注：
u-boot使用的是打上：
上keety大侠提供的补丁生成的u-boot-1.1.3
这段时间不断有人问我u-boot启动内核的问题，记得在上次提供的u-boot源码中提到了go的方案，不过其实u-boot本来有一种更好的方案：bootm
花了不少时间，查看了论坛上的帖子，其中从这么一个贴中找到解决方法：
现在可以用bootm引导内核了，可能方法不一定是最好的，但起码是可用的，现把解决方法介绍如下：
1、首先，用u-boot/tools/mkimage这个工具为你的内核加上u-boot引导所需要的文件头，具体做法如下：
[root@localhost tftpboot]#mkimage -A arm -O linux -T kernel -C none -a 0x30000 -e 0x30008000 -d zImage zImage.img
Image Name:
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: 0x00030000
Entry Point: 0x30008000
这里解释一下参数的意义：
-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)
特别注意的是：
-a后接的是加载地址，也就是你内核的内核在flash中的存放地址（按我的理解）
-e后接的是运行地址，在sdram中运行内核的话一般是0x30008000
2、下载内核
U-Boot 1.1.3 (Jan 12 2007 - 16:16:36)
U-Boot code: 33F80000 -> 33F9BAC0 BSS: -> 33F9FBAC
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 = 1262568 (1343e8 hex)
sbc2410=> nand erase 30000 1d0000
NAND erase: device 0 offset 196608, size 1900544 ... OK
sbc2410=> nand write 30008000 30000 1d0000
NAND write: device 0 offset 196608, size 1900544 ... 1900544 bytes written: OK
3、最后，设置一下内核启动所需要的参数：
sbc2410=> setenv bootargs noinitrd root=/dev/mtdblock/3 console=ttySAC0
sbc2410=> bootcmd=nand read 0x30008000 0x30000 0x1d0000;bootm 0x30008000
sbc2410=> saveenv
Saving Environment to NAND...
Erasing Nand...Writing to Nand... done
4、重新复位，启动信息如下：
U-Boot 1.1.3 (Jan 12 2007 - 16:16:36)
U-Boot code: 33F80000 -> 33F9BAC0 BSS: -> 33F9FBAC
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
NAND read: device 0 offset 196608, size 1900544 ... 1900544 bytes read: OK
## Booting image at 30008000 ...
Image Name:
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 1262504 Bytes = 1.2 MB
Load Address: 00030000
Entry Point: 30008000
Verifying Checksum ... OK
OK
Starting kernel ...
Uncompressing Linux.............................................................Linux version 2.6.14 () (gcc version 3.4.1) #2 Fri Ja7CPU: ARM920Tid(wb) [41129200] revision 0 (ARMv4T)
Machine: SMDK2410
Memory policy: ECC disabled, Data cache writeback
CPU S3C2410A (id 0x32410002)
S3C2410: core 202.800 MHz, memory 101.400 MHz, peripheral 50.700 MHz
S3C2410 Clocks, (c) 2004 Simtec Electronics
CLOCK: Slow mode (1.500 MHz), fast, MPLL on, UPLL on
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: noinitrd root=/dev/mtdblock/3 console=ttySAC0
irq: clearing subpending status 00000002
PID hash table entries: 512 (order: 9, 8192 bytes)
timer tcon=00500000, tcnt a509, tcfg 00000200,00000000, usec 00001e4c
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 (1925K 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
USB Control, (c) 2006 sbc2410
S3C2410: Initialising architecture
SCSI subsystem initialized
usbcore: registered new driver usbfs
usbcore: registered new driver hub
S3C2410 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 c48000c0, irq 36
NetWinder Floating Point Emulator V0.97 (double precision)
devfs: 2004-01-31 Richard Gooch ()
devfs: devfs_debug: 0x0
devfs: boot_options: 0x1
yaffs Jan 11 2007 23:38:14 Installing.
s3c2410-lcd s3c2410-lcd: no platform data for lcd, cannot attach
s3c2410-lcd: probe of s3c2410-lcd failed with error -22
Console: switching to colour frame buffer device 80x25
fb0: Virtual frame buffer device, using 1024K of video memory
s3c2410_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2410
s3c2410_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2410
s3c2410_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2410
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 CS8900A driver for Linux (Modified for SMDK2410)
eth0: CS8900A rev E at 0xe0000300 irq=53, no eeprom , addr: 08: 0:3E:26:0A:5B
S3C24XX NAND Driver, (c) 2004 Simtec Electronics
s3c2410-nand: mapped registers at c4980000
s3c2410-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
s3c2410-ohci s3c2410-ohci: S3C24XX OHCI
s3c2410-ohci s3c2410-ohci: new USB bus registered, assigned bus number 1
s3c2410-ohci s3c2410-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.
mice: PS/2 mouse device common for all mice
ts: Compaq touchscreen protocol output
s3c2410 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
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
NET: Registered protocol family 1
................................
可以看到，内核已经跑起来了，大功告成！
