kernel panic after VFS mount in FPGA board

[pcuser p]

Hi,
I'm doing kernel porting to arm926 based FPGA board,very minimal setup
(uart + timer only)
I'm getting kernel panic after cramfs root file system is mounted,I am
expecting to enter login prompt after root file system is mounted.

Below are the details

#define PLAT_PHYS_OFFSET       0x80000000 (with 128 MB SDRAM)
#define CONFIG_PAGE_OFFSET  0xc0000000


Physical memory : 128MB (0x80000000 to 88000000)

ZRELADDR = 0x80008000
PARAMS_PHYS = 0x80000100
INITRD_PHYS = 0x80800000

Kernel cmd line : mem=32M console=ttySAC0,115200 root=/dev/ram0
rootfstype=cramfs init=/linuxrc initrd=0x80800000,8M user_debug=31

executables in cramfs (/bin) are built with busy box with all libraries
statically linked.

*linuxrc init script*
#!/bin/sh**
/bin/echo "mount /etc as ramfs"
/bin/mount -n -t ramfs ramfs /etc
/bin/mount -n -t tmpfs tmpfs /tmp
exec /sbin/init

I tried  with this init script,but kernel is hanging without any message..
I changed it a bit as below, to see if it reads the init script

#!/bin/sh
/bin/echo "Entering Init script"

with this changes,I am expect to get print message "Entering Init script"
after cramfs is mounted,but I am getting panic message which is attached
below.
Can some one suggest how to fix this..


*Kernel message:*
*memory layout:*
  Virtual kernel memory layout:
    vector  : 0xffff0000 - 0xffff1000   (   4 kB)
    fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
    DMA     : 0xffc00000 - 0xffe00000   (   2 MB)
    vmalloc : 0xc2800000 - 0xf6000000   ( 824 MB)
    lowmem  : 0xc0000000 - 0xc2000000   (  32 MB)
    modules : 0xbf000000 - 0xc0000000   (  16 MB)
      .text : 0xc0008000 - 0xc0169000   (1412 kB)
      .init : 0xc0169000 - 0xc017d000   (  80 kB)
      .data : 0xc017e000 - 0xc018b720   (  54 kB)
       .bss : 0xc018b744 - 0xc019c6fc   (  68 kB)

RAMDISK: cramfs filesystem found at block 0
RAMDISK: Loading 5868KiB [1 disk] into ram disk... -
done.
VFS: Mounted root (cramfs filesystem) readonly on device 1:0.
Freeing init memory: 80K

*Panic message:*
Kernel panic - not syncing: Attempted to kill init!
Backtrace:
[<c000c378>] (dump_backtrace+0x0/0x10c) from [<c000c49c>]
(dump_stack+0x18/0x1c)
 r6:c1822000 r5:c018bb40 r4:c018bb60 r3:60000013
[<c000c484>] (dump_stack+0x0/0x1c) from [<c0017d3c>] (panic+0x64/0x1b0)
[<c0017cd8>] (panic+0x0/0x1b0) from [<c001b5d8>] (do_exit+0x2b8/0x6b4)
 r3:c0184294 r2:00000000 r1:00000001 r0:c014f394
 r7:c1822000
[<c001b320>] (do_exit+0x0/0x6b4) from [<c001bd3c>] (do_group_exit+0xd8/0xe0)
 r7:000000f8
[<c001bc64>] (do_group_exit+0x0/0xe0) from [<c001bd5c>]
(sys_exit_group+0x18/0x20)
 r4:0008eba4 r3:00000000
[<c001bd44>] (sys_exit_group+0x0/0x20) from [<c0009460>]
(ret_fast_syscall+0x0/0x2c)
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