmer.py $(PROG_FILE_UART) $(COMx)
运行烧录：
/picotiny$ make programUart
python sw/pico-programmer.py fw/uart-demo/build/uart-demo.v /dev/ttyUSB1
Read program with 3152 bytes
- Waiting for reset -
..
Total sectors 1
Total pages 13
Flashing 1 / 1
Flashing completed调用cutecom运行页面：
输入框输入1-6可以控制对应的LED亮灭。
6. 后续任务
1）延申理解，通过官方开发包，编写更易于移植和开发的库
2）理解配合软核的SDK架构（理解指令集） 和HAL库的基本逻辑。 理解SDK应该按什么逻辑来规划
3）移植FREERTOS， 理解操作系统移植的基本逻辑
