From: Antonino Daplas <adaplas@pol.net>
To: Jon Smirl <jonsmirl@yahoo.com>
Cc: James Simmons <jsimmons@infradead.org>,
Linux Fbdev development list
<linux-fbdev-devel@lists.sourceforge.net>
Subject: Re: Reading the EDID block for x86 machines
Date: 13 Mar 2003 06:38:33 +0800 [thread overview]
Message-ID: <1047508652.1005.6.camel@localhost.localdomain> (raw)
In-Reply-To: <20030312181658.96700.qmail@web14912.mail.yahoo.com>
On Thu, 2003-03-13 at 02:16, Jon Smirl wrote:
> --- Antonino Daplas <adaplas@pol.net> wrote:
> > Unless I missed some imported BIOS calls or other
> > methods to do this or
> > something similar in real-mode...
>
> You missed something. The address of the VBIOS ROM can
> be controlled by writing to the PCI config space. You
> can make the ROM appear anywhere you want it to.
>
> This happens even for the boot video device.
> Somewhere very early in the boot the system BIOS
> enabled the VBIOS ROM and copied it to C000. This is
> the "shadow BIOS" option.
>
So the steps needed would be:
1. scan for pci devices looking for the vga controller type
2. if 1 is found other than the primary, disable the current controller
3. write to PCI config space of secondary controller the address you
want it to appear (ie C000:0000). Can I use other addresses?
4. enable the controller
5. far call c000:0003
6. disable the controller
7. repeat
Besides the finer points, did I miss anything obvious?
Tony
-------------------------------------------------------
This SF.net email is sponsored by:Crypto Challenge is now open!
Get cracking and register here for some mind boggling fun and
the chance of winning an Apple iPod:
http://ads.sourceforge.net/cgi-bin/redirect.pl?thaw0031en
next prev parent reply other threads:[~2003-03-12 22:41 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-03-11 12:49 Reading the EDID block for x86 machines Antonino Daplas
2003-03-11 15:49 ` James Simmons
2003-03-11 20:07 ` Antonino Daplas
2003-03-11 21:33 ` Antonino Daplas
2003-03-11 21:47 ` Antonino Daplas
2003-03-11 22:05 ` Jon Smirl
2003-03-11 22:33 ` Antonino Daplas
2003-03-11 22:54 ` Jon Smirl
2003-03-11 23:02 ` Antonino Daplas
2003-03-11 23:42 ` Jon Smirl
2003-03-12 17:38 ` Antonino Daplas
2003-03-12 18:16 ` Jon Smirl
2003-03-12 22:38 ` Antonino Daplas [this message]
2003-03-12 23:36 ` Jon Smirl
2003-03-12 23:47 ` Jon Smirl
2003-03-13 6:50 ` Geert Uytterhoeven
2003-03-13 15:42 ` Jon Smirl
2003-03-16 23:00 ` Antonino Daplas
2003-03-17 4:00 ` Jon Smirl
2003-03-17 7:00 ` Antonino Daplas
2003-03-17 19:33 ` Jon Smirl
2003-03-17 21:38 ` Antonino Daplas
2003-03-17 22:02 ` Jon Smirl
2003-03-17 22:29 ` Antonino Daplas
2003-03-17 23:41 ` Jon Smirl
2003-03-18 9:06 ` Geert Uytterhoeven
2003-03-18 10:00 ` Antonino Daplas
2003-03-18 17:07 ` Jon Smirl
2003-03-19 5:15 ` Antonino Daplas
2003-03-19 6:07 ` Jon Smirl
2003-03-18 0:00 ` Jon Smirl
2003-03-11 23:54 ` Jon Smirl
2003-03-12 12:10 ` Ville Syrjälä
2003-03-12 17:38 ` Antonino Daplas
2003-03-12 18:47 ` Ville Syrjälä
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1047508652.1005.6.camel@localhost.localdomain \
--to=adaplas@pol.net \
--cc=jonsmirl@yahoo.com \
--cc=jsimmons@infradead.org \
--cc=linux-fbdev-devel@lists.sourceforge.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).