/*
 * (MPSAFE)
 *
 * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 *
 * 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. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``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
 * COPYRIGHT HOLDERS OR CONTRIBUTORS 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 "sili.h"

static void sili_pm_dummy_done(struct ata_xfer *xa);
static void sili_pm_empty_done(struct sili_ccb *ccb);

/*
 * This is called for PM attachments and hot-plug insertion events, and
 * typically not called again until after an unplug/replug sequence.
 *
 * We just fall through to the hard-reset code, we don't need to
 * set up any initial conditions.
 */
int
sili_pm_port_init(struct sili_port *ap, struct ata_port *at)
{
        at->at_probe = ATA_PROBE_NEED_HARD_RESET;
        return (0);
}

/*
 * This is called from the port hardreset code.
 */
int
sili_pm_port_probe(struct sili_port *ap, int orig_error)
{
        struct ata_port *at;
        int error;
        int i;

        /*
         * Clean up the port state machine
         */
        sili_pwrite(ap, SILI_PREG_CTL_SET, SILI_PREG_CTL_PMA);
        sili_pwrite(ap, SILI_PREG_CTL_SET, SILI_PREG_CTL_INIT);
        if (sili_pwait_clr_to(ap, 5000, SILI_PREG_STATUS, SILI_PREG_CTL_INIT)) {
                kprintf("%s: PM probe: unable to init port\n",
                        PORTNAME(ap));
                return (EBUSY);
        }
        if (sili_pwait_set(ap, SILI_PREG_STATUS, SILI_PREG_STATUS_READY)) {
                kprintf("%s: PM probe: port will not come ready\n",
                        PORTNAME(ap));
                return (EBUSY);
        }

        /*
         * Issue a soft-reset of target 15
         */
        ap->ap_state = AP_S_NORMAL;
        sili_pwrite(ap, SILI_PREG_SERR, -1);
        error = sili_pm_softreset(ap, 15);

        if (error == 0)
                error = sili_pm_identify(ap);

        /*
         * Finalize.  If the softreset failed.  Re-init the port
         * state machine again so the normal non-PM softreset does
         * not bog down.
         */
        if (error == 0) {
                for (i = 0; i < SILI_MAX_PMPORTS; ++i) {
                        at = &ap->ap_ata[i];
                        at->at_probe = ATA_PROBE_NEED_INIT;
                        at->at_features |= ATA_PORT_F_RESCAN;
                        at->at_features &= ~ATA_PORT_F_READLOG;
                }
                ap->ap_type = ATA_PORT_T_PM;
                return (0);
        }

        sili_pwrite(ap, SILI_PREG_CTL_CLR, SILI_PREG_CTL_PMA);
        sili_port_init(ap);
        if (orig_error == 0) {
                if (sili_pwait_set_to(ap, 5000, SILI_PREG_STATUS,
                                      SILI_PREG_STATUS_READY)) {
                        kprintf("%s: PM probe: port will not come ready\n",
                                PORTNAME(ap));
                        orig_error = EBUSY;
                }
        }
        return (orig_error);

#if 0
        sili_pwrite(ap, SILI_PREG_CTL_CLR, SILI_PREG_CTL_RESUME);
        sili_pwrite(ap, SILI_PREG_CTL_CLR, SILI_PREG_CTL_PMA);
        sili_pwrite(ap, SILI_PREG_CTL_SET, SILI_PREG_CTL_INIT);
        if (sili_pwait_clr_to(ap, 5000, SILI_PREG_STATUS, SILI_PREG_CTL_INIT)) {
                kprintf("%s: PM probe: unable to init port\n",
                        PORTNAME(ap));
                orig_error = EBUSY;
        }
        if (sili_pwait_set(ap, SILI_PREG_STATUS, SILI_PREG_STATUS_READY)) {
                kprintf("%s: PM probe: port will not come ready\n",
                        PORTNAME(ap));
                orig_error = EBUSY;
        }
        kprintf("ORIG ERROR %d\n", orig_error);
        if (orig_error)
                return (orig_error);

        /*
         * If we originally detected a device redo the device reset to
         * try to clear the mess.
         */
        sili_pwrite(ap, SILI_PREG_CTL_SET, SILI_PREG_CTL_DEVRESET);
        if (sili_pwait_clr(ap, SILI_PREG_CTL_SET, SILI_PREG_CTL_DEVRESET)) {
                kprintf("%s: PM probe: unable to reset\n", PORTNAME(ap));
                orig_error = EBUSY;
        }
        if (sili_pwait_set(ap, SILI_PREG_STATUS, SILI_PREG_STATUS_READY)) {
                kprintf("%s: PM probe: port will not come ready\n",
                        PORTNAME(ap));
                orig_error = EBUSY;
        }
        return (orig_error);
#endif
}

/*
 * Identify the port multiplier
 */
int
sili_pm_identify(struct sili_port *ap)
{
        u_int32_t chipid;
        u_int32_t rev;
        u_int32_t nports;
        u_int32_t data1;
        u_int32_t data2;
        int       has_dummy_port;

        ap->ap_probe = ATA_PROBE_FAILED;
        if (sili_pm_read(ap, 15, 0, &chipid))
                goto err;
        if (sili_pm_read(ap, 15, 1, &rev))
                goto err;
        if (sili_pm_read(ap, 15, 2, &nports))
                goto err;
        nports &= 0x0000000F;   /* only the low 4 bits */
        ap->ap_probe = ATA_PROBE_GOOD;

        /*
         * Ignore fake port on PMs which have it.  We can probe it but the
         * softreset will probably fail.
         */
        switch(chipid) {
        case 0x37261095:
                has_dummy_port = 1;
                break;
        default:
                has_dummy_port = 0;
                break;
        }
        if (has_dummy_port) {
                if (nports > 1)
                        --nports;
        }

        kprintf("%s: Port multiplier: chip=%08x rev=0x%pb%i nports=%d\n",
                PORTNAME(ap),
                chipid,
                SATA_PFMT_PM_REV, rev,
                nports);
        if (has_dummy_port) {
                kprintf("%s: Port multiplier: Ignoring dummy port #%d\n",
                        PORTNAME(ap), nports);
        }
        ap->ap_pmcount = nports;

        if (sili_pm_read(ap, 15, SATA_PMREG_FEA, &data1)) {
                kprintf("%s: Port multiplier: Warning, "
                        "cannot read feature register\n", PORTNAME(ap));
        } else {
                kprintf("%s: Port multiplier features: 0x%pb%i\n",
                        PORTNAME(ap), SATA_PFMT_PM_FEA, data1);
        }
        if (sili_pm_read(ap, 15, SATA_PMREG_FEAEN, &data2) == 0) {
                kprintf("%s: Port multiplier defaults: 0x%pb%i\n",
                        PORTNAME(ap), SATA_PFMT_PM_FEA, data2);
        }

        /*
         * Turn on async notification if we support and the PM supports it.
         * This allows the PM to forward async notification events to us and
         * it will also generate an event for target 15 for hot-plug events
         * (or is supposed to anyway).
         */
        if ((ap->ap_sc->sc_flags & SILI_F_SSNTF) &&
            (data1 & SATA_PMFEA_ASYNCNOTIFY)) {
                u_int32_t serr_bits = SATA_PM_SERR_DIAG_N |
                                      SATA_PM_SERR_DIAG_X;
                data2 |= SATA_PMFEA_ASYNCNOTIFY;
                if (sili_pm_write(ap, 15, SATA_PMREG_FEAEN, data2)) {
                        kprintf("%s: Port multiplier: AsyncNotify cannot be "
                                "enabled\n", PORTNAME(ap));
                } else if (sili_pm_write(ap, 15, SATA_PMREG_EEENA, serr_bits)) {
                        kprintf("%s: Port mulltiplier: AsyncNotify unable "
                                "to enable error info bits\n", PORTNAME(ap));
                } else {
                        kprintf("%s: Port multiplier: AsyncNotify enabled\n",
                                PORTNAME(ap));
                }
        }

        return (0);
err:
        kprintf("%s: Port multiplier cannot be identified\n", PORTNAME(ap));
        return (EIO);
}

/*
 * Do a COMRESET sequence on the target behind a port multiplier.
 *
 * If hard is 2 we also cycle the phy on the target.
 *
 * This must be done prior to any softreset or probe attempts on
 * targets behind the port multiplier.
 *
 * Returns 0 on success or an error.
 */
int
sili_pm_hardreset(struct sili_port *ap, int target, int hard)
{
        struct ata_port *at;
        u_int32_t data;
        int loop;
        int error = EIO;

        at = &ap->ap_ata[target];

        /*
         * Ensure that no other commands are pending.  Our HW reset of
         * the PM target can skewer the port overall!
         */
        sili_exclusive_access(ap);

        /*
         * Turn off power management and kill the phy on the target
         * if requested.  Hold state for 10ms.
         */
        data = SATA_PM_SCTL_IPM_DISABLED;
#if 0
        if (hard == 2)
                data |= SATA_PM_SCTL_DET_DISABLE;
#endif
        if (sili_pm_write(ap, target, SATA_PMREG_SERR, -1))
                goto err;
        if (sili_pm_write(ap, target, SATA_PMREG_SCTL, data))
                goto err;
        sili_os_sleep(10);

        /*
         * Start transmitting COMRESET.  COMRESET must be sent for at
         * least 1ms.
         *
         * It takes about 100ms for the DET logic to settle down,
         * from trial and error testing.  If this is too short
         * the softreset code will fail.
         *
         * It is very important to allow the logic to settle before
         * we issue any additional commands or the target will interfere
         * with our PM commands.
         */
        at->at_probe = ATA_PROBE_FAILED;
        at->at_type = ATA_PORT_T_NONE;
        data = SATA_PM_SCTL_IPM_DISABLED | SATA_PM_SCTL_DET_INIT;
        if (SiliForceGen1 & (1 << ap->ap_num)) {
                kprintf("%s.%d: Force 1.5GBits\n", PORTNAME(ap), target);
                data |= SATA_PM_SCTL_SPD_GEN1;
        } else {
                data |= SATA_PM_SCTL_SPD_ANY;
        }
        if (sili_pm_write(ap, target, SATA_PMREG_SCTL, data))
                goto err;
        sili_os_sleep(100);

        if (sili_pm_phy_status(ap, target, &data)) {
                kprintf("%s: (A)Cannot clear phy status\n",
                        ATANAME(ap ,at));
        }

        /*
         * Flush any status, then clear DET to initiate negotiation.
         *
         * It is very important to allow the negotiation to settle before
         * we issue any additional commands or the target will interfere
         * with our PM commands.
         */
        sili_pm_write(ap, target, SATA_PMREG_SERR, -1);
        data = SATA_PM_SCTL_IPM_DISABLED | SATA_PM_SCTL_DET_NONE;
        if (sili_pm_write(ap, target, SATA_PMREG_SCTL, data))
                goto err;
        sili_os_sleep(100);

        /*
         * Try to determine if there is a device on the port.
         *
         * Give the device 3/10 second to at least be detected.
         * If we fail clear any pending status since we may have
         * cycled the phy and probably caused another PRCS interrupt.
         */
        for (loop = 3; loop; --loop) {
                if (sili_pm_read(ap, target, SATA_PMREG_SSTS, &data))
                        goto err;
                if (data & SATA_PM_SSTS_DET)
                        break;
                sili_os_sleep(100);
        }
        if (loop == 0) {
                kprintf("%s.%d: Port appears to be unplugged\n",
                        PORTNAME(ap), target);
                error = ENODEV;
                goto err;
        }

        /*
         * There is something on the port.  Give the device 3 seconds
         * to fully negotiate.
         */
        for (loop = 30; loop; --loop) {
                if (sili_pm_read(ap, target, SATA_PMREG_SSTS, &data))
                        goto err;
                if ((data & SATA_PM_SSTS_DET) == SATA_PM_SSTS_DET_DEV)
                        break;
                sili_os_sleep(100);
        }

        /*
         * Device not detected
         */
        if (loop == 0) {
                kprintf("%s: Device may be powered down\n",
                        PORTNAME(ap));
                error = ENODEV;
                goto err;
        }

        /*
         * Device detected.
         *
         * Wait 200ms to give the device time to send its first D2H FIS.
         * If we do not wait long enough our softreset sequence can collide
         * with the end of the device's reset sequence and brick the port.
         * Some devices may need longer and we handle those cases in the
         * pm softreset code.
         *
         * XXX Looks like we have to wait a lot longer.  If the Sili chip's
         *     softreset fails due to a collision with the D2H FIS or the
         *     unbusying it bricks the port.
         *
         * XXX how do we poll that particular target's BSY status via the
         *     PM?
         */
        kprintf("%s.%d: PM Device detected ssts=%08x\n",
                PORTNAME(ap), target, data);
        sili_os_sleep(5000);

        error = 0;
err:
        at->at_probe = error ? ATA_PROBE_FAILED : ATA_PROBE_NEED_SOFT_RESET;
        return (error);
}

/*
 * SILI soft reset through port multiplier.
 *
 * This function generates a soft reset through the port multiplier,
 * keeping port communications intact.
 *
 * The SII chip will do the whole mess for us.  However, the command
 * can brick the port if the target is still busy from the previous
 * COMRESET.
 */
int
sili_pm_softreset(struct sili_port *ap, int target)
{
        struct ata_port         *at;
        struct sili_ccb         *ccb;
        struct sili_prb         *prb;
        int                     error;
        u_int32_t               data;
        u_int32_t               sig;
        int                     timeout;

        error = EIO;
        at = &ap->ap_ata[target];

        kprintf("%s: PM softreset\n", ATANAME(ap, at));

        /*
         * Prep the special soft-reset SII command.
         */
        ccb = sili_get_err_ccb(ap);
        ccb->ccb_done = sili_pm_empty_done;
        ccb->ccb_xa.flags = ATA_F_POLL | ATA_F_EXCLUSIVE | ATA_F_AUTOSENSE;
        ccb->ccb_xa.complete = sili_pm_dummy_done;
        ccb->ccb_xa.at = at;

        prb = ccb->ccb_prb;
        bzero(&prb->prb_h2d, sizeof(prb->prb_h2d));
        prb->prb_h2d.flags = at->at_target;
        prb->prb_control = SILI_PRB_CTRL_SOFTRESET;
        prb->prb_override = 0;
        prb->prb_xfer_count = 0;

        ccb->ccb_xa.state = ATA_S_PENDING;

        timeout = (target == 15) ? 1000 : 8000;

        /*
         * NOTE: Must use sili_quick_timeout() because we hold the err_ccb
         */
        if (sili_poll(ccb, timeout, sili_quick_timeout) != ATA_S_COMPLETE) {
                if (target != 15) {
                        kprintf("%s: (PM) Softreset FIS failed\n",
                                ATANAME(ap, at));
                }
                sili_put_err_ccb(ccb);
                goto err;
        }

        sig = (prb->prb_d2h.lba_high << 24) |
              (prb->prb_d2h.lba_mid << 16) |
              (prb->prb_d2h.lba_low << 8) |
              (prb->prb_d2h.sector_count);
        kprintf("%s: PM SOFTRESET SIGNATURE %08x\n", ATANAME(ap, at), sig);

        sili_put_err_ccb(ccb);

        /*
         * Clear the phy status of the target so we can get a new event.
         *
         * Target 15 is the PM itself and these registers have
         * different meanings.
         */
        if (target != 15) {
                if (sili_pm_phy_status(ap, target, &data)) {
                        kprintf("%s: (C)Cannot clear phy status\n",
                                ATANAME(ap ,at));
                }
                sili_pm_write(ap, target, SATA_PMREG_SERR, -1);
        }

        /*
         * If the softreset is trying to clear a BSY condition after a
         * normal portreset we assign the port type.
         *
         * If the softreset is being run first as part of the ccb error
         * processing code then report if the device signature changed
         * unexpectedly.
         */
        if (at->at_type == ATA_PORT_T_NONE) {
                at->at_type = sili_port_signature(ap, at, sig);
        } else {
                if (sili_port_signature(ap, at, sig) != at->at_type) {
                        kprintf("%s: device signature unexpectedly "
                                "changed\n", ATANAME(ap, at));
                        error = EBUSY; /* XXX */
                }
        }
        error = 0;
err:
        /*
         * Clear error status so we can detect removal.
         *
         * Target 15 is the PM itself and these registers have
         * different meanings.
         */
        kprintf("%s: PM softreset done error %d\n", ATANAME(ap, at), error);
        if (error == 0 && target != 15) {
                if (sili_pm_write(ap, target, SATA_PMREG_SERR, -1)) {
                        kprintf("%s: sili_pm_softreset unable to clear SERR\n",
                                ATANAME(ap, at));
                        ap->ap_flags &= ~AP_F_IGNORE_IFS;
                }
        }

        at->at_probe = error ? ATA_PROBE_FAILED : ATA_PROBE_NEED_IDENT;
        return (error);
}


/*
 * Return the phy status for a target behind a port multiplier and
 * reset SATA_PMREG_SERR.
 *
 * Returned bits follow SILI_PREG_SSTS bits.  The SILI_PREG_SSTS_SPD
 * bits can be used to determine the link speed and will be 0 if there
 * is no link.
 *
 * 0 is returned if any communications error occurs.
 */
int
sili_pm_phy_status(struct sili_port *ap, int target, u_int32_t *datap)
{
        int error;

        error = sili_pm_read(ap, target, SATA_PMREG_SSTS, datap);
        if (error == 0)
                error = sili_pm_write(ap, target, SATA_PMREG_SERR, -1);
        if (error)
                *datap = 0;
        return(error);
}

int
sili_pm_set_feature(struct sili_port *ap, int feature, int enable)
{
        struct ata_xfer *xa;
        int error;

        xa = sili_ata_get_xfer(ap, &ap->ap_ata[15]);

        xa->fis->type = ATA_FIS_TYPE_H2D;
        xa->fis->flags = ATA_H2D_FLAGS_CMD | 15;
        xa->fis->command = enable ? ATA_C_SATA_FEATURE_ENA :
                                    ATA_C_SATA_FEATURE_DIS;
        xa->fis->sector_count = feature;
        xa->fis->control = ATA_FIS_CONTROL_4BIT;

        xa->complete = sili_pm_dummy_done;
        xa->datalen = 0;
        xa->flags = ATA_F_POLL | ATA_F_EXCLUSIVE;
        xa->timeout = 1000;

        if (sili_ata_cmd(xa) == ATA_S_COMPLETE)
                error = 0;
        else
                error = EIO;
        sili_ata_put_xfer(xa);
        return(error);
}

/*
 * Check that a target is still good.
 */
void
sili_pm_check_good(struct sili_port *ap, int target)
{
        struct ata_port *at;
        u_int32_t data;

        /*
         * It looks like we might have to read the EINFO register
         * to allow the PM to generate a new event.
         */
        if (sili_pm_read(ap, 15, SATA_PMREG_EINFO, &data)) {
                kprintf("%s: Port multiplier EINFO could not be read\n",
                        PORTNAME(ap));
        }

        if (sili_pm_write(ap, target, SATA_PMREG_SERR, -1)) {
                kprintf("%s: Port multiplier: SERR could not be cleared\n",
                        PORTNAME(ap));
        }

        if (target == CAM_TARGET_WILDCARD || target >= ap->ap_pmcount)
                return;
        at = &ap->ap_ata[target];

        /*
         * If the device needs an init or hard reset also make sure the
         * PHY is turned on.
         */
        if (at->at_probe <= ATA_PROBE_NEED_HARD_RESET) {
                /*kprintf("%s DOHARD\n", ATANAME(ap, at));*/
                sili_pm_hardreset(ap, target, 1);
        }

        /*
         * Read the detect status
         */
        if (sili_pm_read(ap, target, SATA_PMREG_SSTS, &data)) {
                kprintf("%s: Unable to access PM SSTS register target %d\n",
                        PORTNAME(ap), target);
                return;
        }
        if ((data & SATA_PM_SSTS_DET) != SATA_PM_SSTS_DET_DEV) {
                /*kprintf("%s: DETECT %08x\n", ATANAME(ap, at), data);*/
                if (at->at_probe != ATA_PROBE_FAILED) {
                        at->at_probe = ATA_PROBE_FAILED;
                        at->at_type = ATA_PORT_T_NONE;
                        at->at_features |= ATA_PORT_F_RESCAN;
                        kprintf("%s: HOTPLUG (PM) - Device removed\n",
                                ATANAME(ap, at));
                }
        } else {
                if (at->at_probe == ATA_PROBE_FAILED) {
                        at->at_probe = ATA_PROBE_NEED_HARD_RESET;
                        at->at_features |= ATA_PORT_F_RESCAN;
                        kprintf("%s: HOTPLUG (PM) - Device inserted\n",
                                ATANAME(ap, at));
                }
        }
}

/*
 * Read a PM register
 */
int
sili_pm_read(struct sili_port *ap, int target, int which, u_int32_t *datap)
{
        struct ata_xfer *xa;
        int error;

        xa = sili_ata_get_xfer(ap, &ap->ap_ata[15]);

        xa->fis->type = ATA_FIS_TYPE_H2D;
        xa->fis->flags = ATA_H2D_FLAGS_CMD | 15;
        xa->fis->command = ATA_C_READ_PM;
        xa->fis->features = which;
        xa->fis->device = target | ATA_H2D_DEVICE_LBA;
        xa->fis->control = ATA_FIS_CONTROL_4BIT;

        xa->complete = sili_pm_dummy_done;
        xa->datalen = 0;
        xa->flags = ATA_F_POLL | ATA_F_AUTOSENSE;
        xa->timeout = 1000;

        if (sili_ata_cmd(xa) == ATA_S_COMPLETE) {
                *datap = xa->rfis->sector_count | (xa->rfis->lba_low << 8) |
                       (xa->rfis->lba_mid << 16) | (xa->rfis->lba_high << 24);
                error = 0;
        } else {
                kprintf("%s.%d pm_read SCA[%d] failed\n",
                        PORTNAME(ap), target, which);
                *datap = 0;
                error = EIO;
        }
        sili_ata_put_xfer(xa);
        return (error);
}

/*
 * Write a PM register
 */
int
sili_pm_write(struct sili_port *ap, int target, int which, u_int32_t data)
{
        struct ata_xfer *xa;
        int error;

        xa = sili_ata_get_xfer(ap, &ap->ap_ata[15]);

        xa->fis->type = ATA_FIS_TYPE_H2D;
        xa->fis->flags = ATA_H2D_FLAGS_CMD | 15;
        xa->fis->command = ATA_C_WRITE_PM;
        xa->fis->features = which;
        xa->fis->device = target | ATA_H2D_DEVICE_LBA;
        xa->fis->sector_count = (u_int8_t)data;
        xa->fis->lba_low = (u_int8_t)(data >> 8);
        xa->fis->lba_mid = (u_int8_t)(data >> 16);
        xa->fis->lba_high = (u_int8_t)(data >> 24);
        xa->fis->control = ATA_FIS_CONTROL_4BIT;

        xa->complete = sili_pm_dummy_done;
        xa->datalen = 0;
        xa->flags = ATA_F_POLL | ATA_F_EXCLUSIVE;
        xa->timeout = 1000;

        if (sili_ata_cmd(xa) == ATA_S_COMPLETE)
                error = 0;
        else
                error = EIO;
        sili_ata_put_xfer(xa);
        return(error);
}

/*
 * Dummy done callback for xa.
 */
static void
sili_pm_dummy_done(struct ata_xfer *xa)
{
}

static void
sili_pm_empty_done(struct sili_ccb *ccb)
{
}