Unknown TP-Link header

I've been trying to build openwrt for a tp-link router(WDR8620v3) which is sold only in China. The header in the original OEM firmware doesn't look the standard tplink-v* headers so I'm kinda stuck with this.

Binwalk of the original firmware

$ binwalk wdr.bin

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
12960         0x32A0          U-Boot version string, "U-Boot 1.1.3 (Dec 22 2017 - 14:38:57)"
13008         0x32D0          CRC32 polynomial table, little endian
14236         0x379C          uImage header, header size: 64 bytes, header CRC: 0x492B0A68, created: 2017-12-22 06:38:59, image size: 29432 bytes, Data Address: 0x80400000, Entry Point: 0x80400000, data CRC: 0x220E3430, OS: Linux, CPU: MIPS, image type: Firmware Image, compression type: lzma, image name: "u-boot image"
14300         0x37DC          LZMA compressed data, properties: 0x5D, dictionary size: 8388608 bytes, uncompressed size: 67600 bytes
66560         0x10400         LZMA compressed data, properties: 0x6D, dictionary size: 8388608 bytes, uncompressed size: 4528128 bytes
1611368       0x189668        Squashfs filesystem, little endian, version 4.0, compression:xz, size: 5153198 bytes, 1356 inodes, blocksize: 262144 bytes, created: 2017-12-22 06:41:43

Here's the hexdump of the header

$ hexdump -C wdr.bin | grep -A 100 '00010200'
00010200  00 00 01 00 55 aa 9d d1  a8 c8 83 31 c9 69 fb bf  |....U......1.i..|
00010210  bc f0 d4 32 70 c7 aa 55  81 00 10 00 81 00 10 00  |...2p..U........|
00010220  00 00 00 00 00 00 00 09  00 00 00 00 00 01 d8 00  |................|
00010230  00 01 d8 00 00 00 08 00  00 01 e0 00 00 00 20 00  |.............. .|
00010240  00 02 00 00 00 01 00 00  00 03 00 00 00 01 00 00  |................|
00010250  00 04 00 00 00 00 02 00  00 04 02 00 00 17 92 68  |...............h|
00010260  00 1b 94 68 00 54 6b 98  00 70 00 00 00 10 00 00  |...h.Tk..p......|
00010270  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00010290  54 fa 07 36 3a 21 ea 5e  7c a1 36 e5 b6 d9 b6 fc  |T..6:!.^|.6.....|
000102a0  3d 60 3b 4d 01 29 64 6c  f2 45 a9 77 b7 cf e0 b8  |=`;M.)dl.E.w....|
000102b0  33 a9 57 7b 96 b6 46 7e  d9 16 0c 76 9a 77 e2 63  |3.W{..F~...v.w.c|
000102c0  57 44 52 38 36 32 30 56  33 00 00 00 00 00 00 02  |WDR8620V3.......|
000102d0  1f 8e 18 5d d1 45 b7 c9  ea e8 92 3b aa 17 16 c9  |...].E.....;....|
000102e0  39 92 8b 73 f2 30 70 c5  9d 4d 07 37 50 e1 31 5e  |9..s.0p..M.7P.1^|
000102f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00010400  6d 00 00 80 00 00 18 45  00 00 00 00 00 00 00 6f  |m......E.......o|
00010410  fd ff ff a3 b7 7f be 70  bf 82 86 e2 78 dc 5a 78  |.......p....x.Zx|
00010420  a3 4b cf d9 7a 37 7e 8f  38 ca 1d 92 3d 5d aa a5  |.K..z7~.8...=]..|
00010430  0a f5 b7 96 21 8e 37 57  82 55 95 74 a8 a9 14 9b  |....!.7W.U.t....|
00010440  60 96 e9 e6 d4 4b 40 27  bd a6 f2 9a 3c 34 a0 78  |`....K@'....<4.x|
00010450  5f fd 56 47 cc 4b 49 77  9f 0b 4d 46 88 45 a3 cd  |_.VG.KIw..MF.E..|
00010460  a3 eb 11 72 5b 57 9c d4  4d 68 80 82 e8 9d 01 2d  |...r[W..Mh.....-|
00010470  10 80 e1 4d 58 66 28 77  ef 4f 45 84 fb 70 00 71  |...MXf(w.OE..p.q|
00010480  64 14 b4 07 d8 e9 86 b6  9a 9d f9 f0 70 e8 f4 a8  |d...........p...|
00010490  27 d5 73 c8 c2 e7 fb 6b  be 15 2c f7 ec 0f fd 3e  |'.s....k..,....>|
000104a0  ab dd 99 7c c9 50 ac c0  06 50 71 43 7f ad ec 68  |...|.P...PqC...h|
000104b0  f0 ad 3d 61 9a 9d 32 ad  a4 ca a6 bd 4e 8a fd 66  |..=a..2.....N..f|
000104c0  39 39 b4 f6 a3 b4 23 50  4c b0 66 96 78 df 6c 12  |99....#PL.f.x.l.|
000104d0  4d a1 e0 8f 6c e4 a6 2c  eb 06 4d 97 76 09 40 93  |M...l..,..M.v.@.|
000104e0  79 74 e7 7b e4 1e 33 d2  6c e9 f6 58 98 e1 fe 73  |yt.{..3.l..X...s|
000104f0  20 05 9b d5 1e de a2 de  b6 0a 62 4d 43 c0 45 7a  | .........bMC.Ez|
00010500  62 61 d1 16 52 a8 cd a9  f2 83 71 92 29 c2 f3 01  |ba..R.....q.)...|
00010510  eb a0 30 a6 32 56 c7 da  d9 cd 8b 36 60 3b 24 90  |..0.2V.....6`;$.|
00010520  19 f5 fe 34 ca 7d 27 c5  2b 08 f3 e5 fe 1f b6 f2  |...4.}'.+.......|
00010530  c5 d3 f8 3b 23 06 e1 fd  12 24 5e 6b 43 a2 5b e9  |...;#....$^kC.[.|
00010540  da 6b 81 9e d3 2d 79 b9  a0 8e 82 d3 71 3e b9 5a  |.k...-y.....q>.Z|
00010550  66 a0 27 1e 1c 2a 2c 15  a8 f1 28 21 a9 a4 c8 61  |f.'..*,...(!...a|
00010560  22 5f 30 6d bd 75 27 e2  23 8a 83 c0 e5 35 a9 d0  |"_0m.u'.#....5..|
00010570  6c 91 1f 5c 6f fb c4 da  9c 41 b1 c9 da 6e 19 ec  |l..\o....A...n..|
00010580  a8 0e 8b 71 e5 6f 95 70  36 b4 ab 2d e8 1e 17 ce  |...q.o.p6..-....|
00010590  85 82 5f 8c 25 84 1b 25  10 68 ff b8 fb 67 ba e9  |.._.%..%.h...g..|
000105a0  23 87 5c 71 6a eb 01 84  ae 6b 95 97 db 8b 94 ec  |#.\qj....k......|
000105b0  52 80 89 8a 0f ad 4c ca  17 a8 f6 74 62 1e c8 f3  |R.....L....tb...|
000105c0  f1 25 84 4c e6 86 fb a6  9d 5e 3e 9c db b5 4c 63  |.%.L.....^>...Lc|
000105d0  f8 93 8c 2d 84 ed 62 0e  58 4f 43 97 59 83 05 aa  |...-..b.XOC.Y...|
000105e0  89 ae e7 b7 52 8e f2 ed  81 19 8e ba 34 ab 86 e5  |....R.......4...|
000105f0  1c ef 35 31 c6 ad 93 8e  70 88 bd f4 1e 2e 46 fe  |..51....p.....F.|
00010600  4e 23 7b c0 79 be 5e 10  b8 24 8a 4f e1 85 42 b9  |N#{.y.^..$.O..B.|
00010610  7e 37 8b 02 74 b7 9b fb  2b 40 b6 56 10 4e 5a 5c  |~7..t...+@.V.NZ\|
00010620  40 9d a0 38 51 a8 aa b8  a8 88 49 7b 3c 3e c7 50  |@..8Q.....I{<>.P|
00010630  a2 55 ab 43 f1 7c 86 f6  25 7b 5a a3 c0 da 12 f8  |.U.C.|..%{Z.....|
00010640  c5 8d 72 43 34 7c 8d 12  a0 01 3a ad 47 6d 80 20  |..rC4|....:.Gm. |
00010650  2c 74 6a 19 51 17 12 5c  bb 44 d5 65 c8 80 c2 af  |,tj.Q..\.D.e....|
00010660  bb 7a 9d fd c5 7f 68 53  ea 4d 21 26 ee 77 60 bf  |.z....hS.M!&.w`.|
00010670  1b fa 75 34 90 db cd c9  2c d8 0b 2b 16 d5 c5 7f  |..u4....,..+....|
00010680  32 0a 7d 20 2c 88 db a4  da 8b 63 61 ef e6 7e 1b  |2.} ,.....ca..~.|
00010690  39 b4 bf ac f6 68 fd 7a  45 66 62 39 11 8b 91 a9  |9....h.zEfb9....|
000106a0  f6 d5 99 2a b6 0f 1c e6  fe c5 08 8d c1 a1 7b 30  |...*..........{0|
000106b0  f1 ef 7e 49 f6 54 a2 a4  3b ca ac 2b 5e a8 06 6e  |..~I.T..;..+^..n|
000106c0  ad fd 21 0e 37 1b dd 9b  7e 1f 8c ac 71 ba f5 24  |..!.7...~...q..$|
000106d0  45 a6 17 23 83 2a 08 8c  84 d1 9f f8 6a 3b 92 10  |E..#.*......j;..|
000106e0  37 09 40 68 f9 e5 8a be  cf e6 5a b4 55 4d 5a 93  |7.@h......Z.UMZ.|
000106f0  9f f4 29 d1 01 02 34 e6  ab b1 ba 91 8f c2 dd ca  |..)...4.........|
00010700  e5 e6 57 17 79 bc c4 17  58 15 6b a3 82 e1 97 4f  |..W.y...X.k....O|
00010710  df 83 7d 5a 15 f8 c1 c6  0d f9 69 2d 90 03 96 70  |..}Z......i-...p|
00010720  b6 a6 64 4d fe 52 81 53  39 27 2e c8 b5 29 a8 3f  |..dM.R.S9'...).?|
00010730  39 83 cf 85 d4 8f 45 3b  c1 c3 52 c0 ba ec fc 37  |9.....E;..R....7|
00010740  fb 6f de f0 26 a3 61 dd  45 f0 64 89 fd ed df 8c  |.o..&.a.E.d.....|
00010750  50 05 d8 1a e0 24 0f 74  b8 d6 11 99 62 78 33 cb  |P....$.t....bx3.|
00010760  a7 7d 8b a3 f0 d2 9f d1  f5 a7 b4 ee d5 35 ed 85  |.}...........5..|
00010770  0c c4 0d 75 36 92 1c 6a  6c c1 b9 47 26 56 d9 bb  |...u6..jl..G&V..|
00010780  e9 2b 4f e6 1e 9b 12 3c  c5 47 33 c7 e7 12 be 13  |.+O....<.G3.....|
00010790  d0 9b 7e a1 c2 56 0c c1  57 eb b0 53 f7 be fc 2a  |..~..V..W..S...*|
000107a0  5b b2 3a e6 a9 bf 55 95  18 01 b2 80 30 b9 06 04  |[.:...U.....0...|
000107b0  38 8f ee e3 49 e5 f8 81  81 d1 50 52 89 9d 96 c5  |8...I.....PR....|
000107c0  79 30 f2 ca cc 83 5e 07  1b b1 e0 50 e6 64 ca 20  |y0....^....P.d. |
000107d0  97 14 3a f7 c7 10 0d a8  e9 49 ed e2 72 2f 72 81  |..:......I..r/r.|
000107e0  69 6f 65 f2 14 87 6a ce  b0 bf 2d 25 bd 3a 7d be  |ioe...j...-%.:}.|
000107f0  ce c7 62 4d 26 79 53 17  40 4c a7 dc 5f 02 90 48  |..bM&yS.@L.._..H|
00010800  ef e4 55 e8 60 53 2f 61  31 8c 08 d3 5a ab b5 68  |..U.`S/a1...Z..h|
00010810  7c 46 6c 92 38 ba 27 7f  3b a2 58 93 30 5a bb cb  ||Fl.8.'.;.X.0Z..|
00010820  69 83 b4 04 88 bb 24 46  ad d2 ba d4 7b 94 98 4d  |i.....$F....{..M|
00010830  39 f3 5b 6a 12 9a e4 22  6e 87 c8 12 38 12 fb e9  |9.[j..."n...8...|
00010840  60 7f eb ac 6b 64 33 bb  6b 9c 27 67 89 3f 82 e7  |`...kd3.k.'g.?..|
00010850  07 a0 ba 7a 4d 24 37 4b  ed 24 4a 58 53 e1 ec 24  |...zM$7K.$JXS..$|
00010860  87 15 4c 2f fc 0c bf 08  e7 ef 79 48 ae fe a9 26  |..L/......yH...&|
00010870  0e 83 c0 04 62 46 6a a9  f1 ae 8f ac ec 40 77 87  |....bFj......@w.|
00010880  39 6c 87 ce 0a a9 8d 93  d6 79 63 bd b3 6f ec e2  |9l.......yc..o..|
00010890  48 2f d7 6a c8 0a cf ab  25 9f 9d 55 08 f3 c2 02  |H/.j....%..U....|
000108a0  00 0c e7 bf 52 73 92 b8  4d 99 40 51 a6 50 e6 fa  |....Rs..M.@Q.P..|
000108b0  b7 a1 82 3f eb 6c 4b 23  26 c8 20 e9 04 c9 5f e8  |...?.lK#&. ..._.|
000108c0  8a e5 22 36 ab f1 c8 ac  d9 78 51 cd 92 e9 7e b3  |.."6.....xQ...~.|
000108d0  1a bd cd cf 62 15 76 39  d2 72 f7 50 51 8b d6 0c  |....b.v9.r.PQ...|
000108e0  9e 98 8d 8b 83 86 e1 c8  a8 d3 1d 02 41 0a bf ee  |............A...|
000108f0  35 6c bd 93 96 98 d5 a3  7f 65 79 49 9a e2 29 04  |5l.......eyI..).|
00010900  c5 39 4d 20 ee 92 9a 6b  26 44 1e 05 c4 63 47 94  |.9M ...k&D...cG.|
00010910  be 64 08 ab 21 df 3b ab  d7 23 5e 69 6e d6 5d fb  |.d..!.;..#^in.].|
00010920  18 6c 47 fc b5 96 28 ad  cc 46 39 96 c8 27 4d b5  |.lG...(..F9..'M.|
00010930  1c 5f 67 32 9e ea cc 87  39 d4 f9 b9 0f ad dc 96  |._g2....9.......|

It takes kernel load & entry addresses from 0x10218 & 0x1021c.

Any leads would be appreciated.

Here's the link to orginal thread Support for TP-Link WDR8620 V3

Put the binwalk too

the header is supposedly at 0x10200 with length 0x200

Edited the post with binwalk.

The situation with this board might be slightly similar. For now they using TFTP boot and flashing from there using serial. Probably you have to do the same for this one