/*-
 * Copyright (c) 1999,2000 Jonathan Lemon
 * All rights reserved.
 *
 # Derived from the original IDA Compaq RAID driver, which is
 * Copyright (c) 1996, 1997, 1998, 1999
 *    Mark Dawson and David James. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD: src/sys/dev/ida/ida.c,v 1.7.2.3 2001/03/01 01:57:32 ps Exp $
 */

/*
 * Generic driver for Compaq SMART RAID adapters.
 *
 * Specific probe routines are in:
 *      dev/raid/ida/ida_pci.c
 */

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/bus.h>
#include <sys/devicestat.h>
#include <sys/disk.h>
#include <sys/rman.h>
#include <sys/buf2.h>
#include <sys/thread2.h>

#include <machine/clock.h>

#include "idareg.h"
#include "idavar.h"

/* prototypes */
static void ida_alloc_qcb(struct ida_softc *ida);
static void ida_construct_qcb(struct ida_softc *ida);
static void ida_start(struct ida_softc *ida);
static void ida_done(struct ida_softc *ida, struct ida_qcb *qcb);
static int ida_wait(struct ida_softc *ida, struct ida_qcb *qcb);

DECLARE_DUMMY_MODULE(ida);

void
ida_free(struct ida_softc *ida)
{
        int i;

        for (i = 0; i < ida->num_qcbs; i++)
                bus_dmamap_destroy(ida->buffer_dmat, ida->qcbs[i].dmamap);

        if (ida->hwqcb_busaddr)
                bus_dmamap_unload(ida->hwqcb_dmat, ida->hwqcb_dmamap);

        if (ida->hwqcbs)
                bus_dmamem_free(ida->hwqcb_dmat, ida->hwqcbs,
                    ida->hwqcb_dmamap);

        if (ida->buffer_dmat)
                bus_dma_tag_destroy(ida->buffer_dmat);

        if (ida->hwqcb_dmat)
                bus_dma_tag_destroy(ida->hwqcb_dmat);

        if (ida->qcbs != NULL)
                kfree(ida->qcbs, M_DEVBUF);

        if (ida->ih != NULL)
                bus_teardown_intr(ida->dev, ida->irq, ida->ih);

        if (ida->irq != NULL)
                bus_release_resource(ida->dev, ida->irq_res_type,
                    0, ida->irq);

        if (ida->parent_dmat != NULL)
                bus_dma_tag_destroy(ida->parent_dmat);

        if (ida->regs != NULL)
                bus_release_resource(ida->dev, ida->regs_res_type,
                    ida->regs_res_id, ida->regs);
}

/*
 * record bus address from bus_dmamap_load
 */
static void
ida_dma_map_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error) 
{
        bus_addr_t *baddr;

        baddr = (bus_addr_t *)arg;
        *baddr = segs->ds_addr;
}

static __inline struct ida_qcb *
ida_get_qcb(struct ida_softc *ida)
{
        struct ida_qcb *qcb;

        if ((qcb = SLIST_FIRST(&ida->free_qcbs)) != NULL) {
                SLIST_REMOVE_HEAD(&ida->free_qcbs, link.sle);
        } else {
                ida_alloc_qcb(ida);
                if ((qcb = SLIST_FIRST(&ida->free_qcbs)) != NULL)
                        SLIST_REMOVE_HEAD(&ida->free_qcbs, link.sle);
        }
        return (qcb);
}

static __inline bus_addr_t
idahwqcbvtop(struct ida_softc *ida, struct ida_hardware_qcb *hwqcb)
{
        return (ida->hwqcb_busaddr +
            ((bus_addr_t)hwqcb - (bus_addr_t)ida->hwqcbs));
}

static __inline struct ida_qcb *
idahwqcbptov(struct ida_softc *ida, bus_addr_t hwqcb_addr)
{
        struct ida_hardware_qcb *hwqcb;

        hwqcb = (struct ida_hardware_qcb *)
            ((bus_addr_t)ida->hwqcbs + (hwqcb_addr - ida->hwqcb_busaddr));
        return (hwqcb->qcb);
}

/*
 * XXX
 * since we allocate all QCB space up front during initialization, then
 * why bother with this routine?
 */
static void
ida_alloc_qcb(struct ida_softc *ida)
{
        struct ida_qcb *qcb;
        int error;

        if (ida->num_qcbs >= IDA_QCB_MAX)
                return;

        qcb = &ida->qcbs[ida->num_qcbs];

        error = bus_dmamap_create(ida->buffer_dmat, /*flags*/0, &qcb->dmamap);
        if (error != 0)
                return;

        qcb->flags = QCB_FREE;
        qcb->hwqcb = &ida->hwqcbs[ida->num_qcbs];
        qcb->hwqcb->qcb = qcb;
        qcb->hwqcb_busaddr = idahwqcbvtop(ida, qcb->hwqcb);
        SLIST_INSERT_HEAD(&ida->free_qcbs, qcb, link.sle);
        ida->num_qcbs++;
}

int
ida_init(struct ida_softc *ida)
{
        int error;

        ida->unit = device_get_unit(ida->dev);
        ida->tag = rman_get_bustag(ida->regs);
        ida->bsh = rman_get_bushandle(ida->regs);

        SLIST_INIT(&ida->free_qcbs);
        STAILQ_INIT(&ida->qcb_queue);
        bioq_init(&ida->bio_queue);

        ida->qcbs = kmalloc(IDA_QCB_MAX * sizeof(struct ida_qcb), 
                            M_DEVBUF, M_INTWAIT|M_ZERO);

        /*
         * Create our DMA tags
         */

        /* DMA tag for our hardware QCB structures */
        error = bus_dma_tag_create(ida->parent_dmat,
            /*alignment*/1, /*boundary*/0,
            /*lowaddr*/BUS_SPACE_MAXADDR, /*highaddr*/BUS_SPACE_MAXADDR,
            IDA_QCB_MAX * sizeof(struct ida_hardware_qcb),
            /*nsegments*/1, /*maxsegsz*/BUS_SPACE_MAXSIZE_32BIT,
            /*flags*/0, &ida->hwqcb_dmat);
        if (error)
                return (ENOMEM);

        /* DMA tag for mapping buffers into device space */
        error = bus_dma_tag_create(ida->parent_dmat,
            /*alignment*/1, /*boundary*/0,
            /*lowaddr*/BUS_SPACE_MAXADDR, /*highaddr*/BUS_SPACE_MAXADDR,
            /*maxsize*/MAXBSIZE, /*nsegments*/IDA_NSEG,
            /*maxsegsz*/BUS_SPACE_MAXSIZE_32BIT, /*flags*/0, &ida->buffer_dmat);
        if (error)
                return (ENOMEM);

        /* Allocation of hardware QCBs */
        /* XXX allocation is rounded to hardware page size */
        error = bus_dmamem_alloc(ida->hwqcb_dmat,
            (void *)&ida->hwqcbs, BUS_DMA_NOWAIT, &ida->hwqcb_dmamap);
        if (error)
                return (ENOMEM);

        /* And permanently map them in */
        bus_dmamap_load(ida->hwqcb_dmat, ida->hwqcb_dmamap,
            ida->hwqcbs, IDA_QCB_MAX * sizeof(struct ida_hardware_qcb),
            ida_dma_map_cb, &ida->hwqcb_busaddr, /*flags*/0);

        bzero(ida->hwqcbs, IDA_QCB_MAX * sizeof(struct ida_hardware_qcb));

        ida_alloc_qcb(ida);             /* allocate an initial qcb */

        return (0);
}

void
ida_attach(struct ida_softc *ida)
{
        struct ida_controller_info cinfo;
        int error, i;

        ida->cmd.int_enable(ida, 0);

        error = ida_command(ida, CMD_GET_CTRL_INFO, &cinfo, sizeof(cinfo),
            IDA_CONTROLLER, 0, DMA_DATA_IN);
        if (error) {
                device_printf(ida->dev, "CMD_GET_CTRL_INFO failed.\n");
                return;
        }

        device_printf(ida->dev, "drives=%d firm_rev=%c%c%c%c\n",
            cinfo.num_drvs, cinfo.firm_rev[0], cinfo.firm_rev[1],
            cinfo.firm_rev[2], cinfo.firm_rev[3]);

        if (ida->flags & IDA_FIRMWARE) {
                int data;

                error = ida_command(ida, CMD_START_FIRMWARE,
                    &data, sizeof(data), IDA_CONTROLLER, 0, DMA_DATA_IN);
                if (error) {
                        device_printf(ida->dev, "CMD_START_FIRMWARE failed.\n");
                        return;
                }
        }

        ida->num_drives = 0;
        for (i = 0; i < cinfo.num_drvs; i++)
                device_add_child(ida->dev, /*"idad"*/NULL, -1);

        bus_generic_attach(ida->dev);

        ida->cmd.int_enable(ida, 1);
}

int
ida_detach(device_t dev)
{
        struct ida_softc *ida;
        int error = 0;

        ida = (struct ida_softc *)device_get_softc(dev);

        /*
         * XXX
         * before detaching, we must make sure that the system is 
         * quiescent; nothing mounted, no pending activity.
         */

        /*
         * XXX
         * now, how are we supposed to maintain a list of our drives?
         * iterate over our "child devices"?
         */


        ida_free(ida);
        return (error);
}

static void
ida_setup_dmamap(void *arg, bus_dma_segment_t *segs, int nsegments, int error)
{
        struct ida_hardware_qcb *hwqcb = (struct ida_hardware_qcb *)arg;
        int i;

        hwqcb->hdr.size = (sizeof(struct ida_req) + 
            sizeof(struct ida_sgb) * IDA_NSEG) >> 2;

        for (i = 0; i < nsegments; i++) {
                hwqcb->seg[i].addr = segs[i].ds_addr;
                hwqcb->seg[i].length = segs[i].ds_len;
        }
        hwqcb->req.sgcount = nsegments;
}

int
ida_command(struct ida_softc *ida, int command, void *data, int datasize,
        int drive, u_int64_t pblkno, int flags)
{
        struct ida_hardware_qcb *hwqcb;
        struct ida_qcb *qcb;
        bus_dmasync_op_t op;
        int error;

        crit_enter();
        qcb = ida_get_qcb(ida);
        crit_exit();

        if (qcb == NULL) {
                kprintf("ida_command: out of QCBs");
                return (EAGAIN);
        }

        hwqcb = qcb->hwqcb;
        bzero(hwqcb, sizeof(struct ida_hdr) + sizeof(struct ida_req));

        bus_dmamap_load(ida->buffer_dmat, qcb->dmamap,
            data, datasize, ida_setup_dmamap, hwqcb, 0);
        op = qcb->flags & DMA_DATA_IN ?
            BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE;
        bus_dmamap_sync(ida->buffer_dmat, qcb->dmamap, op);

        hwqcb->hdr.drive = drive;
        hwqcb->req.blkno = pblkno;
        hwqcb->req.bcount = howmany(datasize, DEV_BSIZE);
        hwqcb->req.command = command;

        KKASSERT(pblkno < 0x100000000ULL);

        qcb->flags = flags | IDA_COMMAND;

        crit_enter();
        STAILQ_INSERT_TAIL(&ida->qcb_queue, qcb, link.stqe);
        ida_start(ida);
        error = ida_wait(ida, qcb);
        crit_exit();

        /* XXX should have status returned here? */
        /* XXX have "status pointer" area in QCB? */

        return (error);
}

void
ida_submit_buf(struct ida_softc *ida, struct bio *bio)
{
        bioqdisksort(&ida->bio_queue, bio);
        ida_construct_qcb(ida);
        ida_start(ida);
}

static void
ida_construct_qcb(struct ida_softc *ida)
{
        struct ida_hardware_qcb *hwqcb;
        struct ida_qcb *qcb;
        bus_dmasync_op_t op;
        struct buf *bp;
        struct bio *bio;

        bio = bioq_first(&ida->bio_queue);
        if (bio == NULL)
                return;                         /* no more buffers */

        qcb = ida_get_qcb(ida);
        if (qcb == NULL)
                return;                         /* out of resources */

        bioq_remove(&ida->bio_queue, bio);
        qcb->bio = bio;
        qcb->flags = 0;

        hwqcb = qcb->hwqcb;
        bzero(hwqcb, sizeof(struct ida_hdr) + sizeof(struct ida_req));

        bp = bio->bio_buf;
        bus_dmamap_load(ida->buffer_dmat, qcb->dmamap,
            (void *)bp->b_data, bp->b_bcount, ida_setup_dmamap, hwqcb, 0);
        op = qcb->flags & DMA_DATA_IN ?
            BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE;
        bus_dmamap_sync(ida->buffer_dmat, qcb->dmamap, op);

        {
                struct idad_softc *drv;

                drv = (struct idad_softc *)bio->bio_driver_info;
                hwqcb->hdr.drive = drv->drive;
        }

        hwqcb->req.blkno = bio->bio_offset >> DEV_BSHIFT;
        hwqcb->req.bcount = howmany(bp->b_bcount, DEV_BSIZE);
        hwqcb->req.command = (bp->b_cmd == BUF_CMD_READ) ? CMD_READ : CMD_WRITE;

        KKASSERT(bio->bio_offset < 0x100000000ULL * DEV_BSIZE);

        STAILQ_INSERT_TAIL(&ida->qcb_queue, qcb, link.stqe);
}

/*
 * This routine will be called from ida_intr in order to queue up more
 * I/O, meaning that we may be in an interrupt context.  Hence, we should
 * not muck around with spl() in this routine.
 */
static void
ida_start(struct ida_softc *ida)
{
        struct ida_qcb *qcb;

        while ((qcb = STAILQ_FIRST(&ida->qcb_queue)) != NULL) {
                if (ida->cmd.fifo_full(ida))
                        break;
                STAILQ_REMOVE_HEAD(&ida->qcb_queue, link.stqe);
                /*
                 * XXX
                 * place the qcb on an active list and set a timeout?
                 */
                qcb->state = QCB_ACTIVE;
                ida->cmd.submit(ida, qcb);
        }
}

static int
ida_wait(struct ida_softc *ida, struct ida_qcb *qcb)
{
        struct ida_qcb *qcb_done = NULL;
        bus_addr_t completed;
        int delay;

        if (ida->flags & IDA_INTERRUPTS) {
                if (tsleep((caddr_t)qcb, 0, "idacmd", 5 * hz))
                        return (ETIMEDOUT);
                return (0);
        }

again:
        delay = 5 * 1000 * 100;                 /* 5 sec delay */
        while ((completed = ida->cmd.done(ida)) == 0) {
                if (delay-- == 0)
                        return (ETIMEDOUT);
                DELAY(10);
        }

        qcb_done = idahwqcbptov(ida, completed & ~3);
        if (qcb_done != qcb)
                goto again;
        ida_done(ida, qcb);
        return (0);
}

void
ida_intr(void *data)
{
        struct ida_softc *ida;
        struct ida_qcb *qcb;
        bus_addr_t completed;

        ida = (struct ida_softc *)data;

        if (ida->cmd.int_pending(ida) == 0)
                return;                         /* not our interrupt */

        while ((completed = ida->cmd.done(ida)) != 0) {
                qcb = idahwqcbptov(ida, completed & ~3);

                if (qcb == NULL || qcb->state != QCB_ACTIVE) {
                        device_printf(ida->dev,
                            "ignoring completion %jx\n", (uintmax_t)completed);
                        continue;
                }
                ida_done(ida, qcb);
        }
        ida_start(ida);
}

/*
 * should switch out command type; may be status, not just I/O.
 */
static void
ida_done(struct ida_softc *ida, struct ida_qcb *qcb)
{
        int error = 0;

        /*
         * finish up command
         */
        if (qcb->flags & DMA_DATA_TRANSFER) {
                bus_dmasync_op_t op;

                op = qcb->flags & DMA_DATA_IN ?
                    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE;
                bus_dmamap_sync(ida->buffer_dmat, qcb->dmamap, op);
                bus_dmamap_unload(ida->buffer_dmat, qcb->dmamap);
        }

        if (qcb->hwqcb->req.error & SOFT_ERROR)
                device_printf(ida->dev, "soft error\n");
        if (qcb->hwqcb->req.error & HARD_ERROR) {
                error = 1;
                device_printf(ida->dev, "hard error\n");
        }
        if (qcb->hwqcb->req.error & CMD_REJECTED) {
                error = 1;
                device_printf(ida->dev, "invalid request\n");
        }

        if (qcb->flags & IDA_COMMAND) {
                if (ida->flags & IDA_INTERRUPTS)
                        wakeup(qcb);
        } else {
                if (error)
                        qcb->bio->bio_buf->b_flags |= B_ERROR;
                idad_intr(qcb->bio);
        }

        qcb->state = QCB_FREE;
        SLIST_INSERT_HEAD(&ida->free_qcbs, qcb, link.sle);
        ida_construct_qcb(ida);
}