AM3354
解決"VFS: Cannot open root device "mmcblk0p2" or unknown-block"
如果使用者的rootfs是放在SDCard的話，在Kernel啟動的過程可能會遇到如下問題：
[ 1.581573] mmc0: host does not support reading read-only switch. assuming write-enable. [ 1.593841] mmc0: new high speed SD card at address e624 [ 1.600067] mmcblk0: mmc0:e624 SU02G 1.84 GiB [ 2.972686] mmcblk0: error -84 transferring data, sector 0, nr 8, cmd response 0x900, card status 0xb00 [ 2.982543] mmcblk0: retrying using single block read [ 2.993041] mmcblk0: error -84 transferring data, sector 4, nr 4, cmd response 0x900, card status 0x0 [ 3.002685] end_request: I/O error, dev mmcblk0, sector 4 [ 3.011505] Buffer I/O error on device mmcblk0, logical block 0 [ 3.019653] mmcblk0: unable to read partition table [ 3.079772] VFS: Cannot open root device "mmcblk0p2" or unknown-block(179,2) [ 3.087158] Please append a correct "root=" boot option; here are the available partitions:
解法很簡單，只要再Kernel的.config檔案中，把開機的選項加入boot_delay=32 rootdelay=10 rootwait，然後重新編譯即可。
CONFIG_CMDLINE="root=/dev/mmcblk0p2 boot_delay=32 rootdelay=10 rootwait console=ttyO0,115200"