[meta-xilinx] Kernel boot error: mount rootfs before init mmc

[Arno Steffens]

Hi,
using the Linux version 4.6.0-xilinx-v2016.3 kernel and have a problem.
My rootfs is on emmc. In general it works, but from time to time it ends up in a crash:
It seem it tries to mount rootfs before the emmc subsystem is initialised.
Is there any trick to get this stable working?

error case:
..
[    1.233167] Registering SWP/SWPB emulation handler
[    1.242996] VFS: Cannot open root device "mmcblk0gp0p1" or unknown-block(0,0): error -6
[    1.251041] Please append a correct "root=" boot option; here are the available partitions:
[    1.259342] 0100           32768 ram0  (driver?)
[    1.263925] 0101           32768 ram1  (driver?)
[    1.268525] 0102           32768 ram2  (driver?)
[    1.273126] 0103           32768 ram3  (driver?)
[    1.277732] 1f00             128 mtdblock0  (driver?)
[    1.282761] 1f01            4096 mtdblock1  (driver?)
[    1.287793] 1f02             512 mtdblock2 [    1.287803] mmc0: new high speed MMC card at address 0001

[    1.297155]  (driver?)
[    1.298318] mmcblk0: mmc0:0001 Q1J54A 0 B
[    1.303779] 1f03              64 mtdblock3  (driver?)
[    1.308562] mmcblk0boot0: mmc0:0001 Q1J54A partition 1 2.00 MiB
[    1.314714] 1f04              64 mtdblock4  (driver?)
[    1.318780] mmcblk0boot1: mmc0:0001 Q1J54A partition 2 2.00 MiB
[    1.325645] 1f05            3584 mtdblock5 [    1.328994] mmcblk0gp0: mmc0:0001 Q1J54A partition 4 1.82 GiB


working case:

[    1.219935] can: netlink gateway (rev 20130117) max_hops=1
[    1.225585] Registering SWP/SWPB emulation handler
[    1.229313] mmc0: new high speed MMC card at address 0001
[    1.242033] mmcblk0: mmc0:0001 Q1J54A 0 B
[    1.246281] mmcblk0boot0: mmc0:0001 Q1J54A partition 1 2.00 MiB
[    1.262402] mmcblk0boot1: mmc0:0001 Q1J54A partition 2 2.00 MiB
[    1.278452] mmcblk0gp0: mmc0:0001 Q1J54A partition 4 1.82 GiB
[    1.294347] mmcblk0rpmb: mmc0:0001 Q1J54A partition 3 512 KiB
[    1.302997]  mmcblk0gp0: p1 p2 p3
[    1.309002] EXT4-fs (mmcblk0gp0p1): INFO: recovery required on readonly filesystem
[    1.316558] EXT4-fs (mmcblk0gp0p1): write access will be enabled during recovery
[    1.400676] EXT4-fs (mmcblk0gp0p1): recovery complete
[    1.407487] EXT4-fs (mmcblk0gp0p1): mounted filesystem with ordered data mode. Opts: (null)
[    1.415798] VFS: Mounted root (ext4 filesystem) readonly on device 179:25.
[    1.423783] devtmpfs: mounted

Best regards
Arno