NFS Booting with BBB

Hi all, I’m trying to get my BBB to boot over tftp and NFS. Just about any information out there is dated and most tutorials are incomplete or cannot be modified to work on a BBB (or my 2 remaining braincells couldnt figure it out). So let me start off with what I have done on both the server and client side.

[SERVER]
I’m working on an Ubuntu 20.04 setup
# /etc/default/tftpd-hpa

TFTP_USERNAME=“tftp”
TFTP_DIRECTORY="/home/[my-user-name]/tftpboot"
TFTP_ADDRESS=":69"
TFTP_OPTIONS="–secure"

contents of /home/[my-user-name]/tftpboot/

tftpboot/
├── dtbs
│ └── am335x-boneblack.dtb
├── test.img
└── zImage

1 directory, 3 files

# /etc/exports

/home/[path-to workspace]/network-boot/rootfs *(rw,sync,no_root_squash,no_subtree_check)

contents of /home/[path-to workspace]/network-boot/rootfs

[path-to-workspace]/network-boot/rootfs/
├── bin
├── boot
├── core-image-minimal-beaglebone-yocto.ext4
├── dev
├── etc
├── home
├── init → bin/busybox
├── lib
├── media
├── mnt
├── proc
├── run
├── sbin
├── sys
├── tmp
├── usr
└── var

15 directories, 2 files

The files and folders in both directories were generated using Yocto. I have manually tested it out to make sure the build was successful and can boot. I also allowed port 69 and have restarted both services multiple times.

[CLIENT]
In the root directory of the base image of the BBB, there is a file named nfs-uEnv.txt. I’ve modified it as per the instructions in the file and renamed it as uEnv.txt

/uEnv.txt

##Rename as: uEnv.txt to boot via nfs

##https://www.kernel.org/doc/Documentation/filesystems/nfs/nfsroot.txt

##SERVER: sudo apt-get install tftpd-hpa
##SERVER:
##SERVER: zImage boot:
##SERVER: TFTP_DIRECTORY defined in /etc/default/tftpd-hpa
##SERVER: zImage/.dtb need to be located here:
##SERVER: TFTP_DIRECTORY/zImage
##SERVER: TFTP_DIRECTORY/dtbs/
.dtb
##SERVER:
##SERVER: uname_r boot:
##SERVER: TFTP_DIRECTORY defined in /etc/default/tftpd-hpa
##SERVER: Change TFTP_DIRECTORY to /NFSEXPORT/boot
##SERVER: TFTP_DIRECTORY/vmlinuz-${uname_r}
##SERVER: TFTP_DIRECTORY/dtbs/${uname_r}/*.dtb

##client_ip needs to be set for u-boot to try booting via nfs

client_ip=192.168.1.67

#u-boot defaults: uncomment and override where needed

server_ip=192.168.1.121
gw_ip=192.168.1.1
netmask=255.255.255.0
#hostname=
device=eth0
autoconf=off
root_dir=/home/[path-to workspace]/network-boot/rootfs
nfs_options=,vers=3
nfsrootfstype=ext4 rootwait fixrtc

##use uname_r= only if TFTP SERVER is setup for uname_r boot:
#uname_r=

Yet it does not boot, here is the output from the serial connection while trying to boot
[Serial Output]

U-Boot SPL 2019.04-00002-g07d5700e21 (Mar 06 2020 - 11:24:55 -0600)

Trying to boot from MMC2

Loading Environment from EXT4… Card did not respond to voltage select!

U-Boot 2019.04-00002-g07d5700e21 (Mar 06 2020 - 11:24:55 -0600), Build: jenkins-github_Bootloader-Builder-137

CPU : AM335X-GP rev 2.1

I2C: ready

DRAM: 512 MiB

No match for driver ‘omap_hsmmc’

No match for driver ‘omap_hsmmc’

Some drivers were not found

Reset Source: Power-on reset has occurred.

RTC 32KCLK Source: External.

MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1

Loading Environment from EXT4… Card did not respond to voltage select!

Board: BeagleBone Black

not set. Validating first E-fuse MAC

BeagleBone Black:

BeagleBone: cape eeprom: i2c_probe: 0x54:

BeagleBone: cape eeprom: i2c_probe: 0x55:

BeagleBone: cape eeprom: i2c_probe: 0x56:

BeagleBone: cape eeprom: i2c_probe: 0x57:

Net: eth0: MII MODE

cpsw, usb_ether

Press SPACE to abort autoboot in 0 seconds

board_name=[A335BNLT] …

board_rev=[00C0] …

Card did not respond to voltage select!

Card did not respond to voltage select!

Card did not respond to voltage select!

gpio: pin 56 (gpio 56) value is 0

gpio: pin 55 (gpio 55) value is 0

gpio: pin 54 (gpio 54) value is 0

gpio: pin 53 (gpio 53) value is 1

Card did not respond to voltage select!

Card did not respond to voltage select!

switch to partitions #0, OK

mmc1(part 0) is current device

Scanning mmc 1:1…

gpio: pin 56 (gpio 56) value is 0

gpio: pin 55 (gpio 55) value is 0

gpio: pin 54 (gpio 54) value is 0

gpio: pin 53 (gpio 53) value is 1

switch to partitions #0, OK

mmc1(part 0) is current device

gpio: pin 54 (gpio 54) value is 1

Checking for: /uEnv.txt …

1023 bytes read in 22 ms (44.9 KiB/s)

gpio: pin 55 (gpio 55) value is 1

Loaded environment from /uEnv.txt

Importing environment from mmc …

Checking if uenvcmd is set …

Checking if client_ip is set …

gpio: pin 56 (gpio 56) value is 1

Running nfsboot …

Booting from 192.168.1.121 …

cpsw Waiting for PHY auto negotiation to complete… done

link up on port 0, speed 100, full duplex

Using cpsw device

TFTP from server 192.168.1.121; our IP address is 192.168.1.67

Filename ‘zImage’.

Load address: 0x82000000

Loading: ###############T #########T #########################################

##############################T ######T #############################

######################################################T ##T #########

####################################T #T ##############T ##############

#########################T ####################T #######T #############

#################################################################

#################################################################

#####################################################T #######

82 KiB/s

done

Bytes transferred = 7553080 (734038 hex)

link up on port 0, speed 100, full duplex

Using cpsw device

TFTP from server 192.168.1.121; our IP address is 192.168.1.67

Filename ‘dtbs/am335x-boneblack.dtb’.

Load address: 0x88000000

Loading: #####

11.7 KiB/s

done

Bytes transferred = 62852 (f584 hex)

## Flattened Device Tree blob at 88000000

Booting using the fdt blob at 0x88000000

Loading Device Tree to 8ffed000, end 8ffff583 … OK

Starting kernel …

Booting Linux on physical CPU 0x0

Linux version 5.10.55-yocto-standard (oe-user@oe-host) (arm-poky-linux-gnueabi-gcc (GCC) 11.2.0, GNU ld (GNU Binutils) 2.37.20210721) #1 PREEMPT Wed Aug 4 02:33:59 UTC 2021

CPU: ARMv7 Processor [413fc082] revision 2 (ARMv7), cr=10c5387d

CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache

OF: fdt: Machine model: TI AM335x BeagleBone Black

Memory policy: Data cache writeback

cma: Reserved 16 MiB at 0x9e800000

Zone ranges:

Normal [mem 0x0000000080000000-0x000000009fefffff]

HighMem empty

Movable zone start for each node

Early memory node ranges

node 0: [mem 0x0000000080000000-0x000000009fefffff]

Initmem setup node 0 [mem 0x0000000080000000-0x000000009fefffff]

CPU: All CPU(s) started in SVC mode.

AM335X ES2.1 (sgx neon)

Built 1 zonelists, mobility grouping on. Total pages: 129666

Kernel command line: console=ttyO0,115200n8 root=/dev/nfs rw rootfstype=ext4 rootwait fixrtc nfsroot=192.168.1.121:/home/atakan/Desktop/Oruba/network-boot/rootfs,vers=3 ip=192.168.1.67:192.168.1.121:192.16

8.1.1:255.255.255.0::eth0:off

Dentry cache hash table entries: 65536 (order: 6, 262144 bytes, linear)

Inode-cache hash table entries: 32768 (order: 5, 131072 bytes, linear)

mem auto-init: stack:off, heap alloc:off, heap free:off

Memory: 483008K/523264K available (10240K kernel code, 1551K rwdata, 3900K rodata, 1024K init, 616K bss, 23872K reserved, 16384K cma-reserved, 0K highmem)

SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1

ftrace: allocating 40218 entries in 79 pages

ftrace: allocated 79 pages with 5 groups

rcu: Preemptible hierarchical RCU implementation.

rcu: RCU event tracing is enabled.

Trampoline variant of Tasks RCU enabled.

Rude variant of Tasks RCU enabled.

Tracing variant of Tasks RCU enabled.

rcu: RCU calculated value of scheduler-enlistment delay is 10 jiffies.

NR_IRQS: 16, nr_irqs: 16, preallocated irqs: 16

IRQ: Found an INTC at 0x(ptrval) (revision 5.0) with 128 interrupts

random: get_random_bytes called from start_kernel+0x310/0x54c with crng_init=0

TI gptimer clocksource: always-on /ocp/interconnect@44c00000/segment@200000/target-module@31000

sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 89478484971ns

clocksource: dmtimer: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 79635851949 ns

TI gptimer clockevent: 24000000 Hz at /ocp/interconnect@48000000/segment@0/target-module@40000

Console: colour dummy device 80x30

WARNING: Your ‘console=ttyO0’ has been replaced by ‘ttyS0’

This ensures that you still see kernel messages. Please

update your kernel commandline.

Calibrating delay loop… 996.14 BogoMIPS (lpj=4980736)

pid_max: default: 32768 minimum: 301

LSM: Security Framework initializing

Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)

Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)

CPU: Testing write buffer coherency: ok

CPU0: Spectre v2: using BPIALL workaround

Setting up static identity map for 0x80100000 - 0x80100060

rcu: Hierarchical SRCU implementation.

devtmpfs: initialized

VFP support v0.3: implementor 41 architecture 3 part 30 variant c rev 3

clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns

futex hash table entries: 256 (order: -1, 3072 bytes, linear)

pinctrl core: initialized pinctrl subsystem

NET: Registered protocol family 16

DMA: preallocated 256 KiB pool for atomic coherent allocations

l3-aon-clkctrl:0000:0: failed to disable

thermal_sys: Registered thermal governor ‘step_wise’

cpuidle: using governor ladder

cpuidle: using governor menu

hw-breakpoint: debug architecture 0x4 unsupported.

Serial: AMBA PL011 UART driver

Kprobes globally optimized

raid6: int32x8 gen() 170 MB/s

raid6: int32x8 xor() 105 MB/s

raid6: int32x4 gen() 199 MB/s

raid6: int32x4 xor() 117 MB/s

raid6: int32x2 gen() 367 MB/s

raid6: int32x2 xor() 202 MB/s

raid6: int32x1 gen() 367 MB/s

random: fast init done

raid6: int32x1 xor() 173 MB/s

raid6: using algorithm int32x1 gen() 367 MB/s

raid6: … xor() 173 MB/s, rmw enabled

raid6: using intx1 recovery algorithm

SCSI subsystem initialized

usbcore: registered new interface driver usbfs

usbcore: registered new interface driver hub

usbcore: registered new device driver usb

clocksource: Switched to clocksource dmtimer

NET: Registered protocol family 2

IP idents hash table entries: 8192 (order: 4, 65536 bytes, linear)

tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 4096 bytes, linear)

TCP established hash table entries: 4096 (order: 2, 16384 bytes, linear)

TCP bind hash table entries: 4096 (order: 2, 16384 bytes, linear)

TCP: Hash tables configured (established 4096 bind 4096)

UDP hash table entries: 256 (order: 0, 4096 bytes, linear)

UDP-Lite hash table entries: 256 (order: 0, 4096 bytes, linear)

NET: Registered protocol family 1

RPC: Registered named UNIX socket transport module.

RPC: Registered udp transport module.

RPC: Registered tcp transport module.

RPC: Registered tcp NFSv4.1 backchannel transport module.

hw perfevents: enabled with armv7_cortex_a8 PMU driver, 5 counters available

Initialise system trusted keyrings

workingset: timestamp_bits=14 max_order=17 bucket_order=3

NFS: Registering the id_resolver key type

Key type id_resolver registered

Key type id_legacy registered

Key type cifs.idmap registered

xor: measuring software checksum speed

arm4regs : 1274 MB/sec

8regs : 939 MB/sec

32regs : 1273 MB/sec

xor: using function: arm4regs (1274 MB/sec)

Key type asymmetric registered

Asymmetric key parser ‘x509’ registered

Block layer SCSI generic (bsg) driver version 0.4 loaded (major 250)

io scheduler mq-deadline registered

io scheduler kyber registered

gpiochip_add_data_with_key: GPIOs 0…31 (gpio-0-31) failed to register, -517

omap_gpio 44e07000.gpio: Could not register gpio chip -517

gpiochip_add_data_with_key: GPIOs 0…31 (gpio-0-31) failed to register, -517

omap_gpio 4804c000.gpio: Could not register gpio chip -517

gpiochip_add_data_with_key: GPIOs 0…31 (gpio-0-31) failed to register, -517

omap_gpio 481ac000.gpio: Could not register gpio chip -517

gpiochip_add_data_with_key: GPIOs 0…31 (gpio-0-31) failed to register, -517

omap_gpio 481ae000.gpio: Could not register gpio chip -517

debugfs: Directory ‘49000000.dma’ with parent ‘dmaengine’ already present!

edma 49000000.dma: TI EDMA DMA engine driver

pinctrl-single 44e10800.pinmux: 142 pins, size 568

Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled

44e09000.serial: ttyS0 at MMIO 0x44e09000 (irq = 20, base_baud = 3000000) is a 8250

printk: console [ttyS0] enabled

omap_rng 48310000.rng: Random Number Generator ver. 20

random: crng init done

brd: module loaded

mtdoops: mtd device (mtddev=name/number) must be supplied

libphy: Fixed MDIO Bus: probed

davinci_mdio 4a101000.mdio: davinci mdio revision 1.6, bus freq 1000000

libphy: 4a101000.mdio: probed

davinci_mdio 4a101000.mdio: phy[0]: device 4a101000.mdio:00, driver SMSC LAN8710/LAN8720

cpsw 4a100000.ethernet: initialized cpsw ale version 1.4

cpsw 4a100000.ethernet: ALE Table size 1024

cpsw 4a100000.ethernet: Detected MACID = a8:10:87:bb:c3:0a

am335x-phy-driver 47401300.usb-phy: supply vcc not found, using dummy regulator

am335x-phy-driver 47401b00.usb-phy: supply vcc not found, using dummy regulator

ehci_hcd: USB 2.0 ‘Enhanced’ Host Controller (EHCI) Driver

ehci-omap: OMAP-EHCI Host Controller driver

usbcore: registered new interface driver usb-storage

musb-hdrc musb-hdrc.1: MUSB HDRC host driver

musb-hdrc musb-hdrc.1: new USB bus registered, assigned bus number 1

hub 1-0:1.0: USB hub found

hub 1-0:1.0: 1 port detected

omap_rtc 44e3e000.rtc: registered as rtc0

omap_rtc 44e3e000.rtc: setting system clock to 2000-01-01T00:00:00 UTC (946684800)

i2c /dev entries driver

omap_wdt: OMAP Watchdog Timer Rev 0x01: initial timeout 60 sec

sdhci: Secure Digital Host Controller Interface driver

sdhci: Copyright(c) Pierre Ossman

sdhci-pltfm: SDHCI platform and OF driver helper

sdhci-omap 481d8000.mmc: supply vqmmc not found, using dummy regulator

usbcore: registered new interface driver usbhid

usbhid: USB HID core driver

u32 classifier

input device check on

Actions configured

NET: Registered protocol family 10

Segment Routing with IPv6

sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver

NET: Registered protocol family 17

Bridge firewalling registered

Key type dns_resolver registered

NET: Registered protocol family 40

oprofile: using arm/armv7

ThumbEE CPU extension supported.

omap_voltage_late_init: Voltage driver support not added

Loading compiled-in X.509 certificates

mmc1: SDHCI controller on 481d8000.mmc [481d8000.mmc] using External DMA

Key type ._fscrypt registered

Key type .fscrypt registered

Key type fscrypt-provisioning registered

Btrfs loaded, crc32c=crc32c-generic

Key type encrypted registered

OMAP GPIO hardware version 0.1

tps65217-pmic: Failed to locate of_node [id: -1]

mmc1: new high speed MMC card at address 0001

mmcblk1: mmc1:0001 M62704 3.56 GiB

mmcblk1boot0: mmc1:0001 M62704 partition 1 2.00 MiB

mmcblk1boot1: mmc1:0001 M62704 partition 2 2.00 MiB

mmcblk1rpmb: mmc1:0001 M62704 partition 3 512 KiB, chardev (249:0)

tps65217-bl: Failed to locate of_node [id: -1]

mmcblk1: p1

tps65217 0-0024: TPS65217 ID 0xe version 1.2

omap_i2c 44e0b000.i2c: bus 0 rev0.11 at 400 kHz

omap_i2c 4819c000.i2c: bus 2 rev0.11 at 100 kHz

omap_gpio 44e07000.gpio: Could not set line 6 debounce to 200000 microseconds (-22)

sdhci-omap 48060000.mmc: Got CD GPIO

sdhci-omap 48060000.mmc: supply vqmmc not found, using dummy regulator

mmc0: SDHCI controller on 48060000.mmc [48060000.mmc] using External DMA

tda998x 0-0070: found TDA19988

tilcdc 4830e000.lcdc: bound 0-0070 (ops tda998x_ops)

[drm] Initialized tilcdc 1.0.0 20121205 for 4830e000.lcdc on minor 0

tilcdc 4830e000.lcdc: [drm] Cannot find any crtc or sizes

printk: console [netcon0] enabled

netconsole: network logging started

tilcdc 4830e000.lcdc: [drm] Cannot find any crtc or sizes

cpsw 4a100000.ethernet: initializing cpsw version 1.12 (0)

SMSC LAN8710/LAN8720 4a101000.mdio:00: attached PHY driver [SMSC LAN8710/LAN8720] (mii_bus:phy_addr=4a101000.mdio:00, irq=POLL)

cpsw 4a100000.ethernet eth0: Link is Up - 100Mbps/Full - flow control off

IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready

IP-Config: Complete:

device=eth0, hwaddr=a8:10:87:bb:c3:0a, ipaddr=192.168.1.67, mask=255.255.255.0, gw=192.168.1.1

host=192.168.1.67, domain=, nis-domain=(none)

bootserver=192.168.1.121, rootserver=192.168.1.121, rootpath=

cfg80211: Loading compiled-in X.509 certificates for regulatory database

cfg80211: Loaded X.509 cert ‘sforshee: 00b28ddf47aef9cea7’

platform regulatory.0: Direct firmware load for regulatory.db failed with error -2

cfg80211: failed to load regulatory.db

VFS: Unable to mount root fs via NFS.

devtmpfs: mounted

Freeing unused kernel memory: 1024K

Run /sbin/init as init process

Run /etc/init as init process

Run /bin/init as init process

Run /bin/sh as init process

Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/admin-guide/init.rst for guidance.

CPU: 0 PID: 1 Comm: swapper Not tainted 5.10.55-yocto-standard #1

Hardware name: Generic AM33XX (Flattened Device Tree)

[<c010de44>] (unwind_backtrace) from [<c010a9ec>] (show_stack+0x18/0x1c)

[<c010a9ec>] (show_stack) from [<c0adb714>] (panic+0x108/0x31c)

[<c0adb714>] (panic) from [<c0ae86a0>] (kernel_init+0xf4/0x12c)

[<c0ae86a0>] (kernel_init) from [<c0100148>] (ret_from_fork+0x14/0x2c)

Exception stack(0xc1945fb0 to 0xc1945ff8)

5fa0: 00000000 00000000 00000000 00000000

5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000

5fe0: 00000000 00000000 00000000 00000000 00000013 00000000

—[ end Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/admin-guide/init.rst for guidance. ]—

I know there are some options that allow you to boot by executing commands while in uBoot durring boot (have tried that to no avail, saveenv returns card did not respond to voltage select. However I am trying to figure this out on a test device (which is why I have serial connection) so that I can implement this on devices I only have an ssh connection to (which is why I need a non-serial dependent solution). It has been weeks and I can feel myself slowly going nuts. Any help or pointers would be much appreciated. Thanks

bootserver=192.168.1.121, rootserver=192.168.1.121, rootpath=
VFS: Unable to mount root fs via NFS.

Check that your nfs path is actually exported and reachable on another linux device…

Regards,

You were correct about the nfs path not being reachable. I checked that the tftp component on my testing BBB, and then I tried mounting the nfs path on my testing BBB as well as another pc and I was able to mount successfully on both. However even though all components are working, and everything is reachable, I still get the same result and the same output. In the uEnv.txt, I only filled out what was necessary, do I need another line for rootpath=? I modified the folder permissions and ownership and then copied the rootfs into it. Do I need to change ownership to nobody and change the permission for all files and folders inside my nfs folder?