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：

  1. .extern main
  2. .text
  3. .global _start
  4. _start:
  5.       ldr sp,=
  6.       bl  watchdog_init
  7.       bl  clock_init
  8.       bl  nand_init
  9.       bl  sdram_init 
  10.  
  11.       ldr r0,=0x30000000
  12.       mov r1,#
  13.       mov r2,#(*)
  14.       bl  nand_read
  15.  
  16.       ldr sp,=0x34000000
  17.       ldr lr,=main_return
  18.       ldr pc,=main
  19. main_return:
  20.       b main_return
  21.

init.c

  1. //watchdog
  2. #define WTCON      (*(volatile unsigned long *)0x53000000)
  3.  
  4. //clock
  5. #define LOCKTIME   (*(volatile unsigned long *)0x4c000000)
  6. #define MPLLCON    (*(volatile unsigned long *)0x4c000004)
  7. #define CLKDIVN    (*(volatile unsigned long *)0x4c000014)
  8.  
  9. //sdram
  10. #define BWSCON     (*(volatile unsigned long *)0x48000000)
  11. #define BANKCON0   (*(volatile unsigned long *)0x48000004)
  12. #define BANKCON1   (*(volatile unsigned long *)0x48000008)
  13. #define BANKCON2   (*(volatile unsigned long *)0x4800000c)
  14. #define BANKCON3   (*(volatile unsigned long *)0x48000010)
  15. #define BANKCON4   (*(volatile unsigned long *)0x48000014)
  16. #define BANKCON5   (*(volatile unsigned long *)0x48000018)
  17. #define BANKCON6   (*(volatile unsigned long *)0x4800001c)
  18. #define BANKCON7   (*(volatile unsigned long *)0x48000020)
  19. #define REFRESH    (*(volatile unsigned long *)0x48000024)
  20. #define BANKSIZE   (*(volatile unsigned long *)0x48000028)
  21. #define MRSRB6     (*(volatile unsigned long *)0x4800002c)
  22. #define MRSRB7     (*(volatile unsigned long *)0x48000030)
  23.  
  24. void watchdog_init(void)
  25. {
  26.     WTCON=;
  27. }
  28.  
  29. void clock_init(void)
  30. {
  31.     CLKDIVN=0x03;
  32.     __asm__
  33.     (
  34.     "mrc p15,0,r1,c1,c0,0\n"
  35.     "orr r1,r1,#0xc0000000\n"
  36.     "mcr p15,0,r1,c1,c0,0\n"
  37.     );
  38.        MPLLCON=((0x5c<<)|(0x01<<)|(0x02));
  39. }
  40.  
  41. void sdram_init(void)
  42. {
  43.     volatile unsigned long *sdram_base=(volatile unsigned long *)0x48000000;
  44.     sdram_base[]  = 0x22011110;
  45.     sdram_base[]  = 0x00000700;
  46.     sdram_base[]  = 0x00000700;
  47.     sdram_base[]  = 0x00000700;
  48.     sdram_base[]  = 0x00000700;
  49.     sdram_base[]  = 0x00000700;
  50.     sdram_base[]  = 0x00000700;
  51.     sdram_base[]  = 0x00018005;
  52.     sdram_base[]  = 0x00018005;
  53.     sdram_base[]  = 0x008C04F4;
  54.     sdram_base[] = 0x000000B1;
  55.     sdram_base[] = 0x00000030;
  56.     sdram_base[] = 0x00000030;     
  57.  
  58. }

nand.c

  1. #define LARGER_NAND_PAGE
  2.  
  3. #define GSTATUS1        (*(volatile unsigned int *)0x560000B0)
  4. #define BUSY            1
  5.  
  6. #define NAND_SECTOR_SIZE    512
  7. #define NAND_BLOCK_MASK     (NAND_SECTOR_SIZE - 1)
  8.  
  9. #define NAND_SECTOR_SIZE_LP    2048
  10. #define NAND_BLOCK_MASK_LP     (NAND_SECTOR_SIZE_LP - 1)
  11.  
  12. typedef unsigned int S3C24X0_REG32;
  13.  
  14. /* NAND FLASH (see S3C2410 manual chapter 6) */
  15. typedef struct {
  16.     S3C24X0_REG32   NFCONF;
  17.     S3C24X0_REG32   NFCMD;
  18.     S3C24X0_REG32   NFADDR;
  19.     S3C24X0_REG32   NFDATA;
  20.     S3C24X0_REG32   NFSTAT;
  21.     S3C24X0_REG32   NFECC;
  22. } S3C2410_NAND;
  23.  
  24. /* NAND FLASH (see S3C2440 manual chapter 6, www.100ask.net) */
  25. typedef struct {
  26.     S3C24X0_REG32   NFCONF;
  27.     S3C24X0_REG32   NFCONT;
  28.     S3C24X0_REG32   NFCMD;
  29.     S3C24X0_REG32   NFADDR;
  30.     S3C24X0_REG32   NFDATA;
  31.     S3C24X0_REG32   NFMECCD0;
  32.     S3C24X0_REG32   NFMECCD1;
  33.     S3C24X0_REG32   NFSECCD;
  34.     S3C24X0_REG32   NFSTAT;
  35.     S3C24X0_REG32   NFESTAT0;
  36.     S3C24X0_REG32   NFESTAT1;
  37.     S3C24X0_REG32   NFMECC0;
  38.     S3C24X0_REG32   NFMECC1;
  39.     S3C24X0_REG32   NFSECC;
  40.     S3C24X0_REG32   NFSBLK;
  41.     S3C24X0_REG32   NFEBLK;
  42. } S3C2440_NAND;
  43.  
  44. typedef struct {
  45.     void (*nand_reset)(void);
  46.     void (*wait_idle)(void);
  47.     void (*nand_select_chip)(void);
  48.     void (*nand_deselect_chip)(void);
  49.     void (*write_cmd)(int cmd);
  50.     void (*write_addr)(unsigned int addr);
  51.     unsigned char (*read_data)(void);
  52. }t_nand_chip;
  53.  
  54. static S3C2410_NAND * s3c2410nand = (S3C2410_NAND *)0x4e000000;
  55. static S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
  56.  
  57. static t_nand_chip nand_chip;
  58.  
  59. /* 供外部调用的函数 */
  60. void nand_init(void);
  61. void nand_read(unsigned char *buf, unsigned long start_addr, int size);
  62.  
  63. /* NAND Flash操作的总入口, 它们将调用S3C2410或S3C2440的相应函数 */
  64. static void nand_reset(void);
  65. static void wait_idle(void);
  66. static void nand_select_chip(void);
  67. static void nand_deselect_chip(void);
  68. static void write_cmd(int cmd);
  69. static void write_addr(unsigned int addr);
  70. static unsigned char read_data(void);
  71.  
  72. /* S3C2410的NAND Flash处理函数 */
  73. static void s3c2410_nand_reset(void);
  74. static void s3c2410_wait_idle(void);
  75. static void s3c2410_nand_select_chip(void);
  76. static void s3c2410_nand_deselect_chip(void);
  77. static void s3c2410_write_cmd(int cmd);
  78. static void s3c2410_write_addr(unsigned int addr);
  79. static unsigned char s3c2410_read_data();
  80.  
  81. /* S3C2440的NAND Flash处理函数 */
  82. static void s3c2440_nand_reset(void);
  83. static void s3c2440_wait_idle(void);
  84. static void s3c2440_nand_select_chip(void);
  85. static void s3c2440_nand_deselect_chip(void);
  86. static void s3c2440_write_cmd(int cmd);
  87. static void s3c2440_write_addr(unsigned int addr);
  88. static unsigned char s3c2440_read_data(void);
  89.  
  90. /* S3C2410的NAND Flash操作函数 */
  91.  
  92. /* 复位 */
  93. static void s3c2410_nand_reset(void)
  94. {
  95.     s3c2410_nand_select_chip();
  96.     s3c2410_write_cmd(0xff);  // 复位命令
  97.     s3c2410_wait_idle();
  98.     s3c2410_nand_deselect_chip();
  99. }
  100.  
  101. /* 等待NAND Flash就绪 */
  102. static void s3c2410_wait_idle(void)
  103. {
  104.     int i;
  105.     volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFSTAT;
  106.     while(!(*p & BUSY))
  107.         for(i=; i<; i++);
  108. }
  109.  
  110. /* 发出片选信号 */
  111. static void s3c2410_nand_select_chip(void)
  112. {
  113.     int i;
  114.     s3c2410nand->NFCONF &= ~(<<);
  115.     for(i=; i<; i++);
  116. }
  117.  
  118. /* 取消片选信号 */
  119. static void s3c2410_nand_deselect_chip(void)
  120. {
  121.     s3c2410nand->NFCONF |= (<<);
  122. }
  123.  
  124. /* 发出命令 */
  125. static void s3c2410_write_cmd(int cmd)
  126. {
  127.     volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFCMD;
  128.     *p = cmd;
  129. }
  130.  
  131. /* 发出地址 */
  132. static void s3c2410_write_addr(unsigned int addr)
  133. {
  134.     int i;
  135.     volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFADDR;
  136.  
  137.     *p = addr & 0xff;
  138.     for(i=; i<; i++);
  139.     *p = (addr >> ) & 0xff;
  140.     for(i=; i<; i++);
  141.     *p = (addr >> ) & 0xff;
  142.     for(i=; i<; i++);
  143.     *p = (addr >> ) & 0xff;
  144.     for(i=; i<; i++);
  145. }
  146.  
  147. /* 读取数据 */
  148. static unsigned char s3c2410_read_data(void)
  149. {
  150.     volatile unsigned char *p = (volatile unsigned char *)&s3c2410nand->NFDATA;
  151.     return *p;
  152. }
  153.  
  154. /* S3C2440的NAND Flash操作函数 */
  155.  
  156. /* 复位 */
  157. static void s3c2440_nand_reset(void)
  158. {
  159.     s3c2440_nand_select_chip();
  160.     s3c2440_write_cmd(0xff);  // 复位命令
  161.     s3c2440_wait_idle();
  162.     s3c2440_nand_deselect_chip();
  163. }
  164.  
  165. /* 等待NAND Flash就绪 */
  166. static void s3c2440_wait_idle(void)
  167. {
  168.     int i;
  169.     volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFSTAT;
  170.     while(!(*p & BUSY))
  171.         for(i=; i<; i++);
  172. }
  173.  
  174. /* 发出片选信号 */
  175. static void s3c2440_nand_select_chip(void)
  176. {
  177.     int i;
  178.     s3c2440nand->NFCONT &= ~(<<);
  179.     for(i=; i<; i++);
  180. }
  181.  
  182. /* 取消片选信号 */
  183. static void s3c2440_nand_deselect_chip(void)
  184. {
  185.     s3c2440nand->NFCONT |= (<<);
  186. }
  187.  
  188. /* 发出命令 */
  189. static void s3c2440_write_cmd(int cmd)
  190. {
  191.     volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFCMD;
  192.     *p = cmd;
  193. }
  194.  
  195. /* 发出地址 */
  196. static void s3c2440_write_addr(unsigned int addr)
  197. {
  198.     int i;
  199.     volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR;
  200.  
  201.     *p = addr & 0xff;
  202.     for(i=; i<; i++);
  203.     *p = (addr >> ) & 0xff;
  204.     for(i=; i<; i++);
  205.     *p = (addr >> ) & 0xff;
  206.     for(i=; i<; i++);
  207.     *p = (addr >> ) & 0xff;
  208.     for(i=; i<; i++);
  209. }
  210.  
  211. static void s3c2440_write_addr_lp(unsigned int addr)
  212. {
  213.     int i;
  214.     volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR;
  215.     int col, page;
  216.  
  217.     col = addr & NAND_BLOCK_MASK_LP;
  218.     page = addr / NAND_SECTOR_SIZE_LP;
  219.  
  220.     *p = col & 0xff;            /* Column Address A0~A7 */
  221.     for(i=; i<; i++);
  222.     *p = (col >> ) & 0x0f;     /* Column Address A8~A11 */
  223.     for(i=; i<; i++);
  224.     *p = page & 0xff;            /* Row Address A12~A19 */
  225.     for(i=; i<; i++);
  226.     *p = (page >> ) & 0xff;    /* Row Address A20~A27 */
  227.     for(i=; i<; i++);
  228.     *p = (page >> ) & 0x03;    /* Row Address A28~A29 */
  229.     for(i=; i<; i++);
  230. }
  231.  
  232. /* 读取数据 */
  233. static unsigned char s3c2440_read_data(void)
  234. {
  235.     volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFDATA;
  236.     return *p;
  237. }
  238.  
  239. /* 在第一次使用NAND Flash前，复位一下NAND Flash */
  240. static void nand_reset(void)
  241. {
  242.     nand_chip.nand_reset();
  243. }
  244.  
  245. static void wait_idle(void)
  246. {
  247.     nand_chip.wait_idle();
  248. }
  249.  
  250. static void nand_select_chip(void)
  251. {
  252.     int i;
  253.     nand_chip.nand_select_chip();
  254.     for(i=; i<; i++);
  255. }
  256.  
  257. static void nand_deselect_chip(void)
  258. {
  259.     nand_chip.nand_deselect_chip();
  260. }
  261.  
  262. static void write_cmd(int cmd)
  263. {
  264.     nand_chip.write_cmd(cmd);
  265. }
  266. static void write_addr(unsigned int addr)
  267. {
  268.     nand_chip.write_addr(addr);
  269. }
  270.  
  271. static unsigned char read_data(void)
  272. {
  273.     return nand_chip.read_data();
  274. }
  275.  
  276. /* 初始化NAND Flash */
  277. void nand_init(void)
  278. {
  279. #define TACLS   0
  280. #define TWRPH0  3
  281. #define TWRPH1  0
  282.  
  283.     /* 判断是S3C2410还是S3C2440 */
  284.     if ((GSTATUS1 == 0x32410000) || (GSTATUS1 == 0x32410002))
  285.     {
  286.         nand_chip.nand_reset         = s3c2410_nand_reset;
  287.         nand_chip.wait_idle          = s3c2410_wait_idle;
  288.         nand_chip.nand_select_chip   = s3c2410_nand_select_chip;
  289.         nand_chip.nand_deselect_chip = s3c2410_nand_deselect_chip;
  290.         nand_chip.write_cmd          = s3c2410_write_cmd;
  291.         nand_chip.write_addr         = s3c2410_write_addr;
  292.         nand_chip.read_data          = s3c2410_read_data;
  293.  
  294.         /* 使能NAND Flash控制器, 初始化ECC, 禁止片选, 设置时序 */
  295.         s3c2410nand->NFCONF = (<<)|(<<)|(<<)|(TACLS<<)|(TWRPH0<<)|(TWRPH1<<);
  296.     }
  297.     else
  298.     {
  299.         nand_chip.nand_reset         = s3c2440_nand_reset;
  300.         nand_chip.wait_idle          = s3c2440_wait_idle;
  301.         nand_chip.nand_select_chip   = s3c2440_nand_select_chip;
  302.         nand_chip.nand_deselect_chip = s3c2440_nand_deselect_chip;
  303.         nand_chip.write_cmd          = s3c2440_write_cmd;
  304. #ifdef LARGER_NAND_PAGE
  305.         nand_chip.write_addr         = s3c2440_write_addr_lp;
  306. #else
  307.         nand_chip.write_addr         = s3c2440_write_addr;
  308. #endif
  309.         nand_chip.read_data          = s3c2440_read_data;
  310.  
  311.         /* 设置时序 */
  312.         s3c2440nand->NFCONF = (TACLS<<)|(TWRPH0<<)|(TWRPH1<<);
  313.         /* 使能NAND Flash控制器, 初始化ECC, 禁止片选 */
  314.         s3c2440nand->NFCONT = (<<)|(<<)|(<<);
  315.     }
  316.  
  317.     /* 复位NAND Flash */
  318.     nand_reset();
  319. }
  320.  
  321. /* 读函数 */
  322. void nand_read(unsigned char *buf, unsigned long start_addr, int size)
  323. {
  324.     int i, j;
  325.  
  326. #ifdef LARGER_NAND_PAGE
  327.     if ((start_addr & NAND_BLOCK_MASK_LP) || (size & NAND_BLOCK_MASK_LP)) {
  328.         return ;    /* 地址或长度不对齐 */
  329.     }
  330. #else
  331.     if ((start_addr & NAND_BLOCK_MASK) || (size & NAND_BLOCK_MASK)) {
  332.         return ;    /* 地址或长度不对齐 */
  333.     }
  334. #endif    
  335.  
  336.     /* 选中芯片 */
  337.     nand_select_chip();
  338.  
  339.     for(i=start_addr; i < (start_addr + size);) {
  340.       /* 发出READ0命令 */
  341.       write_cmd();
  342.  
  343.       /* Write Address */
  344.       write_addr(i);
  345. #ifdef LARGER_NAND_PAGE
  346.       write_cmd(0x30);
  347. #endif
  348.       wait_idle();
  349.  
  350. #ifdef LARGER_NAND_PAGE
  351.       for(j=; j < NAND_SECTOR_SIZE_LP; j++, i++) {
  352. #else
  353.       for(j=; j < NAND_SECTOR_SIZE; j++, i++) {
  354. #endif
  355.           *buf = read_data();
  356.           buf++;
  357.       }
  358.     }
  359.  
  360.     /* 取消片选信号 */
  361.     nand_deselect_chip();
  362.  
  363.     return ;
  364. }

uart.c 源码：

  1. #include"uart.h"
  2.  
  3. //uart
  4. #define  ULCON0      (*(volatile unsigned long *)0x50000000)
  5. #define  UCON0       (*(volatile unsigned long *)0x50000004)
  6. #define UFCON0       (*(volatile unsigned long *)0x50000008)
  7. #define UMCON0       (*(volatile unsigned long *)0x5000000c)
  8. #define  UTRSTAT0    (*(volatile unsigned long *)0x50000010)
  9. #define  UERSTAT0    (*(volatile unsigned long *)0x50000014)
  10. #define  UTXH0       (*(volatile unsigned char *)0x50000020)
  11. #define  URXH0       (*(volatile unsigned char *)0x50000024)
  12. #define  UBRDIV0     (*(volatile unsigned long *)0x50000028)
  13.  
  14. //GPH
  15. #define  GPHCON      (*(volatile unsigned long *)0x56000070)
  16. #define  GPHDAT      (*(volatile unsigned long *)0x56000074)
  17. #define  GPHUP       (*(volatile unsigned long *)0x56000078)
  18.  
  19. void uart0_init(void)
  20. {
  21.     GPHCON|=0xa0;
  22.     GPHUP=0x0c;
  23.  
  24.     ULCON0=0x03;
  25.     UCON0=0x05;
  26.     UFCON0=0x00;
  27.     UMCON0=0x00;
  28.     UBRDIV0=((/(*))-);
  29. }
  30.  
  31. unsigned char my_getchar(void)
  32. {
  33.     while(!(UTRSTAT0 & 0x01));
  34.     return URXH0;
  35. }
  36.  
  37. void my_putchar(unsigned char date)
  38. {
  39.     while(!(UTRSTAT0 & 0x02));
  40.     UTXH0=date;
  41. }
  42.  
  43. unsigned char getc(void)
  44. {
  45.      while(!(UTRSTAT0 & 0x01));
  46.      return URXH0;
  47. }
  48.  
  49. void putc(unsigned char c)
  50. {
  51.     while(!(UTRSTAT0 & 0x02));
  52.     UTXH0=c;
  53. }

uart.h 源码：

  1. #ifndef _UART_H_
  2. #define _UART_H_ 
  3.  
  4. void uart0_init(void);
  5. unsigned char my_getchar(void);
  6. void my_putchar(unsigned char date);
  7.  
  8. unsigned char getc(void);
  9. void putc(unsigned char c);
  10.  
  11. #endif

my_stdio.c 源码：

  1. #include"uart.h"
  2. #include"my_stdio.h"
  3.  
  4. typedef char* va_list;
  5.  
  6. #define int_sizeof(type)             ((sizeof(int)+sizeof(type)-1)&~(sizeof(int)-1))
  7.  
  8. #define va_start(para_p,first_para)  (para_p=(va_list)&first_para+int_sizeof(first_para))
  9. #define va_arg(para_p,type)          (*(type *)((para_p+=int_sizeof(type))-int_sizeof(type)))
  10. #define va_end(para_p)               (para_p=(va_list)0)  
  11.  
  12. void my_printf(const char *format, ...)
  13. {
  14.     va_list temp ;
  15.     char *string = format;
  16.     va_start(temp, format);    
  17.  
  18.     while (*string)
  19.     {
  20.         if (*string == '%')
  21.         {
  22.             switch (*++string)
  23.             {
  24.                case 'c':     {  my_putchar(va_arg(temp,char)); break; }
  25.                case 's':
  26.                {
  27.                    char* p = va_arg(temp,char*);
  28.                    while (*p != ) my_putchar(*p++);
  29.                    break;
  30.                }
  31.  
  32.                case 'p':
  33.                {
  34.                    unsigned int addr = (unsigned int)&va_arg(temp, unsigned int), sheft = 0xf0000000;
  35.                    unsigned char temp = ,count=;
  36.                    my_putchar('');
  37.                    my_putchar('x');
  38.                    while (count<)
  39.                    {
  40.                        temp = (unsigned char)(((sheft >> count)&addr) >> ( - count - )) ;
  41.                        if (temp < ) my_putchar(temp + );
  42.                        if (temp >= ) my_putchar(temp+-);
  43.                        count += ;
  44.                    }
  45.                    break;
  46.                }
  47.  
  48.                case 'd':
  49.                {
  50.                    int value = va_arg(temp, int),num=;
  51.                    if (value == ) my_putchar();
  52.                    if (value & 0x80000000)    //负数
  53.                    {
  54.                        my_putchar('-');
  55.                        num = -;
  56.                    }
  57.                    else                       //正数.;
  58.                    while (!(value / num))
  59.                            {
  60.                                num /= ;
  61.                                if (num == )
  62.                                {
  63.                                    my_putchar();
  64.                                    return;
  65.                                }
  66.                             }
  67.                           while (num != )
  68.                                {
  69.                                    my_putchar(value / num+);
  70.                                    value %= num;
  71.                                    num /= ;
  72.                                }
  73.                           break;
  74.                }
  75.  
  76.                case 'f':
  77.                {
  78.                    char *str = "Sorry: function is not available";
  79.                    while (*str != ) my_putchar(*str++);
  80.                }
  81.  
  82.             default: break;
  83.             }
  84.         }
  85.         string++;
  86.     }
  87.     va_end(temp);
  88. }

my_stdio.h 源码：

  1. #ifndef  _OWN_STDIO_H_
  2. #define  _OWN_STDIO_H_
  3.  
  4. void my_printf(const char *format,...);
  5.  
  6. #endif

main.c 源码：

  1. #include"uart.h"
  2. #include"my_stdio.h"
  3. #include"stdio.h"
  4.  
  5. void raise(int sig_nr){;}
  6.  
  7. int main(void)
  8. {
  9.     uart0_init();
  10.  
  11.     printf("%s","   wds_standard   ");
  12.     my_printf("%s","  zsy_standard   ");
  13.  
  14.     while()
  15.     my_putchar(my_getchar()+);    
  16.  
  17.     return ;
  18. }

链接脚本 uart.lds ：

  1. SECTIONS
  2. {
  3.   . = 0x00000000;
  4.   .init : AT(){start.o init.o nand.o}
  5.   . = 0x30000000;
  6.   .text : AT(){*(.text)}
  7.   .rodata ALIGN() :  AT((LOADADDR(.text)+SIZEOF(.text)+)&~(0x03)) {*(.rodata*)}
  8.   .data  ALIGN() :  AT((LOADADDR(.rodata)+SIZEOF(.rodata)+)&~(0x03)) {*(.data)}
  9.   .bss   : {*(.bss) *(COMMON)}
  10.  
  11. }

Makefile:

  1. objs:= start.o init.o uart.o nand.o main.o my_stdio.o lib/libc.a
  2.  
  3. CC            =arm-linux-gcc
  4. LD            =arm-linux-ld
  5. AR            =arm-linux-ar
  6. OBJCOPY       =arm-linux-objcopy
  7. OBJDUMP       =arm-linux-objdump
  8.  
  9. INCLUDEDIR    :=$(shell pwd)/include
  10. CFLAGS        :=-Wall -O2
  11. CPPFLAGS      :=-nostdinc -I$(INCLUDEDIR)
  12.  
  13. export     CC LD OBJCOPY OBJDUMP INCLUDEDIR CFLAGS CPPFLAGS
  14.  
  15. uart.bin:$(objs)
  16.     arm-linux-ld -Tuart.lds -o uart_elf $^ libgcc.a
  17.     arm-linux-objcopy -O binary -S uart_elf $@
  18.     arm-linux-objdump -D -m arm uart_elf > uart.dis
  19.  
  20. .PHONY:lib/libc.a
  21. lib/libc.a:
  22.     cd lib;make;cd ..
  23.  
  24. %.o:%.s
  25.     $(CC) $(CPPFLAGS) $(FLAGS)-o $@ -c $<
  26.  
  27. %.o:%.c
  28.     $(CC) $(CPPFLAGS) $(FLAGS) -o $@ -c $<
  29.  
  30. clean:
  31.     make  clean -C lib
  32.     rm -f *.o *.bin *.dis uart_elf

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