/*	$OpenBSD: uha.c,v 1.18 2010/06/26 23:24:44 guenther Exp $	*/
/*	$NetBSD: uha.c,v 1.3 1996/10/13 01:37:29 christos Exp $	*/

#undef UHADEBUG
#ifdef DDB
#define	integrate
#else
#define	integrate	static inline
#endif

/*
 * Copyright (c) 1994, 1996 Charles M. Hannum.  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 Charles M. Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/*
 * Ported for use with the UltraStor 14f by Gary Close (gclose@wvnvms.wvnet.edu)
 * Slight fixes to timeouts to run with the 34F
 * Thanks to Julian Elischer for advice and help with this port.
 *
 * Originally written by Julian Elischer (julian@tfs.com)
 * for TRW Financial Systems for use under the MACH(2.5) operating system.
 *
 * TRW Financial Systems, in accordance with their agreement with Carnegie
 * Mellon University, makes this software available to CMU to distribute
 * or use in any manner that they see fit as long as this message is kept with
 * the software. For this reason TFS also grants any other persons or
 * organisations permission to use or modify this software.
 *
 * TFS supplies this software to be publicly redistributed
 * on the understanding that TFS is not responsible for the correct
 * functioning of this software in any circumstances.
 *
 * commenced: Sun Sep 27 18:14:01 PDT 1992
 * slight mod to make work with 34F as well: Wed Jun  2 18:05:48 WST 1993
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <uvm/uvm_extern.h>

#include <machine/bus.h>
#include <machine/intr.h>

#include <scsi/scsi_all.h>
#include <scsi/scsiconf.h>

#include <dev/ic/uhareg.h>
#include <dev/ic/uhavar.h>

#define KVTOPHYS(x)	vtophys((vaddr_t)x)

integrate void uha_reset_mscp(struct uha_softc *, struct uha_mscp *);
void uha_free_mscp(struct uha_softc *, struct uha_mscp *);
integrate void uha_init_mscp(struct uha_softc *, struct uha_mscp *);
struct uha_mscp *uha_get_mscp(struct uha_softc *, int);
void uhaminphys(struct buf *, struct scsi_link *);
void uha_scsi_cmd(struct scsi_xfer *);

struct scsi_adapter uha_switch = {
	uha_scsi_cmd,
	uhaminphys,
	0,
	0,
};

/* the below structure is so we have a default dev struct for out link struct */
struct scsi_device uha_dev = {
	NULL,			/* Use default error handler */
	NULL,			/* have a queue, served by this */
	NULL,			/* have no async handler */
	NULL,			/* Use default 'done' routine */
};

struct cfdriver uha_cd = {
	NULL, "uha", DV_DULL
};

#define	UHA_ABORT_TIMEOUT	2000	/* time to wait for abort (mSec) */

#ifdef __OpenBSD__
int	uhaprint(void *, const char *);

int
uhaprint(aux, name)
	void *aux;
	const char *name;
{

	if (name != NULL)
		printf("%s: scsibus ", name);
	return UNCONF;
}
#endif

/*
 * Attach all the sub-devices we can find
 */
void
uha_attach(sc)
	struct uha_softc *sc;
{
	struct scsibus_attach_args saa;

	(sc->init)(sc);
	TAILQ_INIT(&sc->sc_free_mscp);

	/*
	 * fill in the prototype scsi_link.
	 */
	sc->sc_link.adapter_softc = sc;
	sc->sc_link.adapter_target = sc->sc_scsi_dev;
	sc->sc_link.adapter = &uha_switch;
	sc->sc_link.device = &uha_dev;
	sc->sc_link.openings = 2;

	bzero(&saa, sizeof(saa));
	saa.saa_sc_link = &sc->sc_link;

	/*
	 * ask the adapter what subunits are present
	 */
	config_found(&sc->sc_dev, &saa, uhaprint);
}

integrate void
uha_reset_mscp(sc, mscp)
	struct uha_softc *sc;
	struct uha_mscp *mscp;
{

	mscp->flags = 0;
}

/*
 * A mscp (and hence a mbx-out) is put onto the free list.
 */
void
uha_free_mscp(sc, mscp)
	struct uha_softc *sc;
	struct uha_mscp *mscp;
{
	int s;

	s = splbio();

	uha_reset_mscp(sc, mscp);
	TAILQ_INSERT_HEAD(&sc->sc_free_mscp, mscp, chain);

	/*
	 * If there were none, wake anybody waiting for one to come free,
	 * starting with queued entries.
	 */
	if (TAILQ_NEXT(mscp, chain) == NULL)
		wakeup(&sc->sc_free_mscp);

	splx(s);
}

integrate void
uha_init_mscp(sc, mscp)
	struct uha_softc *sc;
	struct uha_mscp *mscp;
{
	int hashnum;

	bzero(mscp, sizeof(struct uha_mscp));
	/*
	 * put in the phystokv hash table
	 * Never gets taken out.
	 */
	mscp->hashkey = KVTOPHYS(mscp);
	hashnum = MSCP_HASH(mscp->hashkey);
	mscp->nexthash = sc->sc_mscphash[hashnum];
	sc->sc_mscphash[hashnum] = mscp;
	uha_reset_mscp(sc, mscp);
}

/*
 * Get a free mscp
 *
 * If there are none, see if we can allocate a new one.  If so, put it in the
 * hash table too otherwise either return an error or sleep.
 */
struct uha_mscp *
uha_get_mscp(sc, flags)
	struct uha_softc *sc;
	int flags;
{
	struct uha_mscp *mscp;
	int s;

	s = splbio();

	/*
	 * If we can and have to, sleep waiting for one to come free
	 * but only if we can't allocate a new one
	 */
	for (;;) {
		mscp = TAILQ_FIRST(&sc->sc_free_mscp);
		if (mscp) {
			TAILQ_REMOVE(&sc->sc_free_mscp, mscp, chain);
			break;
		}
		if (sc->sc_nummscps < UHA_MSCP_MAX) {
			mscp = (struct uha_mscp *) malloc(sizeof(struct uha_mscp),
			    M_TEMP, M_NOWAIT);
			if (!mscp) {
				printf("%s: can't malloc mscp\n",
				    sc->sc_dev.dv_xname);
				goto out;
			}
			uha_init_mscp(sc, mscp);
			sc->sc_nummscps++;
			break;
		}
		if ((flags & SCSI_NOSLEEP) != 0)
			goto out;
		tsleep(&sc->sc_free_mscp, PRIBIO, "uhamsc", 0);
	}

	mscp->flags |= MSCP_ALLOC;

out:
	splx(s);
	return (mscp);
}

/*
 * given a physical address, find the mscp that it corresponds to.
 */
struct uha_mscp *
uha_mscp_phys_kv(sc, mscp_phys)
	struct uha_softc *sc;
	u_long mscp_phys;
{
	int hashnum = MSCP_HASH(mscp_phys);
	struct uha_mscp *mscp = sc->sc_mscphash[hashnum];

	while (mscp) {
		if (mscp->hashkey == mscp_phys)
			break;
		mscp = mscp->nexthash;
	}
	return (mscp);
}

/*
 * We have a mscp which has been processed by the adaptor, now we look to see
 * how the operation went.
 */
void
uha_done(sc, mscp)
	struct uha_softc *sc;
	struct uha_mscp *mscp;
{
	struct scsi_sense_data *s1, *s2;
	struct scsi_xfer *xs = mscp->xs;

	SC_DEBUG(xs->sc_link, SDEV_DB2, ("uha_done\n"));
	/*
	 * Otherwise, put the results of the operation
	 * into the xfer and call whoever started it
	 */
	if ((mscp->flags & MSCP_ALLOC) == 0) {
		panic("%s: exiting ccb not allocated!\n", sc->sc_dev.dv_xname);
		return;
	}
	if (xs->error == XS_NOERROR) {
		if (mscp->host_stat != UHA_NO_ERR) {
			switch (mscp->host_stat) {
			case UHA_SBUS_TIMEOUT:		/* No response */
				xs->error = XS_SELTIMEOUT;
				break;
			default:	/* Other scsi protocol messes */
				printf("%s: host_stat %x\n",
				    sc->sc_dev.dv_xname, mscp->host_stat);
				xs->error = XS_DRIVER_STUFFUP;
			}
		} else if (mscp->target_stat != SCSI_OK) {
			switch (mscp->target_stat) {
			case SCSI_CHECK:
				s1 = &mscp->mscp_sense;
				s2 = &xs->sense;
				*s2 = *s1;
				xs->error = XS_SENSE;
				break;
			case SCSI_BUSY:
				xs->error = XS_BUSY;
				break;
			default:
				printf("%s: target_stat %x\n",
				    sc->sc_dev.dv_xname, mscp->target_stat);
				xs->error = XS_DRIVER_STUFFUP;
			}
		} else
			xs->resid = 0;
	}
	uha_free_mscp(sc, mscp);
	scsi_done(xs);
}

void
uhaminphys(struct buf *bp, struct scsi_link *sl)
{
	if (bp->b_bcount > ((UHA_NSEG - 1) << PGSHIFT))
		bp->b_bcount = ((UHA_NSEG - 1) << PGSHIFT);
	minphys(bp);
}

/*
 * start a scsi operation given the command and the data address.  Also
 * needs the unit, target and lu.
 */
void
uha_scsi_cmd(xs)
	struct scsi_xfer *xs;
{
	struct scsi_link *sc_link = xs->sc_link;
	struct uha_softc *sc = sc_link->adapter_softc;
	struct uha_mscp *mscp;
	struct uha_dma_seg *sg;
	int seg;		/* scatter gather seg being worked on */
	u_long thiskv, thisphys, nextphys;
	int bytes_this_seg, bytes_this_page, datalen, flags;
	int s;

	SC_DEBUG(sc_link, SDEV_DB2, ("uha_scsi_cmd\n"));
	/*
	 * get a mscp (mbox-out) to use. If the transfer
	 * is from a buf (possibly from interrupt time)
	 * then we can't allow it to sleep
	 */
	flags = xs->flags;
	if ((mscp = uha_get_mscp(sc, flags)) == NULL) {
		xs->error = XS_NO_CCB;
		scsi_done(xs);
		return;
	}
	mscp->xs = xs;
	mscp->timeout = xs->timeout;
	timeout_set(&xs->stimeout, uha_timeout, xs);

	/*
	 * Put all the arguments for the xfer in the mscp
	 */
	if (flags & SCSI_RESET) {
		mscp->opcode = UHA_SDR;
		mscp->ca = 0x01;
	} else {
		mscp->opcode = UHA_TSP;
		/* XXX Not for tapes. */
		mscp->ca = 0x01;
		bcopy(xs->cmd, &mscp->scsi_cmd, mscp->scsi_cmd_length);
	}
	mscp->xdir = UHA_SDET;
	mscp->dcn = 0x00;
	mscp->chan = 0x00;
	mscp->target = sc_link->target;
	mscp->lun = sc_link->lun;
	mscp->scsi_cmd_length = xs->cmdlen;
	mscp->sense_ptr = KVTOPHYS(&mscp->mscp_sense);
	mscp->req_sense_length = sizeof(mscp->mscp_sense);
	mscp->host_stat = 0x00;
	mscp->target_stat = 0x00;

	if (xs->datalen) {
		sg = mscp->uha_dma;
		seg = 0;

		/*
		 * Set up the scatter gather block
		 */
		SC_DEBUG(sc_link, SDEV_DB4,
		    ("%d @0x%x:- ", xs->datalen, xs->data));
		datalen = xs->datalen;
		thiskv = (int) xs->data;
		thisphys = KVTOPHYS(thiskv);

		while (datalen && seg < UHA_NSEG) {
			bytes_this_seg = 0;

			/* put in the base address */
			sg->seg_addr = thisphys;

			SC_DEBUGN(sc_link, SDEV_DB4, ("0x%x", thisphys));

			/* do it at least once */
			nextphys = thisphys;
			while (datalen && thisphys == nextphys) {
				/*
				 * This page is contiguous (physically)
				 * with the last, just extend the
				 * length
				 */
				/* how far to the end of the page */
				nextphys = (thisphys & ~PGOFSET) + NBPG;
				bytes_this_page = nextphys - thisphys;
				/**** or the data ****/
				bytes_this_page = min(bytes_this_page,
						      datalen);
				bytes_this_seg += bytes_this_page;
				datalen -= bytes_this_page;

				/* get more ready for the next page */
				thiskv = (thiskv & ~PGOFSET) + NBPG;
				if (datalen)
					thisphys = KVTOPHYS(thiskv);
			}
			/*
			 * next page isn't contiguous, finish the seg
			 */
			SC_DEBUGN(sc_link, SDEV_DB4,
			    ("(0x%x)", bytes_this_seg));
			sg->seg_len = bytes_this_seg;
			sg++;
			seg++;
		}

		SC_DEBUGN(sc_link, SDEV_DB4, ("\n"));
		if (datalen) {
			/*
			 * there's still data, must have run out of segs!
			 */
			printf("%s: uha_scsi_cmd, more than %d dma segs\n",
			    sc->sc_dev.dv_xname, UHA_NSEG);
			goto bad;
		}
		mscp->data_addr = KVTOPHYS(mscp->uha_dma);
		mscp->data_length = xs->datalen;
		mscp->sgth = 0x01;
		mscp->sg_num = seg;
	} else {		/* No data xfer, use non S/G values */
		mscp->data_addr = (physaddr)0;
		mscp->data_length = 0;
		mscp->sgth = 0x00;
		mscp->sg_num = 0;
	}
	mscp->link_id = 0;
	mscp->link_addr = (physaddr)0;

	s = splbio();
	(sc->start_mbox)(sc, mscp);
	splx(s);

	/*
	 * Usually return SUCCESSFULLY QUEUED
	 */
	if ((flags & SCSI_POLL) == 0)
		return;

	/*
	 * If we can't use interrupts, poll on completion
	 */
	if ((sc->poll)(sc, xs, mscp->timeout)) {
		uha_timeout(mscp);
		if ((sc->poll)(sc, xs, mscp->timeout))
			uha_timeout(mscp);
	}
	return;

bad:
	xs->error = XS_DRIVER_STUFFUP;
	scsi_done(xs);
	uha_free_mscp(sc, mscp);
	return;
}

void
uha_timeout(arg)
	void *arg;
{
	struct uha_mscp *mscp = arg;
	struct scsi_xfer *xs = mscp->xs;
	struct scsi_link *sc_link = xs->sc_link;
	struct uha_softc *sc = sc_link->adapter_softc;
	int s;

	sc_print_addr(sc_link);
	printf("timed out");

	s = splbio();

	if (mscp->flags & MSCP_ABORT) {
		/* abort timed out */
		printf(" AGAIN\n");
		/* XXX Must reset! */
	} else {
		/* abort the operation that has timed out */
		printf("\n");
		mscp->xs->error = XS_TIMEOUT;
		mscp->timeout = UHA_ABORT_TIMEOUT;
		mscp->flags |= MSCP_ABORT;
		(sc->start_mbox)(sc, mscp);
	}

	splx(s);
}
