What to do if I have removed both partition in AIR-AP3802I-K-K9?

[richter5087]

I have accidently removed partition 1 & 2 during the uboot.

Now the AP boot loop with below.

____ _
/ ___|(_) ___ ___ ___
| | | |/ __| / __|/ _ \
| |___ | |\__ \| (__| (_) |
\____||_||___/ \___|\___/
_ _ ____ _
| | | | | __ ) ___ ___ | |_
| | | |___| _ \ / _ \ / _ \| __|
| |_| |___| |_) | (_) | (_) | |_
\___/ |____/ \___/ \___/ \__|
** LOADER **

U-Boot 2013.01-gad8bd06 (Sep 28 2017 - 17:03:04) SDK version: 2015_T2.0p10

Board: Barbados-3KVE
SoC: MV88F6920 Rev A1
running 2 CPUs
CPU: ARM Cortex A9 MPCore (Rev 1) LE
CPU 0
CPU @ 1800 [MHz]
L2 @ 900 [MHz]
TClock @ 250 [MHz]
DDR4 @ 900 [MHz]
DDR4 32 Bit Width,FastPath Memory Access, DLB Enabled, ECC Disabled
DRAM: 1 GiB
NAND: 256 MiB
SF: Detected MX25L3205D with page size 64 KiB, total 4 MiB
PCI-e 1 (IF 0 - bus 0) Root Complex Interface, Detected Link X1, GEN 2.0
PCI-e 2 (IF 1 - bus 1) Root Complex Interface, Detected Link X1, GEN 2.0

Map: Code: 0x3feda000:0x3ffae0f4
BSS: 0x3ffefb9c
Stack: 0x3f9c9f20
Heap: 0x3f9ca000:0x3feda000
U-Boot Environment: 0x00100000:0x00110000 (SPI)

Board configuration:
| port | Interface | PHY address |
|--------|------------|--------------|
| egiga1 | SGMII | 0x01 |
| egiga2 | SGMII | In-Band |
Net: , egiga1, egiga2 [PRIME]
Hit ESC key to stop autoboot: 0
Creating 1 MTD partitions on "nand0":
0x000000200000-0x000010000000 : "mtd=2"
UBI: attaching mtd1 to ubi0
UBIFS error (pid 0): mount_ubifs: can't format empty UBI volume: read-only mount
UBIFS error (pid 0): ubifs_mount: Error reading superblock on volume 'ubi:part1' errno=-30!

ubifsmount - mount UBIFS volume

Usage:
ubifsmount <volume-name>
- mount 'volume-name' volume
Unable to ubi mount UBIFS partition part1
Trying alternate partition part2
UBIFS error (pid 0): mount_ubifs: can't format empty UBI volume: read-only mount
UBIFS error (pid 0): ubifs_mount: Error reading superblock on volume 'ubi:part2' errno=-30!

ubifsmount - mount UBIFS volume

Usage:
ubifsmount <volume-name>
- mount 'volume-name' volume
Unable to ubi mount UBIFS partition part2
Giving up. Rebooting...
resetting ...

BootROM - 1.78
Booting from SPI flash, Secure mode
BootROM: RSA Public key verification PASSED
BootROM: CSK block signature verification PASSED
BootROM: Boot header signature verification PASSED
BootROM: Box ID verification PASSED
BootROM: JTAG is disabled

General initialization - Version: 1.0.0
Detected Device ID 6920
Master bootloder version 1.1e
High speed PHY - Version: 2.0
BoardId = 0x25board SerDes lanes topology details:
| Lane # | Speed| Type |
------------------------------|
| 1 | 0 | SGMII1 |
| 2 | 5 | PCIe1 |
| 4 | 5 | PCIe2 |
| 5 | 0 | SGMII2 |
-------------------------------
:** Link is Gen1, check the EP capability
PCIe, Idx 1: Link upgraded to Gen2 based on client cpabilities
:** Link is Gen1, check the EP capability
PCIe, Idx 2: Link upgraded to Gen2 based on client cpabilities
High speed PHY - Ended Successfully
DDR4 Training Sequence - Ver TIP-0.23.(Sublib 0.8)0
DDR4 Training Sequence - Switching XBAR Window to FastPath Window
DDR4 Training Sequence - Ended Successfully
BootROM: Image checksum verification PASSED
BootROM: Boot image signature verification PASSED

How can I restore back to make it work again?

[Rich R]

You can't because Cisco have never published a u-boot recovery image for 3802.
You will need to RMA the AP.

[Flavio Miranda]

@richter5087 

A couple of suggestion on this link

https://lihaifeng.net/?p=222

[Rich R]

@Flavio Miranda that assumes the AP still has a bootable partition.
If both partitions have been removed (as @richter5087 said) then changing boot variables or boot partition won't make any difference because there is nothing left to boot from.
The only way to recover from this is to re-flash the AP with a factory u-boot recovery image. Although Cisco have published the recovery image for the C9105/C9115/C9117/C9120/C9130 APs https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9120axi-access-point/217537-repairing-c9120-c9115-access-points-from.html#toc-hId-841267160 they have never provided the recovery image for the 2800 and 3800 APs.
You can see people have tried extensively https://community.cisco.com/t5/wireless/lets-figure-out-the-u-boot-flash-procedure-together-tac-unlocked/td-p/4447493 without any success (and some of the commands need a challenge token from TAC to unlock anyway).  The cases where people say "it worked" is where they still had at least 1 bootable partition which meant they could upgrade the normal way from TFTP with the AP tar file which is not the same as the AP not being bootable at all.
As you can see the answer from Leo is always: RMA - because that is the only option with these APs.