[FS#376] r2770-af79fdb breaks Mikrotik RB433UAH

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - duvi (duvi) 

Attached to Project - LEDE Project
Summary - r2770-af79fdb breaks Mikrotik RB433UAH
Task Type - Bug Report
Category - Kernel
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - High
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - After upgrading to [[https://github.com/lede-project/source/commit/af79fdbe4af32a287798b579141204bda056b8aa|r2770-af79fdb]] or above, Mikrotik RB433UAH doesn't boot anymore.

Starting from r2770-af79fdb:
[    3.006764] m25p80 spi0.0: pm25lv512 (64 Kbytes)
[    3.011388] Creating 4 MTD partitions on "spi0.0":
[    3.016221] 0x000000000000-0x00000000b000 : "routerboot"
[    3.024182] 0x00000000b000-0x00000000c000 : "hard_config"
[    3.031071] 0x00000000d000-0x00000000f000 : "bios"
[    3.037359] 0x00000000f000-0x000000010000 : "soft_config"
[    3.044352] NAND flash driver for RouterBoard 4xx series version 0.2.0
[    3.050970] rb4xx_nand: write cmd failed, err=-22
[    3.055685] rb4xx_nand: write cmd failed, err=-22
[    3.060387] rb4xx_nand: write cmd failed, err=-22
[    3.065112] rb4xx_nand: write cmd failed, err=-22
[    3.069816] rb4xx_nand: write cmd failed, err=-22
[    3.074562] nand: second ID read did not match ff,00 against 00,10
[    3.080733] nand: No NAND device found
[    3.092586] IP17xx: Found IP175D at ag71xx-mdio.0:00
[    3.098246] libphy: ag71xx_mdio: probed
[    3.416179] ag71xx ag71xx.1: connected to PHY at ag71xx-mdio.0:04 [uid=02430d80, driver=Generic PHY]
[    3.425944] eth0: Atheros AG71xx at 0xba000000, irq 5, mode:RMII
[    3.829843] ag71xx ag71xx.0: connected to PHY at ag71xx-mdio.0:00 [uid=02430d80, driver=IC+ IP17xx]
[    3.839534] eth1: Atheros AG71xx at 0xb9000000, irq 4, mode:MII
[    3.845662] usbcore: registered new interface driver dvb_usb_az6007
[    3.853987] NET: Registered protocol family 10
[    3.862540] NET: Registered protocol family 17
[    3.867116] bridge: automatic filtering via arp/ip/ip6tables has been deprecated. Update your scripts to load br_netfilter if you need th
is.
[    3.879831] 8021q: 802.1Q VLAN Support v1.8
[    3.884273] rb: no calibration data found
[    3.890813] VFS: Cannot open root device "(null)" or unknown-block(0,0): error -6
[    3.898339] Please append a correct "root=" boot option; here are the available partitions:
[    3.906686] 1f00              44 mtdblock0  (driver?)
[    3.911736] 1f01               4 mtdblock1  (driver?)
[    3.916792] 1f02               8 mtdblock2  (driver?)
[    3.921840] 1f03               4 mtdblock3  (driver?)
[    3.926897] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
[    3.936066] Rebooting in 1 seconds..

One commit earlier, r2769-e307259 still boots OK:
[    3.006723] m25p80 spi0.0: pm25lv512 (64 Kbytes)
[    3.011349] Creating 4 MTD partitions on "spi0.0":
[    3.016182] 0x000000000000-0x00000000b000 : "routerboot"
[    3.024143] 0x00000000b000-0x00000000c000 : "hard_config"
[    3.031033] 0x00000000d000-0x00000000f000 : "bios"
[    3.037317] 0x00000000f000-0x000000010000 : "soft_config"
[    3.044303] NAND flash driver for RouterBoard 4xx series version 0.2.0
[    3.051140] nand: device found, Manufacturer ID: 0xad, Chip ID: 0xdc
[    3.057495] nand: Hynix NAND 512MiB 3,3V 8-bit
[    3.061927] nand: 512 MiB, MLC, erase size: 256 KiB, page size: 2048, OOB size: 64
[    3.069509] Scanning device for bad blocks
[    3.430630] Creating 3 MTD partitions on "NAND 512MiB 3,3V 8-bit":
[    3.436819] 0x000000000000-0x000000040000 : "booter"
[    3.443078] 0x000000040000-0x000000400000 : "kernel"
[    3.449533] 0x000000400000-0x000020000000 : "rootfs"
[    3.456563] mtd: device 6 (rootfs) set to be root filesystem
[    3.462878] mtdsplit: no squashfs found in "rootfs"
[    3.475655] IP17xx: Found IP175D at ag71xx-mdio.0:00
[    3.481213] libphy: ag71xx_mdio: probed
[    3.806176] ag71xx ag71xx.1: connected to PHY at ag71xx-mdio.0:04 [uid=02430d80, driver=Generic PHY]
[    3.815952] eth0: Atheros AG71xx at 0xba000000, irq 5, mode:RMII
[    4.219832] ag71xx ag71xx.0: connected to PHY at ag71xx-mdio.0:00 [uid=02430d80, driver=IC+ IP17xx]
[    4.229537] eth1: Atheros AG71xx at 0xb9000000, irq 4, mode:MII
[    4.235663] usbcore: registered new interface driver dvb_usb_az6007
[    4.243966] NET: Registered protocol family 10
[    4.252493] NET: Registered protocol family 17
[    4.257074] bridge: automatic filtering via arp/ip/ip6tables has been deprecated. Update your scripts to load br_netfilter if you need th
is.
[    4.269790] 8021q: 802.1Q VLAN Support v1.8
[    4.274232] rb: no calibration data found
[    4.280782] yaffs: dev is 32505862 name is "mtdblock6" ro
[    4.286231] yaffs: passed flags ""
[    4.519127] VFS: Mounted root (yaffs filesystem) readonly on device 31:6.
[    4.526981] Freeing unused kernel memory: 244K (80483000 - 804c0000)

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=376