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/* * armboot - Startup Code for ARM926EJS CPU-core */ #include <config.h> #include <common.h> #include <version.h> #if defined(CONFIG_OMAP1610) #include <./configs/omap1510.h> #elif defined(CONFIG_OMAP730) #include <./configs/omap730.h> #endif /* ************************************************************************* * * Jump vector table as in table 3.1 in [1] * ************************************************************************* */ .globl _start _start: b reset // reset 함수로 분기 #ifdef CONFIG_PRELOADER /* No exception handlers in preloader */ ldr pc, _hang ldr pc, _hang ldr pc, _hang ldr pc, _hang ldr pc, _hang ldr pc, _hang ldr pc, _hang _hang: .word do_hang /* pad to 64 byte boundary */ .word 0x12345678 .word 0x12345678 .word 0x12345678 .word 0x12345678 .word 0x12345678 .word 0x12345678 .word 0x12345678 #else //exception vector 설정 ldr pc, _undefined_instruction ldr pc, _software_interrupt ldr pc, _prefetch_abort ldr pc, _data_abort ldr pc, _not_used ldr pc, _irq ldr pc, _fiq //exception vector의 위치 정의 _undefined_instruction: .word undefined_instruction _software_interrupt: .word software_interrupt _prefetch_abort: .word prefetch_abort _data_abort: .word data_abort _not_used: .word not_used _irq: .word irq _fiq: .word fiq #endif /* CONFIG_PRELOADER */ .balignl 16,0xdeadbeef /* ************************************************************************* * * Startup Code (reset vector) * * do important init only if we don't start from memory! * setup Memory and board specific bits prior to relocation. * relocate armboot to ram * setup stack * ************************************************************************* */ _TEXT_BASE: .word TEXT_BASE // RAM에 uboot가 올라가는 주소. Config.mk에 정의되어 있음 // board/armltd/versatile/Config.mk -> TEXT_BASE = 0x01000000 .globl _armboot_start _armboot_start: .word _start //_armboot_start의 address에 _start의 address 저장 /* * These are defined in the board-specific linker script. */ .globl _bss_start // u-boot.lds를 참조하여 bss start, end 주소 설정 _bss_start: .word __bss_start .globl _bss_end _bss_end: .word _end #ifdef CONFIG_USE_IRQ /* IRQ stack memory (calculated at run-time) */ .globl IRQ_STACK_START IRQ_STACK_START: .word 0x0badc0de /* IRQ stack memory (calculated at run-time) */ .globl FIQ_STACK_START FIQ_STACK_START: .word 0x0badc0de #endif /* * the actual reset code */ reset: // start.S에서 제일 처음 분기하는 reset 함수 /* * set the cpu to SVC32 mode */ //arm 동작 모드를 svc(supervisor mode) 모드로 변경 mrs r0,cpsr bic r0,r0,#0x1f orr r0,r0,#0xd3 msr cpsr,r0 /* * we do sys-critical inits only at reboot, * not when booting from ram! */ #ifndef CONFIG_SKIP_LOWLEVEL_INIT // cpu_init_cirt로 분기 // 여기서 MMU를 disable 한뒤 bl cpu_init_crit #endif #ifndef CONFIG_SKIP_RELOCATE_UBOOT //flash memory에서 self 코드(armboot)를 sdram으로 복사 relocate: /* relocate U-Boot to RAM */ adr r0, _start /* r0 <- current position of code */ //_start의 위치를 r0에 저장 ldr r1, _TEXT_BASE /* test if we run from flash or RAM */ cmp r0, r1 /* don't reloc during debug */ // r0와 r1이 같다면 beq stack_setup // stack_setup 수행 ldr r2, _armboot_start // _armboot_start 주소를 r2에 저장 ldr r3, _bss_start //bss_start 위치를 r3에 저장. sub r2, r3, r2 /* r2 <- size of armboot */ add r2, r0, r2 /* r2 <- source end address */ // r3-r2 -> r2 : armboot 크기 // r0+r2 -> r2 : source end 주소 copy_loop: ldmia r0!, {r3-r10} /* copy from source address [r0] */ // r0 위치에서 차례로 데이터를 읽어 r3-r10에 저장 후 r0=r0+12 수행 stmia r1!, {r3-r10} /* copy to target address [r1] */ // r1이 가리키는 address에 r3-r10의 데이터를 저장 cmp r0, r2 /* until source end addreee [r2] */ //r0가 end address인 r2에 동일하면 루프 종료 ble copy_loop #endif /* CONFIG_SKIP_RELOCATE_UBOOT */ /* Set up the stack // stack 설정. stack 초기화 이후부터 c코드 사용 가능 */ stack_setup: ldr r0, _TEXT_BASE /* upper 128 KiB: relocated uboot */ sub sp, r0, #128 /* leave 32 words for abort-stack */ #ifndef CONFIG_PRELOADER sub r0, r0, #CONFIG_SYS_MALLOC_LEN /* malloc area */ sub r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo */ #ifdef CONFIG_USE_IRQ sub r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ) #endif #endif /* CONFIG_PRELOADER */ sub sp, r0, #12 /* leave 3 words for abort-stack */ bic sp, r0, #7 /* 8-byte align stack for ABI compliance */ // r0 - 12 = sp로 저장. sp의 최상단 3 word를 비워두는 이유는 // abort exception이 발생했을 때 exception이 발생하기 전의 pc값과 cpsr 값을 저장하여 debug 정보에 사용하기 위해 clear_bss: // bss 영역 초기화 ldr r0, _bss_start /* find start of bss segment */ ldr r1, _bss_end /* stop here */ mov r2, #0x00000000 /* clear */ #ifndef CONFIG_PRELOADER clbss_l:str r2, [r0] /* clear loop... */ add r0, r0, #4 cmp r0, r1 ble clbss_l bl coloured_LED_init bl red_LED_on #endif /* CONFIG_PRELOADER */ ldr pc, _start_armboot // bss 초기화 후 _start_armboot로 분기 // 이후 부터는 RAM에 복사된 코드 수행 // board_init, Interrupt_init, env_init, init_baudrate 등의 // init 함수 호인터를 순차적으로 call // start_armboot부터는 c 함수이다.(stack이 초기화 되었기 때문에 가능) _start_armboot: #ifdef CONFIG_NAND_SPL // nand spl로 설정되어 있다면 nand_boot 실행 .word nand_boot #else // 아니면 start_armboot 실행 .word start_armboot #endif /* CONFIG_NAND_SPL */ ...

/* * To match the U-Boot user interface on ARM platforms to the U-Boot * standard (as on PPC platforms), some messages with debug character * are removed from the default U-Boot build. * * Define DEBUG here if you want additional info as shown below * printed upon startup: * * U-Boot code: 00F00000 -> 00F3C774 BSS: -> 00FC3274 * IRQ Stack: 00ebff7c * FIQ Stack: 00ebef7c */ #include <common.h> #include <command.h> #include <malloc.h> #include <stdio_dev.h> #include <timestamp.h> #include <version.h> #include <net.h> #include <serial.h> #include <nand.h> #include <onenand_uboot.h> #include <mmc.h> #ifdef CONFIG_BITBANGMII #include <miiphy.h> #endif #ifdef CONFIG_DRIVER_SMC91111 #include "../drivers/net/smc91111.h" #endif #ifdef CONFIG_DRIVER_LAN91C96 #include "../drivers/net/lan91c96.h" #endif DECLARE_GLOBAL_DATA_PTR; ulong monitor_flash_len; #ifdef CONFIG_HAS_DATAFLASH extern int AT91F_DataflashInit(void); extern void dataflash_print_info(void); #endif #ifndef CONFIG_IDENT_STRING #define CONFIG_IDENT_STRING "" #endif const char version_string[] = U_BOOT_VERSION" (" U_BOOT_DATE " - " U_BOOT_TIME ")"CONFIG_IDENT_STRING; #ifdef CONFIG_DRIVER_RTL8019 extern void rtl8019_get_enetaddr (uchar * addr); #endif #if defined(CONFIG_HARD_I2C) || \ defined(CONFIG_SOFT_I2C) #include <i2c.h> #endif /************************************************************************ * Coloured LED functionality ************************************************************************ * May be supplied by boards if desired */ void inline __coloured_LED_init (void) {} void coloured_LED_init (void) __attribute__((weak, alias("__coloured_LED_init"))); void inline __red_LED_on (void) {} void red_LED_on (void) __attribute__((weak, alias("__red_LED_on"))); void inline __red_LED_off(void) {} void red_LED_off(void) __attribute__((weak, alias("__red_LED_off"))); void inline __green_LED_on(void) {} void green_LED_on(void) __attribute__((weak, alias("__green_LED_on"))); void inline __green_LED_off(void) {} void green_LED_off(void) __attribute__((weak, alias("__green_LED_off"))); void inline __yellow_LED_on(void) {} void yellow_LED_on(void) __attribute__((weak, alias("__yellow_LED_on"))); void inline __yellow_LED_off(void) {} void yellow_LED_off(void) __attribute__((weak, alias("__yellow_LED_off"))); void inline __blue_LED_on(void) {} void blue_LED_on(void) __attribute__((weak, alias("__blue_LED_on"))); void inline __blue_LED_off(void) {} void blue_LED_off(void) __attribute__((weak, alias("__blue_LED_off"))); /************************************************************************ * Init Utilities * ************************************************************************ * Some of this code should be moved into the core functions, * or dropped completely, * but let's get it working (again) first... */ #if defined(CONFIG_ARM_DCC) && !defined(CONFIG_BAUDRATE) #define CONFIG_BAUDRATE 115200 #endif static int init_baudrate (void) { char tmp[64]; /* long enough for environment variables */ int i = getenv_r ("baudrate", tmp, sizeof (tmp)); gd->bd->bi_baudrate = gd->baudrate = (i > 0) ? (int) simple_strtoul (tmp, NULL, 10) : CONFIG_BAUDRATE; return (0); } static int display_banner (void) { printf ("\n\n%s\n\n", version_string); debug ("U-Boot code: %08lX -> %08lX BSS: -> %08lX\n", _armboot_start, _bss_start, _bss_end); #ifdef CONFIG_MODEM_SUPPORT debug ("Modem Support enabled\n"); #endif #ifdef CONFIG_USE_IRQ debug ("IRQ Stack: %08lx\n", IRQ_STACK_START); debug ("FIQ Stack: %08lx\n", FIQ_STACK_START); #endif return (0); } /* * WARNING: this code looks "cleaner" than the PowerPC version, but * has the disadvantage that you either get nothing, or everything. * On PowerPC, you might see "DRAM: " before the system hangs - which * gives a simple yet clear indication which part of the * initialization if failing. */ static int display_dram_config (void) { int i; #ifdef DEBUG puts ("RAM Configuration:\n"); for(i=0; i<CONFIG_NR_DRAM_BANKS; i++) { printf ("Bank #%d: %08lx ", i, gd->bd->bi_dram[i].start); print_size (gd->bd->bi_dram[i].size, "\n"); } #else ulong size = 0; for (i=0; i<CONFIG_NR_DRAM_BANKS; i++) { size += gd->bd->bi_dram[i].size; } puts("DRAM: "); print_size(size, "\n"); #endif return (0); } #ifndef CONFIG_SYS_NO_FLASH static void display_flash_config (ulong size) { puts ("Flash: "); print_size (size, "\n"); } #endif /* CONFIG_SYS_NO_FLASH */ #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C) static int init_func_i2c (void) { puts ("I2C: "); i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); puts ("ready\n"); return (0); } #endif #if defined(CONFIG_CMD_PCI) || defined (CONFIG_PCI) #include <pci.h> static int arm_pci_init(void) { pci_init(); return 0; } #endif /* CONFIG_CMD_PCI || CONFIG_PCI */ /* * Breathe some life into the board... * * Initialize a serial port as console, and carry out some hardware * tests. * * The first part of initialization is running from Flash memory; * its main purpose is to initialize the RAM so that we * can relocate the monitor code to RAM. */ /* * All attempts to come up with a "common" initialization sequence * that works for all boards and architectures failed: some of the * requirements are just _too_ different. To get rid of the resulting * mess of board dependent #ifdef'ed code we now make the whole * initialization sequence configurable to the user. * * The requirements for any new initalization function is simple: it * receives a pointer to the "global data" structure as it's only * argument, and returns an integer return code, where 0 means * "continue" and != 0 means "fatal error, hang the system". */ typedef int (init_fnc_t) (void); int print_cpuinfo (void); init_fnc_t *init_sequence[] = { #if defined(CONFIG_ARCH_CPU_INIT) arch_cpu_init, /* basic arch cpu dependent setup */ #endif board_init, /* basic board dependent setup */ #if defined(CONFIG_USE_IRQ) interrupt_init, /* set up exceptions */ #endif timer_init, /* initialize timer */ #ifdef CONFIG_FSL_ESDHC get_clocks, #endif env_init, /* initialize environment */ init_baudrate, /* initialze baudrate settings */ serial_init, /* serial communications setup */ console_init_f, /* stage 1 init of console */ display_banner, /* say that we are here */ #if defined(CONFIG_DISPLAY_CPUINFO) print_cpuinfo, /* display cpu info (and speed) */ #endif #if defined(CONFIG_DISPLAY_BOARDINFO) checkboard, /* display board info */ #endif #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C) init_func_i2c, #endif dram_init, /* configure available RAM banks */ #if defined(CONFIG_CMD_PCI) || defined (CONFIG_PCI) arm_pci_init, #endif display_dram_config, NULL, };

void start_armboot (void) { init_fnc_t **init_fnc_ptr; // 보드의 장치 초기화를 위한 함수 포인터 배열 char *s; #if defined(CONFIG_VFD) || defined(CONFIG_LCD) unsigned long addr; #endif /* Pointer is writable since we allocated a register for it */ //global_data.h에 정의되어 있으며 baudrate, board specific(bd_t* bd), relocation offset, // environment variable address, fram-buffer addr, cpu clock, bus clock, ram size // reset status, jump table 등의 정보를 가지고 있다 gd = (gd_t*)(_armboot_start - CONFIG_SYS_MALLOC_LEN - sizeof(gd_t)); // gd 포인터 설정 /* compiler optimization barrier needed for GCC >= 3.4 */ __asm__ __volatile__("": : :"memory"); // 메모리 초기화(gd, bd 메모리를 clear) memset ((void*)gd, 0, sizeof (gd_t)); gd->bd = (bd_t*)((char*)gd - sizeof(bd_t)); memset (gd->bd, 0, sizeof (bd_t)); gd->flags |= GD_FLG_RELOC; // relocation flag 설정 monitor_flash_len = _bss_start - _armboot_start; // 루프를 돌면서 board에 관련된 모든 차원을 초기화 // 초기화는 init_sequence에 선언된 순서대로 진행 // 위에 init_sequence 정의되어 있음.(arch_cpu_init, board_init, 등) for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) { if ((*init_fnc_ptr)() != 0) { // 에러 발생시 reset 메시지 출력 hang (); } } /* armboot_start is defined in the board-specific linker script */ // heap 영역 설정 mem_malloc_init (_armboot_start - CONFIG_SYS_MALLOC_LEN, CONFIG_SYS_MALLOC_LEN); #ifndef CONFIG_SYS_NO_FLASH /* configure available FLASH banks */ // flash를 초기화 하고 flash의 size를 console에 출력 display_flash_config (flash_init ()); #endif /* CONFIG_SYS_NO_FLASH */ #ifdef CONFIG_VFD # ifndef PAGE_SIZE # define PAGE_SIZE 4096 # endif /* * reserve memory for VFD display (always full pages) */ /* bss_end is defined in the board-specific linker script */ addr = (_bss_end + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1); vfd_setmem (addr); gd->fb_base = addr; #endif /* CONFIG_VFD */ #ifdef CONFIG_LCD /* board init may have inited fb_base */ if (!gd->fb_base) { # ifndef PAGE_SIZE # define PAGE_SIZE 4096 # endif /* * reserve memory for LCD display (always full pages) */ /* bss_end is defined in the board-specific linker script */ addr = (_bss_end + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1); lcd_setmem (addr); gd->fb_base = addr; } #endif /* CONFIG_LCD */ #if defined(CONFIG_CMD_NAND) puts ("NAND: "); nand_init(); /* go init the NAND */ #endif #if defined(CONFIG_CMD_ONENAND) onenand_init(); #endif #ifdef CONFIG_HAS_DATAFLASH AT91F_DataflashInit(); dataflash_print_info(); #endif /* initialize environment */ // flash 에서 sdram으로 복사 env_relocate (); #ifdef CONFIG_VFD /* must do this after the framebuffer is allocated */ drv_vfd_init(); #endif /* CONFIG_VFD */ #ifdef CONFIG_SERIAL_MULTI serial_initialize(); #endif /* IP Address */ gd->bd->bi_ip_addr = getenv_IPaddr ("ipaddr"); stdio_init (); /* get the devices list going. */ jumptable_init (); #if defined(CONFIG_API) /* Initialize API */ api_init (); #endif console_init_r (); /* fully init console as a device */ #if defined(CONFIG_ARCH_MISC_INIT) /* miscellaneous arch dependent initialisations */ arch_misc_init (); #endif #if defined(CONFIG_MISC_INIT_R) /* miscellaneous platform dependent initialisations */ misc_init_r (); #endif /* enable exceptions */ // 인터럽트 enable enable_interrupts (); /* Perform network card initialisation if necessary */ #ifdef CONFIG_DRIVER_TI_EMAC /* XXX: this needs to be moved to board init */ extern void davinci_eth_set_mac_addr (const u_int8_t *addr); if (getenv ("ethaddr")) { uchar enetaddr[6]; eth_getenv_enetaddr("ethaddr", enetaddr); davinci_eth_set_mac_addr(enetaddr); } #endif #if defined(CONFIG_DRIVER_SMC91111) || defined (CONFIG_DRIVER_LAN91C96) /* XXX: this needs to be moved to board init */ if (getenv ("ethaddr")) { uchar enetaddr[6]; eth_getenv_enetaddr("ethaddr", enetaddr); smc_set_mac_addr(enetaddr); } #endif /* CONFIG_DRIVER_SMC91111 || CONFIG_DRIVER_LAN91C96 */ /* Initialize from environment */ if ((s = getenv ("loadaddr")) != NULL) { load_addr = simple_strtoul (s, NULL, 16); } #if defined(CONFIG_CMD_NET) if ((s = getenv ("bootfile")) != NULL) { copy_filename (BootFile, s, sizeof (BootFile)); } #endif #ifdef BOARD_LATE_INIT board_late_init (); #endif #ifdef CONFIG_GENERIC_MMC puts ("MMC: "); mmc_initialize (gd->bd); #endif #ifdef CONFIG_BITBANGMII bb_miiphy_init(); #endif #if defined(CONFIG_CMD_NET) #if defined(CONFIG_NET_MULTI) puts ("Net: "); #endif eth_initialize(gd->bd); #if defined(CONFIG_RESET_PHY_R) debug ("Reset Ethernet PHY\n"); reset_phy(); #endif #endif /* main_loop() can return to retry autoboot, if so just run it again. */ for (;;) { main_loop (); // main loop 진입 } /* NOTREACHED - no way out of command loop except booting */ } void hang (void) { puts ("### ERROR ### Please RESET the board ###\n"); for (;;); }

... void main_loop (void) { #ifndef CONFIG_SYS_HUSH_PARSER static char lastcommand[CONFIG_SYS_CBSIZE] = { 0, }; int len; int rc = 1; int flag; #endif ... #endif /* CONFIG_BOOTCOUNT_LIMIT */ s = getenv ("bootcmd"); // uboot/include/configs/versatile.h에 bootcmd가 정의되어 있으면 가져온다. // 현재 #define CONFIG_BOOTCOMMAND "bootm 0x210000 0x510000" 로 설정 debug ("### main_loop: bootcmd=\"%s\"\n", s ? s : "<UNDEFINED>"); if (bootdelay >= 0 && s && !abortboot (bootdelay)) { // abortboot 함수 내부에서 3초 이내에 입력이 없으면 자동 부팅 실행 # ifdef CONFIG_AUTOBOOT_KEYED int prev = disable_ctrlc(1); /* disable Control C checking */ # endif # ifndef CONFIG_SYS_HUSH_PARSER run_command (s, 0); // run_command 호출 # else parse_string_outer(s, FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP); # endif

int run_command (const char *cmd, int flag) { cmd_tbl_t *cmdtp; char cmdbuf[CONFIG_SYS_CBSIZE]; /* working copy of cmd */ char *token; /* start of token in cmdbuf */ char *sep; /* end of token (separator) in cmdbuf */ char finaltoken[CONFIG_SYS_CBSIZE]; char *str = cmdbuf; char *argv[CONFIG_SYS_MAXARGS + 1]; /* NULL terminated */ int argc, inquotes; int repeatable = 1; int rc = 0; printf ("[RUN_COMMAND] cmd[%p]=\"\n", cmd); puts (cmd ? cmd : "NULL"); /* use puts - string may be loooong */ puts ("\"\n"); clear_ctrlc(); /* forget any previous Control C */ if (!cmd || !*cmd) { return -1; /* empty command */ } if (strlen(cmd) >= CONFIG_SYS_CBSIZE) { puts ("## Command too long!\n"); return -1; } strcpy (cmdbuf, cmd); /* Process separators and check for invalid * repeatable commands */ printf ("[PROCESS_SEPARATORS] %s\n", cmd); while (*str) { /* * Find separator, or string end * Allow simple escape of ';' by writing "\;" */ for (inquotes = 0, sep = str; *sep; sep++) { if ((*sep=='\'') && (*(sep-1) != '\\')) inquotes=!inquotes; if (!inquotes && (*sep == ';') && /* separator */ ( sep != str) && /* past string start */ (*(sep-1) != '\\')) /* and NOT escaped */ break; } /* * Limit the token to data between separators */ token = str; if (*sep) { str = sep + 1; /* start of command for next pass */ *sep = '\0'; } else str = sep; /* no more commands for next pass */ #ifdef DEBUG_PARSER printf ("token: \"%s\"\n", token); #endif /* find macros in this token and replace them */ process_macros (token, finaltoken); /* Extract arguments */ if ((argc = parse_line (finaltoken, argv)) == 0) { rc = -1; /* no command at all */ continue; } /* Look up command in command table */ if ((cmdtp = find_cmd(argv[0])) == NULL) { // cmd 인자 찾기. 현재 argv[0]는 bootm임 // bootm command와 일치하는 command list에서 찾아오기 printf ("Unknown command '%s' - try 'help'\n", argv[0]); rc = -1; /* give up after bad command */ continue; } printf("argv[0] : %s\n",argv[0]); // for debug -> 'bootm' /* found - check max args */ if (argc > cmdtp->maxargs) { cmd_usage(cmdtp); rc = -1; continue; } #if defined(CONFIG_CMD_BOOTD) /* avoid "bootd" recursion */ if (cmdtp->cmd == do_bootd) { printf ("[%s]\n", finaltoken); if (flag & CMD_FLAG_BOOTD) { puts ("'bootd' recursion detected\n"); rc = -1; continue; } else { flag |= CMD_FLAG_BOOTD; } } #endif /* OK - call function to do the command */ // cmd_bootm.c의 do_bootm() 함수 실행 if ((cmdtp->cmd) (cmdtp, flag, argc, argv) != 0) { rc = -1; } repeatable &= cmdtp->repeatable; /* Did the user stop this? */ if (had_ctrlc ()) return -1; /* if stopped then not repeatable */ } return rc ? rc : repeatable; }

int do_bootm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) { ulong iflag; ulong load_end = 0; int ret; boot_os_fn *boot_fn; #ifndef CONFIG_RELOC_FIXUP_WORKS static int relocated = 0; /* relocate boot function table */ if (!relocated) { int i; for (i = 0; i < ARRAY_SIZE(boot_os); i++) if (boot_os[i] != NULL) boot_os[i] += gd->reloc_off; relocated = 1; } #endif /* determine if we have a sub command */ if (argc > 1) { char *endp; printf("argv[0], argv[1] -> %s, %s",argv[0],argv[1]); simple_strtoul(argv[1], &endp, 16); /* endp pointing to NULL means that argv[1] was just a * valid number, pass it along to the normal bootm processing * * If endp is ':' or '#' assume a FIT identifier so pass * along for normal processing. * * Right now we assume the first arg should never be '-' */ if ((*endp != 0) && (*endp != ':') && (*endp != '#')) { printf("start do_bootm_subcommand"); return do_bootm_subcommand(cmdtp, flag, argc, argv); } } printf("start bootm_start"); if (bootm_start(cmdtp, flag, argc, argv)) // 부팅 image 찾기, kernel+ramdisk return 1; /* * We have reached the point of no return: we are going to * overwrite all exception vector code, so we cannot easily * recover from any failures any more... */ iflag = disable_interrupts(); #if defined(CONFIG_CMD_USB) /* * turn off USB to prevent the host controller from writing to the * SDRAM while Linux is booting. This could happen (at least for OHCI * controller), because the HCCA (Host Controller Communication Area) * lies within the SDRAM and the host controller writes continously to * this area (as busmaster!). The HccaFrameNumber is for example * updated every 1 ms within the HCCA structure in SDRAM! For more * details see the OpenHCI specification. */ usb_stop(); #endif #ifdef CONFIG_AMIGAONEG3SE /* * We've possible left the caches enabled during * bios emulation, so turn them off again */ icache_disable(); dcache_disable(); #endif ret = bootm_load_os(images.os, &load_end, 1); // 부팅 image 로딩, kernel // bootm_load_os 함수는 아래에서 확인 ... boot_fn = boot_os[images.os.os]; if (boot_fn == NULL) { if (iflag) enable_interrupts(); printf ("ERROR: booting os '%s' (%d) is not supported\n", genimg_get_os_name(images.os.os), images.os.os); show_boot_progress (-8); return 1; } arch_preboot_os(); boot_fn(0, argc, argv, &images); //실제 kernel로 진입. -> do_bootm_linux 호출 ...

int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images) { bd_t *bd = gd->bd; char *s; int machid = bd->bi_arch_number; void (*theKernel)(int zero, int arch, uint params); #ifdef CONFIG_CMDLINE_TAG char *commandline = getenv ("bootargs"); //bootargs를 가져와서 commandline에 저장 printf("in do_bootm_linux-> commandline : %s\n",commandline); #endif if ((flag != 0) && (flag != BOOTM_STATE_OS_GO)) return 1; theKernel = (void (*)(int, int, uint))images->ep; s = getenv ("machid"); // machine id를 가져온다 if (s) { machid = simple_strtoul (s, NULL, 16); printf ("Using machid 0x%x from environment\n", machid); } show_boot_progress (15); debug ("## Transferring control to Linux (at address %08lx) ...\n", (ulong) theKernel); #if defined (CONFIG_SETUP_MEMORY_TAGS) || \ defined (CONFIG_CMDLINE_TAG) || \ defined (CONFIG_INITRD_TAG) || \ defined (CONFIG_SERIAL_TAG) || \ defined (CONFIG_REVISION_TAG) || \ defined (CONFIG_LCD) || \ defined (CONFIG_VFD) setup_start_tag (bd); #ifdef CONFIG_SERIAL_TAG setup_serial_tag (&params); #endif #ifdef CONFIG_REVISION_TAG setup_revision_tag (&params); #endif #ifdef CONFIG_SETUP_MEMORY_TAGS setup_memory_tags (bd); #endif #ifdef CONFIG_CMDLINE_TAG setup_commandline_tag (bd, commandline); #endif #ifdef CONFIG_INITRD_TAG if (images->rd_start && images->rd_end) setup_initrd_tag (bd, images->rd_start, images->rd_end); #endif #if defined (CONFIG_VFD) || defined (CONFIG_LCD) setup_videolfb_tag ((gd_t *) gd); #endif setup_end_tag (bd); #endif /* we assume that the kernel is in place */ printf ("\nStarting kernel ...\n\n"); #ifdef CONFIG_USB_DEVICE { extern void udc_disconnect (void); udc_disconnect (); } #endif cleanup_before_linux (); theKernel (0, machid, bd->bi_boot_params); // kernel image로 제어권을 넘기기 /* does not return */ return 1; }