linux-2.6.39.3移植时NFS挂载出错相关解决

面是启动的信息，请求帮助，主机的nfs服务已开启，路径都是正常的，用别人做的内核可以启动nfs，用自己移植的就有找不到root的问题，这个问题我研究了好多天了


AM1808 initialization passed!
Booting TI User Boot Loader
  UBL Version: 1.65
  UBL Flashtype: NAND
Starting NAND Copy...
Valid magicnum, 0x55424CBB, found in block 0x00000006.
  DONE
Jumping to entry point at 0xC1080000.
Flash: ## Unknown flash on Bank 1 - Size = 0x00000000 = 0 MB
NAND: 256 MiB
SF: Detected S25FL064P with page size 256, total 8 MiB
In: serial
Out: serial
Err: serial
ARM Clock : 372000000 Hz
Net: Ethernet PHY: GENERIC @ 0x00
DaVinci-EMAC
Hit any key to stop autoboot: 0
Using DaVinci-EMAC device
TFTP from server 192.168.1.66; our IP address is 192.168.1.9
Filename 'uImage'.
Load address: 0xc0700000
Loading: #################################################################
  #################################################################
  ########
done
Bytes transferred = 2012208 (1eb430 hex)
## Booting kernel from Legacy Image at c0700000 ...
  Image Name: Linux-2.6.39.3
  Image Type: ARM Linux Kernel Image (uncompressed)
  Data Size: 2012144 Bytes = 1.9 MiB
  Load Address: c0008000
  Entry Point: c0008000
  Verifying Checksum ... OK
  Loading Kernel Image ... OK
OK

Starting kernel ...

Uncompressing Linux... done, booting the kernel.
Linux version 2.6.39.3 ([e-mail]) (gcc version 4.5.1 (Sourcery G++ Lite 2010.09-50) ) #22 PREEMPT Wed Jul 20 17:46:11 CST 2011
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
CPU: VIVT data cache, VIVT instruction cache
Machine: DaVinci DA850/OMAP-L138/AM18x EVM
Memory policy: ECC disabled, Data cache writeback
DaVinci da850/omap-l138/am18x variant 0x1
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256
Kernel command line: noinitrd root=/dev/nfs rw nfsroot=192.168.1.107:/home/shawzy/my_rootfs ip=192.168.1.9:192.168.1.107:192.168.1.1::255.255.255.0 console=ttyS2,115200n8 init=/linuxrc
PID hash table entries: 256 (order: -2, 1024 bytes)
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 64MB = 64MB total
Memory: 60748k/60748k available, 4788k reserved, 0K highmem
Virtual kernel memory layout:
  vector : 0xffff0000 - 0xffff1000 ( 4 kB)
  fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
  DMA : 0xff000000 - 0xffe00000 ( 14 MB)
  vmalloc : 0xc4800000 - 0xfea00000 ( 930 MB)
  lowmem : 0xc0000000 - 0xc4000000 ( 64 MB)
  modules : 0xbf000000 - 0xc0000000 ( 16 MB)
  .init : 0xc0008000 - 0xc0028000 ( 128 kB)
  .text : 0xc0028000 - 0xc03c61c0 (3705 kB)
  .data : 0xc03c8000 - 0xc03ed780 ( 150 kB)
SLUB: Genslabs=13, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
Preemptable hierarchical RCU implementation.
  RCU-based detection of stalled CPUs is disabled.
  Verbose stalled-CPUs detection is disabled.
NR_IRQS:245
Console: colour dummy device 80x30
Calibrating delay loop... 184.72 BogoMIPS (lpj=923648)
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
DaVinci: 144 gpio irqs
NET: Registered protocol family 16
casic_nand_pinmux 0
bio: create slab <bio-0> at 0
pca953x 1-0020: failed reading register
pca953x: probe of 1-0020 failed with error -121
pca953x 1-0021: failed reading register
pca953x: probe of 1-0021 failed with error -121
Switching to clocksource timer0_1
Switched to NOHz mode on CPU #0
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 2048 (order: 2, 16384 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
UDP hash table entries: 256 (order: 0, 4096 bytes)
UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
NET: Registered protocol family 1
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
RPC: Registered tcp NFSv4.1 backchannel transport module.
NetWinder Floating Point Emulator V0.97 (double precision)
EMAC: MII PHY configured, RMII PHY will not be functional
Installing knfsd (copyright (C) 1996 [e-mail]).
JFFS2 version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
msgmni has been set to 118
io scheduler noop registered (default)
start plist test
end plist test
Serial: 8250/16550 driver, 3 ports, IRQ sharing disabled
serial8250.0: ttyS0 at MMIO 0x1c42000 (irq = 25) is a 16550A
serial8250.0: ttyS1 at MMIO 0x1d0c000 (irq = 53) is a 16550A
serial8250.0: ttyS2 at MMIO 0x1d0d000 (irq = 61) is a 16550A
console [ttyS2] enabled
brd: module loaded
NAND device: Manufacturer ID: 0xec, Chip ID: 0xda (Samsung NAND 256MiB 3,3V 8-bit)
Creating 5 MTD partitions on "davinci_nand.1":
0x000000000000-0x000000020000 : "u-boot env"
0x000000020000-0x000000040000 : "UBL"
0x000000040000-0x0000000c0000 : "u-boot"
0x000000200000-0x000000600000 : "kernel"
0x000000600000-0x000010000000 : "filesystem"
davinci_nand davinci_nand.1: controller rev. 2.5
spi_davinci spi_davinci.1: DMA: supported
spi_davinci spi_davinci.1: DMA: RX channel: 18, TX channel: 19, event queue: 0
m25p80 spi1.0: found s25sl064a, expected m25p64
m25p80 spi1.0: s25sl064a (8192 Kbytes)
Creating 6 MTD partitions on "m25p80":
0x000000000000-0x000000010000 : "UBL"
0x000000010000-0x000000090000 : "U-Boot"
0x000000090000-0x0000000a0000 : "U-Boot-Env"
0x0000000a0000-0x000000320000 : "Kernel"
0x000000320000-0x000000720000 : "Filesystem"
0x0000007f0000-0x000000800000 : "MAC-Address"
spi_davinci spi_davinci.1: Controller at 0xfef0e000
davinci_mdio davinci_mdio.0: davinci mdio revision 1.5
davinci_mdio davinci_mdio.0: detected phy mask fffffffe
davinci_mdio.0: probed
davinci_mdio davinci_mdio.0: phy[0]: device 0:00, driver unknown
console [netcon0] enabled
netconsole: network logging started
i2c /dev entries driver
watchdog watchdog: heartbeat 60 sec
cpuidle: using governor ladder
cpuidle: using governor menu
TCP cubic registered
NET: Registered protocol family 17
Registering the dns_resolver key type
davinci_emac_probe: using random MAC addr: 0e:20:03:6e:c6:4a
davinci_mdio davinci_mdio.0: resetting idled controller
net eth0: attached PHY driver [Generic PHY] (mii_bus:phy_addr=0:00, id=7c0f1)
IP-Config: Guessing netmask 255.255.255.0
IP-Config: Complete:
  device=eth0, addr=192.168.1.9, mask=255.255.255.0, gw=192.168.1.1,
  host=255, domain=, nis-domain=255.255.0,
  bootserver=192.168.1.107, rootserver=192.168.1.107, rootpath=
PHY: 0:00 - Link is Up - 100/Full
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "nfs" or unknown-block(2,0)
Please append a correct "root=" boot option; here are the available partitions:
1f00 128 mtdblock0 (driver?)
1f01 128 mtdblock1 (driver?)
1f02 512 mtdblock2 (driver?)
1f03 4096 mtdblock3 (driver?)
1f04 256000 mtdblock4 (driver?)
1f05 64 mtdblock5 (driver?)
1f06 512 mtdblock6 (driver?)
1f07 64 mtdblock7 (driver?)
1f08 2560 mtdblock8 (driver?)
1f09 4096 mtdblock9 (driver?)
1f0a 64 mtdblock10 (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)
解决办法 ：

RMII驱动没有配置上，配置RMII 驱动