Hi, All

I'm newbie on ARM_LinuX. My ARM board is very close to the offical AT91SAM9260-EK.

Via buildroot, I tgot all necessary bin file: a bootstrap, a u-boot.bin, a uImage(linux kernel), and a filesystem image.

And I flash all them into dataflash, but linux kernel panic...
No filesystem could mount root, tried: ext2 cramfs vfat
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,0)

I use sam-ba to write "buildroot/output/images/rootfs.ext2" into dataflash, Is this right?


====
my u-boot env:
U-Boot 2010.06-00438-gd0d3502-dirty (Feb 10 2011 - 22:01:24)

DRAM: 64 MiB
NAND: No NAND device found!!!
0 MiB
DataFlash:AT45DB642
Nb pages: 8192
Page Size: 1056
Size= 8650752 bytes
Logical address: 0xD0000000
Area 0: D0000000 to D00041FF (RO) Bootstrap
Area 1: D0004200 to D00083FF Environment
Area 2: D0008400 to D0041FFF (RO) U-Boot
Area 3: D0042000 to D0251FFF Kernel
Area 4: D0252000 to D083FFFF FS
In: serial
Out: serial
Err: serial
Net: macb0
macb0: Starting autonegotiation...
macb0: Autonegotiation complete
macb0: link up, 100Mbps full-duplex (lpa: 0x45e1)
Hit any key to stop autoboot: 0
U-Boot>
U-Boot> printenv
bootcmd=cp.b 0xD0042000 0x22000000 0x210000; bootm
baudrate=115200
ethaddr=04:25:fe:ed:00:18
ipaddr=10.175.196.18
serverip=10.175.196.221
gatewayip=10.175.196.1
netmask=255.255.255.0
ethact=macb0
bootdelay=2
bootargs=root=/dev/mtdblock0
stdin=serial
stdout=serial
stderr=serial

Environment size: 278/16892 bytes


====
my kernel trace log:
U-Boot> boot
## Booting kernel from Legacy Image at 22000000 ...
Image Name: Linux-2.6.33
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 1290068 Bytes = 1.2 MiB
Load Address: 20008000
Entry Point: 20008000
Verifying Checksum ... OK
Loading Kernel Image ... OK
OK

Starting kernel ...

Uncompressing Linux... done, booting the kernel.
Linux version 2.6.33 (marco@thinkpad) (gcc version 4.3.5 (Buildroot 2011.02-git-00438-gd0d3502-d1
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
CPU: VIVT data cache, VIVT instruction cache
Machine: Atmel AT91SAM9260-EK
Memory policy: ECC disabled, Data cache writeback
Clocks: CPU 198 MHz, master 99 MHz, main 18.432 MHz
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256
Kernel command line: root=/dev/mtdblock0
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: 62212KB available (2344K code, 195K data, 112K init, 0K highmem)
* RCU implementation.
NR_IRQS:192
AT91: 96 gpio irqs in 3 banks
Console: colour dummy device 80x30
console [tty0] enabled
console [ttyS0] enabled
Calibrating delay loop... 98.91 BogoMIPS (lpj=494592)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
NET: Registered protocol family 16
bio: create slab <bio-0> at 0
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
Switching to clocksource pit
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
NetWinder Floating Point Emulator V0.97 (double precision)
JFFS2 version 2.2. (NAND) �© 2001-2006 Red Hat, Inc.
msgmni has been set to 121
io scheduler noop registered (default)
Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
brd: module loaded
loop: module loaded
ssc ssc.0: Atmel SSC device at 0xc4868000 (irq 14)
atmel_spi atmel_spi.0: Atmel SPI Controller at 0xfffc8000 (irq 12)
mtd_dataflash spi0.1: AT45DB642x (8448 KBytes) pagesize 1056 bytes (OTP)
MACB_mii_bus: probed
eth0: Atmel MACB at 0xfffc4000 irq 21 (04:25:fe:ed:00:18)
eth0: attached PHY driver [Generic PHY] (mii_bus:phy_addr=ffffffff:00, irq=-1)
usbmon: debugfs is not available
ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
at91_ohci at91_ohci: AT91 OHCI
at91_ohci at91_ohci: new USB bus registered, assigned bus number 1
at91_ohci at91_ohci: irq 20, io mem 0x00500000
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
Initializing USB Mass Storage driver...
usbcore: registered new interface driver usb-storage
USB Mass Storage support registered.
mice: PS/2 mouse device common for all mice
rtc-at91sam9 at91_rtt.0: rtc core: registered at91_rtt as rtc0
IRQ 1/rtc0: IRQF_DISABLED is not guaranteed on shared IRQs
rtc-at91sam9 at91_rtt.0: rtc0: SET TIME!
i2c /dev entries driver
i2c-gpio i2c-gpio: using pins 55 (SDA) and 56 (SCL)
AT91SAM9 Watchdog: sorry, watchdog is disabled
at91_wdt: probe of at91_wdt failed with error -5
TCP cubic registered
NET: Registered protocol family 17
rtc-at91sam9 at91_rtt.0: hctosys: unable to read the hardware clock
List of all partitions:
1f00 8448 mtdblock0 (driver?)
No filesystem could mount root, tried: ext2 cramfs vfat
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,0)
Backtrace:
[<c0028b10>] (dump_backtrace+0x0/0x10c) from [<c01ec510>] (dump_stack+0x18/0x1c)
r7:00008000 r6:c3861000 r5:c0021a50 r4:c381bf60
[<c01ec4f8>] (dump_stack+0x0/0x1c) from [<c01ec550>] (panic+0x3c/0x130)
[<c01ec514>] (panic+0x0/0x130) from [<c0009130>] (mount_block_root+0x264/0x2bc)
r3:00000000 r2:00000020 r1:c381bf60 r0:c023b3b6
[<c0008ecc>] (mount_block_root+0x0/0x2bc) from [<c00091dc>] (mount_root+0x54/0x6c)
[<c0009188>] (mount_root+0x0/0x6c) from [<c0009360>] (prepare_namespace+0x16c/0x1d0)
r5:c0021a08 r4:c0287358
[<c00091f4>] (prepare_namespace+0x0/0x1d0) from [<c000862c>] (kernel_init+0xdc/0x110)
r5:c0020844 r4:c0287138
[<c0008550>] (kernel_init+0x0/0x110) from [<c003e72c>] (do_exit+0x0/0x5e4)
r5:00000000 r4:00000000