U-Boot and Kernel not recognizing ubi file system

[JohnKlug]

I am using Yocto Zeus with 5.4 kernel and u-boot 2020.04.

I build the ubi image, and the only message I see from ubinize is:

ubinize: volume size was not specified in section "ubifs", assume minimum to fit image.

In U-Boot:

=> ubi part nandrootfs
ubi0: attaching mtd7
ubi0: scanning is finished
ubi0: volume table was restored
ubi0: volume 0 ("imx6ull14x14evk-rootfs") re-sized from 290 to 1916 LEBs
ubi0: attached mtd7 (name "nandrootfs", size 490 MiB)
ubi0: PEB size: 262144 bytes (256 KiB), LEB size: 253952 bytes
ubi0: min./max. I/O unit sizes: 4096/4096, sub-page size 4096
ubi0: VID header offset: 4096 (aligned 4096), data offset: 8192
ubi0: good PEBs: 1956, bad PEBs: 4, corrupted PEBs: 0
ubi0: user volume: 1, internal volumes: 1, max. volumes count: 128
ubi0: max/mean erase counter: 1/0, WL threshold: 4096, image sequence number: 159654406
ubi0: available PEBs: 0, total reserved PEBs: 1956, PEBs reserved for bad PEB handling: 36

I know the device has 4 blocks marked bad.

Layout:

=> ubi info layout
Volume information dump:
        vol_id          0
        reserved_pebs   1916
        alignment       1
        data_pad        0
        vol_type        3
        name_len        22
        usable_leb_size 253952
        used_ebs        1916
        used_bytes      486572032
        last_eb_bytes   253952
        corrupted       0
        upd_marker      0
        skip_check      0
        name            imx6ull14x14evk-rootfs
Volume information dump:
        vol_id          2147479551
        reserved_pebs   2
        alignment       1
        data_pad        0
        vol_type        3
        name_len        13
        usable_leb_size 253952
        used_ebs        2
        used_bytes      507904
        last_eb_bytes   2
        corrupted       0
        upd_marker      0
        skip_check      0
        name            layout volume

Mount result:

=> ubifsmount ubi0:imx6ull14x14evk-rootfs
UBIFS error (ubi0:0 pid 0): ubifs_read_node: bad node type (255 but expected 6)
UBIFS error (ubi0:0 pid 0): ubifs_read_node: bad node at LEB 0:0, LEB mapping status 0
Not a node, first 24 bytes:Error reading superblock on volume 'ubi0:imx6ull14x14evk-rootfs' errno=-22!
ubifsmount - mount UBIFS volume

Usage:
ubifsmount <volume-name>
    - mount 'volume-name' volume

Kernel:

[    2.495649] ubi0: default fastmap pool size: 95
[    2.500225] ubi0: default fastmap WL pool size: 47
[    2.505216] ubi0: attaching mtd6
[    3.056892] ubi0: scanning is finished
[    3.072096] ubi0 warning: ubi_eba_init: cannot reserve enough PEBs for bad PEB handling, reserved 34, need 36
[    3.085277] ubi0: attached mtd6 (name "nandrootfs", size 490 MiB)
[    3.091421] ubi0: PEB size: 262144 bytes (256 KiB), LEB size: 253952 bytes
[    3.098413] ubi0: min./max. I/O unit sizes: 4096/4096, sub-page size 4096
[    3.105337] ubi0: VID header offset: 4096 (aligned 4096), data offset: 8192
[    3.112327] ubi0: good PEBs: 1956, bad PEBs: 4, corrupted PEBs: 0
[    3.118481] ubi0: user volume: 1, internal volumes: 1, max. volumes count: 128
[    3.125852] ubi0: max/mean erase counter: 2/0, WL threshold: 4096, image sequence number: 159654406
[    3.134966] ubi0: available PEBs: 0, total reserved PEBs: 1956, PEBs reserved for bad PEB handling: 34
[    3.144319] ubi0: background thread "ubi_bgt0d" started, PID 114
 ...
[    3.343148]  (driver?)
[    3.349749] 1f06          501760 mtdblock6 
[    3.349755]  (driver?)
[    3.356337] No filesystem could mount root, tried: 
[    3.356341]  ubifs
[    3.361228] 
[    3.364747] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[    3.373038] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]---

[JohnKlug · Accepted solution]

I found the following useful information on ubifs:

http://www.linux-mtd.infradead.org/faq/ubifs.html#L_mkfubifs 

In order to create the ubifs successfully you need parameters set for the NAND.  I was able to boot from SD card and inspect my NAND with:

mtdinfo /dev/mtd0 -u

I was then able to set the following ubifs parameters in my conf/machine/${MACHINE} file:

MKUBIFS_ARGS = "-m 4096 -e 253952 -c 1932"
UBINIZE_ARGS = "-p 256KiB -m 4096"

[igorpadykov]

Hi John

for that issue one can recheck nand programming procedure, for example

https://variwiki.com/index.php?title=Yocto_NAND_Flash_Burning

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-To-use-NAND-boot-on-i-MX6UL-EVK-boar...

Best regards
igor