libreboot

Unnamed repository; edit this file 'description' to name the repository.
Log | Files | Refs | README

commit ff5b253757fd4d495dd8aa979d126a6bc16c2975
parent 4606722c5818b0927c1521293176cee522969258
Author: Andrew Robbins <andrew@libreboot.org>
Date:   Sat, 17 Mar 2018 01:46:00 +0000

Merge branch 'vbios-docs' of swiftgeek/libreboot into master

Diffstat:
www/faq.md | 26+++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/www/faq.md b/www/faq.md @@ -695,23 +695,23 @@ project. ### External GPUs -The Video BIOS is present on most video hardware. On all current -libreboot systems, this is implemented using free software. The Video -BIOS is responsible for initializing any sort of visual display; without -it, you'd have what's called a *headless* system. - -For integrated graphics, the VBIOS is usually embedded as an *option -ROM* in the main boot firmware. For external graphics, the VBIOS is +The Video BIOS is present on most video cards. For integrated graphics, +the VBIOS (special kind of OptionROM) is usually embedded +in the main boot firmware. For external graphics, the VBIOS is usually on the graphics card itself. This is usually proprietary; the -only difference is that SeaBIOS executes it (alternatively, you embed it +only difference is that SeaBIOS can execute it (alternatively, you embed it in a coreboot ROM image and have coreboot executes it, if you use a different payload, such as GRUB). -We're going to tentatively say no, they're not OK. Unless you're -actively working to replace the VBIOS, or find out how to get a visual -display without it (possible in some cases, if the kernel driver can be -modified to work without it, possibly only needing certain -non-executable data). +On current libreboot systems, instead of VBIOS, coreboot native GPU init is used, +which is currently only implemented for Intel GPUs. +Other cards with proper KMS drivers can be initialized once Linux boots, +but copy of VBIOS may be still needed to fetch proper VRAM frequency +and other similar parameters (without executing VBIOS code). + +In configurations where SeaBIOS and native GPU init are used together, +a special shim VBIOS is added that uses coreboot linear framebuffer. + ### EC (embedded controller) firmware