Opened 11 years ago
Last modified 3 years ago
#10570 closed enhancement
Native video mode with VESA through vesa bios live patching — at Version 6
| Reported by: | pulkomandy | Owned by: | nobody |
|---|---|---|---|
| Priority: | normal | Milestone: | R1/beta4 |
| Component: | Drivers/Graphics/VESA | Version: | R1/Development |
| Keywords: | PatchVBios | Cc: | |
| Blocked By: | Blocking: | ||
| Platform: | All |
Description (last modified by )
This is a trick used in the Clover bootloader to get native video modes from VESA. The idea is to patch the VESA BIOS (which is shadowed in RAM) and replace the video mode tables with the EDID data.
This gets native video mode on ATI, NVidia and Intel cards, without the need to write an actual driver. Their Vesa BIOS is smart enough to accept any resolution in the table.
http://forum.voodooprojects.org/index.php/topic,1227.0.html
https://github.com/CloverHackyColor/CloverBootloader/blob/master/Library/VideoBiosPatchLib/
Change History (6)
comment:1 by , 10 years ago
| Description: | modified (diff) |
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comment:2 by , 8 years ago
| Component: | Drivers/Graphics → Drivers/Graphics/VESA |
|---|---|
| Keywords: | PatchVBios added |
comment:4 by , 6 years ago
Ha, it seems the VBE driver for NewOS that was donated to us (but left unused) in #7172 supports this also.
comment:5 by , 6 years ago
Note that the support is for specific BIOS kinds (one has to know how the resolutions are encoded to find what looks reasonably like modelines in the BIOS), I guess that driver only supports old nVidia cards. So the code in Clover is probably more useful these days?
comment:6 by , 4 years ago
| Description: | modified (diff) |
|---|
Clover link is dead, here's where it lives now: https://github.com/CloverHackyColor/CloverBootloader/blob/master/Library/VideoBiosPatchLib/VideoBiosPatchLib.c