/*      $NetBSD: ata.c,v 1.27 2004/01/03 23:59:58 thorpej Exp $      */

/*
 * Copyright (c) 1998, 2001 Manuel Bouyer.  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 Manuel Bouyer.
 * 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ata.c,v 1.27 2004/01/03 23:59:58 thorpej Exp $");

#ifndef WDCDEBUG
#define WDCDEBUG
#endif /* WDCDEBUG */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/device.h>
#include <sys/proc.h>
#include <sys/kthread.h>
#include <sys/errno.h>

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

#include <dev/ata/atareg.h>
#include <dev/ata/atavar.h>
#include <dev/ic/wdcreg.h>
#include <dev/ic/wdcvar.h>

#include "locators.h"

#define DEBUG_FUNCS  0x08
#define DEBUG_PROBE  0x10
#define DEBUG_DETACH 0x20
#ifdef WDCDEBUG
extern int wdcdebug_mask; /* init'ed in wdc.c */
#define WDCDEBUG_PRINT(args, level) \
        if (wdcdebug_mask & (level)) \
		printf args
#else
#define WDCDEBUG_PRINT(args, level)
#endif

/*****************************************************************************
 * ATA bus layer.
 *
 * ATA controllers attach an atabus instance, which handles probing the bus
 * for drives, etc.
 *****************************************************************************/

/*
 * atabusprint:
 *
 *	Autoconfiguration print routine used by ATA controllers when
 *	attaching an atabus instance.
 */
int
atabusprint(void *aux, const char *pnp)
{
	struct wdc_channel *chan = aux;
	
	if (pnp)
		aprint_normal("atabus at %s", pnp);
	aprint_normal(" channel %d", chan->ch_channel);

	return (UNCONF);
}

/*
 * ataprint:
 *
 *	Autoconfiguration print routine.
 */
int
ataprint(void *aux, const char *pnp)
{
	struct ata_device *adev = aux;

	if (pnp)
		aprint_normal("wd at %s", pnp);
	aprint_normal(" drive %d", adev->adev_drv_data->drive);

	return (UNCONF);
}

/*
 * atabus_thread:
 *
 *	Worker thread for the ATA bus.
 */
static void
atabus_thread(void *arg)
{
	struct atabus_softc *sc = arg;
	struct wdc_channel *chp = sc->sc_chan;
	struct ata_xfer *xfer;
	int s;

	s = splbio();
	chp->ch_flags |= WDCF_TH_RUN;
	splx(s);

	/* Configure the devices on the bus. */
	atabusconfig(sc);

	for (;;) {
		s = splbio();
		if ((chp->ch_flags & (WDCF_TH_RESET | WDCF_SHUTDOWN)) == 0 &&
		    ((chp->ch_flags & WDCF_ACTIVE) == 0 ||
		     chp->ch_queue->queue_freeze == 0)) {
			chp->ch_flags &= ~WDCF_TH_RUN;
			(void) tsleep(&chp->ch_thread, PRIBIO, "atath", 0);
			chp->ch_flags |= WDCF_TH_RUN;
		}
		splx(s);
		if (chp->ch_flags & WDCF_SHUTDOWN)
			break;
		s = splbio();
		if (chp->ch_flags & WDCF_TH_RESET) {
			int drive;

			(void) wdcreset(chp, RESET_SLEEP);
			for (drive = 0; drive < 2; drive++)
				chp->ch_drive[drive].state = 0;
			chp->ch_flags &= ~WDCF_TH_RESET;
			chp->ch_queue->queue_freeze--;
			wdcstart(chp);
		} else if ((chp->ch_flags & WDCF_ACTIVE) != 0 &&
			   chp->ch_queue->queue_freeze == 1) {
			/*
			 * Caller has bumped queue_freeze, decrease it.
			 */
			chp->ch_queue->queue_freeze--;
			xfer = TAILQ_FIRST(&chp->ch_queue->queue_xfer);
			KASSERT(xfer != NULL);
			(*xfer->c_start)(chp, xfer);
		} else if (chp->ch_queue->queue_freeze > 1)
			panic("ata_thread: queue_freeze");
		splx(s);
	}
	chp->ch_thread = NULL;
	wakeup(&chp->ch_flags);
	kthread_exit(0);
}

/*
 * atabus_create_thread:
 *
 *	Helper routine to create the ATA bus worker thread.
 */
static void
atabus_create_thread(void *arg)
{
	struct atabus_softc *sc = arg;
	struct wdc_channel *chp = sc->sc_chan;
	int error;

	if ((error = kthread_create1(atabus_thread, sc, &chp->ch_thread,
				     "%s", sc->sc_dev.dv_xname)) != 0)
		aprint_error("%s: unable to create kernel thread: error %d\n",
		    sc->sc_dev.dv_xname, error);
}

/*
 * atabus_match:
 *
 *	Autoconfiguration match routine.
 */
static int
atabus_match(struct device *parent, struct cfdata *cf, void *aux)
{
	struct wdc_channel *chp = aux;

	if (chp == NULL)
		return (0);
	
	if (cf->cf_loc[ATACF_CHANNEL] != chp->ch_channel &&
	    cf->cf_loc[ATACF_CHANNEL] != ATACF_CHANNEL_DEFAULT)
	    	return (0);
	
	return (1);
}

/*
 * atabus_attach:
 *
 *	Autoconfiguration attach routine.
 */
static void
atabus_attach(struct device *parent, struct device *self, void *aux)
{
	struct atabus_softc *sc = (void *) self;
	struct wdc_channel *chp = aux;
	struct atabus_initq *initq;

	sc->sc_chan = chp;

	aprint_normal("\n");
	aprint_naive("\n");

	initq = malloc(sizeof(*initq), M_DEVBUF, M_WAITOK);
	initq->atabus_sc = sc;
	TAILQ_INSERT_TAIL(&atabus_initq_head, initq, atabus_initq);
	config_pending_incr();
	kthread_create(atabus_create_thread, sc);
}

/*
 * atabus_activate:
 *
 *	Autoconfiguration activation routine.
 */
static int
atabus_activate(struct device *self, enum devact act)
{
	struct atabus_softc *sc = (void *) self;
	struct wdc_channel *chp = sc->sc_chan;
	struct device *dev = NULL;
	int s, i, error = 0;

	s = splbio();
	switch (act) {
	case DVACT_ACTIVATE:
		error = EOPNOTSUPP;
		break;
	
	case DVACT_DEACTIVATE:
		/*
		 * We might deactivate the children of atapibus twice
		 * (once bia atapibus, once directly), but since the
		 * generic autoconfiguration code maintains the DVF_ACTIVE
		 * flag, it's safe.
		 */
		if ((dev = chp->atapibus) != NULL) {
			error = config_deactivate(dev);
			if (error)
				goto out;
		}

		for (i = 0; i < 2; i++) {
			if ((dev = chp->ch_drive[i].drv_softc) != NULL) {
				WDCDEBUG_PRINT(("atabus_activate: %s: "
				    "deactivating %s\n", sc->sc_dev.dv_xname,
				    dev->dv_xname),
				    DEBUG_DETACH);
				error = config_deactivate(dev);
				if (error)
					goto out;
			}
		}
		break;
	}
 out:
	splx(s);

#ifdef WDCDEBUG
	if (dev != NULL && error != 0)
		WDCDEBUG_PRINT(("atabus_activate: %s: "
		    "error %d deactivating %s\n", sc->sc_dev.dv_xname,
		    error, dev->dv_xname), DEBUG_DETACH);
#endif /* WDCDEBUG */

	return (error);
}

/*
 * atabus_detach:
 *
 *	Autoconfiguration detach routine.
 */
static int
atabus_detach(struct device *self, int flags)
{
	struct atabus_softc *sc = (void *) self;
	struct wdc_channel *chp = sc->sc_chan;
	struct device *dev = NULL;
	int i, error = 0;

	/* Shutdown the channel. */
	/* XXX NEED AN INTERLOCK HERE. */
	chp->ch_flags |= WDCF_SHUTDOWN;
	wakeup(&chp->ch_thread);
	while (chp->ch_thread != NULL)
		(void) tsleep(&chp->ch_flags, PRIBIO, "atadown", 0);
	
	/*
	 * Detach atapibus and its children.
	 */
	if ((dev = chp->atapibus) != NULL) {
		WDCDEBUG_PRINT(("atabus_detach: %s: detaching %s\n",
		    sc->sc_dev.dv_xname, dev->dv_xname), DEBUG_DETACH);
		error = config_detach(dev, flags);
		if (error)
			goto out;
	}

	/*
	 * Detach our other children.
	 */
	for (i = 0; i < 2; i++) {
		if (chp->ch_drive[i].drive_flags & DRIVE_ATAPI)
			continue;
		if ((dev = chp->ch_drive[i].drv_softc) != NULL) {
			WDCDEBUG_PRINT(("atabus_detach: %s: detaching %s\n",
			    sc->sc_dev.dv_xname, dev->dv_xname),
			    DEBUG_DETACH);
			error = config_detach(dev, flags);
			if (error)
				goto out;
		}
	}

	wdc_kill_pending(chp);
 out:
#ifdef WDCDEBUG
	if (dev != NULL && error != 0)
		WDCDEBUG_PRINT(("atabus_detach: %s: error %d detaching %s\n",
		    sc->sc_dev.dv_xname, error, dev->dv_xname),
		    DEBUG_DETACH);
#endif /* WDCDEBUG */

	return (error);
}

CFATTACH_DECL(atabus, sizeof(struct atabus_softc),
    atabus_match, atabus_attach, atabus_detach, atabus_activate);

/*****************************************************************************
 * Common ATA bus operations.
 *****************************************************************************/

/* Get the disk's parameters */
int
ata_get_params(struct ata_drive_datas *drvp, u_int8_t flags,
    struct ataparams *prms)
{
	char tb[DEV_BSIZE];
	struct wdc_command wdc_c;

#if BYTE_ORDER == LITTLE_ENDIAN
	int i;
	u_int16_t *p;
#endif

	WDCDEBUG_PRINT(("ata_get_parms\n"), DEBUG_FUNCS);

	memset(tb, 0, DEV_BSIZE);
	memset(prms, 0, sizeof(struct ataparams));
	memset(&wdc_c, 0, sizeof(struct wdc_command));

	if (drvp->drive_flags & DRIVE_ATA) {
		wdc_c.r_command = WDCC_IDENTIFY;
		wdc_c.r_st_bmask = WDCS_DRDY;
		wdc_c.r_st_pmask = 0;
		wdc_c.timeout = 3000; /* 3s */
	} else if (drvp->drive_flags & DRIVE_ATAPI) {
		wdc_c.r_command = ATAPI_IDENTIFY_DEVICE;
		wdc_c.r_st_bmask = 0;
		wdc_c.r_st_pmask = 0;
		wdc_c.timeout = 10000; /* 10s */
	} else {
		WDCDEBUG_PRINT(("ata_get_parms: no disks\n"),
		    DEBUG_FUNCS|DEBUG_PROBE);
		return CMD_ERR;
	}
	wdc_c.flags = AT_READ | flags;
	wdc_c.data = tb;
	wdc_c.bcount = DEV_BSIZE;
	if (wdc_exec_command(drvp, &wdc_c) != WDC_COMPLETE) {
		WDCDEBUG_PRINT(("ata_get_parms: wdc_exec_command failed\n"),
		    DEBUG_FUNCS|DEBUG_PROBE);
		return CMD_AGAIN;
	}
	if (wdc_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
		WDCDEBUG_PRINT(("ata_get_parms: wdc_c.flags=0x%x\n",
		    wdc_c.flags), DEBUG_FUNCS|DEBUG_PROBE);
		return CMD_ERR;
	} else {
		/* if we didn't read any data something is wrong */
		if ((wdc_c.flags & AT_XFDONE) == 0)
			return CMD_ERR;
		/* Read in parameter block. */
		memcpy(prms, tb, sizeof(struct ataparams));
#if BYTE_ORDER == LITTLE_ENDIAN
		/*
		 * Shuffle string byte order.
		 * ATAPI Mitsumi and NEC drives don't need this.
		 */
		if ((prms->atap_config & WDC_CFG_ATAPI_MASK) ==
		    WDC_CFG_ATAPI &&
		    ((prms->atap_model[0] == 'N' &&
			prms->atap_model[1] == 'E') ||
		     (prms->atap_model[0] == 'F' &&
			 prms->atap_model[1] == 'X')))
			return 0;
		for (i = 0; i < sizeof(prms->atap_model); i += 2) {
			p = (u_short *)(prms->atap_model + i);
			*p = ntohs(*p);
		}
		for (i = 0; i < sizeof(prms->atap_serial); i += 2) {
			p = (u_short *)(prms->atap_serial + i);
			*p = ntohs(*p);
		}
		for (i = 0; i < sizeof(prms->atap_revision); i += 2) {
			p = (u_short *)(prms->atap_revision + i);
			*p = ntohs(*p);
		}
#endif
		return CMD_OK;
	}
}

int
ata_set_mode(struct ata_drive_datas *drvp, u_int8_t mode, u_int8_t flags)
{
	struct wdc_command wdc_c;

	WDCDEBUG_PRINT(("ata_set_mode=0x%x\n", mode), DEBUG_FUNCS);
	memset(&wdc_c, 0, sizeof(struct wdc_command));

	wdc_c.r_command = SET_FEATURES;
	wdc_c.r_st_bmask = 0;
	wdc_c.r_st_pmask = 0;
	wdc_c.r_precomp = WDSF_SET_MODE;
	wdc_c.r_count = mode;
	wdc_c.flags = flags;
	wdc_c.timeout = 1000; /* 1s */
	if (wdc_exec_command(drvp, &wdc_c) != WDC_COMPLETE)
		return CMD_AGAIN;
	if (wdc_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
		return CMD_ERR;
	}
	return CMD_OK;
}

void
ata_dmaerr(struct ata_drive_datas *drvp, int flags)
{
	/*
	 * Downgrade decision: if we get NERRS_MAX in NXFER.
	 * We start with n_dmaerrs set to NERRS_MAX-1 so that the
	 * first error within the first NXFER ops will immediatly trigger
	 * a downgrade.
	 * If we got an error and n_xfers is bigger than NXFER reset counters.
	 */
	drvp->n_dmaerrs++;
	if (drvp->n_dmaerrs >= NERRS_MAX && drvp->n_xfers <= NXFER) {
		wdc_downgrade_mode(drvp, flags);
		drvp->n_dmaerrs = NERRS_MAX-1;
		drvp->n_xfers = 0;
		return;
	}
	if (drvp->n_xfers > NXFER) {
		drvp->n_dmaerrs = 1; /* just got an error */
		drvp->n_xfers = 1; /* restart counting from this error */
	}
}