Black Panther X2 flashes OpenWrt: TF card can run, but eMMC is "lost"? A brick saving note takes you to revive in place in 10 minutes

1. Phenomenon review

follow the tutorial on the Internet, write openwrt-rk3566-panther-x2-ext4.img to the TF card with Win32DiskImager, power on → the network port light is on→ the computer gets 192.168.1.1 → everything is fine.
wanted to permanently move the system into 32 GB eMMC, so I dd if=xxx.img of=/dev/mmcblk0 bs=1M, and restarted the card without power.
the router indicator flashes wildly for 30 seconds and then stays on, but the computer has not been able to get the IP for a long time, the arp table is empty, and the ttl serial port is only stopped in one line
Waiting for root device PARTUUID=xxxx-xxxx...
After another 10 seconds, the kernel goes directly into initramfs. The network protocol stack did not rise at all - the "eMMC brick" was reached.

2. Why does TF card work, but eMMC does not?

a word: Image writing misalignment + root partition cannot be found → kernel stops initramfs → network protocol stack does not come up→ The computer "cannot find the IP".

3. 30 seconds to determine where the stuck is

TTL Serial port 115200 power-on
- see Hit any key to stop autoboot and keep pressing the space → to enter U-Boot.
- if prompted Card did not respond to voltage select! → the first 4 MiB was flushed, the bootloader is hung.
- if you keep Waiting for root device PARTUUID=... → but the root partition path is wrong, it is easy to fix.
computer network port capture packet capture
only DHCP Discover, no Offer→ network port is not initialized, confirming that "it is not hung to the root".

4. Three-step method of non-destructive brick rescue

(All the following operations are done in "OpenWrt started by TF card", do not write eMMC directly with a PC )

(1) Confirm the eMMC device name

lsblk

output example

mmcblk0 29.1G / ← eMMC mmcblk1 14.9G / ← TF Card

remember whether it's mmcblk0 or mmcblk2, DTS serial numbers can vary from batch to batch.

(2) with 4 MiB offset write mirror

official bootloader 4 MiB, the command must be seek=4:

dd if=/tmp/openwrt-rk3566-panther-x2-ext4.img of=/dev/mmcblk0 bs=1M seek=4 conv=fsync sync poweroff

not writing seek=4 will flush out boot0, really · Brick .

(3) Let the kernel find the root partition

Temporary Law (TTL On-site Change)
Power-on press the space to enter U-Boot:

setenv bootargs 'console=ttyS2,115200n8 root=/dev/mmcblk0p2 rootwait' saveenv reset

permanent method (TF card system modification)
```
mount /dev/mmcblk0p1 /mnt vi /mnt/boot/boot.txt # Change root=PARTUUID=xxxx to root=/dev/mmcblk0p2 mkimage -T script -A arm64 -C none -d /mnt/boot/boot.txt /mnt/boot/boot.scr umount /mnt
```
as long as
EXT4-fs (mmcblk0p2): mounted filesystem with ordered data appears in the serial port mode
the root is successful, and the network port light is on after 5 seconds, and the computer can get 192.168.1.x.

5. Lazy one-click method (no change bootargs)

ophub has provided eMMC dedicated edition image
openwrt-rk3566-panther-x2-ext4-emmc.img.gzHTML176_ The cmdline in it is /dev/mmcblk0p2 by default. Download and work as usual

zcat *.img.gz | dd of=/dev/mmcblk0 bs=1M seek=4 conv=fsync

192.168.100.1 will be released after flashing the power-up, and even TTL will be saved.

6. Obstacle Clearance Quick Inspection Form

7. Summary

"TF card can run" only proves that the image is fine, eMMC 90% of the boot failures are due to image writing misalignment or root partition path error.
keep in mind that "seek=4" write disk + "root=/dev/mmcblk0p2" will be revived in place within ten minutes,
use the 32 GB high-speed eMMC to full use, and say goodbye to the USB flash drive. Happy flashing!

A piece of paper ...Reply

#12

When flashing, there is an error in writing the eMMC position, causing the system to not recognize the root partition, the kernel is directly stuck in initramfs, and the network cannot be started, which is really crashing!

3 个月前

Walking fishReply

#11

Ignoring the partition positioning when flashing, causing eMMC to fail to start, is really caught off guard. Fortunately, there is this note, otherwise it may really become a "brick".

Hongchen laughedReply

#10

Don't operate blindly when flashing, TF card can use eMMC but not work, it may be an image writing error or partition recognition problem, resulting in the system not being able to start, which is really a headache.

Contentment is al...Reply

You need to be extra careful when writing eMMC when flashing, as the wrong location or partition recognition failure will cause the system to fail to boot, which is really a headache. It is recommended to check more tutorials to avoid stepping on pitfalls.

Small bridge flow...Reply

When flashing, there is an error in the image position, resulting in eMMC startup failure and the network cannot be connected, which is really a trick! It is recommended to check the tutorial carefully to avoid similar problems.

4 个月前

Son of the windReply

The wrong write position when flashing caused eMMC to fail to start, which was really unexpected. The originally smooth TF card experience has become a "brick machine" in a blink of an eye, and the lesson is profound, so I must be more careful next time.

Night crawlerReply

Misoperation during flashing leads to eMMC failure, which is really a headache. TF card is fine, but eMMC is "lost", tossing for a long time or resurrecting on the spot, it's really tiring and angry.

The old man did n...Reply

I didn't check the partition settings carefully before flashing, and directly dd wrote to eMMC, which caused the system to fail to start, which was really a hole. It is recommended that you check more information to avoid similar problems.

It rains at nightReply

The image position of the eMMC written to the computer is wrong, causing the system to fail to boot, the network protocol stack to be loaded, and the computer to obtain the IP, which is really a headache.

Sword courage and...Reply

When flashing, there was an error in writing eMMC, causing the system to fail to boot and the network to be unable to connect, which was really devastating. It is recommended that novices pay more attention to the details of the operation to avoid the tragedy of "lost contact".

Life is like a dreamReply

When flashing, the dd command parameter error caused eMMC to fail to start, which was really frustrating. TF card is normal, but eMMC is directly bricked, the lesson is profound, be sure to confirm the parameters before operation!

The south wind kn...Reply

TF card can be used, but eMMC is "lost", which is really devastating. When flashing, the image is written in the wrong position, the root partition cannot be found, the kernel is directly stuck in initramfs, the network is not started, and the computer cannot be connected, which is simply a perfect case of operation error.

Black Panther X2 flashes OpenWrt: TF card can run, but eMMC is "lost"? A brick saving note takes you to revive in place in 10 minutes

1. Phenomenon review

2. Why does TF card work, but eMMC does not?

3. 30 seconds to determine where the stuck is

4. Three-step method of non-destructive brick rescue

(1) Confirm the eMMC device name

(2) with 4 MiB offset write mirror

(3) Let the kernel find the root partition

5. Lazy one-click method (no change bootargs)

6. Obstacle Clearance Quick Inspection Form

7. Summary

Comment List

Contact Us

Black Panther X2 flashes OpenWrt: TF card can run, but eMMC is "lost"? A brick saving note takes you to revive in place in 10 minutes

1. Phenomenon review

2. Why does TF card work, but eMMC does not?

3. 30 seconds to determine where the stuck is

4. Three-step method of non-destructive brick rescue

(1) Confirm the eMMC device name

(2) with 4 MiB offset write mirror

(3) Let the kernel find the root partition

5. Lazy one-click method (no change bootargs)

6. Obstacle Clearance Quick Inspection Form

7. Summary

Related Recommendations

Comment List

Contact Us