硬件：JZ2440
实现功能：用putchr()函数实现printf()
start.s
nand.c
uart.c
uart.h
my_stdio.c
my_stdio.h
main.c
start.s源码：
.extern main .text .global _start _start: ldr sp,=4096 bl watchdog_init bl clock_init bl nand_init bl sdram_init ldr r0,=0x30000000 mov r1,#4096 mov r2,#(1024*16) bl nand_read ldr sp,=0x34000000 ldr lr,=main_return ldr pc,=main main_return: b main_return
init.c
//watchdog #define WTCON (*(volatile unsigned long *)0x53000000) //clock #define LOCKTIME (*(volatile unsigned long *)0x4c000000) #define MPLLCON (*(volatile unsigned long *)0x4c000004) #define CLKDIVN (*(volatile unsigned long *)0x4c000014) //sdram #define BWSCON (*(volatile unsigned long *)0x48000000) #define BANKCON0 (*(volatile unsigned long *)0x48000004) #define BANKCON1 (*(volatile unsigned long *)0x48000008) #define BANKCON2 (*(volatile unsigned long *)0x4800000c) #define BANKCON3 (*(volatile unsigned long *)0x48000010) #define BANKCON4 (*(volatile unsigned long *)0x48000014) #define BANKCON5 (*(volatile unsigned long *)0x48000018) #define BANKCON6 (*(volatile unsigned long *)0x4800001c) #define BANKCON7 (*(volatile unsigned long *)0x48000020) #define REFRESH (*(volatile unsigned long *)0x48000024) #define BANKSIZE (*(volatile unsigned long *)0x48000028) #define MRSRB6 (*(volatile unsigned long *)0x4800002c) #define MRSRB7 (*(volatile unsigned long *)0x48000030) void watchdog_init(void) { WTCON=0; } void clock_init(void) { CLKDIVN=0x03; __asm__ ( "mrc p15,0,r1,c1,c0,0 " "orr r1,r1,#0xc0000000 " "mcr p15,0,r1,c1,c0,0 " ); MPLLCON=((0x5c<<12)|(0x01<<4)|(0x02)); } void sdram_init(void) { volatile unsigned long *sdram_base=(volatile unsigned long *)0x48000000; sdram_base[0] = 0x22011110; sdram_base[1] = 0x00000700; sdram_base[2] = 0x00000700; sdram_base[3] = 0x00000700; sdram_base[4] = 0x00000700; sdram_base[5] = 0x00000700; sdram_base[6] = 0x00000700; sdram_base[7] = 0x00018005; sdram_base[8] = 0x00018005; sdram_base[9] = 0x008C04F4; sdram_base[10] = 0x000000B1; sdram_base[11] = 0x00000030; sdram_base[12] = 0x00000030; }
nand.c
#define LARGER_NAND_PAGE #define GSTATUS1 (*(volatile unsigned int *)0x560000B0) #define BUSY 1 #define NAND_SECTOR_SIZE 512 #define NAND_BLOCK_MASK (NAND_SECTOR_SIZE - 1) #define NAND_SECTOR_SIZE_LP 2048 #define NAND_BLOCK_MASK_LP (NAND_SECTOR_SIZE_LP - 1) typedef unsigned int S3C24X0_REG32; /* NAND FLASH (see S3C2410 manual chapter 6) */ typedef struct { S3C24X0_REG32 NFCONF; S3C24X0_REG32 NFCMD; S3C24X0_REG32 NFADDR; S3C24X0_REG32 NFDATA; S3C24X0_REG32 NFSTAT; S3C24X0_REG32 NFECC; } S3C2410_NAND; /* NAND FLASH (see S3C2440 manual chapter 6, www.100ask.net) */ typedef struct { S3C24X0_REG32 NFCONF; S3C24X0_REG32 NFCONT; S3C24X0_REG32 NFCMD; S3C24X0_REG32 NFADDR; S3C24X0_REG32 NFDATA; S3C24X0_REG32 NFMECCD0; S3C24X0_REG32 NFMECCD1; S3C24X0_REG32 NFSECCD; S3C24X0_REG32 NFSTAT; S3C24X0_REG32 NFESTAT0; S3C24X0_REG32 NFESTAT1; S3C24X0_REG32 NFMECC0; S3C24X0_REG32 NFMECC1; S3C24X0_REG32 NFSECC; S3C24X0_REG32 NFSBLK; S3C24X0_REG32 NFEBLK; } S3C2440_NAND; typedef struct { void (*nand_reset)(void); void (*wait_idle)(void); void (*nand_select_chip)(void); void (*nand_deselect_chip)(void); void (*write_cmd)(int cmd); void (*write_addr)(unsigned int addr); unsigned char (*read_data)(void); }t_nand_chip; static S3C2410_NAND * s3c2410nand = (S3C2410_NAND *)0x4e000000; static S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000; static t_nand_chip nand_chip; /* 供外部调用的函数 */ void nand_init(void); void nand_read(unsigned char *buf, unsigned long start_addr, int size); /* NAND Flash操作的总入口, 它们将调用S3C2410或S3C2440的相应函数 */ static void nand_reset(void); static void wait_idle(void); static void nand_select_chip(void); static void nand_deselect_chip(void); static void write_cmd(int cmd); static void write_addr(unsigned int addr); static unsigned char read_data(void); /* S3C2410的NAND Flash处理函数 */ static void s3c2410_nand_reset(void); static void s3c2410_wait_idle(void); static void s3c2410_nand_select_chip(void); static void s3c2410_nand_deselect_chip(void); static void s3c2410_write_cmd(int cmd); static void s3c2410_write_addr(unsigned int addr); static unsigned char s3c2410_read_data(); /* S3C2440的NAND Flash处理函数 */ static void s3c2440_nand_reset(void); static void s3c2440_wait_idle(void); static void s3c2440_nand_select_chip(void); static void s3c2440_nand_deselect_chip(void); static void s3c2440_write_cmd(int cmd); static void s3c2440_write_addr(unsigned int addr); static unsigned char s3c2440_read_data(void); /* S3C2410的NAND Flash操作函数 */ /* 复位 */ static void s3c2410_nand_reset(void) { s3c2410_nand_select_chip(); s3c2410_write_cmd(0xff); // 复位命令 s3c2410_wait_idle(); s3c2410_nand_deselect_chip(); } /* 等待NAND Flash就绪 */ static void s3c2410_wait_idle(void) { int i; volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFSTAT; while(!(*p & BUSY)) for(i=0; i<10; i++); } /* 发出片选信号 */ static void s3c2410_nand_select_chip(void) { int i; s3c2410nand->NFCONF &= ~(1<<11); for(i=0; i<10; i++); } /* 取消片选信号 */ static void s3c2410_nand_deselect_chip(void) { s3c2410nand->NFCONF |= (1<<11); } /* 发出命令 */ static void s3c2410_write_cmd(int cmd) { volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFCMD; *p = cmd; } /* 发出地址 */ static void s3c2410_write_addr(unsigned int addr) { int i; volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFADDR; *p = addr & 0xff; for(i=0; i<10; i++); *p = (addr >> 9) & 0xff; for(i=0; i<10; i++); *p = (addr >> 17) & 0xff; for(i=0; i<10; i++); *p = (addr >> 25) & 0xff; for(i=0; i<10; i++); } /* 读取数据 */ static unsigned char s3c2410_read_data(void) { volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFDATA; return *p; } /* S3C2440的NAND Flash操作函数 */ /* 复位 */ static void s3c2440_nand_reset(void) { s3c2440_nand_select_chip(); s3c2440_write_cmd(0xff); // 复位命令 s3c2440_wait_idle(); s3c2440_nand_deselect_chip(); } /* 等待NAND Flash就绪 */ static void s3c2440_wait_idle(void) { int i; volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFSTAT; while(!(*p & BUSY)) for(i=0; i<10; i++); } /* 发出片选信号 */ static void s3c2440_nand_select_chip(void) { int i; s3c2440nand->NFCONT &= ~(1<<1); for(i=0; i<10; i++); } /* 取消片选信号 */ static void s3c2440_nand_deselect_chip(void) { s3c2440nand->NFCONT |= (1<<1); } /* 发出命令 */ static void s3c2440_write_cmd(int cmd) { volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFCMD; *p = cmd; } /* 发出地址 */ static void s3c2440_write_addr(unsigned int addr) { int i; volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR; *p = addr & 0xff; for(i=0; i<10; i++); *p = (addr >> 9) & 0xff; for(i=0; i<10; i++); *p = (addr >> 17) & 0xff; for(i=0; i<10; i++); *p = (addr >> 25) & 0xff; for(i=0; i<10; i++); } static void s3c2440_write_addr_lp(unsigned int addr) { int i; volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR; int col, page; col = addr & NAND_BLOCK_MASK_LP; page = addr / NAND_SECTOR_SIZE_LP; *p = col & 0xff; /* Column Address A0~A7 */ for(i=0; i<10; i++); *p = (col >> 8) & 0x0f; /* Column Address A8~A11 */ for(i=0; i<10; i++); *p = page & 0xff; /* Row Address A12~A19 */ for(i=0; i<10; i++); *p = (page >> 8) & 0xff; /* Row Address A20~A27 */ for(i=0; i<10; i++); *p = (page >> 16) & 0x03; /* Row Address A28~A29 */ for(i=0; i<10; i++); } /* 读取数据 */ static unsigned char s3c2440_read_data(void) { volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFDATA; return *p; } /* 在第一次使用NAND Flash前，复位一下NAND Flash */ static void nand_reset(void) { nand_chip.nand_reset(); } static void wait_idle(void) { nand_chip.wait_idle(); } static void nand_select_chip(void) { int i; nand_chip.nand_select_chip(); for(i=0; i<10; i++); } static void nand_deselect_chip(void) { nand_chip.nand_deselect_chip(); } static void write_cmd(int cmd) { nand_chip.write_cmd(cmd); } static void write_addr(unsigned int addr) { nand_chip.write_addr(addr); } static unsigned char read_data(void) { return nand_chip.read_data(); } /* 初始化NAND Flash */ void nand_init(void) { #define TACLS 0 #define TWRPH0 3 #define TWRPH1 0 /* 判断是S3C2410还是S3C2440 */ if ((GSTATUS1 == 0x32410000) || (GSTATUS1 == 0x32410002)) { nand_chip.nand_reset = s3c2410_nand_reset; nand_chip.wait_idle = s3c2410_wait_idle; nand_chip.nand_select_chip = s3c2410_nand_select_chip; nand_chip.nand_deselect_chip = s3c2410_nand_deselect_chip; nand_chip.write_cmd = s3c2410_write_cmd; nand_chip.write_addr = s3c2410_write_addr; nand_chip.read_data = s3c2410_read_data; /* 使能NAND Flash控制器, 初始化ECC, 禁止片选, 设置时序 */ s3c2410nand->NFCONF = (1<<15)|(1<<12)|(1<<11)|(TACLS<<8)|(TWRPH0<<4)|(TWRPH1<<0); } else { nand_chip.nand_reset = s3c2440_nand_reset; nand_chip.wait_idle = s3c2440_wait_idle; nand_chip.nand_select_chip = s3c2440_nand_select_chip; nand_chip.nand_deselect_chip = s3c2440_nand_deselect_chip; nand_chip.write_cmd = s3c2440_write_cmd; #ifdef LARGER_NAND_PAGE nand_chip.write_addr = s3c2440_write_addr_lp; #else nand_chip.write_addr = s3c2440_write_addr; #endif nand_chip.read_data = s3c2440_read_data; /* 设置时序 */ s3c2440nand->NFCONF = (TACLS<<12)|(TWRPH0<<8)|(TWRPH1<<4); /* 使能NAND Flash控制器, 初始化ECC, 禁止片选 */ s3c2440nand->NFCONT = (1<<4)|(1<<1)|(1<<0); } /* 复位NAND Flash */ nand_reset(); } /* 读函数 */ void nand_read(unsigned char *buf, unsigned long start_addr, int size) { int i, j; #ifdef LARGER_NAND_PAGE if ((start_addr & NAND_BLOCK_MASK_LP) || (size & NAND_BLOCK_MASK_LP)) { return ; /* 地址或长度不对齐 */ } #else if ((start_addr & NAND_BLOCK_MASK) || (size & NAND_BLOCK_MASK)) { return ; /* 地址或长度不对齐 */ } #endif /* 选中芯片 */ nand_select_chip(); for(i=start_addr; i < (start_addr + size);) { /* 发出READ0命令 */ write_cmd(0); /* Write Address */ write_addr(i); #ifdef LARGER_NAND_PAGE write_cmd(0x30); #endif wait_idle(); #ifdef LARGER_NAND_PAGE for(j=0; j < NAND_SECTOR_SIZE_LP; j++, i++) { #else for(j=0; j < NAND_SECTOR_SIZE; j++, i++) { #endif *buf = read_data(); buf++; } } /* 取消片选信号 */ nand_deselect_chip(); return ; }
uart.c 源码：
#include"uart.h" //uart #define ULCON0 (*(volatile unsigned long *)0x50000000) #define UCON0 (*(volatile unsigned long *)0x50000004) #define UFCON0 (*(volatile unsigned long *)0x50000008) #define UMCON0 (*(volatile unsigned long *)0x5000000c) #define UTRSTAT0 (*(volatile unsigned long *)0x50000010) #define UERSTAT0 (*(volatile unsigned long *)0x50000014) #define UTXH0 (*(volatile unsigned char *)0x50000020) #define URXH0 (*(volatile unsigned char *)0x50000024) #define UBRDIV0 (*(volatile unsigned long *)0x50000028) //GPH #define GPHCON (*(volatile unsigned long *)0x56000070) #define GPHDAT (*(volatile unsigned long *)0x56000074) #define GPHUP (*(volatile unsigned long *)0x56000078) void uart0_init(void) { GPHCON|=0xa0; GPHUP=0x0c; ULCON0=0x03; UCON0=0x05; UFCON0=0x00; UMCON0=0x00; UBRDIV0=((50000000/(115200*16))-1); } unsigned char my_getchar(void) { while(!(UTRSTAT0 & 0x01)); return URXH0; } void my_putchar(unsigned char date) { while(!(UTRSTAT0 & 0x02)); UTXH0=date; } unsigned char getc(void) { while(!(UTRSTAT0 & 0x01)); return URXH0; } void putc(unsigned char c) { while(!(UTRSTAT0 & 0x02)); UTXH0=c; }
uart.h 源码：
#ifndef _UART_H_ #define _UART_H_ void uart0_init(void); unsigned char my_getchar(void); void my_putchar(unsigned char date); unsigned char getc(void); void putc(unsigned char c); #endif
my_stdio.c 源码：
#include"uart.h" #include"my_stdio.h" typedef char* va_list; #define int_sizeof(type) ((sizeof(int)+sizeof(type)-1)&~(sizeof(int)-1)) #define va_start(para_p,first_para) (para_p=(va_list)&first_para+int_sizeof(first_para)) #define va_arg(para_p,type) (*(type *)((para_p+=int_sizeof(type))-int_sizeof(type))) #define va_end(para_p) (para_p=(va_list)0) void my_printf(const char *format, ...) { va_list temp ; char *string = format; va_start(temp, format); while (*string) { if (*string == '%') { switch (*++string) { case 'c': { my_putchar(va_arg(temp,char)); break; } case 's': { char* p = va_arg(temp,char*); while (*p != 0) my_putchar(*p++); break; } case 'p': { unsigned int addr = (unsigned int)&va_arg(temp, unsigned int), sheft = 0xf0000000; unsigned char temp = 0,count=0; my_putchar('0'); my_putchar('x'); while (count<32) { temp = (unsigned char)(((sheft >> count)&addr) >> (32 - count - 4)) ; if (temp < 10) my_putchar(temp + 48); if (temp >= 10) my_putchar(temp+65-10); count += 4; } break; } case 'd': { int value = va_arg(temp, int),num=100000000; if (value == 0) my_putchar(48); if (value & 0x80000000) //负数 { my_putchar('-'); num = -10000000; } else //正数.; while (!(value / num)) { num /= 10; if (num == 0) { my_putchar(0); return; } } while (num != 0) { my_putchar(value / num+48); value %= num; num /= 10; } break; } case 'f': { char *str = "Sorry: function is not available"; while (*str != 0) my_putchar(*str++); } default: break; } } string++; } va_end(temp); }
my_stdio.h 源码：
#ifndef _OWN_STDIO_H_ #define _OWN_STDIO_H_ void my_printf(const char *format,...); #endif
main.c 源码：
#include"uart.h" #include"my_stdio.h" #include"stdio.h" void raise(int sig_nr){;} int main(void) { uart0_init(); printf("%s"," wds_standard "); my_printf("%s"," zsy_standard "); while(1) my_putchar(my_getchar()+1); return 0; }
链接脚本 uart.lds ：
SECTIONS { . = 0x00000000; .init : AT(0){start.o init.o nand.o} . = 0x30000000; .text : AT(4096){*(.text)} .rodata ALIGN(4) : AT((LOADADDR(.text)+SIZEOF(.text)+3)&~(0x03)) {*(.rodata*)} .data ALIGN(4) : AT((LOADADDR(.rodata)+SIZEOF(.rodata)+3)&~(0x03)) {*(.data)} .bss : {*(.bss) *(COMMON)} }
Makefile:
objs:= start.o init.o uart.o nand.o main.o my_stdio.o lib/libc.a CC =arm-linux-gcc LD =arm-linux-ld AR =arm-linux-ar OBJCOPY =arm-linux-objcopy OBJDUMP =arm-linux-objdump INCLUDEDIR :=$(shell pwd)/include CFLAGS :=-Wall -O2 CPPFLAGS :=-nostdinc -I$(INCLUDEDIR) export CC LD OBJCOPY OBJDUMP INCLUDEDIR CFLAGS CPPFLAGS uart.bin:$(objs) arm-linux-ld -Tuart.lds -o uart_elf $^ libgcc.a arm-linux-objcopy -O binary -S uart_elf $@ arm-linux-objdump -D -m arm uart_elf > uart.dis .PHONY:lib/libc.a lib/libc.a: cd lib;make;cd .. %.o:%.s $(CC) $(CPPFLAGS) $(FLAGS)-o $@ -c $< %.o:%.c $(CC) $(CPPFLAGS) $(FLAGS) -o $@ -c $< clean: make clean -C lib rm -f *.o *.bin *.dis uart_elf