3.1 ARM汇编编程概述

1. 汇编编程

为什么要学习汇编

1). Bootloader初始化

2). Linux kernel

3). 高效

2. ARM汇编分类

1. ARM标准汇编：ARM公司得汇编器适合在Windows平台下使用

2. GNU汇编：适用于GNU交叉编译工具链中的汇编器，适合Linux开发平台

3. 汇编程序框架

.section .data

    <初始化的数据>

.setction .bss

    <未初始化的数据>

.setction .text

.gobal _start

_start

    <汇编代码>

程序入口在_start

.text

.gobal _start

__start:

建立汇编程序环境

[root@cfm880 ~]# cd /home/S3-ARM/

[root@cfm880 S3-ARM]# makdir Part3

-bash: makdir: command not found

[root@cfm880 S3-ARM]# mkdir Part3

[root@cfm880 S3-ARM]# cd Part3

[root@cfm880 Part3]# mkdir lesson1

[root@cfm880 Part3]# chmod 777 ./

[root@cfm880 Part3]# cd lesson1/

[root@cfm880 lesson1]# chmod 777 ./

[root@cfm880 lesson1]# ls

[root@cfm880 lesson1]# vim start.S

.text

.global _start

_start:

mov r1, #1

mov r2, #2

mov r3, #3

[root@cfm880 lesson1]# vim Makefile

all:start.o

arm-linux-ld -Ttext 0x50008000 -o start.elf $^

%.o:%.S

arm-linux-gcc -g -o $@ $^ -c

clean:

rm *.o *.elft

链接地址为什么是0x50008000而不是0x50000000

双击

# tiny6410_config

# connect to the J-Link gdb server

target remote localhost:2331

# Set JTAG speed to 30 kHz

monitor endian little

monitor speed 30

# Reset the target

monitor reset

monitor sleep 10

#

# CPU core initialization (to be done by user)

#

# Set the processor mode

monitor reg cpsr = 0xd3

#config MMU

#flush v3/v4 cache

monitor cp15 7, 7, 0, 0 = 0x0

#/* flush v4 TLB */

monitor cp15 8, 7, 0, 0 = 0x0

#disable MMU stuff and caches

monitor cp15 1, 0, 0, 0 =0x1002

#Peri port setup

monitor cp15 15, 2, 0, 4 = 0x70000013

#disable watchdog

monitor MemU32 0x7e004000 = 0x00000000

monitor sleep 10

#disable interrupt

monitor MemU32 0x71200014 = 0x00000000

monitor MemU32 0x71300014 = 0x00000000

monitor MemU32 0x7120000C = 0x00000000

monitor MemU32 0x7130000C = 0x00000000

monitor MemU32 0x71200F00 = 0x00000000

monitor MemU32 0x71300F00 = 0x00000000

#set clock

monitor MemU32 0x7e00f900 = 0x0000801e

monitor MemU32 0x7e00f000 = 0x0000ffff

monitor MemU32 0x7e00f004 = 0x0000ffff

monitor MemU32 0x7e00f020 = 0x01043310

monitor MemU32 0x7e00f00C = 0xc2150601

monitor MemU32 0x7e00f010 = 0xc2150601

monitor MemU32 0x7e00f024 = 0x00000003

monitor MemU32 0x7e00f014 = 0x00200102

monitor MemU32 0x7e00f018 = 0x00000000

monitor MemU32 0x7e00f01C = 0x14000007

#config sdram

monitor MemU32 0x7e00f120 = 0x00000008

monitor MemU32 0x7e001004 = 0x00000004

monitor MemU32 0x7e001010 = 0x0000040f

monitor MemU32 0x7e001014 = 0x00000006

monitor MemU32 0x7e001018 = 0x00000001

monitor MemU32 0x7e00101c = 0x00000002

monitor MemU32 0x7e001020 = 0x00000006

monitor MemU32 0x7e001024 = 0x0000000a

monitor MemU32 0x7e001028 = 0x0000000c

monitor MemU32 0x7e00102c = 0x0000018f

monitor MemU32 0x7e001030 = 0x0000000c

monitor MemU32 0x7e001034 = 0x00000002

monitor MemU32 0x7e001038 = 0x00000002

monitor MemU32 0x7e00103c = 0x00000002

monitor MemU32 0x7e001040 = 0x00000002

monitor MemU32 0x7e001044 = 0x00000013

monitor MemU32 0x7e001048 = 0x00000013

monitor MemU32 0x7e00100C = 0x00010012

monitor MemU32 0x7e00104C = 0x00000b45

monitor MemU32 0x7e001200 = 0x000150f8

monitor MemU32 0x7e001304 = 0x00000000

monitor MemU32 0x7e001008 = 0x000c0000

monitor MemU32 0x7e001008 = 0x00000000

monitor MemU32 0x7e001008 = 0x00040000

monitor MemU32 0x7e001008 = 0x00040000

monitor MemU32 0x7e001008 = 0x000a0000

monitor MemU32 0x7e001008 = 0x00080032

monitor MemU32 0x7e001004 = 0x00000000

# Setup GDB for faster downloads

#set remote memory-write-packet-size 1024

set remote memory-write-packet-size 4096

set remote memory-write-packet-size fixed

monitor speed 12000

break _start

load

点击Debug