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* vga
@ 2012-07-11 14:52 sl
  2012-07-11 17:59 ` vga cinap_lenrek
  2012-07-11 18:06 ` vga cinap_lenrek
  0 siblings, 2 replies; 6+ messages in thread
From: sl @ 2012-07-11 14:52 UTC (permalink / raw)
  To: 9front

Have: 1920x1080 monitor
Problem: VESA BIOS contains no 1920x1080 modes
Question: How to use vga -m _without_ vesa?

Is this as simple as just choosing something else besides vesa?
Does realemu still need to be invoked when not using vesa?

When experimenting I've had inconsistent results so I'm
confused.

-sl

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: vga
  2012-07-11 14:52 vga sl
@ 2012-07-11 17:59 ` cinap_lenrek
  2012-07-11 18:29   ` vga sl
  2012-07-11 18:06 ` vga cinap_lenrek
  1 sibling, 1 reply; 6+ messages in thread
From: cinap_lenrek @ 2012-07-11 17:59 UTC (permalink / raw)
  To: 9front

-m vesa is just a hack to force the vesa driver. -m is
really the monitor to use from vgadb. normally, aux/vga
will try to determine the type of graphics card from
snooping the vga bios (looked up in vgadb) and then run
device specific driver code to set the desired video mode.

vgadb basicly matches some strings in the vga bios and lets
you coose and you parametrize the driver.

realemu is only used for vesa. native graphics driver doesnt
need to run vga bios code. native driver just programs the
various hardware registers to set the desired video mode and
then activates the kernel part of the video driver for stuff
like hardware bliting (acceleration), hardware cursors ect...
(if the driver supports that)

so using video without vesa means you need a graphics card
that plan9 has native drivers for (and some plumbing in
vgadb so it gets activated for your specific card... or 
you need to port / write a driver for it. vesa is kind of a
universal driver that doesnt know at all how to program the
hardware, but just runs some code stored in the vga bios under
the supervision of realemu passing thru memory and register
reads/writes to the real hardware.

--
cinap

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: vga
  2012-07-11 14:52 vga sl
  2012-07-11 17:59 ` vga cinap_lenrek
@ 2012-07-11 18:06 ` cinap_lenrek
  2012-07-11 18:30   ` vga sl
  1 sibling, 1 reply; 6+ messages in thread
From: cinap_lenrek @ 2012-07-11 18:06 UTC (permalink / raw)
  To: 9front

another way might be patching the vesa bios. if i remember
correctly the previous failures with nvidia card you had
where due to the kernel not recognizing the framebuffer
membars correctly and just mapping the addresses given by
vesa bios with size calculation done from the video mode
requested. when trying to switch to higher mode, the rest
of the framebuffer was not mapped causing kernel panic on
access. this was fixed a while ago but we didnt continue
with trying the bios patching trick...

--
cinap

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: vga
  2012-07-11 17:59 ` vga cinap_lenrek
@ 2012-07-11 18:29   ` sl
  0 siblings, 0 replies; 6+ messages in thread
From: sl @ 2012-07-11 18:29 UTC (permalink / raw)
  To: 9front

So, just use -m somethingbesidesvesa.

-sl

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: vga
  2012-07-11 18:06 ` vga cinap_lenrek
@ 2012-07-11 18:30   ` sl
  2012-07-11 23:38     ` vga cinap_lenrek
  0 siblings, 1 reply; 6+ messages in thread
From: sl @ 2012-07-11 18:30 UTC (permalink / raw)
  To: 9front

> this was fixed a while ago but we didnt continue
> with trying the bios patching trick...

I did continue, I just never hit upon the right combination.
Later, I moved operations to a different machine.

-sl

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: vga
  2012-07-11 18:30   ` vga sl
@ 2012-07-11 23:38     ` cinap_lenrek
  0 siblings, 0 replies; 6+ messages in thread
From: cinap_lenrek @ 2012-07-11 23:38 UTC (permalink / raw)
  To: 9front

damn. native driver would be better anyway. :)

--
cinap

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2012-07-11 23:40 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-07-11 14:52 vga sl
2012-07-11 17:59 ` vga cinap_lenrek
2012-07-11 18:29   ` vga sl
2012-07-11 18:06 ` vga cinap_lenrek
2012-07-11 18:30   ` vga sl
2012-07-11 23:38     ` vga cinap_lenrek

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