Date: Wed, 30 Apr 1997 09:43:05 +0400 (MSD) From: =?KOI8-R?B?4c7E0sXKIP7F0s7P1w==?= <ache@nagual.pp.ru> To: Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp> Cc: CVS-committers@freebsd.org, cvs-all@freebsd.org, cvs-sys@freebsd.org Subject: Re: cvs commit: src/sys/i386/isa syscons.c Message-ID: <Pine.BSF.3.96.970430093233.723A-100000@nagual.pp.ru> In-Reply-To: <199704300218.LAA23808@zodiac.mech.utsunomiya-u.ac.jp>
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On Wed, 30 Apr 1997, Kazutaka YOKOTA wrote: > >ache 97/04/29 18:19:22 > > > > Modified: sys/i386/isa syscons.c > > Log: > > In comp_vgaregs skip cursor shape and 4 unused bytes (6 total) > > instead of 2 unused. > > Unused? > > I skipped the cursor position registers (CRTC registers 14 and 15). > You skipped the cursor shape registers (CRTC registers 10 and 11) and > the start address registers (CRTC registers 12 and 13). > > I agree that the cursor shape registers and the start address > registers may be set differently from the video mode parameter table > when the register values are read in scinit(). So, I don't object > skipping them when comparing register values in order to make some VGA > cards work. > > But, these registers ARE used to set up the card, aren't they? They are unused places in BIOS sense, not as VGA registers. I have few BIOS manuals from different sources where those 4 BIOS bytes marks as "unused". Maybe some BIOSes pay attention on what stored there (CRTC start & cursor position registers), but maybe some other not do it, so better skip this stuff. About cursor shape: I don't call them "unused", they just different for my card, but it isn't enough reason to zero video_mode_ptr since all other registers match. -- Andrey A. Chernov <ache@null.net> http://www.nagual.pp.ru/~ache/
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