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