uboot/tools/mkimage工具詳解

u bo ot源代碼的tools/目錄下有mkimage工具，這個工具能夠用來製做不壓縮或者壓縮的多種可啓動映象文件。

mkimage在製做映象文件的時候，是在原來的可執行映象文件的前面加上一個0x40字節的頭，記錄參數所指定的信息，這樣uboot才能識別這個映象是針對哪一個CPU體系結構的，哪一個OS的，哪一種類型，加載內存中的哪一個位置， 入口點在內存的那個位置以及映象名是什麼

root@Glym:/tftpboot# ./mkimage
Usage: ./mkimage -l image
-l ==> list image header information
./mkimage -A arch -O os -T type -C comp -a addr -e ep -n name -d data_file[:data_file...] image
-A ==> set architecture to 'arch'
-O ==> set operating system to 'os'
-T ==> set image type to 'type'
-C ==> set compression type 'comp'
-a ==> set load address to 'addr' (hex)
-e ==> set entry point to 'ep' (hex)
-n ==> set image name to 'name'
-d ==> use image data from 'datafile'
-x ==> set XIP (execute in place)
參數說明：

-A 指定CPU的體系結構：

取值 表示的體系結構
alpha Alpha 
arm A RM 
x86 Intel x86
ia64 IA64
mips MIPS
mips64 MIPS 64 Bit
ppc PowerPC
s390 IBM S390
sh SuperH
sparc SPARC
sparc64 SPARC 64 Bit
m68k MC68000

-O 指定操做系統類型，能夠取如下值：
openbsd、netbsd、freebsd、4_4bsd、linux、svr四、esix、solaris、irix、sco、dell、ncr、lynxos、vxworks、psos、qnx、u-boot、rtems、artos

-T 指定映象類型，能夠取如下值：
standalone、kernel、ramdisk、multi、firmware、script、filesystem

-C 指定映象壓縮方式，能夠取如下值：
none 不壓縮
gzip 用gzip的壓縮方式
bzip2 用bzip2的壓縮方式

-a 指定映象在內存中的加載地址，映象下載到內存中時，要按照用mkimage製做映象時，這個參數所指定的地址值來下載

-e 指定映象運行的入口點地址，這個地址就是-a參數指定的值加上0x40（由於前面有個mkimage添加的0x40個字節的頭）

-n 指定映象名

-d 指定製做映象的源文件

 

U-BOOT下使用bootm引導內核方法

1、在開始以前先說明一下bootm相關的東西。

一、 首先說明一下，S 3C 2410架構下的bootm只對sdram中的內核鏡像文件進行操做(好像AT91架構提供了一段從flash複製內核鏡像的代碼， 不過針對s 3c 2410架構就沒有這段代碼，雖然能夠在u-boot下添加這段代碼，不過好像這個用處不大)，因此請確保你的內核鏡像下載到sdram 中，或者在bootcmd下把flash中的內核鏡像複製到sdram中。

二、-a參數後是內核的運行地址，-e參數後是入口地址。

三、
1）若是咱們沒用mkimage對內核進行處理的話，那直接把內核下載到0x30008000再運行就行，內核會自解壓運行（不過內核運行須要一個tag來傳遞參數，而這個tag建議是由bootloader提供的，在u-boot下默認是由bootm命令創建的）。
 
2）若是使用mkimage生成內核鏡像文件的話，會在內核的前頭加上了64byte的信息，供創建tag之用。bootm命令會首先判斷bootm xxxx 這個指定的地址xxxx是否與-a指定的加載地址相同。
(1)若是不一樣的話會從這個地址開始提取出這個64byte的頭部，對其進行分析，而後把去掉頭部的內核複製到-a指定的load地址中去運行之
(2)若是相同的話那就讓其原封不一樣的放在那，但-e指定的入口地址會推後64byte，以跳過這64byte的頭部。


2、好，接着介紹使用mkimage生成鏡像文件並下載運行的方法。

方法1、
一、首先，用u-boot/tools/mkimage這個工具爲你的內核加上u-boot引導所須要的文件頭，具體作法以下：
[root@localhost tftpboot]#mkimage -n 'linux- 2.6.14 ' -A arm -O linux -T kernel -C none -a 0x30008000 -e 0x30008000 -d zImage zImage.img
Image Name:   linux-2.6.14
Created:      Fri Jan 12 17:14:50 2007
Image Type:   ARM Linux Kernel Image (uncompressed)
Data Size:    1262504 Bytes = 1232.91 kB = 1.20 MB
Load Address: 0x30008000
Entry Point:  0x30008000

這裏解釋一下參數的意義： 
        -A ==> set architecture to 'arch'
        -O ==> set operating system to 'os'
        -T ==> set image type to 'type'
        -C ==> set compression type 'comp'
        -a ==> set load address to 'addr' (hex)
        -e ==> set entry point to 'ep' (hex)
        -n ==> set image name to 'name'
        -d ==> use image data from 'datafile'
        -x ==> set XIP (execute in place)

2 、下載內核 
U-Boot  1.1.3  (Jan 12 2007 - 16:16:36)

U-Boot code:  33F 80000 ->  33F 9BAC0  BSS: ->  33F 9FBAC
RAM Configuration:
Bank #0: 30000000 64 MB
Nor Flash: 512 kB
Nand Flash:  64 MB
In:    serial
Out:   serial
Err:   serial
Hit any key to stop autoboot:  0
sbc2410=>tftp 0x31000000 zImage.img         
TFTP from server 192.168.1.115; our IP address is 192.168.1.128
Filename 'zImage.img'.
Load address: 0x31000000
Loading: #################################################################
        #################################################################
        #################################################################
        ####################################################
done
Bytes transferred = 1263324 (1346dc hex) 

3.運行 

sbc2410=>bootm 0x31000000
## Booting image at 31000000 ...
  Image Name:   linun- 2.6.14  
  Image Type:   ARM Linux Kernel Image (uncompressed)
  Data Size:    1263260 Bytes =  1.2 MB
  Load Address: 30008000
  Entry Point:  30008000
  Verifying Checksum ... OK
OK

Starting kernel ...

Uncompressing Linux.............................................................Linux version  2.6.14  (root@luofuchong) (gcc version 3.4.1) #21 Fri Oct 20 17:206CPU: ARM920Tid(wb) [41129200] revision 0 (ARMv4T)
Machine: SMDK2410
Memory policy: ECC disabled, Data cache writeback
CPU S 3C 2410A  (id 0x32410002)
S 3C 2410: core 202.800 MHz, memory 101.400 MHz, peripheral 50.700 MHz
S 3C 2410 Clocks, (c) 2004 Simtec Electronics
CLOCK: Slow mode (1.500 MHz), fast, MPLL on, UPLL on
USB Control, (c) 2006 sbc2410
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists
Kernel command line: console="ttySAC0" root="/dev/nfs" nfsroot="192".168.1.115:/frien"irq: clearing subpending status 00000002
PID hash table entries: 512 (order: 9, 8192 bytes)
timer tcon="00500000", tcnt a509, tcfg 00000200,00000000, usec 00001e 4c
Console: colour dummy device 80x30
Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
Memory: 64MB = 64MB total
Memory: 62208KB available (1924K code, 529K data, 108K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
softlockup thread 0 started up.
NET: Registered protocol family 16
S 3C 2410: Initialising architecture
SCSI subsystem initialized
usbcore: registered new driver usbfs
usbcore: registered new driver hub
S 3C 2410 DMA Driver, (c) 2003-2004 Simtec Electronics
DMA channel 0 at c4800000, irq 33
DMA channel 1 at c4800040, irq 34
DMA channel 2 at c4800080, irq 35
DMA channel 3 at c 48000c 0, irq 36
NetWinder Floating Point Emulator V0.97 (double precision)
devfs:  2004-01-31  Richard Gooch ( rgooch@atnf.csiro.au )
devfs: devfs_debug: 0x0
devfs: boot_options: 0x1
yaffs Oct 18 2006 12:39:51 Installing.
Console: switching to colour frame buffer device 30x40
fb0: s 3c 2410fb frame buffer device
fb1: Virtual frame buffer device, using 1024K of video memory
led driver initialized
s 3c 2410 buttons successfully loaded
s 3c 2410_serial0 at MMIO 0x50000000 (irq = 70) is a S 3C 2410
s 3c 2410_serial1 at MMIO 0x50004000 (irq = 73) is a S 3C 2410
s 3c 2410_serial2 at MMIO 0x50008000 (irq = 76) is a S 3C 2410
io scheduler noop registered
io scheduler anticipatory registered
io scheduler deadline registered
io scheduler cfq registered
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
usbcore: registered new driver ub
Cirrus Logic CS 8900A  driver for Linux (Modified for SMDK2410)
eth0: CS 8900A  rev E at 0xe0000300 irq="53", no eeprom , addr: 08: 0:3E:26: 0A :5B
S 3C 24XX NAND Driver, (c) 2004 Simtec Electronics
s 3c 2410-nand: mapped registers at c4980000
s 3c 2410-nand: timing: Tacls 10ns, Twrph0 30ns, Twrph1 10ns
NAND device: Manufacturer ID: 0xec, Chip ID: 0x76 (Samsung NAND 64MiB 3,3V 8-bi)Scanning device for bad blocks
Bad eraseblock 1884 at 0x01d70000
Creating 4 MTD partitions on "NAND 64MiB 3,3V 8-bit":
0x00000000-0x00020000 : "vivi"
0x00020000-0x00030000 : "param"
0x00030000-0x00200000 : "kernel"
0x00200000-0x04000000 : "root"
usbmon: debugfs is not available
s 3c 2410-ohci s 3c 2410-ohci: S 3C 24XX OHCI
s 3c 2410-ohci s 3c 2410-ohci: new USB bus registered, assigned bus number 1
s 3c 2410-ohci s 3c 2410-ohci: irq 42, io mem 0x49000000
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
Initializing USB Mass Storage driver...
usbcore: registered new driver usb-storage
USB Mass Storage support registered.
usbcore: registered new driver usbmouse
drivers/usb/input/usbmouse.c: v1.6:USB HID Boot Protocol mouse driver
mice: PS/2 mouse device common for all mice
s 3c 2410 TouchScreen successfully loaded
UDA1341 audio driver initialized
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 4096 (order: 2, 16384 bytes)
TCP bind hash table entries: 4096 (order: 2, 16384 bytes)
TCP: Hash tables configured (established 4096 bind 4096)
TCP reno registered
TCP bic registered
NET: Registered protocol family 1
IP-Config: Complete:
     device=eth0, addr="192".168.1.128, mask="255".255.255.0, gw="192".168.1.1,
    host="luofuchong", domain=, nis-domain=(none),
    bootserver="192".168.1.1, rootserver="192".168.1.115, rootpath=
Looking up port of RPC 100003/2 on 192.168.1.115
Looking up port of RPC 100005/1 on 192.168.1.115
VFS: Mounted root (nfs filesystem).
Mounted devfs on /dev
Freeing init memory: 108K
init started:  BusyBox v1.1.3 (2006.09.20-14:52+0000) multi-call binary
Starting pid 696, console /dev/tts/0: '/etc/init.d/rcS'

Please press Enter to activate this console.

方法2、
一、首先，用u-boot/tools/mkimage這個工具爲你的內核加上u-boot引導所須要的文件頭，具體作法以下：
[root@localhost tftpboot]#mkimage -n 'linux- 2.6.14 ' -A arm -O linux -T kernel -C none -a 0x30008000 -e 0x30008040 -d zImage zImage.img
Image Name:   linux-2.6.14
Created:      Fri Jan 12 17:14:50 2007
Image Type:   ARM Linux Kernel Image (uncompressed)
Data Size:    1262504 Bytes = 1232.91 kB = 1.20 MB
Load Address: 0x30008000
Entry Point:  0x30008040
 

2 、下載內核 
U-Boot  1.1.3  (Jan 12 2007 - 16:16:36)

U-Boot code:  33F 80000 ->  33F 9BAC0  BSS: ->  33F 9FBAC
RAM Configuration:
Bank #0: 30000000 64 MB
Nor Flash: 512 kB
Nand Flash:  64 MB
In:    serial
Out:   serial
Err:   serial
Hit any key to stop autoboot:  0
sbc2410=>tftp 0x30008000 zImage.img         
TFTP from server 192.168.1.115; our IP address is 192.168.1.128
Filename 'zImage.img'.
Load address: 0x30008000
Loading: #################################################################
        #################################################################
        #################################################################
        ####################################################
done
Bytes transferred = 1263324 (1346dc hex) 

3.運行 

sbc2410=>bootm 0x30008000
## Booting image at 30008000 ...
   Image Name:   linux- 2.6.14
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    1261056 Bytes =  1.2 MB
   Load Address: 30008000
   Entry Point:  30008040
   Verifying Checksum ... OK
   XIP Kernel Image ... OK