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diff --git a/docs/future/old.md b/docs/future/old.md deleted file mode 100644 index 5b5c40a0..00000000 --- a/docs/future/old.md +++ /dev/null @@ -1,221 +0,0 @@ -% Development notes (old/obsolete notes) - -For current notes, see [](./). - -These are old (obsolete) notes that mare kept because they might become -useful again in the future. - -Table of contents -================= - -- [X60 native graphics initialization (backlight - controls)](#x60_native_notes) - -- [T60 native graphics initialization (backlight - controls)](#t60_native_notes) -- [i945: 3D fix (based on 5927) for kernel 3.12+ on - 5320](#5320_kernel312fix) -- [i945/x60: coreboot 5927 testing (3D fix for kernel 3.12+ on replay - code)](#x60_cb5927_testing) - -X60 native graphics initialization (with backlight controls) {#x60_native_notes} -============================================================ - -**This is now obsolete. A better way was found (included in libreboot): -<http://review.coreboot.org/#/c/6731/>** - -***Also check [\#5320\_kernel312fix](#5320_kernel312fix) (to fix 3D on -kernel 3.12/higher)*** - -**The fix below was done on 5320/6 (from review.coreboot.org) but should -work just fine on later versions of 5320.** - -Native gpu init + backlight controls! (Fn keys). Also confirmed on X60 -Tablet (1024x768) and X60 Tablet (1400x1050) - -**Add backlight controls:** in *src/mainboard/lenovo/x60/devicetree.cb*, -change **gpu\_backlight** to **0x879F879E** - -That's all! **This has also been backported into libreboot 5th release -(line 1233 in src/mainboard/lenovo/x60/i915io.c)**. GNUtoo (Denis -Carikli) told me about the register **BLC\_PWM\_CTL** and that you could -set it to control backlight. I read that address using devmem2 while -running the VBIOS: - - # devmem2 0xe4361254 w - -The change is also included in libreboot 6. - -When doing this, it gave back that value. The same trick was used to get -backlight controls for T60 (see -[\#t60\_native\_notes](#t60_native_notes)). - -Further notes -------------- - -Reading **0xe4361254** (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 **lspci -vv** 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. **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.**. - -Intel-gpu-tools may prove useful for further debugging: -<http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/> - -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. - -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. **Note: this may not be correct; this person -says that their understanding is based on how the Lenote yeeloong -works**. - -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 - -phcoder (Vladimir Serbinenko) who is author of 5320 -(review.coreboot.org) talks about 'duty cycle limit' and 'flickering -frequency'. - -[Back to top of page](#pagetop) - -T60 native graphics initialization (with backlight controls) {#t60_native_notes} -============================================================ - -**This is now obsolete. A better way was found (included in libreboot): -<http://review.coreboot.org/#/c/6731/>** - -***Also check [\#5320\_kernel312fix](#5320_kernel312fix) (to fix 3D on -kernel 3.12/higher)*** - -**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** - -**Add backlight controls:** in *src/mainboard/lenovo/t60/devicetree.cb*, -change **gpu\_backlight** to **0x58BF58BE** - -Hold on! Check -[../misc/\#get\_edid\_panelname](../misc/#get_edid_panelname) to know -what LCD panel you have. This is important for the next step! - -Supported panels ----------------- - -[../hcl/\#supported\_t60\_list](../hcl/#supported_t60_list). - -See [\#lcd\_i945\_incompatibility](./#lcd_i945_incompatibility). - -[Back to top of page](#pagetop) - -i945: 3D fix (based on 5927) for kernel 3.12+ on 5320 {#5320_kernel312fix} -===================================================== - -**This is now obsolete. Merged in coreboot: -<http://review.coreboot.org/#/c/5927/>** - -**This needs to be rewritten (or better organized, or deleted?)**. This -is also now included in libreboot 6 (using the proper way, not the -7c0000 method which was a hack) - -**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.** - -See [\#x60\_cb5927\_testing](#x60_cb5927_testing) for the original (and -current) fix, for the replay code. Now we want to implement that on top -of <http://review.coreboot.org/#/c/5320> which is the current code for -native graphics initialization on i945. - -src/northbridge/intel/i945/gma.c (using the 7c0000 hack) on 5320: -[5320\_7c0000\_gma.c](dumps/5320_7c0000_gma.c) (rename it to gma.c, -replacing the current one). - -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. - -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). - -Here is some debugging output using intel\_gpu\_tools v1.2-1 (from -apt-get repositories) using tool "intel\_gtt": - -- kernel 3.14.4: - - with libreboot 5th release (using the 7c0000 gtt hack from - 5927/3): <http://paste.debian.net/104306> - - with coreboot+vgarom: <http://paste.debian.net/104309> -- kernel 3.2.0-60 (from apt-get repositories): - - with coreboot (no vbios or native init): - <http://paste.debian.net/104341> - -[Back to top of page](#pagetop) - -i945/X60: Coreboot 5927 testing (3D fix for kernel 3.12+ on replay code) {#x60_cb5927_testing} -======================================================================== - -**This is now obsolete. Merged in coreboot: -<http://review.coreboot.org/#/c/5927/>** - -**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.** - -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). - -**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.** - -Read the information on <http://review.coreboot.org/#/c/5927/>. - -For historical purposes, here is a collection of IRC logs that once -existed on this page, related to the issue: -[kernel312\_irc](dumps/kernel312_irc). - -PGETBL\_CTL differs between VBIOS (-) and native graphics init (+).\ -- PGETBL\_CTL: 0x3ffc0001\ -+ PGETBL\_CTL: 0x3f800001 - -GTT (graphics translation table) size is PGETBL\_save, max 256 KiB. BSM -(Base of Stolen Memory) is given by the bios. - -- 5927/7: [5927\_7.tar.gz](dumps/5927_7.tar.gz) (GRUB graphics are - correct now, and 3D still works) -- 5927/6: [5927\_6.tar.gz](dumps/5927_6.tar.gz) (GRUB graphics still - corrupt, 3D/everything still works after GRUB) -- 5927/5: [5927\_5.tar.gz](dumps/5927_5.tar.gz) (GRUB graphics - corrupt, 3D/everything still works after GRUB) -- 5927/3: [5927\_3.tar.gz](dumps/5927_3.tar.gz) (3D still works! - kernel 3.14.4) - the '7c0000' hack -- 5927/2: [5927\_2.tar.gz](dumps/5927_2.tar.gz) (3D works! kernel - 3.14.4) - the '7c0000' hack -- 5927/1 (didn't fix the 3D issue): - - [cbmem -c](dumps/5927_cbmemc) - - [/sys/class/drm/card0/error](dumps/5927_crashdump) - - [.config](dumps/5927_config) - -[Back to top of page](#pagetop) - -Copyright © 2014, 2015 Leah Rowe <info@minifree.org>\ -This page is available under the [CC BY SA 4.0](../cc-by-sa-4.0.txt) |