From c679b19f0b0d95f587b3836c7bf867a932d3df28 Mon Sep 17 00:00:00 2001 From: Leah Rowe Date: Mon, 22 Aug 2016 10:22:04 +0100 Subject: actually add the documentation directory. (I forgot git add in last commit) --- docs/future/index.html | 599 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 599 insertions(+) create mode 100644 docs/future/index.html (limited to 'docs/future/index.html') diff --git a/docs/future/index.html b/docs/future/index.html new file mode 100644 index 00000000..1a629865 --- /dev/null +++ b/docs/future/index.html @@ -0,0 +1,599 @@ + + + + + libreboot tutorials + + + + + + + + + + + +
+ +

Development notes

+

+ These are development notes, for future use. For old (obselete) notes, see old.html. +

+

+ Or go back to main task list. +

+ +
+ +
+ +

Table of contents

+ + +
+ +
+ +

standard test

+

+ These logs are usually obtained when testing changes related to graphics on i945 (X60 and T60). +

+ + +

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+ +
+ +
+ +

T60 cpu microcode

+ +

+ TODO: T60: find (for rare buggy CPUs that are unstable without microcode updates) if there is a workaround (patched kernel, special parameter, etc) So far, only 1 processor has been found to have issues. See microcode errata sheets http://download.intel.com/design/mobile/SPECUPDT/31407918.pdf and http://download.intel.com/design/mobile/SPECUPDT/30922214.pdf and then look at the debugging results collected in t7200q directory (q means quirk). +

+ +

+ Every other T7200 tested so far has worked without microcode updates. +

+ +

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+ +
+ +
+ +

i945 VRAM size

+ +

+ Apparently, only 8MB VRAM is available on i945 GPUs (though it could do 64MB):
+ phcoder: No. Hardware default is 8 MiB. When I wanted to make it configurable, I saw that docs mention only one other alternative: 1MiB. Later isn't event enough for 1024x768 at 24bpp without any acceleration or double buffering. It's possible that there are undocumented values. Which options do you have in vendor BIOS? + How to find out how much vram you have:
+ phcoder: TOM - BSM
+ phcoder: check what vendor BIOS offers as options
+ vimuser: I thought it could do 64MB usually
+ phcoder: not accorging to doc.
+ phcoder: see mobile-945-express-chipset-datasheet page 93
+ phcoder: see also src/northbridge/intel/i945/{early_init,northbridge,gma}.c
+ vimuser: "011 = DVMT (UMA) mode, 8 MB of memory pre-allocated for
+ vimuser: frame buffer."
+ vimuser: "Others - reserved"
+ phcoder: the easiest way is a loop at this position which tries different values and reads (and prints) BSM with them
+ stefanct: vimuser: they suggest that you change the value and look how BSM reacts to that
+ stefanct: as they pointed out earlier vram size = TOM - BSM
+ stefanct: different values of GMS
+ stefanct: phcoder: hm... this could be a hint. look at the text description of TOLUD at page 103
+ stefanct: it mentions 64 MB in the text about BSM as well
+ stefanct: table 18...
+ phcoder: stefanct: I have a guess which value make is 64 but I will not tell to avoid skewing test results
+ stefanct: phcoder: sure... i assumed you were not sure if it supports it at all. testing it properly is of course a good idea :)
+ stefanct: test the various possible (but reserved) values of GMS and see what the resulting VRAM size is
+ vimuser: so, TOM - BSM +

+

+ Back to top of page. +

+ +
+ +
+ +

LCD panels on i945 - fix incompatible panels

+ +

+ Fix T60 issues (see incompatible panels listed at ../hcl/index.html#supported_t60_list). +

+ +

+ Run that tool (resources/utilities/i945gpu/intel-regs.py) as root on systems with the offending panels in: +

+ + +

+ This shows values in devicetree.cb and src/northbridge/intel/i945/gma.c, the idea is that you run it on factory bios or vbios + and that it will (might) show different values: then you try those in the native graphics (in libreboot). +

+ +

+ Other values/registers might also need to be added to the script for these tests. +

+ +

+ check if intel_bios_reader from intel-gpu-tools reports the same value (BIOS has a hardcoded value) for PWM modulation frequency. + This file can read the VBIOS (64K dump). +

+ +

+ Check other tools in intel-gpu-tools aswell, compare outputs. Possibly add more information to intel-regs.py output (submit changes to mtjm). + Do oprom trace / replay (http://www.coreboot.org/User:GNUtoo#How_to_get_rid_of_the_vbios_of_the_x60_.5BNew_Version.5D) +

+ +

+ Study how EDID works and how gma.c handles it. +

+ +

+ Original getregs.py script can be found at http://hg.mtjm.eu/scripts/file/tip/intel-regs.py + written by Michał Masłowski. +

+ +

+ About fixing remaining LCD panels on 5345:
+ 'polarity' is mentioned in coreboot log (cbmem -c). compare output (with working and non-working panel). (and see the other notes in docs/future/index.html) +

+

+ There was a theory that working panels are + 6bpc (bits per colour) and nonworking are + 8bpc, but all EDIDs that we have here are + for 6bpc panels. +

+

We should compare coreboot logs + (from cbmem -c from systems with + working and nonworking panels.

+

How to dump EDID:

+

+ # apt-get install i2c-tools
+ # modprobe i2c-dev
+ Find out the correct ID to use:
+ # i2cdetect -l
+ Example:
+ # i2cdump -y 2 0x50 +

+ +

+ Working panel: EDID dump from LG-Philips LP150E05-A2K1: +

+
+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 43 40 00 00 00 00    X.......0?C@....
+10: 00 0f 01 03 80 1e 17 78 ea af 00 99 58 53 8c 2a    .??????x??.?XS?*
+20: 25 50 54 21 08 00 81 80 01 01 01 01 01 01 01 01    %PT!?.??????????
+30: 01 01 01 01 01 01 30 2a 78 20 51 1a 10 40 30 70    ??????0*x Q??@0p
+40: 13 00 31 e4 10 00 00 18 28 23 78 20 51 1a 10 40    ?.1??..?(#x Q??@
+50: 30 70 13 00 31 e4 10 00 00 18 00 00 00 0f 00 90    0p?.1??..?...?.?
+60: 43 32 90 43 28 14 06 00 32 0c 00 00 00 00 00 fe    C2?C(??.2?.....?
+70: 00 4c 50 31 35 30 45 30 35 2d 41 32 0a 20 00 9b    .LP150E05-A2? .?
+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    ................
+
+ +

+ Working panel: EDID dump from Boe-Hydis HT14P12-100 FRU: 13N7061 (Inverter FRU: 41W1010) +

+ +
+     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
+00: 00 ff ff ff ff ff ff 00 30 ae 22 40 00 00 00 00    ........0?"@....
+10: 00 0f 01 03 80 1c 15 78 ea af 40 95 56 4a 8f 25    .??????x??@?VJ?%
+20: 20 50 54 21 08 00 81 80 01 01 01 01 01 01 01 01     PT!?.??????????
+30: 01 01 01 01 01 01 30 2a 78 20 51 1a 10 40 30 70    ??????0*x Q??@0p
+40: 13 00 1d d6 10 00 00 19 25 23 78 20 51 1a 10 40    ?.???..?%#x Q??@
+50: 30 70 13 00 1d d6 10 00 00 19 00 00 00 0f 00 90    0p?.???..?...?.?
+60: 43 32 90 43 28 0f 01 00 09 e5 00 00 00 00 00 fe    C2?C(??.??.....?
+70: 00 48 54 31 34 50 31 32 2d 31 30 30 0a 20 00 3f    .HT14P12-100? .?
+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    ................
+
+ +

LTN141XA-L01: revert to libreboot git commit c943281 to see this

+ +

+ Non-working panel: EDID dump from Samsung LTN150XG-L08: +

+
+     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
+00: 00 ff ff ff ff ff ff 00 30 ae 40 40 00 00 00 00    ........0?@@....
+10: 00 0f 01 03 80 1f 17 78 ea 2d 05 97 57 51 8a 27    .??????x?-??WQ?'
+20: 23 50 54 21 08 00 01 01 01 01 01 01 01 01 01 01    #PT!?.??????????
+30: 01 01 01 01 01 01 64 19 00 40 41 00 26 30 18 88    ??????d?.@A.&0??
+40: 36 00 30 e4 10 00 00 19 28 15 00 40 41 00 26 30    6.0??..?(?.@A.&0
+50: 18 88 36 00 30 e4 10 00 00 19 00 00 00 0f 00 61    ??6.0??..?...?.a
+60: 43 32 61 43 28 14 01 00 4c a3 58 47 00 00 00 fe    C2aC(??.L?XG...?
+70: 00 4c 54 4e 31 35 30 58 47 2d 4c 30 38 0a 00 6d    .LTN150XG-L08?.m
+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    ................
+
+

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+ +
+ +
+ +

i945 gfx: X60/T60 VBT implementation (experimental: testing)

+ +

+ intel_bios_dumper in intel-gpu-tools seems interesting. +

+

+ Use 'drm.debug=0x06' kernel parameter when booting in grub! +

+

+ Before each test run, boot a live USB and delete the old logs in /var/log (kernel log, xorg log, dmesg and so on). +

+

+ Load (from the ROM) the runningvga.bin for each LCD panel on each system; do not execute it, only load it! (coreboot will have to be modified). + Rename the ROM appropriately, based on the system name and the panel name. coreboot_nativegfx_5868_plusrunningvga_t60_14_LTD141ECMB.rom, + for instance. Keep a copy for later use. +

+ +

You are supposed to:

+ + +

+ With each boot, make notes about what you see and get logs using the standard test. + You will need the files from #intelvbttool_results for each system. +

+ + Results (# means untested): + + +

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+ +
+ +
+ +

intelvbttool test results (VGA ROM dumps)

+

+ The VBIOS on i945 (intel gpu) platforms is self-modifying; that is, + its contents change when you run it. intelvbttool takes a dump of + the currently running vbios, and parses it. +

+ +

+ The idea is that we can extract the VBT tables using this knowledge, on the X60, X60 Tablet and T60 (Intel GPU). +

+ +

+ Here is an example of how VBT was implemented on the ThinkPad X230: + http://review.coreboot.org/#/c/5396. +

+ +

+ You'll need to build a T60 ROM with SeaBIOS and the VGA ROM (for Intel GPU). An X60 ROM is also needed (same configuration, using the VGA ROM for X60). +

+ +

+ T60 has DVI on its dock, make sure that the dock is attached when getting this output. +

+ +

+ Get intelvbttool here: http://review.coreboot.org/#/c/5842 (util/intelvbttool). +

+ +

+ Now dump a copy of the running VGA BIOS: + $ sudo dd if=/dev/mem bs=64k of=runningvga.bin skip=12 count=1
+ Then do (and record the output):
+ $ ./intelvbttool runningvga.bin > intelvbttool_out +

+ +

+ Backup both files (runningvga.bin and intelvbttool_out), renaming them to match the system and LCD panel used. + ../misc/index.html#get_edid_panelname will show you how to get the name (model) of the LCD panel used. +

+ +

Test results (# means untested and all had docks, unless noted).

+ + + +

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+ +
+ +
+ +

Fallback patches

+ + + +

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+ +
+ +
+ +

Other - unlisted (low priority)

+ + + +

Back to top of page.

+ +
+ +
+ +

+ Copyright © 2014, 2015 Leah Rowe <info@minifree.org>
+ 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 v1.2.3-70-g09d2