freebsd-dev/sys/isa/fdc.h
bde 9949885d48 Fixed error handling:
- Call isa_dmadone() whenever necessary to stop DMA and/or free bounce
  buffers.  Undead DMA corrupted the malloc freelist fairly consistently
  in the following configuration: SLICE kernel, 2 floppy drives, no disk
  in fd0, disk in fd1.
- Don't call fdc_reset() from fd_timeout().  Doing so gave an "extra"
  interrupt which was usually misinterpreted as being for completion
  of the next FDC command; the interrupt for completion of the next
  FDC command was then usually misinterpreted...  There were further
  complications for interrupts latched by the soft-spl mechanism so
  that they were delivered after all the h/w interrupts went away.
  This caused at least wrong head settle delays and may be why the
  FreeBSD floppy driver seems to munch floppies more than most floppy
  drivers.  The reset was unnecessary anyway in cases that didn't have
  the bug described next, since is was repeated a little later for
  the IOTIMEDOUT state.  The state machine has complications to handle
  resets correctly, so just use it.
- Don't call retrier() from fd_timeout().  The IOTIMEDOUT state needs
  to be processed next, and it isn't valid to set to that state if
  retrier() has aborted the current transfer.  Doing so caused null
  pointer panics after the previous bug was fixed.

Improved error handling:
- If an i/o is aborted, arrange to reset in the state machine before
  doing the next i/o.  New fdc flag for this.  This fixes spurious
  warnings and lengthy busy-waiting for the next i/o.
- Split STARTRECAL into RESETCOMPLETE and STARTRECAL and only check
  for the results from reset if we actually reset.  This fixes spurious
  warnings for other paths to STARTRECAL.  [Oops, it may break reset
  handling for motor-off resets.]

Cleanups in fd_timeout():
- Renamed to fd_iotimeout() to make it clearer that it is only used
  for i/o.
- Don't handle the bp == 0 case.  This case can't happen for i/o.
- Don't check for controller-busy.  We know it must be.
- Don't print anything.  retrier() already prints too much for normal
  errors.
- Fudge the state differently so that the state machine advances
  fdc->retry and the status is invalid (perhaps this should fudge a
  valid state like the one for WP).
- Style fixes.
1998-07-29 13:00:42 +00:00

87 lines
3.4 KiB
C

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)fd.c 7.4 (Berkeley) 5/25/91
* $Id: fdc.h,v 1.10 1998/07/11 06:35:39 bde Exp $
*
*/
enum fdc_type
{
FDC_NE765, FDC_I82077, FDC_NE72065, FDC_UNKNOWN = -1
};
/***********************************************************************\
* Per controller structure. *
\***********************************************************************/
struct fdc_data
{
int fdcu; /* our unit number */
int baseport;
int dmachan;
int flags;
#define FDC_ATTACHED 0x01
#define FDC_HASFTAPE 0x02
#define FDC_TAPE_BUSY 0x04
#define FDC_STAT_VALID 0x08
#define FDC_HAS_FIFO 0x10
#define FDC_NEEDS_RESET 0x20
struct fd_data *fd;
int fdu; /* the active drive */
int state;
int retry;
int fdout; /* mirror of the w/o digital output reg */
u_int status[7]; /* copy of the registers */
enum fdc_type fdct; /* chip version of FDC */
int fdc_errs; /* number of logged errors */
struct buf_queue_head head; /* Head of buf chain */
};
/***********************************************************************\
* Throughout this file the following conventions will be used: *
* fd is a pointer to the fd_data struct for the drive in question *
* fdc is a pointer to the fdc_data struct for the controller *
* fdu is the floppy drive unit number *
* fdcu is the floppy controller unit number *
* fdsu is the floppy drive unit number on that controller. (sub-unit) *
\***********************************************************************/
typedef int fdu_t;
typedef int fdcu_t;
typedef int fdsu_t;
typedef struct fd_data *fd_p;
typedef struct fdc_data *fdc_p;
typedef enum fdc_type fdc_t;
#define FDUNIT(s) (((s)>>6)&03)
#define FDTYPE(s) ((s)&077)