port-evbarm/60066: No root filesystem found on Raspberry Pi Compute Module 3

["Pierre Pronchery via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60066
>Category:       port-evbarm
>Synopsis:       The flash device is not found when booting from RPi CM3
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-evbarm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Mar 09 05:35:00 +0000 2026
>Originator:     Pierre Pronchery <khorben%defora.org@localhost>
>Release:        NetBSD 11.99.5
>Organization:
NetBSD
>Environment:
NetBSD 11.99.5 (GENERIC64) #2: Fri Mar  6 04:08:59 CET 2026
Architecture: evbarm
Machine: aarch64
>Description:
When booting a Raspberry Pi 3 Compute Module on its official I/O debug
board, the NetBSD kernel does not detect the flash filesystem.

This occured with the latest available -current at the time of this
test, after formatting the flash device, placing the kernel and base
system, setting the debug board's jumper J4 as "boot enable", connecting
the serial console (GPIO 13 & 14), and powering up the board.

The kernel was built as instructed, with extra options SHDC_DEBUG and
SDMMC_DEBUG.

The full dmesg captured on the serial console:

NetBSD/evbarm (fdt) booting ...
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
    2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013,
    2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023,
    2024, 2025, 2026
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 11.99.5 (GENERIC64) #2: Fri Mar  6 04:08:59 CET 2026
 khorben@reapr.station.defora:/home/khorben/Projects/EdgeBSD/src-current/obj-evbarm-aarch64/sys/arch/evbarm/compile/GENERIC64
total memory = 928 MB
avail memory = 893 MB
armfdt0 (root)
simplebus0 at armfdt0: Raspberry Pi Compute Module 3 Rev 1.0
simplebus1 at simplebus0
simplebus2 at simplebus0
cpus0 at simplebus0
simplebus3 at simplebus0
cpu0 at cpus0: Arm Cortex-A53 r0p4 (v8-A), id 0x0
cpu0: package 0, core 0, smt 0, numa 0
cpu1 at cpus0: Arm Cortex-A53 r0p4 (v8-A), id 0x1
cpu1: package 0, core 1, smt 0, numa 0
cpu2 at cpus0: Arm Cortex-A53 r0p4 (v8-A), id 0x2
cpu2: package 0, core 2, smt 0, numa 0
cpu3 at cpus0: Arm Cortex-A53 r0p4 (v8-A), id 0x3
cpu3: package 0, core 3, smt 0, numa 0
bcmicu0 at simplebus1
fclock0 at simplebus2: 19200000 Hz fixed clock (osc)
bcmcprman0 at simplebus1: BCM283x Clock Controller
bcmaux0 at simplebus1
fclock1 at simplebus2: 480000000 Hz fixed clock (otg)
bcmicu1 at simplebus1: Multiprocessor
syscon0 at simplebus1: couldn't get registers
gtmr0 at simplebus0: Generic Timer
gtmr0: interrupting on local_intc irq 3
armgtmr0 at gtmr0: Generic Timer (19200 kHz, virtual)
bcmgpio0 at simplebus1: GPIO controller 2835
bcmgpio0: pins 0..31 interrupting on icu irq 49
bcmgpio0: pins 32..54 interrupting on icu irq 50
gpio0 at bcmgpio0: 54 pins
fregulator0 at simplebus0: 1V8
plcom0 at simplebus1: ARM PL011 UART
plcom0: txfifo 16 bytes
plcom0: console
plcom0: interrupting on icu irq 57
/soc/thermal@7e212000 at simplebus1 not configured
bcmdmac0 at simplebus1: DMA0 DMA2 DMA4 DMA5 DMA6 DMA7 DMA8 DMA9 DMA10 DMA11
/soc/power at simplebus1 not configured
/phy at simplebus0 not configured
bsciic0 at simplebus1: Broadcom Serial Controller
bsciic0: interrupting on icu irq 53
iic0 at bsciic0: I2C bus
bcmmbox0 at simplebus1: VC mailbox
bcmmbox0: interrupting on icu irq 65
vcmbox0 at bcmmbox0
/soc/timer@7e003000 at simplebus1 not configured
/soc/txp@7e004000 at simplebus1 not configured
bcmsdhost0 at simplebus1: SD HOST controller
bcmsdhost0: interrupting on icu irq 56
bsciic1 at simplebus1: Broadcom Serial Controller
bsciic1: interrupting on icu irq 53
iic1 at bsciic1: I2C bus
bsciic2 at simplebus1: Broadcom Serial Controller
bsciic2: interrupting on icu irq 53
iic2 at bsciic2: I2C bus
dwctwo0 at simplebus1: USB controller
dwctwo0: interrupting on icu irq 9
bcmpmwdog0 at simplebus1: Power management, Reset and Watchdog controller
/soc/vec@7e806000 at simplebus1 not configured
/soc/hdmi@7e902000 at simplebus1 not configured
/soc/gpu at simplebus1 not configured
genfb0 at simplebus1no data for est. mode 640x480x67
: switching to framebuffer console
wsdisplay0 at genfb0 kbdmux 1: console (default, vt100 emulation)
vchiq0 at simplebus1: BCM2835 VCHIQ
armpmu0 at simplebus0: Performance Monitor Unit
gpioleds0 at simplebus0:
bcmrng0 at simplebus1: RNG
entropy: ready
sdmmc0 at bcmsdhost0
usb0 at dwctwo0: USB revision 2.0
armpmu0: interrupting on local_intc irq 9
uhub0 at usb0: NetBSD (0x0000) DWC2 root hub (0x0000), class 9/0, rev 2.00/1.00, addr 1
sdmmc0: direct I/O error 5, r=6 p=0xffffc000b1801e3c write
sdmmc_io_send_op_cond: ocr = 0
sdmmc_io_send_op_cond: error = 5
sdmmc0: sdmmc_mem_send_op_cond: ocr=0
sdmmc0: sdmmc_mem_send_op_cond: error=5, ocr=0
sdmmc0: switch to MMC mode
sdmmc0: sdmmc_mem_send_op_cond: ocr=0
sdmmc0: sdmmc_mem_send_op_cond: error=5, ocr=0
sdmmc0: couldn't read memory OCR
sdmmc0: couldn't enable card: 5
swwdog0: software watchdog initialized
WARNING: 2 errors while detecting hardware; check system log.
boot device: <unknown>
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
unknown device major 0xffffffffffffffff
root device:
>How-To-Repeat:
After setting the jumper J4 to "USB slave", use rpiboot from GitHub's
raspberrypi/usbboot repository to expose the flash storage over USB, as
a block device:

```
$ ./rpiboot
RPIBOOT: build-date 2026/02/28 pkg-version local 101f2d00

Please fit the EMMC_DISABLE / nRPIBOOT jumper before connecting the
power and USB cables to the target device.
If the device fails to connect then please see https://rpltd.co/rpiboot
for debugging tips.

Waiting for BCM2835/6/7/2711/2712...

Loading embedded: bootcode.bin
Sending bootcode.bin
Successful read 4 bytes 
Waiting for BCM2835/6/7/2711/2712...

Loading embedded: bootcode.bin
Loading embedded: bootcode.bin
Second stage boot server
Cannot open file autoboot.txt
Cannot open file config.txt
Cannot open file recovery.elf
Loading embedded: start.elf
File read: start.elf
Cannot open file fixup.dat
Second stage boot server done
```

Make a cup of tea, set the jumper J4 to "boot enable", sit down, power
the board, and take notes.
>Fix:
Unknown as of now, but very welcome.