Jollen's Linux Consulting Services

Jollen’s Consulting

,
,

,
: www.jollen.org/consulting

Jollen’s Consulting
ta@jollen.org
[
]

Jollen’s Consulting Team

Linux - Jollen’s Consulting. www.jollen.org/consulting

# cd /
# tar zxvf arm-9tdmi-linux-gnu.tar.gz
( )

# export
PATH=/opt/crosstool/gcc-3.4.1-glibc-2.3.3/
arm-9tdmi-linux-gnu/bin/:$PATH
( )

(or)
# source ./armpath

– ipaddr

– serverip


jollen.org # printenv
bootdelay=3
ethaddr=10:10:ff:ff:ff:ff
ipaddr=192.168.1.10
serverip=192.168.1.1
netmask=255.255.255.0
stdin=serial
baudrate=115200
bootargs=root=/dev/ram0 rw console=ttyS0,115200
mem=64M ramdisk=16384
stdout=serial
stderr=serial

IP address 192.168.1.10 TFTP server IP address 192.168.1.1


jollen.org # set ipaddr 192.168.100.15
jollen.org # set serverip 192.168.100.14
jollen.org # saveenv
Saving Environment to Flash...
Un-Protected 1 sectors
Erasing Flash...Erasing sector 18 ... ok.
Erased 1 sectors
Writing to Flash... done
Protected 1 sectors


• loadAddress

• bootfilename


jollen.org # tftpboot 30F00000 uimage.img
jollen.org # tftpboot 32000000 urootfs.img
jollen.org # bootm 30F00000 32000000


src/cross.mk TOOL_TOP

TOOL_TOP = /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu


src/hello/ make

# make
[ -- Start to compile hello.c to hello.o -- ]
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/bin/arm-9tdmi-linux-gnu-gcc -nostdinc -I/opt/crosstool/
gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/include -I/opt/crosstool/gcc-3.4.1-glibc-2.3.3/
arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1/include -c hello.c
[ -- Start to link hello.o to hello.gdb -- ]
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/bin/arm-9tdmi-linux-gnu-gcc -Wl,-nostdlib -Wl,-L,/opt/
crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib -Wl,-L,/opt/crosstool/gcc-3.4.1-
glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1 -Wl,-rpath,/opt/crosstool/gcc-3.4.1-glibc-2.3.3/
arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib -Wl,-rpath,/lib -Wl,-rpath-link,/opt/crosstool/gcc-3.4.1-glibc-2.3.3/
arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib -nostartfiles -nodefaultlibs /opt/crosstool/gcc-3.4.1-glibc-2.3.3/
arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib/crt1.o /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/
arm-9tdmi-linux-gnu/lib/crti.o /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/
3.4.1/crtbegin.o hello.o /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1/
crtend.o /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib/crtn.o -lgcc -lgcc_eh -lc -
lgcc -lgcc_eh -o hello.gdb
[ -- Start to strip hello.gdb and produce hello -- ]
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/bin/arm-9tdmi-linux-gnu-strip -R .note -R .comment
hello.gdb -o hello


• hello

• hello.gdb

• hello.o hello.c

# arm-9tdmi-linux-gnu-objdump –x hello | more
(or)
# readelf –a hello | more


hello

• hello copy
# tftp –g –r hello 192.168.100.14 tftp (/tftpboot
in our example)
# chmod a+x ./hello
• Target IP
# ./hello
address ( ifconfig
)


•

•

•

•


#export PATH=/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-
linux-gnu/bin:$PATH

#arm-9tdmi-linux-gnu-gcc -g -nostdinc
-Os -Wall -mtune=arm9tdmi -march=armv4
-fomit-frame-pointer -fsigned-char -fPIC
-I/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/
arm-9tdmi-linux-gnu/include
-I/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/
gcc/arm-9tdmi-linux-gnu/3.4.1/include
-c hello.c


• -nostdinc

• -I
• -mtune=arm9tdmi

• -march=armv4

• -fomit-frame-pointer

• -fsigned-char
• -fPIC

• -Os
• -Wall
• -c
ld


arm-9tdmi-linux-gnu-ld
-nostdlib
-L /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib
-L /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1
-rpath-link /opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib
-o hello
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib/crt1.o
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib/crti.o
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1/
crtbegin.o
hello.o
/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/lib/gcc/arm-9tdmi-linux-gnu/3.4.1/crtend.o

/opt/crosstool/gcc-3.4.1-glibc-2.3.3/arm-9tdmi-linux-gnu/arm-9tdmi-linux-gnu/lib/crtn.o
-lgcc -lgcc_eh -lc -lgcc -lgcc_eh
arm-9tdmi-linux-gnu-strip -R .note -R .comment hello


• -L
• -o
• -lc libc
• -lgcc libgcc


‘｀


• TOOL_TOP

• GCC_LIB_PATH

• GLIBC_PATH
• CROSS_CFLAGS

• LDFLAGS

• LIBS
• LINK_S

• LINK_E


Makefile

Makefile make


– cross.mk


•

1.
2.
3.
4.


1. libmad-0.15.1b.tar.gz
cross.mk libmad-0.15.1b/
2.
libmad.cross
libmad-0.15.1b/
3.
4.


./configure
Makefile ./
configure

Makefile


cross.mk

cross.mk


• configure Makfile
configure

– CC

– AR

– LD

– AS

– STRIP

– RANLIB

– CFLAGS


• configure

– --prefix

– --host


Madplay
libid3tag
libmad
zlib

Building root filesystem (porting)
• standalone application (e.g. thttpd)
• software stacks (e.g. madplay project)
• software stacks with architectural consideration
(e.g. nano-X project)

Text

http://www.pconline.com.cn/pcedu/soft/gj/sys/0502/551643.html

Definition of a Software "bug":

Webster's New Collegiate Dictionary defines a "bug" as "an unexpected defect,
fault, flaw, or imperfection". We need to refine this definition since it is too
ambiguous. In the scope of this guarantee, a "bug", with respect to the
guaranteed software, is defined as "a defect, fault, flaw or imperfection which
causes the software to not operate as intended or to stop operating abruptly."

http://www.autocadstandards.org/autocadstandards/bugfree/default.htm

Boot-time


printk
kdb
kgdb
gdb + qemu


debug
printk remote debug N
kdb local debug N
kgdb remote debug Y
gdb + qemu remote debug Y


Linux kernel image

• arch/arm/boot/Image target kernel
• arch/arm/boot/zImage

• arch/arm/boot/uImage

• ./vmlinux ELF image


source level

printk kernel message --

kdb machine code --

gdb + qemu source code kernel w/ symbol table

kgdb source code kernel w/ symbol table


Debug Symbols

CONFIG_DEBUG_INFO = y

linux kernel for
s3c2410

http://www.jk2410.org/opensource/linux-2.6.20.4-jk2410.tar.bz2
http://www.jk2410.org/opensource/gcc-4.1.0-glibc-2.4.tar.bz2
$ make ARCH=arm CROSS_COMPILE=/opt/crosstool/gcc-4.1.0-glibc-2.4/arm-9tdmi-linux-gnueabi/bin/
arm-9tdmi-linux-gnueabi- menuconﬁg

$ make ARCH=arm CROSS_COMPILE=/opt/crosstool/gcc-4.1.0-glibc-2.4/arm-9tdmi-linux-gnueabi/bin/
arm-9tdmi-linux-gnueabi- uImage

$ make uImage

$ cd /usr/local/bin
$ sudo wget http://www.jk2410.org/opensource/pre-built/mkimage
$ chmod a+x mkimage

qemu
kernel

http://www.jk2410.org/opensource/qemu-jk2410-20070826.tar.gz

cpu/arm920t/start.S
• Setup vector table
CPU
• Set the CPU to SVC32 mode (reset)
• Relocate to RAM
• Setup stack
board/lart/memsetup.S
Board lib_arm/board.c
• Board initialize sequence
• start_armboot()
• Call main_loop()
board/<board>/*, eg.
main_loop(): main.c board/lart/lart.c


.globl _start
_start: b reset
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

_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

.balignl 16,0xdeadbeef


/*
* the actual reset code
*/

reset:
/*
* set the cpu to SVC32 mode
*/
mrs r0,cpsr
bic r0,r0,#0x1f
orr r0,r0,#0xd3
msr cpsr,r0
.
.
.
#ifdef CONFIG_INIT_CRITICAL
bl cpu_init_crit
#endif

Where memsetup be called.

relocate


cpu_init_crit:
/*
* flush v4 I/D caches
*/
mov r0, #0
mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */

/*
* disable MMU stuff and caches
*/
mrc p15, 0, r0, c1, c0, 0
bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
orr r0, r0, #0x00000002 @ set bit 2 (A) Align
orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
mcr p15, 0, r0, c1, c0, 0


/*
* before relocating, we have to setup RAM timing
* because memory timing is board-dependend, you will
* find a memsetup.S in your board directory.
*/
mov ip, lr
bl memsetup
mov lr, ip

mov pc, lr

Return to reset.
board/lart/memsetup.S


EM_BASE: .long 0xa0000000
MEM_START: .long 0xc0000000

#define MDCNFG 0x00
#define MDCAS0 0x04
#define MDCAS1 0x08
#define MDCAS2 0x0c
#define MSC0 0x10
#define MSC1 0x14
#define MECR 0x18

mdcas0: .long 0xc71c703f
mdcas1: .long 0xffc71c71
mdcas2: .long 0xffffffff
/* mdcnfg: .long 0x0bb2bcbf */
mdcnfg: .long 0x0334b22f @ alt
/* mcs0: .long 0xfff8fff8 */
msc0: .long 0xad8c4888 @ alt
mecr: .long 0x00060006
/* mecr: .long 0x994a994a @ alt */


.globl memsetup /* MDCNFG */
memsetup: ldr r1, mdcnfg
ldr r0, MEM_BASE str r1, [r0, #MDCNFG]
/* Setup the flash memory */
ldr r1, msc0 /* Set up PCMCIA space */
str r1, [r0, #MSC0] ldr r1, mecr
str r1, [r0, #MECR]
/* Set up the DRAM */
/* Load something to activate bank */
/* MDCAS0 */
ldr r1, mdcas0 ldr r1, MEM_START
str r1, [r0, #MDCAS0]
.rept 8
/* MDCAS1 */ ldr r0, [r1]
ldr r1, mdcas1 .endr

/* MDCAS2 */ /* everything is fine now */
ldr r1, mdcas2 mov pc, lr


relocate: /* relocate U-Boot to RAM */
adr r0, _start /* r0 <- current position of code */
ldr r1, _TEXT_BASE /* test if we run from flash or RAM */
cmp r0, r1 /* don't reloc during debug */
beq stack_setup

ldr r2, _armboot_start
ldr r3, _bss_start
sub r2, r3, r2 /* r2 <- size of armboot */
add r2, r0, r2 /* r2 <- source end address */

copy_loop:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end addreee [r2] */
ble copy_loop

stack_setup


/* Set up the stack */
stack_setup:
ldr r0, _TEXT_BASE /* upper 128 KiB: relocated uboot */
sub r0, r0, #CFG_MALLOC_LEN /* malloc area */
sub r0, r0, #CFG_GBL_DATA_SIZE /* bdinfo */
#ifdef CONFIG_USE_IRQ
sub r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
#endif
sub sp, r0, #12 /* leave 3 words for abort-stack */

clear_bss


clear_bss:
ldr r0, _bss_start /* find start of bss segment */
add r0, r0, #4 /* start at first byte of bss */
ldr r1, _bss_end /* stop here */
mov r2, #0x00000000 /* clear */

clbss_l:str r2, [r0] /* clear loop... */
add r0, r0, #4
cmp r0, r1
bne clbss_l
.
.
.

ldr pc, _start_armboot

_start_armboot: .word start_armboot

lib_arm/board.c


typedef int (init_fnc_t) (void);

init_fnc_t *init_sequence[] = {
cpu_init, /* basic cpu dependent setup */
board_init, /* basic board dependent setup */
interrupt_init, /* set up exceptions */
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 */
dram_init, /* configure available RAM banks */
display_dram_config,
NULL,
};


void start_armboot (void)
{
init_fnc_t **init_fnc_ptr;

for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) {
if ((*init_fnc_ptr)() != 0) {
hang ();
}
}
.
.
.
/* main_loop() can return to retry autoboot, if so just run it again. */
for (;;) {
main_loop ();
}
}


void start_linux(char *name,char *rdname)
{
void (*theKernel)(int zero, int arch, u32 params);
u32 exec_at = ZIMAGE_LOAD_ADDRESS;
u32 parm_at = DRAM_BASE + 0x100;
u32 machine_type;

load_image(name, exec_at); /* copy image into RAM */
load_image(rdname, INITRD_LOAD_ADDRESS);/* copy initial ramdisk image into RAM */
setup_tags(parm_at); /* sets up parameters */
machine_type = get_mach_type(); /* get machine type */
irq_shutdown(); /* stop irq */
cpu_op(CPUOP_MMUCHANGE, NULL); /* turn MMU off */

theKernel = (void (*)(int, int, u32))exec_at; /* set the kernel address */
theKernel(0, machine_type, parm_at); /* jump to kernel with register set */

/* NOT REACHED */
}


User Mode
Application

System Call Interface

Virture File System(VFS)
BSD socket

inet(AF_INET)
Kernel Mode Buffer Cache Network Subsystem
Transport(TCP,UDP)

Network(IP)
Character Block Network
Device Driver Device Driver Device Driver

Device Interface

Physical Device (Hardware)
Hardware

Source: Jollen Linux (Revision 5)


Source: Jollen Linux (Revision 5)


Jollen Chen <jollen@jollen.org>

Jollen's Consulting Embedded Linux

Openmoko Openmoko
Openmoko
Android OS
Android Android

- Android
Android porting (s3c244x/s3c64x0) Linux Linux
Jollen - www.jollen.org/blog

www.jollen.org/consulting

Jollen's Linux Consulting Services

Recomendados

Recomendados

Más contenido relacionado

Destacado

Destacado (10)

Similar a Jollen's Linux Consulting Services

Similar a Jollen's Linux Consulting Services (20)

Más de Jollen Chen

Más de Jollen Chen (20)

Último

Último (20)

Jollen's Linux Consulting Services