From 6742740ff0b7e84c359da0637b15cb1ae2f43af5 Mon Sep 17 00:00:00 2001 From: Francis Rowe Date: Sat, 11 Jul 2015 19:51:31 -0400 Subject: docs/hcl/gm45_lcd.html: standardize notes on GM45 LCD support --- (limited to 'docs/hcl/gm45_lcd.html') 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 @@ + + + + + + + + + ThinkPad T500 + + + + +
+

LCD compatibility on GM45 laptops

+ +

+ On the T400 and T500 (maybe others), some of the higher resolution panels + (e.g. 1440x900, 1680x1050, 1920x1200) fail in libreboot. +

+ +

+ Back to previous index. +

+
+ +
+

The problem

+

+ In some cases, backlight turns on during boot, sometimes not. In all cases, + no display is shown in GRUB, nor in GNU/Linux. +

+

+ Current workaround: +

+

+ T500/R400 are clones of the T400. See coreboot/src/mainboard/lenovo/t400/devicetree.cb in libreboot, + and note that register "gfx.lvds_dual_channel" = "0" - in other words, single channel LVDS mode is + enforced. This works on the lower resolution panels (1280x800), but not on the higher ones. +

+

+ For the high-res panels, re-compiling with register "gfx.lvds_dual_channel" = "1" partially solves + the problem for those displays; there is still no display in GRUB, but once the kernel takes over, there + is a display. +

+

+ 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. +

+
+ +
+ +

EDID

+ +

+ One T500 had a screen (1920x1200) that is currently incompatible. Working to fix it. EDID: +

+
+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    ................
+
+

+ What happens: backlight turns on at boot, then turns off. At no point is there + a working visual display. +

+ +

+ Another incompatible screen (EDID) 1680 x 1050 with the same issue: +

+
+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
+
+ +

+ 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): +

+
+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
+
+ +
+ +
+ +

+ Copyright © 2015 Francis Rowe <info@gluglug.org.uk>
+ 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 ../gfdl-1.3.txt +

+ +

+ Updated versions of the license (when available) can be found at + https://www.gnu.org/licenses/licenses.html +

+ +

+ 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. THIS INCLUDES, WITHOUT LIMITATION, + WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR + PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, + ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT + KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT + ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU. +

+

+ TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE + TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, + NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, + INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, + COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR + USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN + ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR + DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR + IN PART, THIS LIMITATION MAY NOT APPLY TO YOU. +

+

+ The disclaimer of warranties and limitation of liability provided + above shall be interpreted in a manner that, to the extent + possible, most closely approximates an absolute disclaimer and + waiver of all liability. +

+ +
+ + + -- cgit v0.9.1