boot from sd/mmc card error

when I boot a kernel uImage from MMC card, I got an error as below:

Waiting 1sec before mounting root device…
mmcblk0: mmc0:bf07 SD02G 1921024KiB
mmcblk0: p1 p2
EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
VFS: Mounted root (ext2 filesystem).
Freeing init memory: 136K
Warning: unable to open an initial console.
Buffer I/O error on device mmcblk0p2, logical block 297808

and I set u-boot bootargs as :

setenv bootargs ‘display=15 mem=128M console=ttyS0,115200n8 noinitrd root=/dev/mmcblk0p2 rw root rootfstype=ext2 rootdelay=1 nohz=off’

my first partition is FAT32, my second partition is ext2 with root filesystem in.

what do the error mean to us? how to do with this problem?

Which board is this, I read ttyS0 as console, it should be ttyS2 -isn't it ?

I have seen similar errors when the card is bad, try to mount the same
card over a ramdisk. Boot the kernel with ramdisk, then mount the
partition. This should give some hints on issues with card or fs.