#include <linux/types.h>
#include <linux/mm.h>
#include <linux/blkdev.h>
#include <linux/init.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 <linux/zorro.h>
#include <asm/irq.h>
#include <linux/spinlock.h>

#include "scsi.h"
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#include "a2091.h"

#include<linux/stat.h>

#define DMA(ptr) ((a2091_scsiregs *)((ptr)->base))
#define HDATA(ptr) ((struct WD33C93_hostdata *)((ptr)->hostdata))

static int a2091_release(struct Scsi_Host *instance);

static irqreturn_t a2091_intr (int irq, void *_instance)
{
    unsigned long flags;
    unsigned int status;
    struct Scsi_Host *instance = (struct Scsi_Host *)_instance;

    status = DMA(instance)->ISTR;
    if (!(status & (ISTR_INT_F|ISTR_INT_P)) || !(status & ISTR_INTS))
        return IRQ_NONE;

    spin_lock_irqsave(instance->host_lock, flags);
    wd33c93_intr(instance);
    spin_unlock_irqrestore(instance->host_lock, flags);
    return IRQ_HANDLED;
}

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);
    struct Scsi_Host *instance = cmd->device->host;

    /* don't allow DMA if the physical address is bad */
    if (addr & A2091_XFER_MASK)
    {
        HDATA(instance)->dma_bounce_len = (cmd->SCp.this_residual + 511)
            & ~0x1ff;
        HDATA(instance)->dma_bounce_buffer =
            kmalloc (HDATA(instance)->dma_bounce_len, GFP_KERNEL);
        
        /* can't allocate memory; use PIO */
        if (!HDATA(instance)->dma_bounce_buffer) {
            HDATA(instance)->dma_bounce_len = 0;
            return 1;
        }

        /* get the physical address of the bounce buffer */
        addr = virt_to_bus(HDATA(instance)->dma_bounce_buffer);

        /* the bounce buffer may not be in the first 16M of physmem */
        if (addr & A2091_XFER_MASK) {
            /* we could use chipmem... maybe later */
            kfree (HDATA(instance)->dma_bounce_buffer);
            HDATA(instance)->dma_bounce_buffer = NULL;
            HDATA(instance)->dma_bounce_len = 0;
            return 1;
        }

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

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

    /* remember direction */
    HDATA(cmd->device->host)->dma_dir = dir_in;

    DMA(cmd->device->host)->CNTR = cntr;

    /* setup DMA *physical* address */
    DMA(cmd->device->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 */
    DMA(cmd->device->host)->ST_DMA = 1;

    /* 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;

    /* disable SCSI interrupts */
    DMA(instance)->CNTR = cntr;

    /* flush if we were reading */
    if (HDATA(instance)->dma_dir) {
        DMA(instance)->FLUSH = 1;
        while (!(DMA(instance)->ISTR & ISTR_FE_FLG))
            ;
    }

    /* clear a possible interrupt */
    DMA(instance)->CINT = 1;

    /* stop DMA */
    DMA(instance)->SP_DMA = 1;

    /* restore the CONTROL bits (minus the direction flag) */
    DMA(instance)->CNTR = CNTR_PDMD | CNTR_INTEN;

    /* copy from a bounce buffer, if necessary */
    if (status && HDATA(instance)->dma_bounce_buffer) {
        if( HDATA(instance)->dma_dir )
                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;
    }
}

static int __init a2091_detect(struct scsi_host_template *tpnt)
{
    static unsigned char called = 0;
    struct Scsi_Host *instance;
    unsigned long address;
    struct zorro_dev *z = NULL;
    wd33c93_regs regs;
    int num_a2091 = 0;

    if (!MACH_IS_AMIGA || called)
        return 0;
    called = 1;

    tpnt->proc_name = "A2091";
    tpnt->proc_info = &wd33c93_proc_info;

    while ((z = zorro_find_device(ZORRO_WILDCARD, z))) {
        if (z->id != ZORRO_PROD_CBM_A590_A2091_1 &&
            z->id != ZORRO_PROD_CBM_A590_A2091_2)
            continue;
        address = z->resource.start;
        if (!request_mem_region(address, 256, "wd33c93"))
            continue;

        instance = scsi_register (tpnt, sizeof (struct WD33C93_hostdata));
        if (instance == NULL)
            goto release;
        instance->base = ZTWO_VADDR(address);
        instance->irq = IRQ_AMIGA_PORTS;
        instance->unique_id = z->slotaddr;
        DMA(instance)->DAWR = DAWR_A2091;
        regs.SASR = &(DMA(instance)->SASR);
        regs.SCMD = &(DMA(instance)->SCMD);
        HDATA(instance)->no_sync = 0xff;
        HDATA(instance)->fast = 0;
        HDATA(instance)->dma_mode = CTRL_DMA;
        wd33c93_init(instance, regs, dma_setup, dma_stop, WD33C93_FS_8_10);
        if (request_irq(IRQ_AMIGA_PORTS, a2091_intr, IRQF_SHARED, "A2091 SCSI",
                        instance))
            goto unregister;
        DMA(instance)->CNTR = CNTR_PDMD | CNTR_INTEN;
        num_a2091++;
        continue;

unregister:
        scsi_unregister(instance);
        wd33c93_release();
release:
        release_mem_region(address, 256);
    }

    return num_a2091;
}

static int a2091_bus_reset(struct scsi_cmnd *cmd)
{
        /* FIXME perform bus-specific reset */

        /* FIXME 2: kill this function, and let midlayer fall back
           to the same action, calling wd33c93_host_reset() */

        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              = "A2901",
        .name                   = "Commodore A2091/A590 SCSI",
        .detect                 = a2091_detect,
        .release                = a2091_release,
        .queuecommand           = wd33c93_queuecommand,
        .eh_abort_handler       = wd33c93_abort,
        .eh_bus_reset_handler   = a2091_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         = DISABLE_CLUSTERING
};


#include "scsi_module.c"

static int a2091_release(struct Scsi_Host *instance)
{
#ifdef MODULE
        DMA(instance)->CNTR = 0;
        release_mem_region(ZTWO_PADDR(instance->base), 256);
        free_irq(IRQ_AMIGA_PORTS, instance);
        wd33c93_release();
#endif
        return 1;
}

MODULE_LICENSE("GPL");