From owner-freebsd-current Sat Sep 13 20:06:57 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id UAA16146 for current-outgoing; Sat, 13 Sep 1997 20:06:57 -0700 (PDT) Received: from zippy.dyn.ml.org (garbanzo@haiti-112.ppp.hooked.net [206.169.228.112]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id UAA16125 for ; Sat, 13 Sep 1997 20:06:50 -0700 (PDT) Received: from localhost (garbanzo@localhost) by zippy.dyn.ml.org (8.8.7/8.8.7) with SMTP id UAA02613 for ; Sat, 13 Sep 1997 20:07:05 -0700 (PDT) X-Authentication-Warning: zippy.dyn.ml.org: garbanzo owned process doing -bs Date: Sat, 13 Sep 1997 20:07:04 -0700 (PDT) From: Alex To: current@freebsd.org Subject: Re: Do *you* have problems with floppies? In-Reply-To: <199709132104.OAA20111@usr08.primenet.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk On Sat, 13 Sep 1997, Terry Lambert wrote: > Only the Intel 82077AA has FIFO's (the 82078 des to, but I don't > know what the heck it returns for a version ID -- anyone have one?). A quick web search revealed that Linux will identify four different "breeds" of 82078s (linux/drivers/block/floppy.c). > All other FDC chips with FIFO's are unprobeable, unless they > return a version ID. > > When you boot, you will see one of: > > fdc0: NEC 765 > fdc0: Intel 82077 > fdc0: NEC 72065B > fdc0: unknown IC type ff > > ...or *whatever* two digit hex value, other than 0x80, 0x81, or 0x90. > > The current driver code does not enable the FIFO. It would need to > have detected as an 82077, and then use the Configure command (0x13) > to clear bit 5 of command byte 2. It would set bits 0-3 to enable > a 16 byte threshold. Then it would need to use the Lock FIFO command > (0x94) to save the FIFO state across software resets. > > Then there would be additional code changes, as necessary, on top of > that. - alex