I'm working on an embedded system that has onboard eMMC. I know the hardware works (i can access it through u-boot); so the issue AFAIK is with my linux setup. My board boots linux consistenly when I use rootfs=NFS or rootfs=ramdisk. My current goal is to create a rootfs on my eMMC.
Here is my current state:
eMMC works fine. I am able to put kernel and ramdisk images there and boot from them.
I am able to successfully set up a partition using "fdisk /dev/mmcblk0". Output from "fdisk -l" shows:
# fdisk -l
Disk /dev/mmcblk0: 7801 MB, 7801405440 bytes
4 heads, 16 sectors/track, 238080 cylinders
Units = cylinders of 64 * 512 = 32768 bytes
Device Boot Start End Blocks Id System
/dev/mmcblk0p1 769 238080 7593984 83 Linux
So, as far as I can tell, this is good. The partition is set.
Then I do mkfs.ext3 /dev/mmcblk0p1, and that succeeds.
Then things go south...
The next step should be to mount /dev/mmcblk0p1 so that I can then copy rootfs to it (right?); however this fails...
# mkdir /tmp/mountpoint
# mount -t ext3 /dev/mmcblk0p1 /tmp/mountpoint
mount: mounting /dev/mmcblk0p1 on /tmp/mountpoint failed: No such device
Obviously the /dev/mmcblk0p1 device does exist (refer to output of fdisk -l above). The output of ls -l /dev/mmc* shows:
# ls -l /dev/mmc*
brw------- 1 root root 179, 0 Jan 1 00:00 /dev/mmcblk0
brw------- 1 root root 179, 8 Jan 1 00:00 /dev/mmcblk0boot0
brw------- 1 root root 179, 16 Jan 1 00:00 /dev/mmcblk0boot1
brw------- 1 root root 179, 1 Jan 1 00:03 /dev/mmcblk0p1
brw------- 1 root root 179, 24 Jan 1 00:00 /dev/mmcblk0rpmb
I tried chmod 777 on these, but that didn't matter.
Any idea why this would be failing? I'm currently digging into busybox's mount.c, but not making much progress.