grub-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Multiboot video mode request on EFI-gop


From: Thomas Nilsen
Subject: Re: Multiboot video mode request on EFI-gop
Date: Mon, 16 Jan 2012 18:00:33 +0100

Ahh,, I found it!

This thing passed me by. In the multiboot_info header i was using vbe_modeinfo and got lfb from there..

I can see that a few bytes further into the array there is also a part

"
  multiboot_uint64_t framebuffer_addr;
  multiboot_uint32_t framebuffer_pitch;
  multiboot_uint32_t framebuffer_width;
  multiboot_uint32_t framebuffer_height;
  multiboot_uint8_t framebuffer_bpp;
"

that probably does what im asking for...

Trying it out now :)

2012/1/16 Thomas Nilsen <address@hidden>
Hi,

Please enlighten me. Im not quite sure i understand. Do you mean the os/kernel gets information about both "vbe" and "generic video" by grub when booted?

regards
Thomas


2012/1/16 Vladimir 'φ-coder/phcoder' Serbinenko <address@hidden>
On 16.01.2012 16:22, Thomas Nilsen wrote:
Hi,

I think i might have explained myself incorrect.

What i mean is:

1. Grub2 runs very well on BIOS & (U)EFI bios. Nice graphics as requested in gfxmode etc.

2. Grub2 loads multiboot kernel and gives it its requested videomode (from the videomode request part of multibootheader)

3. Grub2 does NOT load multiboot kernel and gives it its requested videomode. It seems to give it its mode, but the info is not right in the multiboot parameters.. So the "kernel" cannot tell what mode it is, where its LFB is and bpp etc.

Conclusion:

So what i think is happening (not happening) is that when using GOP and not VBE (for bios) then the updating of the multibootparams are not handled correctly.. It might be my mistake, but i cannot seem to get it working.. (might be my code that is not right..)

Did you notice that the structure for the generic video is different and pointed in another place than VBE one?
regards
Thomas

2012/1/16 Phillip Susi <address@hidden <mailto:address@hidden>>


   -----BEGIN PGP SIGNED MESSAGE-----
   Hash: SHA1

   On 1/16/2012 5:24 AM, Thomas Nilsen wrote:
   > Im thinking since its the efi-gop driver/module that handles video
   > mode on EFI boot this could probably be used when booting the same
   > way that vbe module does the change before executing the kernel.

   That's exactly what it is for.  Make sure you have that module loaded.

   > Im interrested in contributing on fixing this if someone with some
   > information can point me where to start off if someone knows whats
   > missing, or maby what is going wrong. I will start doing some
   > research aswell, but help is very much appreciated.

   If the GOP module is loaded and you are not satisfied with the video
   modes it provides, then AFAIK, you will need to either try a different
   motherboard ( that has a different EFI GOP implementation ) or get the
   specs for your video card and write your own EFI GOP driver.

   -----BEGIN PGP SIGNATURE-----
   Version: GnuPG v2.0.17 (MingW32)
   Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

   iQEcBAEBAgAGBQJPFDmDAAoJEJrBOlT6nu751w0IAK22Sr9ytvetkJRICpAILYXU
   vR2nPYXb5J8wHoUY3ooCtartmWv1bIs2TMcfjGWtwPyP0GCoJ/kH2XK8ZFx3MsAD
   uZGeKk5qP4x3XDEZvllreYm/tG1lv+Uwh6Bv7BFTGPA10BFFOv/5NRt0tn5RT3ke
   jR2/Fx+RKZ+haw//DhsC87RqhsQg53Wg3PnumpzWL9BU/pH4iajsE3FE8kck3eHK
   DUanFwDMIeu6e2+xPrDtgNdBGZEC0eUzCf5AMZYInCPZ1vJOYGrYGJaUBC6bD+wU
   2eHED1LKZ3kanPNnsP79AdtmOwFrJ94QW80Cy/hTqLk4bfPkRel9TKzDSJpeRWw=
   =J+5A
   -----END PGP SIGNATURE-----




_______________________________________________
Grub-devel mailing list
address@hidden
https://lists.gnu.org/mailman/listinfo/grub-devel


--
Regards
Vladimir 'φ-coder/phcoder' Serbinenko




reply via email to

[Prev in Thread] Current Thread [Next in Thread]