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diff --git a/docs/hcl/gm45_lcd.html b/docs/hcl/gm45_lcd.html new file mode 100644 index 0000000..9d85702 --- /dev/null +++ b/docs/hcl/gm45_lcd.html @@ -0,0 +1,297 @@ +<!DOCTYPE html> +<html> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + + <style type="text/css"> + @import url('../css/main.css'); + </style> + + <title>ThinkPad T500</title> +</head> + +<body> + + <div class="section"> + <h1 id="pagetop">LCD compatibility on GM45 laptops</h1> + + <p> + On the T400 and T500 (maybe others), some of the higher resolution panels + (e.g. 1440x900, 1680x1050, 1920x1200) fail in libreboot. + </p> + + <p> + <a href="index.html">Back to previous index</a>. + </p> + </div> + + <div class="section"> + <h1>The problem</h1> + <p> + In some cases, backlight turns on during boot, sometimes not. In all cases, + no display is shown in GRUB, nor in GNU/Linux. + </p> + <h1> + Current workaround: + </h1> + <p> + T500/R400 are clones of the T400. See <b>coreboot/src/mainboard/lenovo/t400/devicetree.cb</b> in libreboot, + and note that <b>register "gfx.lvds_dual_channel" = "0"</b> - in other words, single channel LVDS mode is + enforced. This works on the lower resolution panels (1280x800), but not on the higher ones. + </p> + <p> + For the high-res panels, re-compiling with <b>register "gfx.lvds_dual_channel" = "1"</b> partially solves + the problem for those displays; there is still no display in GRUB, but once the kernel takes over, there + is a display. + </p> + <p> + Linux (kernel) has its own init code (including EDID parsing). The current suspicion is that coreboot's + own initialization code has buggy EDID parsing in some way, such that the proper settings for the panel + are not used, leading to the failure. The actual graphics initialization does work. + </p> + </div> + + <div class="section"> + + <h2 id="edid">EDID</h2> + + <p> + One T500 had a screen (1920x1200) that is currently incompatible. Working to fix it. EDID: + </p> +<pre> +user@user-ThinkPad-T500:~/Desktop$ sudo i2cdump -y 2 0x50 +No size specified (using byte-data access) + 0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef +00: XX ff ff ff ff ff ff 00 30 ae 55 40 00 00 00 00 X.......0?U@.... +10: 00 11 01 03 80 21 15 78 ea ba 70 98 59 52 8c 28 .????!?x??p?YR?( +20: 25 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01 %PT...?????????? +30: 01 01 01 01 01 01 e7 3a 80 8c 70 b0 14 40 1e 50 ???????:??p??@?P +40: 24 00 4b cf 10 00 00 19 16 31 80 8c 70 b0 14 40 $.K??..??1??p??@ +50: 1e 50 24 00 4b cf 10 00 00 19 00 00 00 0f 00 d1 ?P$.K??..?...?.? +60: 0a 32 d1 0a 28 11 01 00 32 0c 00 00 00 00 00 fe ?2??(??.2?.....? +70: 00 4c 50 31 35 34 57 55 31 2d 54 4c 42 31 00 9a .LP154WU1-TLB1.? +80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +90: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +a0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +b0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +c0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +d0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +e0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +f0: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ +</pre> + <p> + What happens: backlight turns on at boot, then turns off. At no point is there + a working visual display. + </p> + + <p> + Another incompatible screen (EDID) 1680 x 1050 with the same issue: + </p> +<pre> +EDID: +00 ff ff ff ff ff ff 00 30 ae 53 40 00 00 00 00 +00 11 01 03 80 21 15 78 ea cd 75 91 55 4f 8b 26 +21 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01 +01 01 01 01 01 01 a8 2f 90 e0 60 1a 10 40 20 40 +13 00 4b cf 10 00 00 19 b7 27 90 e0 60 1a 10 40 +20 40 13 00 4b cf 10 00 00 19 00 00 00 0f 00 b3 +0a 32 b3 0a 28 14 01 00 4c a3 50 33 00 00 00 fe +00 4c 54 4e 31 35 34 50 33 2d 4c 30 32 0a 00 7e +Extracted contents: +header: 00 ff ff ff ff ff ff 00 +serial number: 30 ae 53 40 00 00 00 00 00 11 +version: 01 03 +basic params: 80 21 15 78 ea +chroma info: cd 75 91 55 4f 8b 26 21 50 54 +established: 00 00 00 +standard: 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 +descriptor 1: a8 2f 90 e0 60 1a 10 40 20 40 13 00 4b cf 10 00 00 19 +descriptor 2: b7 27 90 e0 60 1a 10 40 20 40 13 00 4b cf 10 00 00 19 +descriptor 3: 00 00 00 0f 00 b3 0a 32 b3 0a 28 14 01 00 4c a3 50 33 +descriptor 4: 00 00 00 fe 00 4c 54 4e 31 35 34 50 33 2d 4c 30 32 0a +extensions: 00 +checksum: 7e + +Manufacturer: LEN Model 4053 Serial Number 0 +Made week 0 of 2007 +EDID version: 1.3 +Digital display +Maximum image size: 33 cm x 21 cm +Gamma: 220% +Check DPMS levels +DPMS levels: Standby Suspend Off +Supported color formats: RGB 4:4:4, YCrCb 4:2:2 +First detailed timing is preferred timing +Established timings supported: +Standard timings supported: +Detailed timings +Hex of detail: a82f90e0601a1040204013004bcf10000019 +Did detailed timing +Detailed mode (IN HEX): Clock 122000 KHz, 14b mm x cf mm + 0690 06b0 06f0 0770 hborder 0 + 041a 041b 041e 042a vborder 0 + -hsync -vsync +Hex of detail: b72790e0601a1040204013004bcf10000019 +Detailed mode (IN HEX): Clock 122000 KHz, 14b mm x cf mm + 0690 06b0 06f0 0770 hborder 0 + 041a 041b 041e 042a vborder 0 + -hsync -vsync +Hex of detail: 0000000f00b30a32b30a281401004ca35033 +Manufacturer-specified data, tag 15 +Hex of detail: 000000fe004c544e31353450332d4c30320a +ASCII string: LTN154P3-L02 +Checksum +Checksum: 0x7e (valid) +WARNING: EDID block does NOT fully conform to EDID 1.3. + Missing name descriptor + Missing monitor ranges +bringing up panel at resolution 1680 x 1050 +Borders 0 x 0 +Blank 224 x 16 +Sync 64 x 3 +Front porch 32 x 1 +Spread spectrum clock +Single channel +Polarities 1, 1 +Data M1=2132104, N1=8388608 +Link frequency 270000 kHz +Link M1=236900, N1=524288 +Pixel N=9, M1=24, M2=8, P1=1 +Pixel clock 243809 kHz +waiting for panel powerup +panel powered up +</pre> + + <p> + For comparison, here is a working display (T400 screen, but was + connected to a T500. Some T500 displays also work, but no EDID + available on this page yet): + </p> +<pre> +EDID: +00 ff ff ff ff ff ff 00 30 ae 31 40 00 00 00 00 +00 12 01 03 80 1e 13 78 ea b3 85 95 58 53 8a 28 +25 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01 +01 01 01 01 01 01 26 1b 00 7d 50 20 16 30 30 20 +36 00 30 be 10 00 00 18 8b 16 00 7d 50 20 16 30 +30 20 36 00 30 be 10 00 00 18 00 00 00 0f 00 81 +0a 32 81 0a 28 14 01 00 30 e4 28 01 00 00 00 fe +00 4c 50 31 34 31 57 58 33 2d 54 4c 52 31 00 d8 +Extracted contents: +header: 00 ff ff ff ff ff ff 00 +serial number: 30 ae 31 40 00 00 00 00 00 12 +version: 01 03 +basic params: 80 1e 13 78 ea +chroma info: b3 85 95 58 53 8a 28 25 50 54 +established: 00 00 00 +standard: 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 +descriptor 1: 26 1b 00 7d 50 20 16 30 30 20 36 00 30 be 10 00 00 18 +descriptor 2: 8b 16 00 7d 50 20 16 30 30 20 36 00 30 be 10 00 00 18 +descriptor 3: 00 00 00 0f 00 81 0a 32 81 0a 28 14 01 00 30 e4 28 01 +descriptor 4: 00 00 00 fe 00 4c 50 31 34 31 57 58 33 2d 54 4c 52 31 +extensions: 00 +checksum: d8 + +Manufacturer: LEN Model 4031 Serial Number 0 +Made week 0 of 2008 +EDID version: 1.3 +Digital display +Maximum image size: 30 cm x 19 cm +Gamma: 220% +Check DPMS levels +DPMS levels: Standby Suspend Off +Supported color formats: RGB 4:4:4, YCrCb 4:2:2 +First detailed timing is preferred timing +Established timings supported: +Standard timings supported: +Detailed timings +Hex of detail: 261b007d502016303020360030be10000018 +Did detailed timing +Detailed mode (IN HEX): Clock 69500 KHz, 130 mm x be mm + 0500 0530 0550 057d hborder 0 + 0320 0323 0329 0336 vborder 0 + -hsync -vsync +Hex of detail: 8b16007d502016303020360030be10000018 +Detailed mode (IN HEX): Clock 69500 KHz, 130 mm x be mm + 0500 0530 0550 057d hborder 0 + 0320 0323 0329 0336 vborder 0 + -hsync -vsync +Hex of detail: 0000000f00810a32810a2814010030e42801 +Manufacturer-specified data, tag 15 +Hex of detail: 000000fe004c503134315758332d544c5231 +ASCII string: LP141WX3-TLR1 +Checksum +Checksum: 0xd8 (valid) +WARNING: EDID block does NOT fully conform to EDID 1.3. + Missing name descriptor + Missing monitor ranges +bringing up panel at resolution 1280 x 800 +Borders 0 x 0 +Blank 125 x 22 +Sync 32 x 6 +Front porch 48 x 3 +Spread spectrum clock +Single channel +Polarities 1, 1 +Data M1=1214600, N1=8388608 +Link frequency 270000 kHz +Link M1=134955, N1=524288 +Pixel N=10, M1=14, M2=11, P1=1 +Pixel clock 138857 kHz +waiting for panel powerup +panel powered up +</pre> + + </div> + + <div class="section"> + + <p> + Copyright © 2015 Francis Rowe <info@gluglug.org.uk><br/> + Permission is granted to copy, distribute and/or modify this document + under the terms of the GNU Free Documentation License, Version 1.3 + or any later version published by the Free Software Foundation; + with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. + A copy of the license can be found at <a href="../gfdl-1.3.txt">../gfdl-1.3.txt</a> + </p> + + <p> + Updated versions of the license (when available) can be found at + <a href="https://www.gnu.org/licenses/licenses.html">https://www.gnu.org/licenses/licenses.html</a> + </p> + + <p> + UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE + EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS + AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF + ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, + IMPLIED, STATUTORY, OR OTHER. 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