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diff --git a/docs/future/old.html b/docs/future/old.html deleted file mode 100644 index 16f1121..0000000 --- a/docs/future/old.html +++ /dev/null @@ -1,319 +0,0 @@ -<!DOCTYPE html> -<html lang="en"> -<head> - <meta charset="utf-8"> - <title>libreboot tutorials</title> - - <style type="text/css"> - @import url('../css/main.css'); - </style> - - <meta name="viewport" content="width=device-width, initial-scale=1.0"> - <meta name="author" content="glugman"> - <meta name="description" content="tutorials for libreboot, the reboot library."> - <meta name="robots" content="all"> -</head> - -<body> - - <div class="section"> - - <h1 id="pagetop">Development notes (old/obsolete notes)</h1> - <p> - For current notes, see <a href="index.html">index.html</a>. - </p> - - <p> - These are old (obsolete) notes that mare kept because they might become useful again in the future. - </p> - - </div> - - <div class="section"> - - <h1>Table of contents</h1> - <ul> - <li><a href="#x60_native_notes">X60 native graphics initialization (backlight controls)</a></li> - <li><a href="#t60_native_notes">T60 native graphics initialization (backlight controls)</a></li> - <li><a href="#5320_kernel312fix">i945: 3D fix (based on 5927) for kernel 3.12+ on 5320</a></li> - <li><a href="#x60_cb5927_testing">i945/x60: coreboot 5927 testing (3D fix for kernel 3.12+ on replay code)</a></li> - </ul> - - </div> - - <div class="section"> - - <h1 id="x60_native_notes">X60 native graphics initialization (with backlight controls)</h1> - - <p> - <b> - This is now obsolete. A better way was found (included in libreboot): <a href="http://review.coreboot.org/#/c/6731/">http://review.coreboot.org/#/c/6731/</a> - </b> - </p> - - <p> - <b><i>Also check <a href="#5320_kernel312fix">#5320_kernel312fix</a> (to fix 3D on kernel 3.12/higher)</i></b> - </p> - <p> - <b>The fix below was done on 5320/6 (from review.coreboot.org) but should work just fine on later versions of 5320.</b> - </p> - <p> - Native gpu init + backlight controls! (Fn keys). Also confirmed on X60 Tablet (1024x768) and X60 Tablet (1400x1050) - </p> - <p> - <b>Add backlight controls:</b> in <i>src/mainboard/lenovo/x60/devicetree.cb</i>, change <b>gpu_backlight</b> to <b>0x879F879E</b> - </p> - <p> - That's all! <b>This has also been backported into libreboot 5th release (line 1233 in src/mainboard/lenovo/x60/i915io.c)</b>. GNUtoo (Denis Carikli) - told me about the register <b>BLC_PWM_CTL</b> and that you could set it to control backlight. I read that address using devmem2 while running the VBIOS:<br/> - <b># devmem2 0xe4361254 w</b> - </p> - <p> - The change is also included in libreboot 6. - </p> - <p> - When doing this, it gave back that value. The same trick was used to get backlight controls for T60 (see <a href="#t60_native_notes">#t60_native_notes</a>). - </p> - - <h2>Further notes</h2> - <p> - Reading <b>0xe4361254</b> (address) in Lenovo BIOS always yields FFFFFFFF, even when writing to it (and writing to it doesn't affect brightness controls). - 'mtjm' on IRC found that the buttons (Fn keys) control /sys/class/backlight/acpi_video0 which has no affect on 61254 (BLC_PWM_CTL). This person says - intel_backlight has different values and uses the register. devmem2 works, needs checking <b>lspci -vv</b> for where the memory is mapped, - which is different than on coreboot; mtjm found that it was 0xec061254 on his system (X60 Tablet), and the register value is different too. - <b>This is relevant, because we still don't know how backlight controls are actually handled. We got it working by accident. We need to know more.</b>. - </p> - <p> - Intel-gpu-tools may prove useful for further debugging: <a href="http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/">http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/</a> - </p> - <p> - mtjm says 0xe4300000 is an MMIO region of the gpu (lspci -vv shows it), 0x61254 (BLC_PWM_CTL) is a documented register. Searching the kernel driver for backlight - shows that in intel_panel.c this register is used (there is an XXX comment about finding the right value, where recent kernels get it from. - </p> - <p> - What we want to do is calculate a good value, instead of setting it in devicetree.cb. mtjm says about backlight physics: - it has a light source , uses pulse width modulation (PWM) to turn it on/off, dimming is done by spending less time on. - <b>Note: this may not be correct; this person says that their understanding is based on how the Lenote yeeloong works</b>. - </p> - <p> - mtjm goes on to say, that the register specifies the frequency used for PWM in its depending on the GPU core frequency, so it - might be possible to calculate it without hardcoded laptop-specific values. Therefore, I am supposed to find out the 'display core frequency' - (mtjm says there might be a register for it; also, it might be in 5320 or the replay code) and the PWM modulation frequency. - https://en.wikipedia.org/wiki/Backlight#Flicker_due_to_backlight_dimming - </p> - <p> - phcoder (Vladimir Serbinenko) who is author of 5320 (review.coreboot.org) talks about 'duty cycle limit' and 'flickering frequency'. - </p> - - <p><a href="#pagetop">Back to top of page</a></p> - - </div> - - <div class="section"> - - <h1 id="t60_native_notes">T60 native graphics initialization (with backlight controls)</h1> - - <p> - <b> - This is now obsolete. A better way was found (included in libreboot): <a href="http://review.coreboot.org/#/c/6731/">http://review.coreboot.org/#/c/6731/</a> - </b> - </p> - <p> - <b><i>Also check <a href="#5320_kernel312fix">#5320_kernel312fix</a> (to fix 3D on kernel 3.12/higher)</i></b> - </p> - <p> - <b>The fix below was done on an earlier version of 5345 changeset (review.coreboot.org), but should work on the current version. it is included in libreboot 6</b> - </p> - <p> - <b>Add backlight controls:</b> in <i>src/mainboard/lenovo/t60/devicetree.cb</i>, change <b>gpu_backlight</b> to <b>0x58BF58BE</b> - </p> - <p> - Hold on! Check <a href="../misc/index.html#get_edid_panelname">../misc/index.html#get_edid_panelname</a> to know what LCD panel you have. This is important for the next step! - </p> - - <h2>Supported panels</h2> - <p> - <a href="../hcl/index.html#supported_t60_list">../hcl/index.html#supported_t60_list</a>. - </p> - - <p> - See <a href="index.html#lcd_i945_incompatibility">index.html#lcd_i945_incompatibility</a>. - </p> - - <p><a href="#pagetop">Back to top of page</a></p> - - </div> - - <div class="section"> - - <h1 id="5320_kernel312fix">i945: 3D fix (based on 5927) for kernel 3.12+ on 5320</h1> - - <p> - <b> - This is now obsolete. Merged in coreboot: <a href="http://review.coreboot.org/#/c/5927/">http://review.coreboot.org/#/c/5927/</a> - </b> - </p> - - <p><b>This needs to be rewritten (or better organized, or deleted?)</b>. This is also now included in libreboot 6 (using the proper way, not the 7c0000 method which was a hack)</p> - - <p> - <b>This was done on 5320/6 so far. The fix below is for 5320/6 which is now obsolete. This needs to be re-done for the latest version - of 5320. The fix below is (in practise) only for reference, therefore.</b> - </p> - - <p> - See <a href="#x60_cb5927_testing">#x60_cb5927_testing</a> for the original (and current) fix, for the replay code. Now we want - to implement that on top of <a href="http://review.coreboot.org/#/c/5320">http://review.coreboot.org/#/c/5320</a> - which is the current code for native graphics initialization on i945. - </p> - - <p> - src/northbridge/intel/i945/gma.c (using the 7c0000 hack) on 5320: <a href="dumps/5320_7c0000_gma.c">5320_7c0000_gma.c</a> (rename it to gma.c, - replacing the current one). - </p> - - <p> - The above is a hack (as is the original). A better (more correct) method is implemented in later versions of 5927, so - that should also be adapted for 5320. For now, you can use the above fix. - </p> - - <p> - The correct way to do it is to set gtt address to (end of stolen memory - gtt size), which is what later versions of 5927 do (successfully). - </p> - - <p> - Here is some debugging output using intel_gpu_tools v1.2-1 (from trisquel repositories) using tool "intel_gtt": - </p> - - <ul> - <li> - Trisquel 6. kernel 3.14.4: - <ul> - <li>with libreboot 5th release (using the 7c0000 gtt hack from 5927/3): <a href="http://paste.debian.net/104306">http://paste.debian.net/104306</a></li> - <li>with coreboot+vgarom: <a href="http://paste.debian.net/104309">http://paste.debian.net/104309</a></li> - </ul> - </li> - <li> - Trisquel 6. kernel 3.2.0-60 (from Trisquel repositories): - <ul> - <li>with coreboot (no vbios or native init): <a href="http://paste.debian.net/104341">http://paste.debian.net/104341</a></li> - </ul> - </li> - </ul> - - <p><a href="#pagetop">Back to top of page</a></p> - - </div> - - <div class="section"> - - <h1 id="x60_cb5927_testing">i945/X60: Coreboot 5927 testing (3D fix for kernel 3.12+ on replay code)</h1> - - <p> - <b> - This is now obsolete. Merged in coreboot: <a href="http://review.coreboot.org/#/c/5927/">http://review.coreboot.org/#/c/5927/</a> - </b> - </p> - - <p><b>The latest version as-is (5927/11) has not been tested by me yet. Always boot with 'drm.debug=0x06' kernel parameter when testing this.</b></p> - - <p> - This is the fix for 3D on kernel 3.12 and higher on i945 (ThinkPad X60 in this case). This is for the replay code. - Libreboot 5th release has a version of this backported already (based on 5927/3 using the '7c0000' hack). - </p> - - <p> - <b> - The replay code is obsolete (see 5320 changeset on review.coreboot.org for better version - which supports more systems/screens, and then 5345 for T60). Information here for reference since that is where the fix was first applied. - </b> - </p> - - <p> - Read the information on <a href="http://review.coreboot.org/#/c/5927/">http://review.coreboot.org/#/c/5927/</a>. - </p> - - <p> - For historical purposes, here is a collection of IRC logs that once existed on this page, related to the issue: - <a href="dumps/kernel312_irc">kernel312_irc</a>. - </p> - - <p> - PGETBL_CTL differs between VBIOS (-) and native graphics init (+).<br/> - - - PGETBL_CTL: 0x3ffc0001<br/> - + PGETBL_CTL: 0x3f800001 - </p> - - <p>GTT (graphics translation table) size is PGETBL_save, max 256 KiB. BSM (Base of Stolen Memory) is given by the bios.</p> - - <ul> - <li>5927/7: <a href="dumps/5927_7.tar.gz">5927_7.tar.gz</a> (GRUB graphics are correct now, and 3D still works)</li> - <li>5927/6: <a href="dumps/5927_6.tar.gz">5927_6.tar.gz</a> (GRUB graphics still corrupt, 3D/everything still works after GRUB)</li> - <li>5927/5: <a href="dumps/5927_5.tar.gz">5927_5.tar.gz</a> (GRUB graphics corrupt, 3D/everything still works after GRUB)</li> - <li>5927/3: <a href="dumps/5927_3.tar.gz">5927_3.tar.gz</a> (3D still works! kernel 3.14.4) - the '7c0000' hack</li> - <li>5927/2: <a href="dumps/5927_2.tar.gz">5927_2.tar.gz</a> (3D works! kernel 3.14.4) - the '7c0000' hack</li> - <li> - 5927/1 (didn't fix the 3D issue): - <ul> - <li><a href="dumps/5927_cbmemc">cbmem -c</a></li> - <li><a href="dumps/5927_crashdump">/sys/class/drm/card0/error</a></li> - <li><a href="dumps/5927_config">.config</a></li> - </ul> - </li> - </ul> - - <p><a href="#pagetop">Back to top of page</a></p> - - </div> - - <div class="section"> - - <p> - Copyright © 2014, 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. 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. - </p> - <p> - 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. 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