Date: Mon, 11 Aug 1997 11:49:04 -0700 From: Jonathan Mini <j_mini@efn.org> To: =?iso-8859-1?Q?S=F8ren_Schmidt?= <sos@sos.freebsd.dk> Cc: karpen@ocean.campus.luth.se, hfwirth@ping.at, emulation@FreeBSD.ORG Subject: Re: Fun with DOSCMD (was Re: modifying boot mgrs FROM FREEBSD) Message-ID: <19970811114903.20861@micron.efn.org> In-Reply-To: =?iso-8859-1?Q?=3C199708110641=2EIAA02115=40sos=2Efreebsd=2Edk=3E=3B_fro?= =?iso-8859-1?Q?m_S=F8ren_Schmidt_on_Mon=2C_Aug_11=2C_1997_at_08=3A41=3A4?= =?iso-8859-1?Q?8AM_%2B0200?= References: <19970810183126.27893@micron.efn.org> <199708110641.IAA02115@sos.freebsd.dk>
next in thread | previous in thread | raw e-mail | index | archive | help
Søren Schmidt stands accused of saying : > > 2) To truely allow full access to the VGA, we'd need to support things > > like the "x modes" (in appropriately named, Mode X was the original > > application of non-planar 256 color modes in VGA, see Dr. Dobbs, #178 > > Jul, 1991, p. 133. Interestingly enough, on page 32 there is one of the > > installments on the original 386BSD port. (This one talks about the > > bootstrap loader) you will need to allow the DOS app to set and read > > all of the VGA's registers. > > Now it gets tricky, there is no way in h... that we are going to emulate > all the regs etc in the VGA hw, its simply to complex and non std. Yes, my feelings exactly -- and allowing access to the real hardware is insane. > > 3) Assuming that you do allow that, how does the syscons handle > > switching away from video modes that are nonstandard, or possibly what > > it thinks is standard mode, but is not, if the dos app crashes or is > > killed? > > As long as the modes "just" use std VGA regs etc syscons has no problem > with that. But if you go beyond that all hell is going to break loose. Syscons has support for switching away-from/into the graphics modes? Last time I played with this (in VGA_320x200) syscons wouln't allow me to switch vtys. This was 2.2.1-R, so maybe I'm missing new code :) > > Basically, your answer becomes that of Linux's svgalib : You don't. You > > reboot your machine. Sorry, I don't accept that. > > > > You are asking more out of the syscons module than it can give you. > > Well, when/if we get the ability to run realmode from the kernel, we > can call the BIOS on the card. That way we can utilize the (hopefully) > onboard VESA layer. That will give what we need (and what I need for > syscons). Its then possible to either do a full VESA support, or > mimic some SVGA chipset for the basic functions. > > Give me the means to run realmode code from within the kernel, and I'll > teach syscons how to use it :) Hehe. I am working on it, however, you won't get realmode, just something similar -- a v86 thread with the mappings of real mode. It should be close enough :) (Currently, I am waiting on a motherboard that is held up in shipping due to a UPS strike -- once I get that motherboard, I'll finally have the crash box I need) > -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- > Søren Schmidt (sos@FreeBSD.org) FreeBSD Core Team > Even more code to hack -- will it ever end > .. -- Jonathan Mini (j_mini@efn.org) ... bleakness ... desolation ... plastic forks ...
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19970811114903.20861>