u-boot-2014.10移植（8）重定位，支援NAND啟動
阿新 • • 發佈：2018-11-03
前面連結地址都是0x0，可以從nor正常啟動核心和檔案系統。
現在把連結地址改成0x33f00000 一旦更改了連結地址， u-boot從nor flash載入時，串列埠沒有任何輸出 新增檔案boot_init.c
現在把連結地址改成0x33f00000 一旦更改了連結地址， u-boot從nor flash載入時，串列埠沒有任何輸出 新增檔案boot_init.c
#define NFCONF (*((volatile unsigned long *)0x4E000000)) #define NFCONT (*((volatile unsigned long *)0x4E000004)) #define NFCMMD (*((volatile unsigned char *)0x4E000008)) #define NFADDR (*((volatile unsigned char *)0x4E00000C)) #defineNFDATA (*((volatile unsigned char *)0x4E000010)) #define NFSTAT (*((volatile unsigned char *)0x4E000020)) static void nand_select(void) { NFCONT &= ~(1<<1); } static void nand_deselect(void) { NFCONT |= (1<<1); } static void nand_cmd(unsigned char cmd) {volatile int i; NFCMMD = cmd; for (i = 0; i < 10; i++); } static void nand_addr(unsigned int addr) { unsigned int col = addr % 2048; unsigned int page = addr / 2048; volatile int i; NFADDR = col & 0xff; for (i = 0; i < 10; i++); NFADDR = (col >> 8) & 0xff; for (i = 0; i < 10; i++); NFADDR = page & 0xff; for (i = 0; i < 10; i++); NFADDR = (page >> 8) & 0xff; for (i = 0; i < 10; i++); NFADDR = (page >> 16) & 0xff; for (i = 0; i < 10; i++); } static void nand_wait_ready(void) { while (!(NFSTAT & 1)); } static unsigned char nand_data(void) { return NFDATA; } static void nand_read_ll(unsigned int addr, unsigned char *buf, unsigned int len) { int col = addr % 2048; int i = 0; nand_select(); while (i < len) { nand_cmd(0x00); nand_addr(addr); nand_cmd(0x30); nand_wait_ready(); for (; (col < 2048) && (i < len); col++) { buf[i] = nand_data(); i++; addr++; } col = 0; } nand_deselect(); } static void nand_init(void) { #define TACLS 0 #define TWRPH0 1 #define TWRPH1 0 NFCONF = (TACLS<<12)|(TWRPH0<<8)|(TWRPH1<<4); NFCONT = (1<<4)|(1<<1)|(1<<0); } /* 1: from nor 0: from nand */ static int isBootFromNorFlash(void) { volatile int *p = (volatile int *)0; int val; val = *p; *p = 0x12345678; if (*p == 0x12345678) { *p = val; return 0; } else { // nor return 1; } } void copy_code_to_sdram(unsigned char *src, unsigned char *dest, unsigned int len) { int i = 0; if (isBootFromNorFlash()) { while (i < len) { dest[i] = src[i]; i++; } } else // from nand { nand_init(); nand_read_ll((unsigned int)src, dest, len); } } void clear_bss(void) { extern int __bss_start, __bss_end; int *p = &__bss_start; for (; p < &__bss_end; p++) *p = 0; }
修改對應目錄Makefile
obj-y := smdk2440.o boot_init.o
把smdk2440/目錄下內容放最前面，滿足4K內
vim arch/arm/cpu/u-boot.lds
board/samsung/smdk2440/built-in.o (.text*)
修改重定位程式碼：
#if defined(CONFIG_SYS_MALLOC_F_LEN) && !defined(CONFIG_SPL_BUILD) sub sp, sp, #CONFIG_SYS_MALLOC_F_LEN str sp, [r9, #GD_MALLOC_BASE] #endif #if defined(CONFIG_S3C2440) mov r0, #0 ldr r1, = CONFIG_SYS_TEXT_BASE ldr r2, = CONFIG_SYS_TEXT_BASE ldr r3, =__bss_end sub r2, r3, r2 bl copy_code_to_sdram bl clear_bss ldr pc, =call_board_init_f call_board_init_f: mov r0, #0 bl board_init_f ldr sp, [r9, #GD_START_ADDR_SP] /* sp = gd->start_addr_sp */ bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ ldr r9, [r9, #GD_BD] /* r9 = gd->bd */ sub r9, r9, #GD_SIZE /* new GD is below bd */ mov r0, r9 ldr r1, = CONFIG_SYS_TEXT_BASE bl board_init_r #else /* mov r0, #0 not needed due to above code */ bl board_init_f ... #endif
去掉pie選項vim arch/arm/config.mk
#LDFLAGS_u-boot += -pie
#ALL-y += checkarmreloc
此外board.c裡面還應修改
board_init_f //addr -= gd->mon_len; //addr &= ~(4096 - 1); addr = CONFIG_SYS_TEXT_BASE ;
燒寫u-boot到nand
bootloader: tftp 30000000 u-boot.bin nand erase.part bootloader nand write.jffs2 30000000 bootloader
燒寫u-boot到nor
tftp 30000000 u-boot.bin protect off all erase 0 3ffff (256K) cp.b 30000000 0 40000