ARM学习报告003——Bios源码分析.doc

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1 ARM 003 Hayden Luo BIOS

2 Hayden Luo Bios BootLoader BIOS ARM Bootloader uclinux ARM ARM ARM ARM ARM ARM GNU ARM elf section ARM linux ARM 002 head.s Makefile bios.ld BIOS bios 003 Hayden Luo Bios bios-dyh Hayden Luo Bios Hayden Luo Bios bios Hayden Luo Bios bios-lt Hayden Luo Bios google liu tao bios-lt74 Hayden Luo Bios liu tao bios bios-lt74 Hayden Luo Bios bios-lt74 bios-dyh bios-lt74 BIOS

3 BIOS 1.1 BIOS bios 1 bios-dyh Hayden Luo Bios setup fdisk setup fdisk 1 bios-dyh

4 1 bios-dyh Makefile bios 1.2 Makefile /bios-dyh/makefile Makefile Linux Makefile all: all: make -C sysinit make -C biosapi make -C tftp make -C uart_rec make bios.bin make -C imgtools/param make -C imgtools/img Makefile 1 make 1 sysinit biosapi tftp uart_rec bin2c C C make bios.bin 1 C.o bios.ld bios objcopy section bios.bin 1 combine bios.bin imgtools/img bios.img bios.img ROM Bootloader BIOS BIOS bootloader bootloader BIOS 1 BIOS linux BIOS

5 BIOS BIOS 6 sysinit biosapi tftp urat_rec BIOS sysinit biosapi tftp urat_rec BIOS 2.1 BIOS sysinit biosapi tftp urat_rec Makefile.ld sysinit BIN2C CFLAGS += -I.. AFLAGS += -I.. =../tools/bin2c /sysinit/makefile OBJ = head.o sysinit.o all:../sysinit.c../sysinit.c: sysinit.bin $(BIN2C) -c -s sysinit_data sysinit.bin../sysinit.c sysinit.bin: sysinit $(OBJCOPY) -O binary --only-section=.init \ --only-section=.text \ --only-section=.rodata \ --only-section=.data \ --only-section=.bss sysinit \ sysinit.bin sysinit: $(OBJ) $(LD) -p -X -T sysinit.ld $(OBJ) \ -o sysinit clean: $(RM) -rf *.o sysinit sysinit.bin../sysinit.c %.o: %.c $(CC) $(CFLAGS) -c -o $@ $<

6 %.o: %.S $(CC) $(AFLAGS) -c -o $< /sysinit/makefile sysinit.s head.s sysinit sysinit.o GNU/linux BIOS ARM 002 GNU/linux 1 BIOS object CPU sysinit sysinit 0x03fe0000 sysinit PC 0x03fe0000 sysinit sysinit BIOS Makefile /sysinit/makefile sysinit.bin: sysinit $(OBJCOPY) -O binary --only-section=.init \ --only-section=.text \ --only-section=.rodata \ --only-section=.data \ --only-section=.bss sysinit \ sysinit.bin Makefile arm-elf-objcopy sysinit elf.init.text.rodata.data.bss ARM sysinit.bin elf elf elf.systab.syntab ARM sysinit.bin flash.text ro_base /sysinit.c: sysinit.bin $(BIN2C) -c -s sysinit_data sysinit.bin../sysinit.c bin2c sysinit.bin sysinit_data[] C C C unsigned char sysinit_data[] sysinit.bin ultraedit sysinit.bin sysinit.bin sysinit.c.o sysinit.o sysinit sysinit.o symbol table sysinit_data BIOS sysinit_data

7 sysinit.bin bios bios GNU/linux sysinit ld /sysinit/sysinit.ld OUTPUT_ARCH(arm) ENTRY(stext) SECTIONS {.text 0x03fe0000 : { /* Real text segment */ _text =.; /* Text and read-only data */ *(.text) *(.rodata). = ALIGN(4); _etext =.; /* End of text section */.data : { data_start =.; *(.data). = ALIGN(4); _edata =.;.bss : { bss_start =.; /* BSS */ *(.bss). = ALIGN(4); _end =.; 002.o sysinit head.o sysinit.o.o.c.s stext /sysinit/head.s head.s stext=0x03fe0000.text 0x03fe0000 ro_base 0x03fe0000 sysinit.bin 0x03fe0000 sysinit.bin 0x03fe0000 S3C4510B SRAM

8 .data.bss.text BIOS sysinit biosapi tftp urat_rec windows BIOS Bootloader bin2c bin BIOS BIOS bios-dyh Hayden Luo Bios BIOS BIOS biosapi tftp sysinit biosapi.text 0x data.bss tftp.text 0x data.bss sysinit 0x03fe0000 biosapi 0x tftp urat_rec 0x x bin2c+.bin 2.2 bios.bin bin2c c BIOS make bios.bin bios 1 make bios.bin Makefile OBJ = head.o bios.o gunzip.o utils.o console.o bioscall.o \ sysinit.o biosapi.o tftp.o uart_rec.o /Makefile bios.bin: bios $(OBJCOPY) -O binary \ --only-section=.init \ --only-section=.text \ --only-section=.rodata \ --only-section=.data \ --only-section=.bss bios bios.bin

9 bios: $(OBJ) $(LD) -p -X -T bios.ld $(OBJ) \ -o bios Makefile bios.bin bios section arm-elf-objcopy bios Makefile bios.o OBJ = head.o bios.o gunzip.o utils.o console.o bioscall.o sysinit.o biosapi.o tftp.o uart_rec.o 1.o.o arm-elf-gcc c 1 c c head.s bios_main bios.c c bios bios_main gunzip.c biosapi tftp utils.c bioscall.c biosapi console.c borad.h config.h ROM DRAM c.h gcc.o 1 rel<.section> symbol table.o.ld bios bios bootloader bios c arm-elf-gcc.o 1.o o.text.rodata.data.bss.rel<section>.symtab ld GNU ld.ld.o 002.text.rodata.data.bss RO RW ZI symbol table symbol table.o symbol symbol symbol.rel<section> bios SECTIONS {.text 0x : { /* Real text segment */ _text =.; /* Text and read-only data */ /Makefile

10 *(.text) *(.rodata). = ALIGN(4); _etext =.; /* End of text section */ bios 0x ro_base=0x Mbyte flash ARM 001 ro_base 0x flash 0x flash bios.img bios.bin bios flash 99% bios flash bios.img bios 0x S3C4510B ROMCON0 0x x ROM0 S3C4510B ROM0 ROM0 Flash flash 0x0 0x M ROMCON0 22 0:21 32bits 4M 32bit=4M words=16m bytes ROM0 32Mbytes ROMCON0 ROM0 16M 16M 0x

11 PC 0x M x0 PC 0x x0 ROM0 flash 1M 16 2M 20 ADDR[19:0] 2M ROM0 32M flsh ROM0 ADDR20 flash ADDR[19:0] 2M 4M 6M 8M 16M 18M 30M Bootloader bios 0x M BIOS 2.3 bios.img bios.bin flash /imgtools/img bios.img 1 bios bios.bin bios.img bios bios.bin bios.img bios elf flash 99 Bootloader elf.text.rodata.data.bss bios.bin bin flash BIOS bios.img flash param.tbl bootloader bios.bin 0xe000 bios.img 0xe000 bios 0 0xe000 param.tbl

12 BIOS config.h #define SYSTEM_TABLE_OFFSET 0x0000e000 /imgtools/param param.c param.tbl mbr.bin param.tbl /imgtools/param/param.c int main() { FILE *f; f = fopen("param.tbl", "wb"); fwrite((char *)(&system_table), 1, sizeof(struct system_table_struct), f); fclose(f); f = fopen("mbr.bin", "wb"); fwrite((char *)(&partition_table), 1, sizeof(struct partition_table_struct), f); fclose(f); return 0; param.c param.tbl mbr.bin system_table param.c struct system_table_struct system_table system_table system_table_struct BIOS param.tbl BIOS! Bios.img /imgtools/img/ /imgtools/img/makefile bios:../tools/combine../../bios.bin -a 0x7f00../param/param.tbl bios.img /imgtools/img/makefile Makefile bios.img tools combine bios.img bios.bin param.tbl param.tbl 0xe000 ultraedit param.tbl 0x7f00 bios 0x7f00 bios.img bios bios BIOS BIOS

13 BIOS BIOS BIOS. ARM Let s go!! 3.1 BIOS head.s BIOS linux Makefile Makefile OBJ = head.o bios.o gunzip.o utils.o console.o bioscall.o \ sysinit.o biosapi.o tftp.o uart_rec.o /Makefile bios: $(OBJ) $(LD) -p -X -T bios.ld $(OBJ) \ -o bios Makefile.o ADS head.o bios head.s head.o.text bios.text head.s head.s 002 head.s.globl stext.globl system_table_offset.globl _rom_base stext system_table_offset _rom_base system_table_offset:.long SYSTEM_TABLE_OFFSET SYSTEM_TABLE_OFFSET:.long stext SYSTEM_TABLE_OFFSET config.h param.tbl _rom_base head.s bios.img bios.img flash _rom_base ROM /* * Load up the linker defined values for the static data copy */ ldr r0, =_etext

14 ldr r1, = data_start ldr r3, =_edata ARM 002 _etext data_start _edata bios.ld head.s 002.data.bss twentyone bootloader bootloader RW rw_base RW.data ZI.bss cpsr ARM SVC stack cache bios bios_start: bl bios_main bios_main c bios Head.S bl bios_main twentyone /head.s mov r3, r0 r0 r3 r0 SYSCFG cache r3 /* * Call sys_init, it should never return. */ sys_start: /head.s mov pc, r3 r3 PC r3 r3 r0 r0 ATPCS r0 r0 bios_main() bios_main() bios.c return (unsigned char *)_rom_base; /bios.c BIOS bootloader head.s bl bios_main BIOS c bios_mian() bios.c c linux/gnu

15 bios.c 3.2 BIOS bios-dyh bios.c unsigned char *bios_main(void) { struct system_table_struct *system_table; /bios.c unsigned long startup_mode; int i, ch; system_table = (struct system_table_struct *)(_rom_base + system_table_offset); sys_init(system_table, _rom_base, DRAM_BASE); console_init(); printf("\r\n\r\n"); printf("compex BIOS for SAMSUNG S3C4510B v1.20 (build 0801)\r\n\r\n"); printf("modified by duyunhai for 'ARM study report 003'\r\n"); biosapi_init(); printf("\r\n"); startup_mode = bios_startup_mode(); if (startup_mode == BOOT_MENU) { startup_mode = menu(system_table); return (unsigned char *)_rom_base; //return to head.s with _rom_base in r0 bl bios_main bios bootloader struct system_table_struct system_table; /bios.c struct system_table_struct *system_table; struct system_table_struct bios.h struct system_table_struct { /bios.h

16 unsigned short vendor_id; unsigned short device_id; unsigned short sub_vendor_id; unsigned short sub_device_id; unsigned long rev; unsigned long bios_size; unsigned long system_table_size; unsigned long partition_table_offset; unsigned long partition_table_size; unsigned long sys_reg_base; unsigned long sys_clock; unsigned long ext_clock; struct sys_rom_cfg rom_table[6]; struct sys_dram_cfg dram_table[4]; unsigned long ext_base; struct sys_ext_cfg ext_table[4]; struct sys_iop_cfg iop; struct sys_uart_cfg uart[2]; struct sys_eth_cfg eth; struct sys_ne2000_cfg ne2000; struct sys_uart16550_cfg uart16550; struct sys_pc97338_cfg pc97338; unsigned long startup_mode; unsigned long tftp_ipaddr; ; BIOS rom_table,dram_table 2.2 param.tbl combine

17 BIOS param.tbl struct system_table_struct /imgtools/param/param.c 2.2 param.c bootloader /imgtools/param/param.c #define COMPEX_VENDOR_ID 0x11F6 #define IRE201_DEVICE_ID 0x8000 #define NP15B_DEVICE_ID 0x8001 #define BTE201_DEVICE_ID 0x8002 #define NONE_DEVICE_ID 0x0000 struct system_table_struct system_table = { bios_size: 0xc000, #ifdef IRE201 vendor_id: device_id: COMPEX_VENDOR_ID, IRE201_DEVICE_ID, sub_vendor_id: COMPEX_VENDOR_ID, sub_device_id: IRE201_DEVICE_ID, #endif #ifdef NP15B vendor_id: COMPEX_VENDOR_ID, device_id: NP15B_DEVICE_ID, sub_vendor_id: COMPEX_VENDOR_ID, sub_device_id: NP15B_DEVICE_ID, #endif #ifdef BTE201 vendor_id: device_id: COMPEX_VENDOR_ID, BTE201_DEVICE_ID, #endif sub_vendor_id: COMPEX_VENDOR_ID, sub_device_id: BTE201_DEVICE_ID, #ifdef SNDS100 vendor_id: device_id: COMPEX_VENDOR_ID, NONE_DEVICE_ID,

18 #endif sub_vendor_id: COMPEX_VENDOR_ID, sub_device_id: NONE_DEVICE_ID, rev: 0, sys_reg_base: sys_clock: ext_clock: 0x03ff0000, fmclk_mhz, 0xffffffff, #ifdef IRE201 rom_table: {{0x , 16, 0x , //rom0 is flash with 2M=1M*16bit {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , #endif dram_table: {{0x , 32, 0x , //sdram is 16M=4M*32bit #ifdef NP15B rom_table: {0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {{0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , #endif dram_table: #ifdef BTE201 rom_table: {{0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {{0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x ,

19 dram_table: #endif #ifdef SNDS100 rom_table: {{0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {{0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , #endif dram_table: {{0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , system_table_size: sizeof(struct system_table_struct), partition_table_offset: partition_table_size: 0x0000f000, sizeof(struct partition_table_struct), ext_base: 0x03fd0000, ext_table: {{ 32, 0x00000fff, { 32, 0x00000fff, { 32, 0x00000fff, { 32, 0x00000fff, iop: {0x , 0x2ad00300, ~0x , uart: {{0x , 0, 0, 0, 0, 0, 0, {0x , 1, 0, 0, 0, 0, 0, eth: {0x , {0x00, 0x80, 0x48, 0x88, 0x00, 0x00, ne2000: {0x , 0, {0x00, 0x80, 0x48, 0x88, 0x00, 0x01, uart16550: {0x , 1, , pc97338: {0x , 1, ; startup_mode: tftp_ipaddr: BOOT_MENU, 0xd34156c0,//

20 4510b sys_reg_base rom_table dram_table iop uart eth tftp_ipaddr 4510b datasheet ROM SDRAM #ifdef IRE201 rom_table: {{0x , 16, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , {0x , 8, 0x , #endif dram_table: {{0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , {0x , 32, 0x , BIOS IRE201 rom_table bios.h struct sys_rom_cfg { unsigned long size; unsigned long width; unsigned long flags; /bios.h ; size rom width flags flash 2M 16 flags datasheet 5 ROM BANK dram_table bios.h rom_table 16 SDRAM 32 SDRAM 16M 32 param.tbl /imgtools/param/param.c int main() /imgtools/param/param.c

21 { FILE *f; f = fopen("param.tbl", "wb"); fwrite((char *)(&system_table), 1, sizeof(struct system_table_struct), f); fclose(f); f = fopen("mbr.bin", "wb"); fwrite((char *)(&partition_table), 1, sizeof(struct partition_table_struct), f); fclose(f); return 0; /imgtools/param/param.c struct system_table_struct /bios.c system_table = (struct system_table_struct *)(_rom_base + system_table_offset); _rom_base + system_table_offset BIOS + _rom_base system_table_offset head.s system_table_offset:.long _rom_base:.long SYSTEM_TABLE_OFFSET stext /head.s system_table_offset SYSTEM_TABLE_OFFSET SYSTEM_TABLE_OFFSET config.h BIOS BIOS BIOS system_table sys_init(system_table, _rom_base, DRAM_BASE); bios.c sys_init( ) /bios.c /bios.c int sys_init(struct system_table_struct *system_table, unsigned long rom_base, unsigned long

22 dram_base) { typedef int (SYSINIT)(struct system_table_struct *, unsigned long, unsigned long); SYSINIT *sys_init_ptr; memcpy((char *)SRAM_BASE, sysinit_data, 1024 * 3); sys_init_ptr = (SYSINIT *)SRAM_BASE; sys_init_ptr(system_table, rom_base, dram_base); return 0; BIOS SDRAM DRAM_BASE system_table sysinit linux/gnu sysinit_data bios.c extern const unsigned char sysinit_data[]; sysinit_data[] sysinit.c sysinit_data sysinit.c sysinit_data[] sysinit sysinit.text 0x03FE0000 0x03FE0000 SRAM_BASE 4510b RAM SRAM sysinit_data[] SRAM_BASE bin2c sysinit BIOS sys_init_ptr sysinit 0x03FE0000 0x03FE0000 sys_init_ptr 0x03FE0000 sysinit sysinit sysinit.c BIOS 3.3 sysinit SRAM_BASE sysinit head.s.globl stext.section ".text" stext: b sys_init /sysinit/head.s

23 sysinit.c sys_init( ) system_table param.tbl extdbwth datasheet rom sdram ROM base = rom_base; for (i = 0; i < 6; i++) { sys_regs.romcon[i] = (system_table->rom_table[i].flags & ~0x3ffffc00) (((base + system_table->rom_table[i].size) & 0x03ff0000) << 4) ((base & 0x03ff0000) >> 6); base += system_table->rom_table[i].size; /sysinit/sysinit.c 6 romcon base system_table->rom_table[i].size base = rom_base; BIOS _rom_base=0x flash 16M system_table->rom_table[i].size system_table param.tbl datasheet rom ~0x3ffffc ROM Bank Next Pointer (((base + system_table->rom_table[i].size) & 0x03ff0000) << 4) 16 datasheet 64k 16 4 ((base + system_table->rom_table[i].size) & 0x03ff0000) ROM Bank Next Pointer ROM Bank Next Pointer SDRAM base = dram_base; /sysinit/sysinit.c

24 for (i = 0; i < 4; i++) { sys_regs.dramcon[i] = (system_table->dram_table[i].flags & ~0x3ffffc00) (((base + system_table->dram_table[i].size) & 0x03ff0000) << 4) ((base & 0x03ff0000) >> 6); base += system_table->dram_table[i].size; SDRAM ROM outl() outl(sys_regs.extdbwth, EXTDBWTH); outl(sys_regs.romcon[0], ROMCON0); outl(sys_regs.romcon[1], ROMCON1); outl(sys_regs.romcon[2], ROMCON2); outl(sys_regs.romcon[3], ROMCON3); outl(sys_regs.romcon[4], ROMCON4); outl(sys_regs.romcon[5], ROMCON5); outl(sys_regs.dramcon[0], DRAMCON0); outl(sys_regs.dramcon[1], DRAMCON1); outl(sys_regs.dramcon[2], DRAMCON2); outl(sys_regs.dramcon[3], DRAMCON3); outl(sys_regs.refextcon, REFEXTCON); /sysinit/sysinit.c outl() board.h #define VPchar *(volatile unsigned char *) #define outl(data, addr) (VPint(addr) = (data)) /board.h I/O 3.4 bios_main() sys_init(system_table, _rom_base, DRAM_BASE);

25 console_init(); /bios.c console.c int console_init(void) { outl(0x03, ULCON0); outl(0x09, UCON0); outl(0x1a0, UBRDIV0); //57600 N 8 /console.c return 0; console_init ULCON0 UCON0 UBRDIV0 0 datasheet printf printf console.c c 3.4 biosapi biosapi API bios API biosapi sysinit int biosapi_init(void) { unsigned char *inbuf; unsigned long insize; unsigned char *outbuf; unsigned long outsize; struct biosapi_init_struct init_param; BIOSCALL *fp; /bios.c inbuf = (unsigned char *)biosapi_data; outbuf = (unsigned char *)BIOS_API_ADDR; insize = 0x7fffffff; outsize = 0x7fffffff; gunzip(inbuf, &insize, outbuf, &outsize); init_param.rom_base = _rom_base;

26 init_param.dram_base = DRAM_BASE; init_param.system_table_offset = system_table_offset; fp = (BIOSCALL *)outbuf; return (*fp)(0, (unsigned long)&init_param); // Init BIOS call inbuf = (unsigned char *)biosapi_data; biosapi sysinit biosapi.c.ld Makefile outbuf = (unsigned char *)BIOS_API_ADDR; sysinit sysinit biosapi BIOS_API_ADDR config.h BIOS_API_ADDR biosapi.text biospai outbuf BIOS_API_ADDR gunzip(inbuf, &insize, outbuf, &outsize); outbuf biospai outbuf fp = (BIOSCALL *)outbuf; return (*fp)(0, (unsigned long)&init_param); /bios.c biosapi head.s biospai.globl stext.section ".text" stext: b bios_call_internal /biosapi/head.s biosapi biosapi.c bios_call_internal int bios_call_internal(unsigned long id, unsigned long arg) { switch (id) { case BIOSCALL_INIT: bios_call_init((struct biosapi_init_struct *)arg); break; /biosapi/biosapi.c

27 ID bios arg ID 0 BIOSCALL_INIT bios_call_init((struct biosapi_init_struct *)arg); bios_call_init config_table config_table system_table system_table config_table flash API bioscall.c bioscall.c API int bios_call(unsigned long id, unsigned long arg) { BIOSCALL *bios_call_ptr = (BIOSCALL *)BIOS_API_ADDR; return bios_call_ptr(id, arg); /bioscall.c bioscall.c bios_call() id arg BIOS biosapi BIOS_API_ADDR biosapi.c int bios_call_internal(unsigned long id, unsigned long arg) id. 3.5 BIOS bios_main() startup_mode = bios_startup_mode(); if (startup_mode == BOOT_MENU) { startup_mode = menu(system_table); return (unsigned char *)_rom_base; //return to head.s with _rom_base in r0 /bios.c Hayden Luo BIOS BIOS menu(system_table) BIOS > > menu bios-dyh /bios.c int menu(struct system_table_struct *system_table) { int select, partition_num = 0;

28 unsigned long input_data; unsigned long i; unsigned long linux_origin=0x ; while (1) { select = main_menu(system_table); if (select == BOOT_LOAD_FIRMWARE) { char*)(linux_origin+i); for(i=0;i<1024*1024*2;i++) { *(volatile unsigned char*)(0x8000+i)=*(volatile unsigned asm( " break; ); ldr r14, =0x ; mov PC, r14; " switch (select) { case BOOT_UPDATE_BIOS: load_tftp(select, partition_num); break; case BOOT_UPDATE_FIRMWARE: printf("sorry,this function is not complement\r\n\n\n"); break; case BOOT_LOAD_PROGRAM: { uart_receive(); break; case BOOT_BIOS_SETUP: printf("sorry,this function is not complement\r\n\n\n"); break; default: break;

29 return select; main_menu(system_table) bios-dyh BIOS uart_rec dram uart_rec BIOS sysinit tftp uclinux BOOT_LOAD_FIRMWARE image.ram flash flash 0x image 0x8000 0x8000 uclinux BOOT_UPDATE_BIOS tftp image.ram sdram 0x8000 ram BOOT_UPDATE_FIRMWARE bootloader bios-dyh BOOT_LOAD_PROGRAM sdram tftp V2.2 BOOT_BIOS_SETUP uclinux main_menu(system_table) 3.7 select tftp uart_rec switch (select) { /bios.c case BOOT_UPDATE_BIOS: load_tftp(select, partition_num); break; case BOOT_UPDATE_FIRMWARE: printf("sorry,this function is not complement\r\n\n\n"); break; case BOOT_LOAD_PROGRAM: { uart_receive();

30 break; case BOOT_BIOS_SETUP: printf("sorry,this function is not complement\r\n\n\n"); break; sysinit tftp twentyone tftp uart_rec BIOS V2.2 uclinux uclinux BIOS bootloader Hayden Luo Bios tftp twentyone ARM ARM ARM OPEN-JTAG ARM JTAG ARM ARM ARM OPEN-JTAG ARM ARM JTAG ARM JTAG OPEN-JTAG -

31 1 GNU/Linux ARM ARM 002 ARM 002 Object Object.o ARM 002 object elf object elf.rel<section name> section head.o.rel.text entry 1 relocation

32 1 readelf head.o rel.text elf object symbol table symbol table symbol table elf.symtab object symbol table head.o symol Symbol table Symbol table rel<.section>

33 2 readelf head.o symol table object.rel<section> symbol table.rel<section> symbol table symbol table.rel<section> symbol table 1 head.s bl bios_main bios.c bios_main head.o bios.o

head.o bios_main 00000000 bios.o symbol table bios_main LD.o.o bios.o.o symol table symol table bios symol table.

34 head.o bios_main bios.o symbol table bios_main LD.o.o bios.o.o symol table symol table bios symol table.o symol table readelf a bios bios_main head.o bl bios_main 3 bios_main readelf bios symol table 2 bin2c c sysinit bin2c c sysinit

$*/ const unsigned char sysinit_data[]= { 0x1e, 0x00, 0x00, 0xea, 0x0d, 0xc0, 0xa0, 0xe1, 0x00, 0xd8, 0x2d, 0xe9, 0x04, 0xb0, 0x4c, 0xe2, 0x08, 0xd0, 0x4d, 0xe2, 0x10, 0x00, 0x0b, 0xe5, 0x10, 0x30,$

35 BIOS bin2c c * autogenerated file -- DO NOT EDIT! */ const unsigned char sysinit_data[]= { 0x1e, 0x00, 0x00, 0xea, 0x0d, 0xc0, 0xa0, 0xe1, 0x00, 0xd8, 0x2d, 0xe9, 0x04, 0xb0, 0x4c, 0xe2, 0x08, 0xd0, 0x4d, 0xe2, 0x10, 0x00, 0x0b, 0xe5, 0x10, 0x30, 0x1b, 0xe5, 0x10, 0x00, 0x53, 0xe3, /* Note: 1460 characters output */ /* end of file */ /sysinit.c sysinit_data[] bios.ld c bios sysinit.o object elf 4 readelf sysinit.o symol table

36 .o sysinit_data bios.c bios sysinit_data sysinit_data 5 5 readelf bios symol table

基于Hayden Luo Bios的BootLoader源代码级分析.doc

基于Hayden Luo Bios的BootLoader源代码级分析.doc Hayden Luo Bios BootLoader GNU tools ARM ARM 002 2004-5-12 ARM 001 MySComm4510b ARM ADS1.2 ADW ARM Windwos ARM linux uclinux linux Bootloader linux ARM linux GNU ARM linux 99 linux linux C++ gcc makefile