From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stas Sergeev Subject: Re: Changing an app to use linux framebuffer Date: Sun, 01 Dec 2002 15:21:05 +0300 Sender: linux-msdos-owner@vger.kernel.org Message-ID: <3DE9FEB1.7070706@yahoo.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: linux-msdos@vger.kernel.org Cc: Simon Bridger <623402@despammed.com> Hello. Simon Bridger wrote: > I want to use it in a console window. Unfortunately I get a message > telling me there is no vesa driver. Known problem:( This largely depends on your video card however. Get a card where the extended registers are accessable via the VGA registers - and you have VESA. Old S3 and SiS cards will do. With a modern cards you are in troubles. > Autotrax uses plug-in graphic drivers, and we have the source for > these, and can easily change them. Will not help. > Is there any way of changing them to write directly into the linux > kernel frame buffer? There was a patch somewhere in the net which does this using SDL, but this patch seems to be dropped by its author:( This was also an emulation however, so, while being full-screen, it is still slow. > Or indirectly through some calls in the DOSEMU system? None currently available to deal with a frame buffer AFAIK. > Or to get the VESA drivers working? That was my goal during the 4 month recently. I've got VESA working, but, as the kernel have only 128 bit for the IO bitmap, you can't use an ioperm() syscall to open all the necessary extended registers of the card. So the trap/iopl()/decode_instr technique was used. This turned out to be even *much* slower than an xdos:( Fortunately the 2.5 kernels have a lazy IO bitmap allocation scheme, so that the size can be increased without any overhead. I haven't played with 2.5 kernels yet. If you really need to get VESA a go, you have to enlarge an IO bitmap to 8K there and I'll give you a code that enables VESA under dosemu. This work must be done sooner or later by someone anyway. I don't have time to play with a 2.5 kernel currently.