#include <linux/types.h>
#include <linux/mm.h>
#include <linux/blkdev.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>

#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>
#include <asm/irq.h>

#include "scsi.h"
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#include "a3000.h"

#include<linux/stat.h>

#define DMA(ptr) ((a3000_scsiregs *)((ptr)->base))
#define HDATA(ptr) ((struct WD33C93_hostdata *)((ptr)->hostdata))

static struct Scsi_Host *a3000_host = NULL;

static irqreturn_t a3000_intr (int irq, void *dummy)
{
        unsigned long flags;
        unsigned int status = DMA(a3000_host)->ISTR;

        if (!(status & ISTR_INT_P))
                return IRQ_NONE;
        if (status & ISTR_INTS)
        {
                spin_lock_irqsave(a3000_host->host_lock, flags);
                wd33c93_intr (a3000_host);
                spin_unlock_irqrestore(a3000_host->host_lock, flags);
                return IRQ_HANDLED;
        }
        printk("Non-serviced A3000 SCSI-interrupt? ISTR = %02x\n", status);
        return IRQ_NONE;
}

static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
{
    unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
    unsigned long addr = virt_to_bus(cmd->SCp.ptr);

    /*
     * if the physical address has the wrong alignment, or if
     * physical address is bad, or if it is a write and at the
     * end of a physical memory chunk, then allocate a bounce
     * buffer
     */
    if (addr & A3000_XFER_MASK ||
        (!dir_in && mm_end_of_chunk (addr, cmd->SCp.this_residual)))
    {
        HDATA(a3000_host)->dma_bounce_len = (cmd->SCp.this_residual + 511)
            & ~0x1ff;
        HDATA(a3000_host)->dma_bounce_buffer =
            kmalloc (HDATA(a3000_host)->dma_bounce_len, GFP_KERNEL);
        
        /* can't allocate memory; use PIO */
        if (!HDATA(a3000_host)->dma_bounce_buffer) {
            HDATA(a3000_host)->dma_bounce_len = 0;
            return 1;
        }

        if (!dir_in) {
            /* copy to bounce buffer for a write */
            if (cmd->use_sg) {
                memcpy (HDATA(a3000_host)->dma_bounce_buffer,
                        cmd->SCp.ptr, cmd->SCp.this_residual);
            } else
                memcpy (HDATA(a3000_host)->dma_bounce_buffer,
                        cmd->request_buffer, cmd->request_bufflen);
        }

        addr = virt_to_bus(HDATA(a3000_host)->dma_bounce_buffer);
    }

    /* setup dma direction */
    if (!dir_in)
        cntr |= CNTR_DDIR;

    /* remember direction */
    HDATA(a3000_host)->dma_dir = dir_in;

    DMA(a3000_host)->CNTR = cntr;

    /* setup DMA *physical* address */
    DMA(a3000_host)->ACR = addr;

    if (dir_in)
        /* invalidate any cache */
        cache_clear (addr, cmd->SCp.this_residual);
    else
        /* push any dirty cache */
        cache_push (addr, cmd->SCp.this_residual);

    /* start DMA */
    mb();                       /* make sure setup is completed */
    DMA(a3000_host)->ST_DMA = 1;
    mb();                       /* make sure DMA has started before next IO */

    /* return success */
    return 0;
}

static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
                     int status)
{
    /* disable SCSI interrupts */
    unsigned short cntr = CNTR_PDMD;

    if (!HDATA(instance)->dma_dir)
        cntr |= CNTR_DDIR;

    DMA(instance)->CNTR = cntr;
    mb();                       /* make sure CNTR is updated before next IO */

    /* flush if we were reading */
    if (HDATA(instance)->dma_dir) {
        DMA(instance)->FLUSH = 1;
        mb();                   /* don't allow prefetch */
        while (!(DMA(instance)->ISTR & ISTR_FE_FLG))
            barrier();
        mb();                   /* no IO until FLUSH is done */
    }

    /* clear a possible interrupt */
    /* I think that this CINT is only necessary if you are
     * using the terminal count features.   HM 7 Mar 1994
     */
    DMA(instance)->CINT = 1;

    /* stop DMA */
    DMA(instance)->SP_DMA = 1;
    mb();                       /* make sure DMA is stopped before next IO */

    /* restore the CONTROL bits (minus the direction flag) */
    DMA(instance)->CNTR = CNTR_PDMD | CNTR_INTEN;
    mb();                       /* make sure CNTR is updated before next IO */

    /* copy from a bounce buffer, if necessary */
    if (status && HDATA(instance)->dma_bounce_buffer) {
        if (SCpnt && SCpnt->use_sg) {
            if (HDATA(instance)->dma_dir && SCpnt)
                memcpy (SCpnt->SCp.ptr,
                        HDATA(instance)->dma_bounce_buffer,
                        SCpnt->SCp.this_residual);
            kfree (HDATA(instance)->dma_bounce_buffer);
            HDATA(instance)->dma_bounce_buffer = NULL;
            HDATA(instance)->dma_bounce_len = 0;
        } else {
            if (HDATA(instance)->dma_dir && SCpnt)
                memcpy (SCpnt->request_buffer,
                        HDATA(instance)->dma_bounce_buffer,
                        SCpnt->request_bufflen);

            kfree (HDATA(instance)->dma_bounce_buffer);
            HDATA(instance)->dma_bounce_buffer = NULL;
            HDATA(instance)->dma_bounce_len = 0;
        }
    }
}

int __init a3000_detect(struct scsi_host_template *tpnt)
{
    wd33c93_regs regs;

    if  (!MACH_IS_AMIGA || !AMIGAHW_PRESENT(A3000_SCSI))
        return 0;
    if (!request_mem_region(0xDD0000, 256, "wd33c93"))
        return 0;

    tpnt->proc_name = "A3000";
    tpnt->proc_info = &wd33c93_proc_info;

    a3000_host = scsi_register (tpnt, sizeof(struct WD33C93_hostdata));
    if (a3000_host == NULL)
        goto fail_register;

    a3000_host->base = ZTWO_VADDR(0xDD0000);
    a3000_host->irq = IRQ_AMIGA_PORTS;
    DMA(a3000_host)->DAWR = DAWR_A3000;
    regs.SASR = &(DMA(a3000_host)->SASR);
    regs.SCMD = &(DMA(a3000_host)->SCMD);
    wd33c93_init(a3000_host, regs, dma_setup, dma_stop, WD33C93_FS_12_15);
    if (request_irq(IRQ_AMIGA_PORTS, a3000_intr, IRQF_SHARED, "A3000 SCSI",
                    a3000_intr))
        goto fail_irq;
    DMA(a3000_host)->CNTR = CNTR_PDMD | CNTR_INTEN;

    return 1;

fail_irq:
    wd33c93_release();
    scsi_unregister(a3000_host);
fail_register:
    release_mem_region(0xDD0000, 256);
    return 0;
}

static int a3000_bus_reset(struct scsi_cmnd *cmd)
{
        /* FIXME perform bus-specific reset */
        
        /* FIXME 2: kill this entire function, which should
           cause mid-layer to call wd33c93_host_reset anyway? */

        spin_lock_irq(cmd->device->host->host_lock);
        wd33c93_host_reset(cmd);
        spin_unlock_irq(cmd->device->host->host_lock);

        return SUCCESS;
}

#define HOSTS_C

static struct scsi_host_template driver_template = {
        .proc_name              = "A3000",
        .name                   = "Amiga 3000 built-in SCSI",
        .detect                 = a3000_detect,
        .release                = a3000_release,
        .queuecommand           = wd33c93_queuecommand,
        .eh_abort_handler       = wd33c93_abort,
        .eh_bus_reset_handler   = a3000_bus_reset,
        .eh_host_reset_handler  = wd33c93_host_reset,
        .can_queue              = CAN_QUEUE,
        .this_id                = 7,
        .sg_tablesize           = SG_ALL,
        .cmd_per_lun            = CMD_PER_LUN,
        .use_clustering         = ENABLE_CLUSTERING
};


#include "scsi_module.c"

int a3000_release(struct Scsi_Host *instance)
{
    wd33c93_release();
    DMA(instance)->CNTR = 0;
    release_mem_region(0xDD0000, 256);
    free_irq(IRQ_AMIGA_PORTS, a3000_intr);
    return 1;
}

MODULE_LICENSE("GPL");