Hooking up the serial, I can see it partially boots, but somewhere in kernel init something fails:
BUFFALO U-BOOT Ver 1.07
AP83--539 (ar9100) U-boot 0.0.12
BUFFALO U-BOOT Ver 1.07
AP83--539 (ar9100) U-boot 0.0.12
64 MB
Memory Test (address line)
Memory Test start(0x00000000) end(0x04000000) size(67108864)
Data line test start:0x00000000 pattern 0x00000001 0x00000003 0x00000007 0x0000000F 0x00000005 0x00000015 0x00000055 0xAAAAAAAA
Address line test start:0x00000000 len:0x4000000 pattern 0xAAAAAAAA 0x55555555
Fill test patnum:5
fill Pattern 5555AAAA Writing... Reading...
fill Pattern AAAA5555 Writing... Reading...
fill Pattern 0000FFFF Writing... Reading...
fill Pattern FFFF0000 Writing... Reading...
fill Pattern AAAAAAAA Writing... Reading...
Top of RAM usable for U-Boot at: 84000000
Reserving 275k for U-Boot at: 83fb8000
Reserving 256k for malloc() at: 83f78000
Reserving 44 Bytes for Board Info at: 83f77fd4
Reserving 36 Bytes for Global Data at: 83f77fb0
Reserving 128k for boot params() at: 83f57fb0
Stack Pointer at: 83f57f98
Now running in RAM - U-Boot at: 83fb8000
Dev ID2:2222
Dev ID3:2201
Name: AMD-SPANSION Flash id: 0x1227E, Size: 33554432 bytes.
Flash: 32 MB
In: serial
Out: serial
Err: serial
Memory Test
uboot use 83F57FB0 - 84000000
Memory Test start(80000000) end(83F00000) size(03F00000)
Pattern 00000000 Writing... Reading...
Memory Test OK
### buf_ver=[1.07] U-Boot Ver.=[1.07]
### build_date(env)=[Dec 21 2009 - 10:37:11] build_date(bin)=[Dec 21 2009 - 10:37:11]
ag7100_enet_initialize...
: cfg1 0xf cfg2 0x7114
RTL8366 series driver, reading model-id...
ID:0x6027, REV:0x6
rtl8366sr_phy_setup ethUnit=0
Realtek 8366SR switch ID 0x8366
Realtek Greeen Ethernet Setup
eth0: 02:aa:bb:cc:dd:1a
eth0 up
: cfg1 0xf cfg2 0x7114
RTL8366 series driver, reading model-id...
eth1: 02:aa:bb:cc:dd:1a
eth1 up
eth0 02:AA:BB:CC:DD:1A
, eth1 02:AA:BB:CC:DD:1A
Trying eth0
eth0 is duplex
eth0 link down
FAIL
Trying eth1
eth1 link down
FAIL
tftp server(receive) go, waiting:4[sec]
Trying eth1
eth1 link down
FAIL
Trying eth0
eth0 is duplex
eth0 link down
FAIL
Load address: 0x81f00000
TftpServer Timeout;
Trying eth0
eth0 is duplex
eth0 link down
FAIL
Trying eth1
eth1 link down
FAIL
no file was loaded.
## Booting image at be060000 ...
Image Name: MIPS OpenWrt Linux-5.4.154
Created: 2021-10-24 9:01:35 UTC
Image Type: MIPS Linux Kernel Image (lzma compressed)
Data Size: 2047676 Bytes = 2 MB
Load Address: 80060000
Entry Point: 80060000
Verifying Checksum ... OK
Uncompressing Kernel Image ... OK
No initrd
## Transferring control to Linux (at address 80060000) ...
## Giving linux memsize in bytes, 67108864
Starting kernel ...
[ 0.000000] Linux version 5.4.154 (builder@buildhost) (gcc version 8.4.0 (OpenWrt GCC 8.4.0 r16325-88151b8303)) #0 Sun Oct 24 09:01:35 2021
[ 0.000000] printk: bootconsole [early0] enabled
[ 0.000000] CPU0 revision is: 00019374 (MIPS 24Kc)
[ 0.000000] MIPS: machine is Buffalo WZR-HP-G302H A1A0
[ 0.000000] SoC: Atheros AR9132 rev 2
[ 0.000000] Initrd not found or empty - disabling initrd
[ 0.000000] Primary instruction cache 64kB, VIPT, 4-way, linesize 32 bytes.
[ 0.000000] Primary data cache 32kB, 4-way, VIPT, cache aliases, linesize 32 bytes
[ 0.000000] Zone ranges:
[ 0.000000] Normal [mem 0x0000000000000000-0x0000000003ffffff]
[ 0.000000] Movable zone start for each node
[ 0.000000] Early memory node ranges
[ 0.000000] node 0: [mem 0x0000000000000000-0x0000000003ffffff]
[ 0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x0000000003ffffff]
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 16240
[ 0.000000] Kernel command line: console=ttyS0,115200 rootfstype=squashfs,jffs2
[ 0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear)
[ 0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear)
[ 0.000000] Writing ErrCtl register=00000000
[ 0.000000] Readback ErrCtl register=00000000
[ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[ 0.000000] Memory: 57272K/65536K available (5252K kernel code, 191K rwdata, 688K rodata, 1220K init, 205K bss, 8264K reserved, 0K cma-reserved)
[ 0.000000] SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 0.000000] NR_IRQS: 51
[ 0.000000] random: get_random_bytes called from 0x8065fa28 with crng_init=0
[ 0.000000] CPU clock: 400.000 MHz
[ 0.000000] clocksource: MIPS: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 9556302233 ns
[ 0.000011] sched_clock: 32 bits at 200MHz, resolution 5ns, wraps every 10737418237ns
[ 0.007914] Calibrating delay loop... 265.98 BogoMIPS (lpj=531968)
[ 0.050055] pid_max: default: 32768 minimum: 301
[ 0.054906] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 0.062217] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 0.076585] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[ 0.086362] futex hash table entries: 256 (order: -1, 3072 bytes, linear)
[ 0.093296] pinctrl core: initialized pinctrl subsystem
[ 0.101893] NET: Registered protocol family 16
[ 0.139117] workqueue: max_active 576 requested for napi_workq is out of range, clamping between 1 and 512
[ 0.153707] clocksource: Switched to clocksource MIPS
[ 0.160132] thermal_sys: Registered thermal governor 'step_wise'
[ 0.160598] NET: Registered protocol family 2
[ 0.171244] IP idents hash table entries: 2048 (order: 2, 16384 bytes, linear)
[ 0.179537] tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 4096 bytes, linear)
[ 0.187967] TCP established hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 0.195637] TCP bind hash table entries: 1024 (order: 0, 4096 bytes, linear)
[ 0.202700] TCP: Hash tables configured (established 1024 bind 1024)
[ 0.209248] UDP hash table entries: 256 (order: 0, 4096 bytes, linear)
[ 0.215829] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes, linear)
[ 0.223175] NET: Registered protocol family 1
[ 0.227599] PCI: CLS 0 bytes, default 32
[ 0.236758] workingset: timestamp_bits=14 max_order=14 bucket_order=0
[ 0.253972] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[ 0.259821] jffs2: version 2.2 (NAND) (SUMMARY) (LZMA) (RTIME) (CMODE_PRIORITY) (c) 2001-2006 Red Hat, Inc.
[ 0.287643] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)
[ 0.298474] pinctrl-single 18040028.pinmux: 64 pins, size 8
[ 0.304799] gpio-export gpio-export: 1 gpio(s) exported
[ 0.311033] Serial: 8250/16550 driver, 16 ports, IRQ sharing enabled
[ 0.320827] printk: console [ttyS0] disabled
[ 0.325224] 18020000.uart: ttyS0 at MMIO 0x18020000 (irq = 9, base_baud = 12500000) is a 16550A
[ 0.333937] printk: console [ttyS0] enabled
[ 0.333937] printk: console [ttyS0] enabled
[ 0.342356] printk: bootconsole [early0] disabled
[ 0.342356] printk: bootconsole [early0] disabled
[ 0.365639] spi-nor spi0.0: unrecognized JEDEC id bytes: ff ff ff ff ff ff
[ 0.372682] spi-nor: probe of spi0.0 failed with error -2
[ 0.379509] spi-nor spi0.1: unrecognized JEDEC id bytes: ff ff ff ff ff ff
[ 0.386530] spi-nor: probe of spi0.1 failed with error -2
[ 0.394660] libphy: Fixed MDIO Bus: probed
[ 0.403476] ag71xx 19000000.eth: invalid MAC address, using random address
[ 1.042168] libphy: ag71xx_mdio: probed
[ 1.047356] ag71xx 19000000.eth: connected to PHY at mdio.0:00 [uid=0000ffff, driver=Generic PHY]
[ 1.057261] eth0: Atheros AG71xx at 0xb9000000, irq 4, mode: rgmii
[ 1.064011] i2c /dev entries driver
[ 1.070482] NET: Registered protocol family 10
[ 1.082207] Segment Routing with IPv6
[ 1.086129] NET: Registered protocol family 17
[ 1.090705] bridge: filtering via arp/ip/ip6tables is no longer available by default. Update your scripts to load br_netfilter if you need this.
[ 1.103751] 8021q: 802.1Q VLAN Support v1.8
[ 1.109226] PCI host bridge /ahb/apb/pcie-controller@180c0000 ranges:
[ 1.115822] MEM 0x0000000010000000..0x0000000013ffffff
[ 1.121100] IO 0x0000000000000000..0x0000000000000000
Not sure how I can use that to make booting work on this unit, so I guess I'm back to 19.07.x.
Final update:
After trying to recover via TFTP, I tried the following files:
- https://downloads.openwrt.org/releases/21.02.0/targets/ath79/generic/openwrt-21.02.0-ath79-generic-buffalo_wzr-hp-g300nh-rb-squashfs-tftp.bin
- https://downloads.openwrt.org/releases/21.02.0/targets/ath79/generic/openwrt-21.02.0-ath79-generic-buffalo_wzr-hp-g300nh-s-squashfs-tftp.bin
The first one flashed fine and kinda booted, but constantly stopped and ran into failsafe mode, because it incorrectly detected some failsafe-button having been pressed (not up on network, serial console required).
Using the second image (openwrt-21.02.0-ath79-generic-buffalo_wzr-hp-g300nh-s-squashfs-tftp.bin) I was able to boot my WZR-HP-G300NH B0B0 device back into normal operation with a clean state without any serial-intervention.
So for other B0B0 owners out there, the upgrade path to 21.02.x is the wzr-hp-g300nh-s series of images 