#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 "gvp11.h"

#include<linux/stat.h>

#define DMA(ptr) ((gvp11_scsiregs *)((ptr)->base))
#define HDATA(ptr) ((struct WD33C93_hostdata *)((ptr)->hostdata))

static irqreturn_t gvp11_intr (int irq, void *_instance)
{
    unsigned long flags;
    unsigned int status;
    struct Scsi_Host *instance = (struct Scsi_Host *)_instance;

    status = DMA(instance)->CNTR;
    if (!(status & GVP11_DMAC_INT_PENDING))
        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 gvp11_xfer_mask = 0;

void gvp11_setup (char *str, int *ints)
{
    gvp11_xfer_mask = ints[1];
}

static int dma_setup(struct scsi_cmnd *cmd, int dir_in)
{
    unsigned short cntr = GVP11_DMAC_INT_ENABLE;
    unsigned long addr = virt_to_bus(cmd->SCp.ptr);
    int bank_mask;
    static int scsi_alloc_out_of_range = 0;

    /* use bounce buffer if the physical address is bad */
    if (addr & HDATA(cmd->device->host)->dma_xfer_mask)
    {
        HDATA(cmd->device->host)->dma_bounce_len = (cmd->SCp.this_residual + 511)
            & ~0x1ff;

        if( !scsi_alloc_out_of_range ) {
            HDATA(cmd->device->host)->dma_bounce_buffer =
                kmalloc (HDATA(cmd->device->host)->dma_bounce_len, GFP_KERNEL);
            HDATA(cmd->device->host)->dma_buffer_pool = BUF_SCSI_ALLOCED;
        }

        if (scsi_alloc_out_of_range ||
            !HDATA(cmd->device->host)->dma_bounce_buffer) {
            HDATA(cmd->device->host)->dma_bounce_buffer =
                amiga_chip_alloc(HDATA(cmd->device->host)->dma_bounce_len,
                                       "GVP II SCSI Bounce Buffer");

            if(!HDATA(cmd->device->host)->dma_bounce_buffer)
            {
                HDATA(cmd->device->host)->dma_bounce_len = 0;
                return 1;
            }

            HDATA(cmd->device->host)->dma_buffer_pool = BUF_CHIP_ALLOCED;
        }

        /* check if the address of the bounce buffer is OK */
        addr = virt_to_bus(HDATA(cmd->device->host)->dma_bounce_buffer);

        if (addr & HDATA(cmd->device->host)->dma_xfer_mask) {
            /* fall back to Chip RAM if address out of range */
            if( HDATA(cmd->device->host)->dma_buffer_pool == BUF_SCSI_ALLOCED) {
                kfree (HDATA(cmd->device->host)->dma_bounce_buffer);
                scsi_alloc_out_of_range = 1;
            } else {
                amiga_chip_free (HDATA(cmd->device->host)->dma_bounce_buffer);
            }
                
            HDATA(cmd->device->host)->dma_bounce_buffer =
                amiga_chip_alloc(HDATA(cmd->device->host)->dma_bounce_len,
                                       "GVP II SCSI Bounce Buffer");

            if(!HDATA(cmd->device->host)->dma_bounce_buffer)
            {
                HDATA(cmd->device->host)->dma_bounce_len = 0;
                return 1;
            }

            addr = virt_to_bus(HDATA(cmd->device->host)->dma_bounce_buffer);
            HDATA(cmd->device->host)->dma_buffer_pool = BUF_CHIP_ALLOCED;
        }
            
        if (!dir_in) {
            /* copy to bounce buffer for a write */
            memcpy (HDATA(cmd->device->host)->dma_bounce_buffer,
                    cmd->SCp.ptr, cmd->SCp.this_residual);
        }
    }

    /* setup dma direction */
    if (!dir_in)
        cntr |= GVP11_DMAC_DIR_WRITE;

    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);

    if ((bank_mask = (~HDATA(cmd->device->host)->dma_xfer_mask >> 18) & 0x01c0))
            DMA(cmd->device->host)->BANK = bank_mask & (addr >> 18);

    /* 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)
{
    /* stop DMA */
    DMA(instance)->SP_DMA = 1;
    /* remove write bit from CONTROL bits */
    DMA(instance)->CNTR = GVP11_DMAC_INT_ENABLE;

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

#define CHECK_WD33C93

int __init gvp11_detect(struct scsi_host_template *tpnt)
{
    static unsigned char called = 0;
    struct Scsi_Host *instance;
    unsigned long address;
    unsigned int epc;
    struct zorro_dev *z = NULL;
    unsigned int default_dma_xfer_mask;
    wd33c93_regs regs;
    int num_gvp11 = 0;
#ifdef CHECK_WD33C93
    volatile unsigned char *sasr_3393, *scmd_3393;
    unsigned char save_sasr;
    unsigned char q, qq;
#endif

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

    tpnt->proc_name = "GVP11";
    tpnt->proc_info = &wd33c93_proc_info;

    while ((z = zorro_find_device(ZORRO_WILDCARD, z))) {
        /* 
         * This should (hopefully) be the correct way to identify
         * all the different GVP SCSI controllers (except for the
         * SERIES I though).
         */

        if (z->id == ZORRO_PROD_GVP_COMBO_030_R3_SCSI ||
            z->id == ZORRO_PROD_GVP_SERIES_II)
            default_dma_xfer_mask = ~0x00ffffff;
        else if (z->id == ZORRO_PROD_GVP_GFORCE_030_SCSI ||
                 z->id == ZORRO_PROD_GVP_A530_SCSI ||
                 z->id == ZORRO_PROD_GVP_COMBO_030_R4_SCSI)
            default_dma_xfer_mask = ~0x01ffffff;
        else if (z->id == ZORRO_PROD_GVP_A1291 ||
                 z->id == ZORRO_PROD_GVP_GFORCE_040_SCSI_1)
            default_dma_xfer_mask = ~0x07ffffff;
        else
            continue;

        /*
         * Rumors state that some GVP ram boards use the same product
         * code as the SCSI controllers. Therefore if the board-size
         * is not 64KB we asume it is a ram board and bail out.
         */
        if (z->resource.end-z->resource.start != 0xffff)
                continue;

        address = z->resource.start;
        if (!request_mem_region(address, 256, "wd33c93"))
            continue;

#ifdef CHECK_WD33C93

        /*
         * These darn GVP boards are a problem - it can be tough to tell
         * whether or not they include a SCSI controller. This is the
         * ultimate Yet-Another-GVP-Detection-Hack in that it actually
         * probes for a WD33c93 chip: If we find one, it's extremely
         * likely that this card supports SCSI, regardless of Product_
         * Code, Board_Size, etc. 
         */

    /* Get pointers to the presumed register locations and save contents */

        sasr_3393 = &(((gvp11_scsiregs *)(ZTWO_VADDR(address)))->SASR);
        scmd_3393 = &(((gvp11_scsiregs *)(ZTWO_VADDR(address)))->SCMD);
        save_sasr = *sasr_3393;

    /* First test the AuxStatus Reg */

        q = *sasr_3393;         /* read it */
        if (q & 0x08)           /* bit 3 should always be clear */
                goto release;
        *sasr_3393 = WD_AUXILIARY_STATUS;        /* setup indirect address */
        if (*sasr_3393 == WD_AUXILIARY_STATUS) { /* shouldn't retain the write */
                *sasr_3393 = save_sasr; /* Oops - restore this byte */
                goto release;
                }
        if (*sasr_3393 != q) {  /* should still read the same */
                *sasr_3393 = save_sasr; /* Oops - restore this byte */
                goto release;
                }
        if (*scmd_3393 != q)    /* and so should the image at 0x1f */
                goto release;


    /* Ok, we probably have a wd33c93, but let's check a few other places
     * for good measure. Make sure that this works for both 'A and 'B    
     * chip versions.
     */

        *sasr_3393 = WD_SCSI_STATUS;
        q = *scmd_3393;
        *sasr_3393 = WD_SCSI_STATUS;
        *scmd_3393 = ~q;
        *sasr_3393 = WD_SCSI_STATUS;
        qq = *scmd_3393;
        *sasr_3393 = WD_SCSI_STATUS;
        *scmd_3393 = q;
        if (qq != q)                    /* should be read only */
                goto release;
        *sasr_3393 = 0x1e;      /* this register is unimplemented */
        q = *scmd_3393;
        *sasr_3393 = 0x1e;
        *scmd_3393 = ~q;
        *sasr_3393 = 0x1e;
        qq = *scmd_3393;
        *sasr_3393 = 0x1e;
        *scmd_3393 = q;
        if (qq != q || qq != 0xff)      /* should be read only, all 1's */
                goto release;
        *sasr_3393 = WD_TIMEOUT_PERIOD;
        q = *scmd_3393;
        *sasr_3393 = WD_TIMEOUT_PERIOD;
        *scmd_3393 = ~q;
        *sasr_3393 = WD_TIMEOUT_PERIOD;
        qq = *scmd_3393;
        *sasr_3393 = WD_TIMEOUT_PERIOD;
        *scmd_3393 = q;
        if (qq != (~q & 0xff))          /* should be read/write */
                goto release;
#endif

        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;

        if (gvp11_xfer_mask)
                HDATA(instance)->dma_xfer_mask = gvp11_xfer_mask;
        else
                HDATA(instance)->dma_xfer_mask = default_dma_xfer_mask;


        DMA(instance)->secret2 = 1;
        DMA(instance)->secret1 = 0;
        DMA(instance)->secret3 = 15;
        while (DMA(instance)->CNTR & GVP11_DMAC_BUSY) ;
        DMA(instance)->CNTR = 0;

        DMA(instance)->BANK = 0;

        epc = *(unsigned short *)(ZTWO_VADDR(address) + 0x8000);

        /*
         * Check for 14MHz SCSI clock
         */
        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,
                     (epc & GVP_SCSICLKMASK) ? WD33C93_FS_8_10
                                             : WD33C93_FS_12_15);

        if (request_irq(IRQ_AMIGA_PORTS, gvp11_intr, IRQF_SHARED, "GVP11 SCSI",
                        instance))
                goto unregister;
        DMA(instance)->CNTR = GVP11_DMAC_INT_ENABLE;
        num_gvp11++;
        continue;

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

    return num_gvp11;
}

static int gvp11_bus_reset(struct scsi_cmnd *cmd)
{
        /* FIXME perform bus-specific reset */

        /* FIXME 2: shouldn't we no-op this function (return
           FAILED), and fall back to host reset function,
           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

#include "gvp11.h"

static struct scsi_host_template driver_template = {
        .proc_name              = "GVP11",
        .name                   = "GVP Series II SCSI",
        .detect                 = gvp11_detect,
        .release                = gvp11_release,
        .queuecommand           = wd33c93_queuecommand,
        .eh_abort_handler       = wd33c93_abort,
        .eh_bus_reset_handler   = gvp11_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"

int gvp11_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");