TP Link EAP245 V4

Hello Everyone,

i just got two TP-Link EAP245 V4. Is it possible to install OpenWRT on this device?
I have only found an image for the V3. Does anyone know what is the difference between V3 and V4 ?

Thanks for your help !

1 Like

I already know that this is not possible with the V3 image. I would love to know if support is planned, and what I can do to help progress on this. I already have V3's in use, and desperately need to integrate a V4...

1 Like

As a 1st step, open it up, see if it uses the same hw as the V3.

The eap245v4 is not the same as the eap245v3.

The EAP245V4 is based on a Mediatek MT7629AB (MediaTek MT7629 RFB1 board)
Wireless is based on MT7762N and MT7761N.

The ethernet ports seems to be driven by a RTL8367S
(Information from fcc website for the device containing internal photos of the device.

The cpu is a dual core ARMv7

$ cat /proc/cpuinfo
processor   : 0
model name	: ARMv7 Processor rev 3 (v7l)
BogoMIPS	: 40.00
Features	: half thumb fastmult edsp tls idiva idivt lpae evtstrm 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xc07
CPU revision	: 3

processor	: 1
model name	: ARMv7 Processor rev 3 (v7l)
BogoMIPS	: 40.00
Features	: half thumb fastmult edsp tls idiva idivt lpae evtstrm 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xc07
CPU revision	: 3

Hardware	: Generic DT based system
Revision	: 0000
Serial		: 0000000000000000

The system seems to have 16MB flash and 128Mb ram - same as the V3.
The flash layout is:

[    0.806706] mtk-nor 11014000.spi: w25q128 (16384 Kbytes)
[    0.812217] 8 ofpart partitions found on MTD device mtk_nor
[    0.817819] Creating 8 MTD partitions on "mtk_nor":
[    0.822706] 0x000000000000-0x000000080000 : "Bootloader"
[    0.828878] 0x000000080000-0x000000090000 : "Partition"
[    0.834928] 0x000000090000-0x0000000a0000 : "Factory"
[    0.840761] 0x0000000a0000-0x0000000b0000 : "Radio"
[    0.846510] 0x0000000b0000-0x0000000c0000 : "Extra"
[    0.852199] 0x0000000c0000-0x000000260000 : "Kernel"
[    0.857978] 0x000000260000-0x000000e40000 : "rootfs"
[    0.863677] mtd: device 6 (rootfs) set to be root filesystem
[    0.869417] 0x000000e40000-0x000000ff0000 : "Config"

The image from stock software seems to be based on lede. Full dmesg here.

Stock firmware can be found here: https://static.tp-link.com/upload/firmware/2023/202302/20230206/EAP245(EU)_V4_1.1.1%20Build%2020220908.zip

$ binwalk EAP245v4_1.1.1_\[20220908-rel31725\]_up_signed.bin 

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
8464          0x2110          Flattened device tree, size: 1437644 bytes, version: 17
8692          0x21F4          LZMA compressed data, properties: 0x6D, dictionary size: 8388608 bytes, uncompressed size: 4105860 bytes
1426512       0x15C450        Flattened device tree, size: 17290 bytes, version: 17
1446108       0x1610DC        Squashfs filesystem, little endian, version 4.0, compression:xz, size: 7245418 bytes, 684 inodes, blocksize: 262144 bytes, created: 2022-09-08 00:48:45

I should mention that I'm also very interesting in having OpenWrt support for EAP245V4. Let me know if there is anything I can do to help or test. I'm willing to test, but slightly concerned about bricking the device as I do not have a jtag or serial interface.

Looking at the contents of the mtd, the second mtd partition contains more detailed partition layout:
partition fs-uboot base 0x00000 size 0x80000
partition partition-table base 0x80000 size 0x02000
partition default-mac base 0x90000 size 0x01000
partition support-list base 0x91000 size 0x00100
partition product-info base 0x91100 size 0x00400
partition soft-version base 0x92000 size 0x00100
partition radio base 0xa0000 size 0x10000
partition extra-para base 0xb0000 size 0x10000
partition os-image base 0xc0000 size 0x1a0000
partition file-system base 0x260000 size 0xbe0000
partition user-config base 0xe40000 size 0x60000
partition mutil-log base 0xf30000 size 0x80000
partition oops base 0xfb0000 size 0x40000

The uboot partition contains
U-Boot SPL 2014.04-rc1-00395-g1a24601 (May 28 2020 - 19:56:21), and it seems to contain a webserver (at least lots of html/js) to allow reflash the image. I don't know how to activate it though - but chances are that a jtag / solder a serial port is not needed to de-brick the device.

Are there any good resources on how to build openwrt for new devices?

I'd also like to have OpenWrt support for the EAP245 v4. Please let me know if there is anything I can help with.

Start by picking an already existing device with the same hw, compile an initramfs for it, then boot it on the V4.
Observe the boot sequence, and check what works, and what doesn't.

Is it possible to load an initramfs from u-boot without a serial port?

you might be able to force a TFTP read, but it'll probably try to write the image you serve,
to flash, as it'll be treated as a recovery attempt.

so I'd say no, you can't

In 95% of all cases bootloader access via serial console will be a hard requirement for doing any kind of porting work, in 100% of all cases it's going to be veeeery risky to even try without serial console access. The ~5% inbetween only cover cases of extremely similar device variants (e.g. for different regions), which then rely on a lot of assumptions and luck to 'just work' - and you have to take the risk of total device loss (hard-brick), nothing you can rely upon.

tl;dr: serial console access to the bootloader is the first thing to ensure before you may even start thinking about porting OpenWrt to a new device, it's necessary - (almost) no exceptions.

2 Likes

I'd love to install openwrt on this device.

  • Is there any news on this?
  • How are the chances v4 will be supported? (Could a hardware donation help?)
  • How can I find "an already existing device with the same hw"? @frollic

I just bought this device without being aware I might buy v4 :frowning:

1 Like