scsi_sii.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static char *sccsid = "@(#)scsi_sii.c	4.10      (ULTRIX)  3/13/91";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1988 by				*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any	other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or	reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/

/************************************************************************
 *
 * scsi_sii.c	05/03/90
 *
 * PVAX/FIREFOX/PMAX SCSI device driver (SII routines)
 *
 * Modification history:
 *
 * 03/12/91	Randall Brown
 *	Made a fix to sii_intr() if it was called do to a stray sii intr.
 *	The address of the chip must be setup.
 *
 * 02/13/91	Paul Grist
 *	Addded latent support for 2nd scsi controller on mipsmate.
 *
 * 02/12/91	Robin Miller
 *   o	Merge in PMAX wmbcopy(), rmbcopy(), & wmbzero() functions which
 *	John Gallant rewrote for the PDMA design.  These functions properly
 *	handle odd byte counts to/from the PMAX SCSI RAM buffer.
 *   o	Added two calls to wbflush() in function sii_reset() where the sii
 *	registers were modified, but were not being flushed.
 *
 * 01/29/91	Robin Miller
 *   o	Setup address/count for various CD-ROM commands which require
 *	data in/data out.
 *   o	Added support for disk send/receive diagnostic functions.
 *
 * 11/21/90	Robin Miller
 *   o	Added support for 10-byte Read/Write CDB's.
 *   o	Use function sz_cdb_length() to obtain the Command Descriptor
 *	Block (CDB) length.
 *
 * 09/26/90	Robin Miller
 *	Fixed problem introduced in 8/29/90 edit.  I inadvertantly left
 *	off the target ID index when referencing the SII DMA count field
 *	(sc_siidmacount[targid]) on disconnect phases.  This would have
 *	caused problems when multiple drives disconnected at the same time.
 *
 * 08/30/90	Robin Miller
 *	Added check in probe routine to recognize RX26 device type
 *	and setup accordingly for floppy device.
 *
 * 08/29/90	Robin T. Miller
 *	Changed the check made in sii_msgin() to set the SZ_DMA_DISCON
 *	flag (disconnect occured during dma) when there is residual dma
 *	count for this target.  Previously, this flag was only set if
 *	the previous phase was a data in or a data out.  This check was
 *	insufficient for our CDROMs, broke both the RRD40 & RRD42, since
 *	the previous two phases were message in.
 *
 * 08/07/90     Richard L. Napolitano 
 *      (First Ultrix modification)
 *      In the routine sii_select_target, we must flush the write
 *      to the sii_slcsr register before writing the sii_comm 
 *      register to start selection. This change insures that the
 *      SCSI id of the target is written to the SII prior to starting 
 *      selection.
 *
 * 07/16/90     Janet L. Schank
 *      During selection of a target, it was possible for a reselection
 *      to occur after the ATN line was raised.  The RDAT is broken
 *      and can't deal with this.  So during the selection process,
 *      reselections are now disabled.  This is a slight performance
 *      hit, so if the RDAT is ever fixed this hack should be removed.
 * 
 * 06/04/90	Bill Dallas
 *	In sii_startdma() got rid of a hard define of SZ_RQSNS_LEN. 
 *	Used the scsi command packet for the length.
 *
 * 05/30/90     Janet L. Schank
 *      Modified to use kn230_bzero, kn230_rbcopy, and kn230_wbcopy.
 *
 * 05/14/90     Janet L. Schank
 *      Added Mipsmate rambuffer copy and zero functions to deal with the
 *      hardware bug.
 *
 * 05/03/90	John A. Gallant
 *	Cleaned up a lot of the SCSI bus RESET/clear_io_tasks problems.
 *	removed the bug on sync xfers and RESET in sii_intr.  Removed the
 *	clear io call in sii_scsistart.
 *
 * 03/19/90	John A. Gallant
 *	Placed the setting/clearing of the req/ack offset control register
 *	for the SII in the state change code and in the selection code.
 *	Now sii_dmctrl is set prior to any data phases occuring.
 *
 * 03/14/90	John A. Gallant
 *	Added checks within the data moving code to not go past the true
 *	end of the user's buffer for reads and writes.  Added zero fill
 *	for writes less than a sector size.
 *
 * 01-Mar-90    Janet Schank
 *      Added retries on busy target in the probe routine.
 *
 * 20-Dec-89    Janet L. Schank
 *      Fixed the "sc" initialization bug in probe.  Replaced sii_nNSII
 *      with nNSII.  Moved sii_stray_intr to scsi_data.c.
 *
 * 12-Dec-89    Mitch McConnell
 *	Initialize sc_attached to zero.
 *
 * 01-Dec-89	Fred Canter
 *	Calculate the number of PTEs needed to double map the user's
 *	buffer in a machine independant way (no more magic number).
 *
 * 02-Nov-89    Janet L. Schank
 *      Added a call to sii_clear_discon_io_tasks in sii_reset.
 *      This will clear all active and disconnected IO requests.
 *      Fixed wmbzero clearing error, wasn't clearing all that was needed.
 *
 * 17-Oct-89    Janet L. Schank / JAG
 *      During the message in phase, if an unsupported extended message
 *      is received, ATN is asserted before the last message byte
 *      is acknowledged.  In message out, if polled mode, really send
 *      an identify with NO disconnects.  Added a call in the probe routine
 *      to get_scsiid.
 *
 * 08-Oct-89	Fred Canter
 *	Remove error log #ifdef OLDWAY.
 *
 * 07-Oct-89	Fred Canter
 *	Save removable media bit from inquiry data in sz_softc.
 *
 * 03-Oct-89	Fred Canter
 *	Added error log debug code (#ifdef ELDEBUG). This allows the
 *	driver to produce most error types for uerf debuging.
 *
 * 09/22/89     Janet L. Schank
 *      Changed some defines and ifdefs to include and use sii.h.
 *      Removed alot of "ifdef vax"'s.  The softc structure is now used 
 *      in the same way as on the vax-side.  Replaced siiprobe with
 *      sii_probe taken from the vax code.  The sii reg. addr. is
 *      received as an argument to sii_probe and is saved in the softc
 *      structure, which is then used for all further refrences to
 *      "scsiaddr".
 *
 * 24-Aug-89	Alan Frechette
 *	Added routine siireset() to reset the SII chip for the
 *	crash dump code in order to always get crash dumps. This
 *	is needed for the PROM boot drivers to work correctly.
 *
 * 15-Jul-89	Fred Canter
 *	Merged Dynamic BBR and error log changes.
 *
 * 11-Jul-89	Fred Canter
 *	Convert error messages from printf to scsi_logerr().
 *	Save status byte for current command for error log.
 *	Modify sii_dumpregs() for use by sii_logerr().
 *
 * 27-Jun-89	John A. Gallant
 *	Added the initialization of the completion code routine pointers.  In
 *	the start dma code added support for the read/write long commands.
 *
 * 24-May-89	Fred Canter
 *	Changes to match the new, more general rzdisk utility.
 *	Changed the mode select data structures so an address and
 *	length are passed with the ioctl. This allows pages to be
 *	added to rzdisk without requiring a kernel rebuild.
 *
 * 04/13/89	John A. Gallant
 *	Removed the b_command fixup in sii_busy_target().
 *
 * 03/22/89	John A. Gallant
 *	Able to handle a target returning a status of busy.  The command is
 *	left on the queue and after a BUS_WAIT time is restarted.  The start
 *	dma routine for mode select uses the parameter length in the CDB for
 *	the data count.  The select target routine checks the SII to determine
 *	if it can start a selecton command.
 *
 * 03/01/89	John A. Gallant
 *	Added the pseudo command codes for to allow the tape to unload.  I
 *	followed the same conventions as the firefox/pvax code.  The start/stop
 *	command was changed to a pseudo command.
 *
 * 01/16/89	John A. Gallant
 *	Improved the Selection code, made it more forgiving.  If selection 
 *	fails, the SII is checked to see if it is being reselected.
 *
 * 12/21/88	John A. Gallant
 *	In sii_recvdata() during a dma transfer, the MIS bit is also checked
 *	to watch for the target changing phase.  When the MIS bit is set the
 *	WAIT loop will terminate.
 *
 * 12/20/88	John A. Gallant
 *	During the probe routine, the siidboff[] region is cleared.  This
 *	removes the previous inquiry data that was put there.  Introduced a 
 *	new routine, wmbzero().  It writes 0 to the ram buffer.
 *
 * 12/15/88	John A. Gallant
 *	Modified the wait for CON in sii_state_change(), only wait if
 *	a connect is expected.  Also in the same routine, if CON is not
 *	set bus_idle is set to TRUE, immediatly.
 *
 * 12/13/88	John A. Gallant
 *	Added the changes from firefox:
 *	Had to make a change due to new firmware in CDROM. The CDROM
 *	now sends a message reject message and then disconnects from
 *	the bus when you send it an Extended Synchronous Data Tranfer
 *	Request Message. This is now handled correctly.
 *	
 * 11/21/88	John A. Gallant
 *	Changes to help the "slower" tape drive, in select_target, returns
 *	ABORT, in scsistart the spin loop breaks out and returns IP.
 *	Revamped the debug statements to be able to track a single target.
 *
 * 11/09/88	John A. Gallant
 *	Started the merge with the V3.0 source level.  Due to time constraints
 *	only the changes for the new IOCTL support will be merged.  Others
 *	changes will hopefully occur as time permits.  
 *
 * 11/09/88	Alan E. Frechette
 *	The following fixes were made to support the CDROM device:
 *	1: Call "sii_dodev()" in probe for CDROM device.
 *	
 *	2: Ignore the second disconnect if we get back-to-back 
 *	   disconnects from the CDROM device. 
 *
 *	3: Fixed the routine "sii_select_target" to handle the
 *	   slower CDROM device. Wait for the connect bit (SII_CON)
 *	   after we get the state change bit (SII_SCH). 
 *
 *	Had to change a few things to get "rzdisk" to work but they
 *	were minor.
 *
 *   COMMENTS from V3.0:
 *   03-Nov-88	Alan Frechette
 *	Added in support for disk maintainence. Added the commands
 *	FORMAT UNIT, REASSIGN BLOCK, READ DEFECT DATA and VERIFY DATA.
 *	Made changes to MODE SENSE and MODE SELECT. 
 *
 *  11/07/88	John A. Gallant
 *	The sii_scsistart routine now returns success/or error condition.  This
 *	allowed the state machine to handle error conditions correctly, this
 *	is very useful for tape and filemarks.
 *   COMMENTS from V3.0:
 *   03-Nov-88	Alan Frechette
 *	.............................................. If a scsi command
 *	did not have good status then return the value "SZ_RET_ERR"
 *	in "sii_scsistart()" otherwise return "SZ_SUCCESS". This
 *	was a nasty bug.
 *
 *  7-Sep-88	Ricky Palmer (rsp)
 *	Did some major re-writing of this code for PMAX. Basically
 *	had some major race conditions on the new architecture/processor
 *	as well as some delays due to how original code was constructed.
 *	I re-wrote the interrupt routine to be single threaded and
 *	not looping. I also updated the pieces of this code that
 *	came from Mike Nielsen as he found bugs in his original
 *	SCSI code that had made their way into this code. Larry Palmer
 *	suggested the new buffer scheme that allows this code to
 *	now support 7 devices plus the host adaptor with normal
 *	transfer requests upto 64KB from the minphys code. Some
 *	other changes were targeted at getting performance up
 *	by a factor of 1.5 to 3.0 depending on the request size.
 *	Also added support for the RZ23 as what was here did not
 *	work correctly. Thanks also goes to Larry Palmer for his efforts
 *	in tracking various bugs and problems along with me.
 *	We both spent considerable time architecting, writing new and 
 *	re-writing old code to make this really work for PMAX.
 *
 * 23-Aug-88	Alan Frechette
 *	Fixed the GENERIC kernel boot problem for the SII on FIREFOX.
 *	The GENERIC kernel now boots off a FIREFOX workstation.
 *
 *	Added support to handle SYNCHRONOUS and ASYNCHRONOUS devices
 *	at the same time. I simply save the req/ack offset for each
 *	SCSI device out on the bus after issuing the Synchronous Data
 *	Transfer Request extended message. The req/ack offset is used
 *	to set the DMA Control Register of the SII for synchronous or
 *	asynchronous data transfers.
 *
 *	Fixed a few bugs in the SII interrupt routine dealing with
 *	reselects and handle quick reselects there rather then wait
 *	for another interrupt.
 *
 * 17-Aug-88	Fred Canter
 *	Created this file by moving the SCSI SII specific files
 *	from the old combined driver (scsi.c) to scsi_sii.c.
 *	The SII code was written by Darrell Dunnuck and Alan Frechette.
 *
 * 01-Aug-88 -- Ricky Palmer
 *      Ifdef'ed and modified for mips and vax. Wrote some sii code and
 *	also picked up sii code from Mike Nielsen/Alan Frechette/
 *	Fred Canter/Darrell Dunnuck/Larry Palmer/Bob Rodriguez.
 *
 ***********************************************************************/

#include "../data/scsi_data.c"

/*
 * Define ELDEBUG to create error for uerf debuging.
 * NOTE: must not be defined at submit time (performance hit).
 */
/*#define	ELDEBUG	*/

#include "scsi_debug.h"
int siidebug = 0;
int siitarget = 0;

#ifdef vax
extern char cvqmsi[] [512*NBPG];
extern char cvqmsirb[];
#endif vax
extern char szbufmap[];
extern short sz_timetable[];
extern int cpu;

int sii_wait_after_inquiry = 1000;

/* For quick hacks at debugging. */
#undef DEBUG

int sii_busy_target();			/* for forware reference */
int wmbcopy(), rmbcopy(), wmbzero(), bzero(), bcopy();
extern int kn230_bzero(), kn230_wbcopy(), kn230_rbcopy();

/******************************************************************
 *
 * Probe routine for SII chip.
 *
 ******************************************************************/
short sii_reject_message = 0;
short sii_assert_attn = 0;		/* Assert Attention Flag    */

/*
 * Number of seconds to wait for SCSI devices
 * to come ready enough to respond to inquiry
 * after bus reset. Needs to be a variable so
 * users can change it (I am such a nice guy).
 * Factory default is 7 seconds (in scsi_data.c).
 */
extern int sz_wait_for_devices;
extern int sz_max_wait_for_devices;

extern int sii_scsistart();
extern int sii_reset();

extern struct scsi_devtab szp_rz_udt;
extern struct scsi_devtab szp_tz_udt;
extern struct scsi_devtab szp_cz_udt;
extern int szp_nrz;
extern int szp_ntz;
extern int szp_ncz;
extern int szp_nrx;
extern int rz_max_xfer;
extern int cz_max_xfer;
extern int tz_max_xfer;
extern int rzcomplete();
extern int tzcomplete();
extern int sz_cdb_length();

/**********************************************************************
 *
 * Name:	sii_probe
 *
 * Abstract:	The SII probe entry point routine from auto-configure
 *		code. Determine if the SII controller exists. Reset the
 *		SCSI bus. Size the number and type of targets on the
 *		SCSI bus. Set up the "sz_softc" structure and the 128K
 *		hardware buffer.
 *
 * Inputs:
 * reg		SCSI bus controller CSR address (not used).
 * cntlr	SCSI bus controller number (0 = bus A, 1 = bus B).
 *
 * Outputs:
 * sz_softc
 *
 *  sc_sysid		SCSI bus ID of initiator (CPU).
 *  *port_start()	SCSI command start routine - sii_scsistart().
 *  *port_reset()	SCSI bus reset - sii_reset().
 *  *device_comp()	SCSI device completion routine
 *  *sc_rambuff		Virtual address of 128KB hardware RAM buffer.
 *  sc_segcnt[]		Per target - 128 KB buffer slot size (max byte cnt).
 *  sc_dstp[]		Per target - disk default partition table pointer.
 *  sc_devtyp[]		Per target - device type (see scsireg.h).
 *  sc_alive[]		Per target - device present at this SCSI bus ID.
 *  sc_device[][]	Per target - product ID, vendor ID, rev in ascii.
 *  sc_SZ_bufmap[]	Per target - virtual address for buffer mapping.
 *  sc_szbufmap[]	Per target - PTEs from get_sys_ptes().
 *  sc_dboff[]		Per target - offset into 128 KB buffer.
 *  sc_devnam[][]	Per target - vendor & product ID in ascii.
 *  sc_revlvl[][]	Per target - revision level in ascii.
 *  sc_siisentsync[]	Per target - sent synchronous message flag.