stc.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static char *sccsid = "@(#)stc.c	4.1	ULTRIX	7/2/90";
#endif lint

/************************************************************************
 *									*
 *		Copyright (c) 1984, 1986, 1987, 1988, 1989 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.	*
 *									*
 ************************************************************************/

/************************************************************************
 * stc.c 	02-Mar-89
 *
 * Modification history
 *
 * TZK50 Tape Driver
 *
 * 02-Dec-89	Fred Canter
 *	Bug fix; mprintf to error log printed address of sense data
 *	bytes instead of the data in the sense data bytes.
 *	Bug fix; restore issues a MTNOCACHE ioctl which causes a hardware
 *	error on the TZK50. This prevented TK50 installtaions to MV2000
 *	and VS2000 systems.
 *
 * 17-May-89	Fred Canter
 *	Yet another bug fix. Back/forward space thru a file mark should
 *	fail but wasn't.
 *
 * 13-May-89	Fred Canter
 *	Fixed yet another bug uncovered by the V3.1 installation. There
 *	were many errors in the DEV_TPMARK flag handling. Code changes
 *	identified with "#ifdef TM_NO_FIX". To include the fix, don't
 *	define TM_NO_FIX.
 *
 * 10-May-89	Fred Canter
 *	Fix to last bug fix. Caused driver to return error on filemark
 *	read instead of returning the users' byte count.
 *
 * 25-Apr-89	Fred Canter
 *	Cleared all flags in the open routine. This fixed a bug which
 *	caused the driver to fail all reads after any fatal error, until
 *	the system was rebooted.
 *
 *	Changed printf to printd1 for the "Didn't space back over second
 *	filemark" debug message.
 *
 * 24-Apr-89	Fred Canter
 *	Rev 45 of the TZK50 firmware caused this driver to fail, because
 *	it did not expect a save data pointer message with no data
 *	remaining to be transferred (i.e., DMA count register = 0).
 *
 * 02-Mar-89	John A. Gallant
 *	In st_start(), correctly initialized the um pointer.
 *
 * 28-Sep-88	Fred Canter
 *	Clean up comments.
 *
 * 01-Sep-88	darrell
 *	ST_W_DMA: now saves a copy of sc_stflags which it restore, as
 *	the call to st_scsistart() clears sc_stflags.  Also corrected
 *	the check in ST_SP_CONT: that determines if the REQUEST SENSE
 *	succeeded.  This fixes a P1 bug that was elevated to a CLD
 *	(SPR 4st-00571)
 *
 * 06-Jun-88	Fred Canter
 *	Changes to allow this driver to use PVAX extended data buffer
 *	I/O mode.
 *
 * 15-Feb-88	Fred Canter
 *	Changes for VAX420 (CVAXstar/PVAX) support.
 *
 * 12-Jan-88	darrell
 *	Rewrote st_timer().  I had forgotten about the fact that a
 *	space command could take up to approximately 40 minutes to 
 *	complete.  The timer was set to go off every 3 minutes and 
 *	if a command had not completed as of the second time timeout
 *	the drive was assumed to be dead.  Each command is now looked
 *	up in a table and timed separately.
 *
 * 15-Sep-87	darrell
 *	Copied most if stintr() into another routine st_scsistart() which
 *	is used to start the scsi transfer.  stintr used to be called by
 *	st_start() to start the scsi transfer which was clearly not how
 *	an interrupt routine is supposed to work, and it also made
 *	returning from stintr() and st_start() quite complex.  As a result
 *	of these latest changes, st_start calls st_scsistart() to start
 *	the transfer, and stintr() is only called from interrupt -- which
 *	is much cleaner, and the "right" thing to do.  At the same time
 *	the sc_stflags field in the ST_R_DMA: case is restored after the
 *	Request Sense Command -- which fixes a panic which was happening
 *	in vs_bufctl.
 *
 * 20-Aug-87	darrell
 *	Added a timeout routine (st_timer) to timeout commands and reset 
 *	the controller.  A request diagnostic results command is now send
 *	to read the controller firmware and refuse to be opened if the
 *	firmware rev is below REV 34.  The first command sent to the drive
 *	now is a Receive Diagnostic Results command.  This should always
 *	return success if the drive is there and working, so we no longer 
 *	need to wait for three minutes with a Test Unit Ready of "not ready"
 *	in order to tell if the tape is there.
 *
 * 23-Apr-87	darrell
 *	Changed the calls to vs_bufctl to pass a pointer to a structure
 *	that contains a pointer to the function	that vs_bufctl is to call.
 *	This is the first step of cleaning up some of this code, and making
 *	it more maintainable.
 *
 * 15-Mar-87	darrell
 *	Removed the code that does a bus reset.  The bus reset was being
 *	done on all error conditions.  Now a bus reset is never done.
 *
 * 03-Mar-87	darrell
 *	Added multi-volume support.  Fixed various small bugs.  Increased
 *	the default number of fills to seven (7).  If the drive exists, but
 *	the tape is not loaded, and the open routine is called with FNDELAY,
 *	the driver now waits to make sure that there is not an outstanding
 *	rewind.
 *
 * 27-Jan-87	darrell
 *	Added support for the change in V32 of the TZK50 microcode that
 *	allows the reselect timeout (TZK50 timing out the host) to be
 *	disabled.  A change was also made to catch and return an iodone
 *	on buffers that were queued as a result of nbuffio, after a
 *	hard error was detected.  Also OR'ed the density bits into the
 *	category_stat field in the DEVIOGET case of stioctl -- so now
 *	dump can calculate the correct length of tape needed.
 *
 * 15-Jan-87	darrell
 *	Rewrote about half of this driver to support
 *	disconnects/reselects, make the tape stream, and
 * 	reduce the adverse performance impact this driver
 *	had on the system.  Seems to work well.  EOT is
 *	still not tested.
 *
 * 23-Oct-86	darrell
 *	Fixed a FNDELAY problem so finder now works.
 *
 * 26-Sep-86	darrell
 *	Cleaned up error message printouts, and fixed a problem where
 *	opening the device FNDELAY allowed the first command after
 *	changing a tape to fail.
 *
 * 26-Sep-86	darrell
 *	Removed a debug printf I had left in my last delta.
 *
 * 26-Sep-86	darrell
 *	Fixed a problem queueing multiple requests so that nbuf
 *	I/O will work.  Also enabled buffered writing.
 *
 * 12-Sep-86	darrell
 *	Fixed remaining ioctl's, put in the devioctl code to
 *	to work with the utilities using nbufio.  bp->b_resid
 *	is now returned correctly.  Fixed many other little bugs.
 *
 * 04-Sep-86	darrell
 *	Made ioctls work - all except MTIOCGET:, put in code to
 *	handle EOM, EOT, and other tape end contition, and did a
 *	lot of cleanup in removing old unused code, and comments,
 *	and changed ST_SP_COMPL: DATAI: to only read as many
 *	characters as are expected in program I/O -- as the STATUS
 *	byte was getting sucked in.
 *
 *  4-Sep-86    darrell (Darrell Dunnuck)
 *	First semi-working driver.
 *
 * 26-Aug-86	rsp (Ricky Palmer)
 *	Cleaned up devioctl code to (1) zero out devget structure
 *	upon entry and (2) use strlen instead of fixed storage
 *	for bcopy's.
 *
 *  5-Aug-86	darrell
 *	First pass of real driver (compiles but not debugged).
 *
 * 12-Jun-86	darrell
 *	started with ht.c, and made it into this file.
 *
 */

/***********************************************************************
 * TODO:
 *
 *	1. This driver needs to support record sizes greater that 16k.
 *	   The maximum size supported by the TZK50 is 64k.  This driver 
 *	   should be changed to support record sizes up to 64k.
 ***********************************************************************
 */
  

/*  */
#if NST > 0 || defined(BINARY)

#include "../data/stc_data.c"

extern int cvs_exmode_on;
u_char inicmd_tmp;  /* keep this around since we can't |=  the scs_inicmd reg */
int st_from_open;   /* used to tell when the command was initiated from stopen*/
int st_retries = 0; /* retry counter					      */
int st_max_numof_fills = ST_DEFAULT_FILLS; /* Maximum number of fills to write*/
					   /* in order to try to keep the tape*/
					   /* drive streaming.		      */

extern struct vsbuf vsbuf;
struct vsdev vstapedev = { VS_ST, 0, 0 };
int	stprobe(), stslave(), stattach(), stintr(), st_start(),	sterror(), st_timer(), st_scsistart();

u_short	ststd[] = { 0 };

struct	uba_driver stcdriver = { stprobe, stslave, stattach, st_start,
				ststd, "st", stdinfo, "stc", stminfo,
				0 };

int wakeup();
extern int hz;
extern struct nexus nexus[];
struct	stspace	ST_bufmap[];

extern	int	cpu;
extern	int	cpu_subtype;

#define ST_TIMERRATE	30	/* how often the timer goes off		      */

int	unit_attn = 1;	/* An indication that the tape was removed */

/*
 * The following table is the timeout value for each command assuming that
 * the timer is set to go off every 30 seconds.
 */
char st_timetable[48] = {	 2,	/* ST_TUR		0x00	*/
				 6,	/* ST_REWIND		0x01	*/
				 0,	/* unused		0x02	*/
				 2,	/* ST_RQSNS		0x03	*/
				 0,	/* unused		0x04	*/
				 0,	/* ST_RBL		0x05	*/
				 0,	/* unused		0x06	*/
				 0,	/* unused		0x07	*/
				 8,	/* ST_READ		0x08	*/
				 0,	/* unused		0x09	*/
				 8,	/* ST_WRITE		0x0a	*/
				 2,	/* ST_TRKSEL		0x0b	*/
				 0,	/* unused		0x0c	*/
				 0,	/* unused		0x0d	*/
				 0,	/* unused		0x0e	*/
				 0,	/* unused		0x0f	*/
				 2,	/* ST_WFM		0x10	*/
				90,	/* ST_SPACE		0x11	*/
				 2,	/* ST_INQ		0x12	*/
				 0,	/* ST_VFY		0x13	*/
				 0,	/* ST_RBD		0x14	*/
				 2,	/* ST_MODSEL		0x15	*/
				 0,	/* ST_RESUNIT		0x16	*/
				 0,	/* ST_RELUNIT		0x17	*/
				 0,	/* unused		0x18	*/
				 0,	/* ST_ERASE		0x19	*/
				 2,	/* ST_MODSNS		0x1a	*/
				 6,	/* ST_LOAD/ST_UNLOAD	0x1b	*/
				 6,	/* ST_RCVDIAG		0x1c	*/
				 0,	/* ST_SNDDIAG		0x1d	*/
				90,	/* ST_FSPACER		0x1e	*/
				90,	/* ST_FSPACEF		0x1f	*/
				 0,	/* unused		0x20	*/
				 0,	/* unused		0x21	*/
				 0,	/* unused		0x22	*/
				 0,	/* unused		0x23	*/
				 0,	/* unused		0x24	*/
				 0,	/* unused		0x25	*/
				 0,	/* unused		0x26	*/
				 0,	/* unused		0x27	*/
				 0,	/* unused		0x28	*/
				 0,	/* unused		0x29	*/
				 0,	/* unused		0x2a	*/
				 0,	/* unused		0x2b	*/
				 2,	/* ST_P_CACHE		0x2c	*/
				 2,	/* ST_P_NOCACHE		0x2d	*/
				90,	/* ST_BSPACER		0x2e	*/
				90	/* ST_BSPACEF		0x2f	*/
};

/* STDEBUG intentionally left defined */
#define STDEBUG
#ifdef STDEBUG
#define ST_TRACK_SIZE     100	/* size of the tracking buffer */
#define ST_CMDTRACK_SIZE  600	/* size of the command tracking buffer */
char sttrack[ST_TRACK_SIZE];
char stcmdtrack[ST_CMDTRACK_SIZE];
int st_cmdindex = ((ST_CMDTRACK_SIZE) - 1);
int st_index = ST_TRACK_SIZE - 1;
/*
 * ST_TRACK - a macro that writes into the ST_TRACK_SIZE
 * array that is used as a trail of what this driver has
 * done.  The data is written into the array starting from
 * the highest address down to the lowest address to make
 * it easier to trace backwards using adb.
 *
 */
#define ST_TRACK(a) if(st_index < 0 )				\
			st_index = (ST_TRACK_SIZE - 1);		\
		    sttrack[st_index--] = a
/*
 * ST_CMDTRACK - a macro that writes into an array the command
 * that was sent to the drive -- to be used as a trail of 
 * what this driver has done. The data is written into the array 
 * starting from the highest address down to the lowest address
 * to make it easier to trace backwards using adb.
 */
#define ST_CMDTRACK(a) if(st_cmdindex < 0 )				\
			st_cmdindex = ((ST_CMDTRACK_SIZE) - 1);	\
		    stcmdtrack[st_cmdindex--] = a

int stdebug = 0;
#define printd if(stdebug)printf
#define printd1 if (stdebug > 1) printf
#define printd2 if (stdebug > 2) printf
#define printd3 if (stdebug > 3) printf
#define printd4 if (stdebug > 4) printf
#define printd5 if (stdebug > 5) printf
#define printd6 if (stdebug > 6) printf
int st_direct_track_mode = 0;	/* for testing multivolume dump */
u_char st_prev_cmd;	/* keeps track of the previous command sent to drive */

/*
 * Trace Tables
 */
char	*trace_xstate [] = {
	"ST_NEXT",
	"ST_SP_START",
	"ST_SP_CONT",
	"ST_RW_START",
	"ST_R_STDMA",
	"ST_W_STDMA",
	"ST_R_DMA",
	"ST_W_DMA",
	"ST_R_COPY",
	"ST_R_DMACONT",
	"ST_W_DMACONT",
	"ST_ERR"
};

char	*trace_fstate [] = {
	"ST_SP_ARB",
	"ST_SP_SEL",
	"ST_CMD_PHA",
	"ST_DATAO_PHA",
	"ST_DATAI_PHA",
	"ST_STATUS_PHA",
	"ST_MESSI_PHA",
	"ST_MESSO_PHA",
	"ST_RELBUS",
	"ST_ABORT"
};

char	*trace_event [] = {
	"ST_CONT",
	"ST_BEGIN",
	"ST_DMA_DONE",
	"ST_PAR_ERR",
	"ST_PHA_MIS",
	"ST_RESET",
	"ST_CMD",
	"ST_DMA",
	"ST_ABRT",
	"ST_ERROR",
	"ST_TIMEOUT",
	"ST_FREEB"
};
#endif STDEBUG

/*  */
stprobe(reg, cntlr)
	int cntlr;
	caddr_t reg;
{
	register struct nb1_regs *staddr = (struct nb1_regs *)qmem;
	register struct nb_regs *stiaddr = (struct nb_regs *)nexus;

#ifdef STDEBUG
	printd6("stprobe: probing TZK50\n");
#endif STDEBUG

	/*
	 * This driver only runs on VAXstar/Teammate.
	 * It cannot be used with CVAXstar/PVAX.
	 */
	if (cpu != VAXSTAR)
		return(0);
	stiaddr->nb_int_reqclr = SCS_INT_TAPE;	/* clear SCSI in INT_REQ reg */
	stiaddr->nb_int_msk |= SCS_INT_TAPE;	/* enable SCSI interrupts */

	/* the reset of the SCSI bus may cause an interrupt */
	staddr->scs_inicmd = SCS_INI_RST;	/* reset the SCSI bus */
	DELAY(100000);

	/* clear RST */
	staddr->scs_inicmd = 0;

	/* make the controller interrupt */
	/* may not need this stuff, the reset may cause an interrupt */
	if((stiaddr->nb_int_reqclr&SCS_INT_TAPE) == 0) {	/* didn't cause intr */
		staddr->scs_selena = SCS_ID0;
		staddr->scs_outdata = (SCS_ID0 | SCS_ID1);
		staddr->scs_inicmd = (SCS_INI_SEL | SCS_INI_ENOUT);
		DELAY(100000);	/* may not need this */
		staddr->scs_inicmd = 0;
		staddr->scs_selena = 0;
	}
	stiaddr->nb_int_reqclr = SCS_INT_TAPE;	/* clear SCSI in INT_REQ reg */

#ifdef STDEBUG
	if (cvec && cvec == 0x200)	/* check for interrupt */
		printd6("stprobe: controller didn't interrupt\n");
	else
		printd6("stprobe: controller found at vector %o\n", cvec);
#endif STDEBUG
	return(1);

	/*
	 * Determine if the drive exists, and is a TK50.
	 * We can get away with using a dev of zero in the 
	 * stcommand because it is not checked anywhere in
	 * this driver.
	 */
}

/*  */
stattach(ui)
	register struct uba_device *ui;
{
	register struct uba_ctlr *um;

	ui->ui_flags = 0;
	/*
	 * Link the drive buffer to the controller queue and
	 * leave it there since there is only one drive.  We'll
	 * check for outstanding requests queued for the drive.
	 */
	um = ui->ui_mi;
	um->um_tab.b_actf = &stutab[0];
	um->um_tab.b_actl = &stutab[0];
	um->um_tab.b_actf->b_actf = NULL;
}

/*  */
stslave(ui)
	register struct uba_device *ui;
{
	register struct st_softc *sc;
	register int s = spl5();

	sc = &st_softc[0];
	bcopy(DEV_TK50, sc->sc_device, strlen(DEV_TK50));
	splx(s);
	if (ui->ui_slave)
		return(0);
	return(1);
}

/*  */
stopen(dev, flag)
	register dev_t dev;
	register int flag;
{
	register struct uba_device *ui;
	register struct st_softc *sc;
	int unit = UNIT(dev);
	int retry = 0;
	int retval;

#ifdef STDEBUG
	ST_TRACK('o');
#endif STDEBUG
	if (unit >= nNST || (sc = &st_softc[unit])->sc_openf ||
	    (ui = stdinfo[unit]) == 0 || ui->ui_alive == 0) {
		return (ENXIO);
	}
	/*
	 * This is a strange use of the FNDELAY flag.  It
	 * is here to allow the installation finder program
	 * to open the device when the tape cartridge is not
	 * inserted.  The installation finder program needs
	 * to do an ioctl, so open must succeed whether or