Troubleshooting RPi 3B di rumah yang gak mau nyala

Salah satu alasan saya pulang ke rumah adalah untuk memperbaiki dan mengatur ulang raspi yang biasa saya jalankan dari wifi rumah. Awalnya, saya kira ada misconfig di watchdog yang membuat raspi saya restart terus, tapi nampaknya tidak. Karena ketika saya reboot, saya sempat bisa ping dari local network. Sayangnya, ini tidak bertahan lama. Sekitar 8 jam setelah saya berhasil ping, raspi saya down. Saya reboot berkali-kali juga tidak nyambung-nyambung ke wifi.

Akhirnya, saya coba untuk melihat outputnya via UART menggunakan GPIO [port 14 dan 15](https://pinout.xyz/pinout/). BTW, saya tidak punya monitor eksternal untuk melihat output display/console via HDMI. Ketika saya coba sambung, ternyata tidak keluar apa-apa :) saya sudah cukup yakin kabel dan USB serial converter saya berfungsi. Sudah saya tes dengan short Rx dan Tx. Baud rate juga sudah sama dengan yang diatur di cmdline.txt. Setelah mengganti `console=serial0,115200` menjadi `console=ttyACM0,115200`, saya mulai mendapat output walau kadang juga tidak dapat atau malah garbled characters. Saya bahkan sempat coba ganti converter serial, awalnya pakai yang CH340 lalu saya ganti jadi yang CP210x (saya lupa persisnya, ini sudah saya beli dari lama, dan tidak ada marking di chipnya). Yang aneh adalah kadang outputnya muncul kadang tidak. Bahkan, kadang USB flash drive yang saya pakai untuk boot juga lampunya tidak berkedip. Kecurigaan saya: (1) power adapter issue, yang saya gunakan mungkin tidak bisa suplai 3A karena saya memang lihat ratingnya 1A hehe, (2) mungkin converter serial saya memakai 5V bukan 3.3V, lalu merusak sesuatu, (3) ada yang corrupt di filesystemnya.

Hal terakhir yang saya coba lakukan adalah membackup isi USB flash drive boot saya dan saya ganti dengan SD image Raspberry Pi OS yang baru. Hasilnya, sama saja. Saya sudah coba sambungkan ethernet juga tidak bisa di-ping. Di console juga tidak dapat shell, tapi ketika saya colokkan USB drive lain, kelihatannya terdeteksi atau tidak nge-hang (mungkinkah ini ada kaitannya dengan error USB di bawah?):

Saya pikir ini mungkin karena saya belum enable console via serial menggunakan getty. Ini belum saya coba. Tapi yang sudah saya coba adalah enable debug shell pada cmdline.txt menggunakan flag `systemd.debug-shell=1`. Namun, tidak berhasil dapat shell juga. Behavior kadang boot kadang tidak juga masih saya dapatkan.

Ide-ide untuk troubleshooting berikutnya:

1. Ganti power adapter dengan yang rated 3A
2. Coba boot dari SD Card, bukan USB boot
3. Coba lihat output via HDMI
4. Enable getty untuk serial console
5. Coba sambungkan Ethernet ke router, bukan ke laptop, mungkin yang issue di kabel UTP-nya tidak cross

Salah satu hal unik yang saya pelajari hari ini: di Raspberry Pi 3B, ada dua serial port, satu yang UART (PL001) dan satu lagi Mini UART. By default, yang primary /console ada di Mini UART karena yang UART0 atau PL001 dipakai oleh Bluetooth (lebih ngebut dan kaya feature). Jadi, supaya bisa akses console via UART0, perlu disable bluetooth atau pindahkan dulu bluetooth ke miniuart via pengaturan DT overlay di config.txt. Referensi:  

## Lampiran log

```
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
[    0.000000] Linux version 6.12.47+rpt-rpi-v8 (serge@raspberrypi.com) (aarch64-linux-gnu-gcc-14 (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils )
[    0.000000] KASLR enabled
[    0.000000] random: crng init done
[    0.000000] Machine model: Raspberry Pi 3 Model B Rev 1.2
[    0.000000] earlycon: pl11 at MMIO32 0x000000003f201000 (options '')
[    0.000000] printk: legacy bootconsole [pl11] enabled
[    0.000000] efi: UEFI not found.
[    0.000000] Reserved memory: created CMA memory pool at 0x000000001e000000, size 256 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
[    0.000000] OF: reserved mem: 0x000000001e000000..0x000000002dffffff (262144 KiB) map reusable linux,cma
[    0.000000] NUMA: Faking a node at [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] NODE_DATA(0) allocated [mem 0x3b1fd000-0x3b1ffcff]
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000]   DMA32    empty
[    0.000000]   Normal   empty
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] On node 0, zone DMA: 19456 pages in unavailable ranges
[    0.000000] percpu: Embedded 33 pages/cpu s95256 r8192 d31720 u135168
[    0.000000] Detected VIPT I-cache on CPU0
[    0.000000] CPU features: kernel page table isolation forced ON by KASLR
[    0.000000] CPU features: detected: Kernel page table isolation (KPTI)
[    0.000000] CPU features: detected: ARM erratum 843419
[    0.000000] CPU features: detected: ARM erratum 845719
[    0.000000] alternatives: applying boot alternatives
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 cgroup_disable=memory snd_bcm2835.enable_headt
[    0.000000] cgroup: Disabling memory control group subsystem
[    0.000000] Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes, linear)
[    0.000000] Inode-cache hash table entries: 65536 (order: 7, 524288 bytes, linear)
[    0.000000] Fallback order for Node 0: 0
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 242688
[    0.000000] Policy zone: DMA
[    0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[    0.000000] ftrace: allocating 45279 entries in 177 pages
[    0.000000] ftrace: allocated 177 pages with 4 groups
[    0.000000] rcu: Preemptible hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000]  Trampoline variant of Tasks RCU enabled.
[    0.000000]  Rude variant of Tasks RCU enabled.
[    0.000000]  Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[    0.000000] RCU Tasks: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] RCU Tasks Rude: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] Root IRQ handler: bcm2836_arm_irqchip_handle_irq
[    0.000000] rcu: srcu_init: Setting srcu_struct sizes based on contention.
[    0.000000] arch_timer: cp15 timer(s) running at 19.20MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x46d987e47, max_idle_ns: 440795202767 ns
[    0.000000] sched_clock: 56 bits at 19MHz, resolution 52ns, wraps every 4398046511078ns
[    0.008309] Console: colour dummy device 80x25
[    0.012787] printk: legacy console [tty1] enabled
[    0.017528] printk: legacy bootconsole [pl11] disabled
[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]
[    0.000000] Linux version 6.12.47+rpt-rpi-v8 (serge@raspberrypi.com) (aarch64-linux-gnu-gcc-14 (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils )
[    0.000000] KASLR enabled
[    0.000000] random: crng init done
[    0.000000] Machine model: Raspberry Pi 3 Model B Rev 1.2
[    0.000000] earlycon: pl11 at MMIO32 0x000000003f201000 (options '')
[    0.000000] printk: legacy bootconsole [pl11] enabled
[    0.000000] efi: UEFI not found.
[    0.000000] Reserved memory: created CMA memory pool at 0x000000001e000000, size 256 MiB
[    0.000000] OF: reserved mem: initialized node linux,cma, compatible id shared-dma-pool
[    0.000000] OF: reserved mem: 0x000000001e000000..0x000000002dffffff (262144 KiB) map reusable linux,cma
[    0.000000] NUMA: Faking a node at [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] NODE_DATA(0) allocated [mem 0x3b1fd000-0x3b1ffcff]
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000]   DMA32    empty
[    0.000000]   Normal   empty
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x000000003b3fffff]
[    0.000000] On node 0, zone DMA: 19456 pages in unavailable ranges
[    0.000000] percpu: Embedded 33 pages/cpu s95256 r8192 d31720 u135168
[    0.000000] Detected VIPT I-cache on CPU0
[    0.000000] CPU features: kernel page table isolation forced ON by KASLR
[    0.000000] CPU features: detected: Kernel page table isolation (KPTI)
[    0.000000] CPU features: detected: ARM erratum 843419
[    0.000000] CPU features: detected: ARM erratum 845719
[    0.000000] alternatives: applying boot alternatives
[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=1 snd_bcm2835.enable_headphones=0 cgroup_disable=memory snd_bcm2835.enable_headt
[    0.000000] cgroup: Disabling memory control group subsystem
[    0.000000] Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes, linear)
[    0.000000] Inode-cache hash table entries: 65536 (order: 7, 524288 bytes, linear)
[    0.000000] Fallback order for Node 0: 0
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 242688
[    0.000000] Policy zone: DMA
[    0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[    0.000000] ftrace: allocating 45279 entries in 177 pages
[    0.000000] ftrace: allocated 177 pages with 4 groups
[    0.000000] rcu: Preemptible hierarchical RCU implementation.
[    0.000000] rcu:     RCU event tracing is enabled.
[    0.000000]  Trampoline variant of Tasks RCU enabled.
[    0.000000]  Rude variant of Tasks RCU enabled.
[    0.000000]  Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[    0.000000] RCU Tasks: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] RCU Tasks Rude: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 rcu_task_cpu_ids=4.
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] Root IRQ handler: bcm2836_arm_irqchip_handle_irq
[    0.000000] rcu: srcu_init: Setting srcu_struct sizes based on contention.
[    0.000000] arch_timer: cp15 timer(s) running at 19.20MHz (phys).
[    0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x46d987e47, max_idle_ns: 440795202767 ns
[    0.000000] sched_clock: 56 bits at 19MHz, resolution 52ns, wraps every 4398046511078ns
[    0.008309] Console: colour dummy device 80x25
[    0.012787] printk: legacy console [tty1] enabled
[    0.017528] printk: legacy bootconsole [pl11] disabled
[    0.022774] Calibrating delay loop (skipped), value calculated using timer frequency.. 38.40 BogoMIPS (lpj=76800)
[    0.022800] pid_max: default: 32768 minimum: 301
[    0.022861] LSM: initializing lsm=capability
[    0.023025] Mount-cache hash table entries: 2048 (order: 2, 16384 bytes, linear)
[    0.023053] Mountpoint-cache hash table entries: 2048 (order: 2, 16384 bytes, linear)
[    0.025192] rcu: Hierarchical SRCU implementation.
[    0.025223] rcu:     Max phase no-delay instances is 1000.
[    0.025450] Timer migration: 1 hierarchy levels; 8 children per group; 1 crossnode level
[    0.026442] EFI services will not be available.
[    0.026675] smp: Bringing up secondary CPUs ...
[    0.027309] Detected VIPT I-cache on CPU1
[    0.027412] CPU1: Booted secondary processor 0x0000000001 [0x410fd034]
[    0.028118] Detected VIPT I-cache on CPU2
[    0.028188] CPU2: Booted secondary processor 0x0000000002 [0x410fd034]
[    0.028810] Detected VIPT I-cache on CPU3
[    0.028879] CPU3: Booted secondary processor 0x0000000003 [0x410fd034]
[    0.029073] smp: Brought up 1 node, 4 CPUs
[    0.029137] SMP: Total of 4 processors activated.
[    0.029148] CPU: All CPU(s) started at EL2
[    0.029172] CPU features: detected: 32-bit EL0 Support
[    0.029184] CPU features: detected: 32-bit EL1 Support
[    0.029197] CPU features: detected: CRC32 instructions
[    0.029252] alternatives: applying system-wide alternatives
[    0.030647] Memory: 643000K/970752K available (14336K kernel code, 2406K rwdata, 4824K rodata, 2048K init, 577K bss, 60648K reserved, 262144K c)
[    0.031284] devtmpfs: initialized
[    0.038575] Enabled cp15_barrier support
[    0.038617] Enabled setend support
[    0.038826] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
[    0.038858] futex hash table entries: 1024 (order: 4, 65536 bytes, linear)
[    0.047637] 2G module region forced by RANDOMIZE_MODULE_REGION_FULL
[    0.047685] 0 pages in range for non-PLT usage
[    0.047690] 518176 pages in range for PLT usage
[    0.047917] pinctrl core: initialized pinctrl subsystem
[    0.048448] DMI not present or invalid.
[    0.050771] NET: Registered PF_NETLINK/PF_ROUTE protocol family
[    0.054608] DMA: preallocated 1024 KiB GFP_KERNEL pool for atomic allocations
[    0.055142] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for atomic allocations
[    0.055754] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations
[    0.055823] audit: initializing netlink subsys (disabled)
[    0.056064] audit: type=2000 audit(0.048:1): state=initialized audit_enabled=0 res=1
[    0.056553] thermal_sys: Registered thermal governor 'step_wise'
[    0.056600] cpuidle: using governor menu
[    0.056813] hw-breakpoint: found 6 breakpoint and 4 watchpoint registers.
[    0.056921] ASID allocator initialised with 32768 entries
[    0.057543] Serial: AMBA PL011 UART driver
[    0.061248] bcm2835-mbox 3f00b880.mailbox: mailbox enabled
[    0.070998] raspberrypi-firmware soc:firmware: Attached to firmware from 2025-08-20T17:04:09, variant start
[    0.075008] raspberrypi-firmware soc:firmware: Firmware hash is cd866525580337c0aee4b25880e1f5f9f674fb24
[    0.082966] bcm2835-dma 3f007000.dma-controller: DMA legacy API manager, dmachans=0x1
[    0.083881] iommu: Default domain type: Translated
[    0.083901] iommu: DMA domain TLB invalidation policy: strict mode
[    0.084662] SCSI subsystem initialized
[    0.084872] usbcore: registered new interface driver usbfs
[    0.084916] usbcore: registered new interface driver hub
[    0.084964] usbcore: registered new device driver usb
[    0.085276] pps_core: LinuxPPS API ver. 1 registered
[    0.085291] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti 
[    0.085318] PTP clock support registered
[    0.086898] vgaarb: loaded
[    0.087354] clocksource: Switched to clocksource arch_sys_counter
[    0.960423] VFS: Disk quotas dquot_6.6.0
[    0.960482] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
[    0.967193] NET: Registered PF_INET protocol family
[    0.967433] IP idents hash table entries: 16384 (order: 5, 131072 bytes, linear)
[    0.968656] tcp_listen_portaddr_hash hash table entries: 512 (order: 1, 8192 bytes, linear)
[    0.968695] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear)
[    0.968719] TCP established hash table entries: 8192 (order: 4, 65536 bytes, linear)
[    0.968796] TCP bind hash table entries: 8192 (order: 6, 262144 bytes, linear)
[    0.969034] TCP: Hash tables configured (established 8192 bind 8192)
[    0.969273] MPTCP token hash table entries: 1024 (order: 2, 24576 bytes, linear)
[    0.969335] UDP hash table entries: 512 (order: 2, 16384 bytes, linear)
[    0.969374] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes, linear)
[    0.969510] NET: Registered PF_UNIX/PF_LOCAL protocol family
[    0.969974] RPC: Registered named UNIX socket transport module.
[    0.969993] RPC: Registered udp transport module.
[    0.970005] RPC: Registered tcp transport module.
[    0.970016] RPC: Registered tcp-with-tls transport module.
[    0.970028] RPC: Registered tcp NFSv4.1 backchannel transport module.
[    0.970050] PCI: CLS 0 bytes, default 64
[    0.970532] Trying to unpack rootfs image as initramfs...
[    0.975856] kvm [1]: nv: 554 coarse grained trap handlers
[    0.976384] kvm [1]: IPA Size Limit: 40 bits
[    0.977552] kvm [1]: Hyp nVHE mode initialized successfully
[    0.980318] Initialise system trusted keyrings
[    0.980711] workingset: timestamp_bits=42 max_order=18 bucket_order=0
[    0.981518] NFS: Registering the id_resolver key type
[    0.981574] Key type id_resolver registered
[    0.981587] Key type id_legacy registered
[    0.981614] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    0.981631] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[    0.982221] Key type asymmetric registered
[    0.982250] Asymmetric key parser 'x509' registered
[    0.982314] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 247)
[    0.982561] io scheduler mq-deadline registered
[    0.982578] io scheduler kyber registered
[    0.982616] io scheduler bfq registered
[    0.984534] pinctrl-bcm2835 3f200000.gpio: GPIO_OUT persistence: yes
[    1.467652] Freeing initrd memory: 15632K
[    1.471334] ledtrig-cpu: registered to indicate activity on CPUs
[    1.473865] simple-framebuffer 3eaa9000.framebuffer: framebuffer at 0x3eaa9000, 0x151800 bytes
[    1.473946] simple-framebuffer 3eaa9000.framebuffer: format=a8r8g8b8, mode=720x480x32, linelength=2880
[    1.476756] Console: switching to colour frame buffer device 90x30
[    1.479761] simple-framebuffer 3eaa9000.framebuffer: fb0: simplefb registered!
[    1.483492] Serial: 8250/16550 driver, 1 ports, IRQ sharing enabled
[    1.486009] bcm2835-rng 3f104000.rng: hwrng registered
[    1.487207] vc-mem: phys_addr:0x00000000 mem_base=0x3ec00000 mem_size:0x40000000(1024 MiB)
[    1.497366] brd: module loaded
[    1.502878] loop: module loaded
[    1.504466] Loading iSCSI transport class v2.0-870.
[    1.508510] usbcore: registered new interface driver lan78xx
[    1.509533] usbcore: registered new interface driver smsc95xx
[    1.510637] dwc_otg: version 3.00a 10-AUG-2012 (platform bus)
[    2.239382] Core Release: 2.80a
[    2.240319] Setting default values for core params
[    2.241222] Finished setting default values for core params
[    2.442321] Using Buffer DMA mode
[    2.443233] Periodic Transfer Interrupt Enhancement - disabled
[    2.444190] Multiprocessor Interrupt Enhancement - disabled
[    2.445130] OTG VER PARAM: 0, OTG VER FLAG: 0
[    2.446061] Dedicated Tx FIFOs mode
[    2.450091] INFO:: FIQ DMA bounce buffers: virt = ffffffc080ceb000 dma = 0x00000000de400000 len=9024
[    2.452016] FIQ FSM acceleration enabled for :
[    2.452016] Non-periodic Split Transactions
[    2.452016] Periodic Split Transactions
[    2.452016] High-Speed Isochronous Endpoints
[    2.452016] Interrupt/Control Split Transaction hack enabled
[    2.456324] INFO:: MPHI regs_base at ffffffc080075000
[    2.457216] dwc_otg 3f980000.usb: DWC OTG Controller
[    2.458046] dwc_otg 3f980000.usb: new USB bus registered, assigned bus number 1
[    2.458871] dwc_otg 3f980000.usb: irq 74, io mem 0x00000000
[    2.459714] Init: Port Power? op_state=1
[    2.460515] Init: Power Port (0)
[    2.461449] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 6.12
[    2.463097] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[    2.463999] usb usb1: Product: DWC OTG Controller
[    2.464873] usb usb1: Manufacturer: Linux 6.12.47+rpt-rpi-v8 dwc_otg_hcd
[    2.465762] usb usb1: SerialNumber: 3f980000.usb
[    2.467147] hub 1-0:1.0: USB hub found
[    2.468054] hub 1-0:1.0: 1 port detected
[    2.470174] usbcore: registered new interface driver uas
[    2.471093] usbcore: registered new interface driver usb-storage
[    2.472292] mousedev: PS/2 mouse device common for all mice
[    2.474842] sdhci: Secure Digital Host Controller Interface driver
[    2.475807] sdhci: Copyright(c) Pierre Ossman
[    2.476755] sdhci-pltfm: SDHCI platform and OF driver helper
[    2.477789] hid: raw HID events driver (C) Jiri Kosina
[    2.478729] usbcore: registered new interface driver usbhid
[    2.479581] usbhid: USB HID core driver
[    2.484039] hw perfevents: enabled with armv8_cortex_a53 PMU driver, 7 (0,8000003f) counters available
[    2.486614] NET: Registered PF_PACKET protocol family
[    2.487636] Key type dns_resolver registered
[    2.507569] registered taskstats version 1
[    2.508657] Loading compiled-in X.509 certificates
[    2.517040] Demotion targets for Node 0: null
[    2.518683] Key type .fscrypt registered
[    2.520372] Key type fscrypt-provisioning registered
[    2.528892] bcm2835-wdt bcm2835-wdt: Broadcom BCM2835 watchdog timer
[    2.530335] bcm2835-power bcm2835-power: Broadcom BCM2835 power domains driver
[    2.532180] mmc-bcm2835 3f300000.mmcnr: mmc_debug:0 mmc_debug2:0
[    2.533040] mmc-bcm2835 3f300000.mmcnr: DMA channel allocated
[    2.560937] uart-pl011 3f201000.serial: there is not valid maps for state default
[    2.561957] uart-pl011 3f201000.serial: cts_event_workaround enabled
[    2.563218] 3f201000.serial: ttyAMA0 at MMIO 0x3f201000 (irq = 99, base_baud = 0) is a PL011 rev2
[    2.565165] printk: legacy console [ttyAMA0] enabled
[    3.877827] Indeed it is in host mode hprt0 = 00021501
[    3.883971] of_cfs_init
[    3.887416] of_cfs_init: OK
[    3.891297] clk: Disabling unused clocks
[    3.896332] PM: genpd: Disabling unused power domains
[    3.905087] sdhost-bcm2835 3f202000.mmc: loaded - DMA enabled (>1)
[    3.916764] Freeing unused kernel memory: 2048K
[    3.922326] Run /init as init process
[    4.016426] mmc1: new high speed SDIO card at address 0001
[    4.075413] usb 1-1: new high-speed USB device number 2 using dwc_otg
[    4.082931] Indeed it is in host mode hprt0 = 00001101
[    4.283719] usb 1-1: New USB device found, idVendor=0424, idProduct=9514, bcdDevice= 2.00
[    4.293784] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[    4.302680] hub 1-1:1.0: USB hub found
[    4.307653] hub 1-1:1.0: 5 ports detected
[    4.599448] usb 1-1.1: new high-speed USB device number 3 using dwc_otg
[    4.695569] usb 1-1.1: New USB device found, idVendor=0424, idProduct=ec00, bcdDevice= 2.00
[    4.705790] usb 1-1.1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[    4.716783] smsc95xx v2.0.0
[    4.809435] SMSC LAN8700 usb-001:003:01: attached PHY driver (mii_bus:phy_addr=usb-001:003:01, irq=184)
[    4.821560] smsc95xx 1-1.1:1.0 eth0: register 'smsc95xx' at usb-3f980000.usb-1.1, smsc95xx USB 2.0 Ethernet, b8:27:eb:4a:24:b1
[    4.907377] usb 1-1.4: new full-speed USB device number 4 using dwc_otg
[    4.987368] usb 1-1.4: device descriptor read/64, error -32
[    5.167365] usb 1-1.4: device descriptor read/64, error -32
[    5.347365] usb 1-1.4: new full-speed USB device number 5 using dwc_otg
[    5.427366] usb 1-1.4: device descriptor read/64, error -32
[    5.607366] usb 1-1.4: device descriptor read/64, error -32
[    5.719543] usb 1-1-port4: attempt power cycle
[    6.307372] usb 1-1.4: new full-speed USB device number 6 using dwc_otg
[    6.719363] usb 1-1.4: device not accepting address 6, error -32
[    6.811442] usb 1-1.4: new full-speed USB device number 7 using dwc_otg
[    7.227368] usb 1-1.4: device not accepting address 7, error -32
[    7.234529] usb 1-1-port4: unable to enumerate USB device
```