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	4.6  (ULTRIX)        1/3/91";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1984,86,87,88,89 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.			*
 *									*
 *   This software is  derived	from  software	received  from	the	*
 *   University    of	California,   Berkeley,   and	from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is	subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   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	17-Aug-88
 *
 * VAX SCSI device driver (SII routines)
 *
 * Modification history:
 *
 * 11/21/90	Robin Miller
 *   o	Added support for 10-byte Read/Write CDB's.
 *   o  Removed '#ifdef FORMAT' conditionalization, since this special
 *	interface is always desired.
 *   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 problem was
 *	causing a "Panic: Protection Fault" when booting.
 *
 * 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-Aug_90 Bill Dallas
 *	Got rid of the -2 of the modsns len for disks. This was
 *	causing problems when we got rid of hard define for MODSNS_LEN
 *	which was 14 ( tapes). Caused problems on booting. In
 *	sii_startdma is where the changed was made.
 *
 * 05-Jul-90	Bill Dallas
 *	Added support for the new device option table
 *	Got rid of hard define
 *
 * 02-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 numbers).
 *
 * 13-Nov-89    Janet L. Schank
 *      During the message in phase, if an unsupported extended message
 *      is received, ATN is asserted before the last message byte
 *      is acknowledged.  Remove refrences to SII, replaced with nSII.
 *
 * 08-Oct-89	Fred Canter
 *	Removed error log #ifdef OLDWAY.
 *
 * 07-Oct-89	Fred Canter
 *	Save removable media bit from inquiry data in sz_softc.
 *
 * 17-Aug-89    Janet L. Schank
 *      sii_scsistart now uses sz_opcode as an index into the sz_timetable.
 *      This was done since pseudo-opcode values aren't in his table.  A
 *      check is also being done on the sz_opcode to make sure its in the
 *      table.
 *
 * 23-Jul-89	Fred Canter
 *	RX33 support.
 *
 * 16-Jul-89	Fred Canter
 *	Bug fix - mode sense byte was not set correctly.
 *	Allows mode sense to get disk geometry.
 *
 * 14-Jul-89	Fred Canter
 *	Merged Dynamic BBR and error log changes.
 *
 * 28-Jun-89	Fred Canter
 *	Convert error messages from printf to scsi_logerr().
 *
 * 23-Jun-89	Fred Canter
 *	Save status byte for current command for error log.
 *
 * 23-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.
 *
 * 20-Jun-89	Fred Canter
 *	Convert to scsi_devtab.
 *
 * 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.
 *
 * 06-Apr-89	Fred Canter
 *	Added b_comand to replace b_command for local command buffers.
 *	Use b_gid instead of b_resid to store command.
 *	No longer need to restore bp->b_command on error retry.
 *
 * 22-Feb-89	Alan Frechette
 *	A few minor probe changes. Fixed BUS DEVICE RESET handling.
 * 	Added the routine "sii_restart_target()" to restart driver
 *	activity for a particular target after a BUS DEVICE RESET 
 *	occurred on that particular target.
 *
 * 13-Feb-89	Alan Frechette
 *	Added in function headers for all subroutines. Allow an
 *	additional retry of the inquiry command in "sii_probe()"
 *	in the case that SZ_RET_ABORT is returned. Added an 
 *	additional check in "sii_intr()" when checking for DMA
 *	transfers ">8K".
 *
 * 12-Feb-89	Fred Canter
 *	Removed some comments which no longer apply.
 *
 * 11-Feb-89	Fred Canter
 *	Fixed yet another bug with 64KB transfers. Use blkcpy instead
 *	of bcopy (bcopy max byte count is 64KB -1 ) for copying
 *	data to and from the users' buffer.
 *
 *  5-Feb-89	Fred Canter
 *	Remove rz_max_xfer, cz_max_xfer, and tz_max_xfer.
 *
 * 27-Dec-88	Alan Frechette
 *	Made a change to break out of the (SZWAIT_UNTIL) loop in the
 *	routines "sii_recvdata()" and "sii_senddata()" during a DMA
 *	transfer if either the (SII_MIS) or (SII_DNE) bits are set.
 *
 *	Added debug printf's (PRINTD) to track timing of spin loops.
 *
 *	We no longer spin wait for phase changes in the routines
 *	"sii_scsistart()" and "sii_intr()". We now wait for the 
 *	interrupt to occur. We only spin wait for the "msgout" and 
 *	"command" phases. All other phases we wait for the interrupt.
 *
 *	Changed "scsi_completed" variable to be an array. It is now
 *	defined as "short scsi_completed[NDPS]".
 *
 * 19-Dec-88	Alan Frechette
 *	Added a small spinwait in "sii_state_change()" to wait for
 *	the (SII_CON) bit in the CSTAT REGISTER to be asserted if 
 *	the SII was expecting to be connected to a target. This is
 *	needed because the connect bit (SII_CON) can be asserted much 
 *	later than the reselect bit (SII_DST_ONBUS) on the SII.
 *
 *	Removed all the include files that were surrounded by the
 *	"#ifdef notdef" and "#endif notdef" construct.
 *
 *	Zero out ram buffer location in "sii_probe()" before issuing
 *	the inquiry command. This is needed to clear out any previous
 *	data in the ram buffer.
 *
 * 17-Dec-88	Fred Canter
 *	Added pseudo commands to resolve the conflict between
 *	SZ_UNLOAD and SZ_SSUNIT both being opcode 0x1b.
 *
 * 06-Dec-88	Alan Frechette
 *	Changed the select wait count in "sii_select_target()" to be
 *	2500 instead of 10000. Increased number of retries from 2 to 3.
 *	Fixed the sending of the DISCONNECT command in this routine
 *	also. The DISCONNECT command should only be sent if a selection 
 *	attempt failed and the selection in progress bit (SII_SIP) is
 *	set in the CSTAT REGISTER. The new select wait count is based
 *	on the Selection Timeout Delay in the scsi specification. The
 *	selection timeout value is 250 milliseconds.
 *
 *	Fixed probe to allow 64K transfers for the disk. Probe was
 *	allowing only (64K - 512) as the maximum disk transfer size.
 *
 * 01-Dec-88	Alan Frechette
 *	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.
 *
 *	Clear sent synchronous message flags "sc->sc_siisentsync[]"
 *	in "sii_reset()" when operating in scsi polled mode during
 *	boot up. If we get a reset we must clear these flags or else
 *	the system will not come up.
 *
 *	Reworked the debugging for the SII. Improved it considerably.
 *
 * 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. Made some more 
 *	performance improvements to the SII. I now pass "targid" to 
 *	every subroutine I call and got rid of the useless subroutine 
 *	"sii_getactive_target()". 
 *
 *	Add in support for non-DEC disks. This is done in the probe
 *	routine and the non-DEC disks are designated by "RZxx". Also
 *	removed "#define SZDEBUG" from this file.
 *
 *	Changed the spin loops for PHASE CHANGES. If a PHASE CHANGE 
 *	does not occur within the spin loop time period then the code
 *	will return and wait for the PHASE CHANGE interrupt from the SII. 
 *
 *	Added scsi command timeout logic to the SII. The routine 
 *	"sii_timer()" handles the command timeout logic. The SII
 *	uses the command timeout table "sz_timetable[]" defined
 *	in the file "scsi.c".
 *
 *	Made a change to handle devices that do not support scsi
 *	Extended Messages in "sii_msgout()". 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.
 *
 *	Implemented the Bus Device Reset message to reset only a
 *	particular SCSI device and not the entire SCSI bus. Also
 *	implemented the Abort message to abort the current command
 *	due to an error.
 *
 *	Fixed the routine "sii_clear_discon_io_requests()" to not
 *	return an IO error on the disconnected IO request after a 
 *	reset occurred on the SCSI bus.
 *
 *	Fixed the entire "reset" handling throughout this driver.
 *
 * 08-Sep-88	Alan Frechette
 *	Fixed the handling of spurious interrupts on the SII. The
 *	interrupt routine will ignore all spurious interrupts from 
 *	the SII and will simply return. 
 *
 *	The following fixes were made to support the CDROM device:
 *	1: Fixed the handling of the Synchronous Data Transfer Request 
 *	   message with the CDROM device. The CDROM device would switch
 *	   phase before it would recieve the last byte of this message. 
 *	
 *	2: Ignore the second disconnect if we get back-to-back 
 *	   disconnects from the CDROM device. 
 *
 *	3: Rewrote 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). Corrected 
 *	   some of the logic in this routine.
 *
 * 01-Sep-88	Alan Frechette
 *	Save the value of the DMA Length Of Transfer Count register
 *	in "sii_msgin". Since the SII now uses DMA for all information
 *	transfers we must save the this value in case the message
 *	is a SAVE DATA POINTER message. Otherwise we will lose the
 *	true state of the DMA for that target and how much data was 
 *	actually transfered.
 *
 *	Made a fix to "sii_senddata" when using programmed io. Added
 *	the setting of the "attn" variable when setting the Command
 *	register in the SII. 
 *
 * 23-Aug-88	Alan Frechette
 *	Fixed the GENERIC kernel boot problem for SII systems.
 *	The GENERIC kernel now boots off an SII based 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.
 *
 ***********************************************************************/

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

#ifdef SZDEBUG
/*********************************************************************
 *	      NOTE ON HOW DEBUGGING WORKS FOR SII DRIVER
 *
 * The scsi debug variable "siidebug" controls the level of debugging
 * and is defined as follows:
 *
 * bit 0: prints out only scsi bus phase/state values.	(siidebug=0x1)
 * bit 1: prints out only the expansion of commands.  	(siidebug=0x2)
 * bit 2: prints out only errors encountered.	       	(siidebug=0x4)
 * bit 3: prints out only code flow through routines. 	(siidebug=0x8)
 * bit 4: prints out only spurious interrupts. 		(siidebug=0x10)
 * bit 5: prints out only timer values of spin loops. 	(siidebug=0x20)
 *
 * The scsi target variable "siitarget" controls the debugging of a
 * specific target only. 
 *
 * bit 0: prints out only debugging for target 0	(siitarget=0x1)
 * bit 1: prints out only debugging for target 1	(siitarget=0x2)
 * bit 2: prints out only debugging for target 2	(siitarget=0x4)
 * bit 3: prints out only debugging for target 3	(siitarget=0x8)
 * bit 4: prints out only debugging for target 4	(siitarget=0x10)
 * bit 5: prints out only debugging for target 5	(siitarget=0x20)
 * bit 6: prints out only debugging for target 6	(siitarget=0x40)
 * bit 7: prints out only debugging for target 7	(siitarget=0x80)
 * all  : prints out debugging for all targets		(siitarget=-1)
 *
 *
 * EXAMPLE: Debug (target 3) with bitmask (bit0|bit1|bit2)
 *
 * 		adb -w -k /vmunix /dev/mem
 * 		siitarget/W 8		(Set to target 3)
 * 		siidebug/W 7		(Set debug bitmask to 7)
 * 		$q
 *
 ********************************************************************/
int siidebug = 0;
int siitarget = 0;
#define PRINTD(T,F,X) {						\
    if(siidebug & F) {						\
	if((siitarget & (1<<T)) || siitarget == -1 || T == -1)	\
	    cprintf X;						\
    }								\
}
#endif SZDEBUG


/*
 * Number of seconds to wait for SCSI devices
 * to come ready enough to respond to inquiry
 * after a 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;

int	sii_wait_after_inquiry = 1000;

/*
 * More external declarations for the SII.
 */
extern char cvqmsi[] [512*NBPG];/* The SII registers in IO SPACE */
extern char cvqmsirb[];		/* The 128K RAM buffer for the SII */
extern char szbufmap[];		/* Holds PTE's from get_sys_ptes() */
extern short sz_timetable[];	/* Command timeout table for SII chip */
extern int szp_nrz;		/* Number of RZ disks found */
extern int szp_ntz;		/* Number of TZ tapes found */
extern int szp_ncz;		/* Number of CDROM optical disks found */
extern int szp_nrx;		/* Number of CDROM optical disks found */
extern struct scsi_devtab szp_rz_udt;
extern struct scsi_devtab szp_tz_udt;
extern struct scsi_devtab szp_cz_udt;
extern int sii_scsistart();	/* SII scsi start routine */
extern int sii_reset();		/* SII scsi reset routine */
int sii_restart_target();	/* SII scsi restart target routine */
int sz_strncmp();
int sz_strcmp();
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).
 *