Hello Friends

> > Hello All!
> > This is my first try in booting coreboot on a LVDS panel.
> > This is a Sandybridge-M system using video option ROM and VBT extracted 
> > from the original FW.
> if you ever want to get open-source gfx init running instead, let me know. It 
> would only need a few more lines to force a specific mode with libgfxinit, 
> maybe that is enough. And as you run the VBIOS ROM within coreboot, you are 
> probably not interested in a resident VBIOS, are you?
[JT]->[Nico] I would prefer to do it with just libgfxinit but I don't have a 
remote idea in how to initialize the LVDS panel.
[JT]->[Nico] With a desktop monitor libgfxinit just work in this system but not 
a sign of activity on the panel.
[JT]->[Nico] I would like to know how to initialize the panel with just 
coreboot, so, please show me how.
[JT]->[Subrata] But also would like to know how to do it the right way with the 
> > VBE: Getting information about VESA mode 4116
> What mode is this 4116? Are you sure, you need this specific mode? Are you 
> sure, your panel supports it? Sometimes, you need to specify a VBIOS (maybe 
> even VBT) specific code to use the panel's native resolution.
> [Subrata] VBE: resolution for 4116: 1024x768@16. Its depends on your panel 
> support and VBIOS support.
[JT] I just set at menuconfig 1024x768 1-5-5-5 and I have not idea why is 
reporting 4116-16 bit the intended is 18 bit.
[JT]->[Subrata] Do I need to configure something else or create some code for 

> > VBE: Function call failed!
> > Error: In vbe_get_mode_info function
> I don't think coreboot should halt here. Problems with the graphics are 
> non-fatal.
> [Subrata] Please have a look at 
> https://review.coreboot.org/c/coreboot/+/34284. What I found was sometime 
> Coreboot tries to fixed a mode which might not be supported by that VBIOS 
> hence we might see issue during payload and further because it would try to 
> map display to 0 resolution if mode set is not correct. Hence I had listed 
> the supported VESA mode in debug print. If you could try to use supported 
> one, it might work.

[JT] Halts with a "die" function because anyway if is not halted it will be 
halted by Tianocore with division by zero.
[JT]->[Subrata] The LVDS panel supports 1024x768 18 and 24 bit but the LVDS 
cable only can transfer 18 bits.
[JT]->[Subrata] The original FW support those LVDS resolutions too and I 
suppose VBIOS too.
[JT]->[Subrata] At 1024x768 1-5-5-5 is the only setting that shows signs of 
panel initialization and shows output on the panel but halts.
[JT] The other 2 1024x768 variants shows vertical stripes on the panel and gets 
halted anyway.
[JT] This system doesn't dump the list of supported VESA modes even if I 
comment the "die" function.

Thank you,
Jose Trujillo.
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