#include <linux/types.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/mm.h>
  #include <linux/slab.h>
  #include <linux/spinlock.h>
  #include <linux/zorro.h>
  #include <linux/module.h>
  
  #include <asm/page.h>
  #include <asm/pgtable.h>
  #include <asm/amigaints.h>
  #include <asm/amigahw.h>
  
  #include "scsi.h"
  #include "wd33c93.h"
  #include "a2091.h"
  
  
  struct a2091_hostdata {
  	struct WD33C93_hostdata wh;
  	struct a2091_scsiregs *regs;
  };
  
  static irqreturn_t a2091_intr(int irq, void *data)
  {
  	struct Scsi_Host *instance = data;
  	struct a2091_hostdata *hdata = shost_priv(instance);
  	unsigned int status = hdata->regs->ISTR;
  	unsigned long flags;
  
  	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)
  {
  	struct Scsi_Host *instance = cmd->device->host;
  	struct a2091_hostdata *hdata = shost_priv(instance);
  	struct WD33C93_hostdata *wh = &hdata->wh;
  	struct a2091_scsiregs *regs = hdata->regs;
  	unsigned short cntr = CNTR_PDMD | CNTR_INTEN;
  	unsigned long addr = virt_to_bus(cmd->SCp.ptr);
  
  	/* don't allow DMA if the physical address is bad */
  	if (addr & A2091_XFER_MASK) {
  		wh->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
  		wh->dma_bounce_buffer = kmalloc(wh->dma_bounce_len,
  						GFP_KERNEL);
  
  		/* can't allocate memory; use PIO */
  		if (!wh->dma_bounce_buffer) {
  			wh->dma_bounce_len = 0;
  			return 1;
  		}
  
  		/* get the physical address of the bounce buffer */
  		addr = virt_to_bus(wh->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(wh->dma_bounce_buffer);
  			wh->dma_bounce_buffer = NULL;
  			wh->dma_bounce_len = 0;
  			return 1;
  		}
  
  		if (!dir_in) {
  			/* copy to bounce buffer for a write */
  			memcpy(wh->dma_bounce_buffer, cmd->SCp.ptr,
  			       cmd->SCp.this_residual);
  		}
  	}
  
  	/* setup dma direction */
  	if (!dir_in)
  		cntr |= CNTR_DDIR;
  
  	/* remember direction */
  	wh->dma_dir = dir_in;
  
  	regs->CNTR = cntr;
  
  	/* setup DMA *physical* address */
  	regs->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 */
  	regs->ST_DMA = 1;
  
  	/* return success */
  	return 0;
  }
  
  static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
  		     int status)
  {
  	struct a2091_hostdata *hdata = shost_priv(instance);
  	struct WD33C93_hostdata *wh = &hdata->wh;
  	struct a2091_scsiregs *regs = hdata->regs;
  
  	/* disable SCSI interrupts */
  	unsigned short cntr = CNTR_PDMD;
  
  	if (!wh->dma_dir)
  		cntr |= CNTR_DDIR;
  
  	/* disable SCSI interrupts */
  	regs->CNTR = cntr;
  
  	/* flush if we were reading */
  	if (wh->dma_dir) {
  		regs->FLUSH = 1;
  		while (!(regs->ISTR & ISTR_FE_FLG))
  			;
  	}
  
  	/* clear a possible interrupt */
  	regs->CINT = 1;
  
  	/* stop DMA */
  	regs->SP_DMA = 1;
  
  	/* restore the CONTROL bits (minus the direction flag) */
  	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
  
  	/* copy from a bounce buffer, if necessary */
  	if (status && wh->dma_bounce_buffer) {
  		if (wh->dma_dir)
  			memcpy(SCpnt->SCp.ptr, wh->dma_bounce_buffer,
  			       SCpnt->SCp.this_residual);
  		kfree(wh->dma_bounce_buffer);
  		wh->dma_bounce_buffer = NULL;
  		wh->dma_bounce_len = 0;
  	}
  }
  
  static int a2091_bus_reset(struct scsi_cmnd *cmd)
  {
  	struct Scsi_Host *instance = cmd->device->host;
  
  	/* 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(instance->host_lock);
  	wd33c93_host_reset(cmd);
  	spin_unlock_irq(instance->host_lock);
  
  	return SUCCESS;
  }
  
  static struct scsi_host_template a2091_scsi_template = {
  	.module			= THIS_MODULE,
  	.name			= "Commodore A2091/A590 SCSI",
  	.show_info		= wd33c93_show_info,
  	.write_info		= wd33c93_write_info,
  	.proc_name		= "A2901",
  	.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
  };
  
  static int a2091_probe(struct zorro_dev *z, const struct zorro_device_id *ent)
  {
  	struct Scsi_Host *instance;
  	int error;
  	struct a2091_scsiregs *regs;
  	wd33c93_regs wdregs;
  	struct a2091_hostdata *hdata;
  
  	if (!request_mem_region(z->resource.start, 256, "wd33c93"))
  		return -EBUSY;
  
  	instance = scsi_host_alloc(&a2091_scsi_template,
  				   sizeof(struct a2091_hostdata));
  	if (!instance) {
  		error = -ENOMEM;
  		goto fail_alloc;
  	}
  
  	instance->irq = IRQ_AMIGA_PORTS;
  	instance->unique_id = z->slotaddr;
  
  	regs = ZTWO_VADDR(z->resource.start);
  	regs->DAWR = DAWR_A2091;
  
  	wdregs.SASR = &regs->SASR;
  	wdregs.SCMD = &regs->SCMD;
  
  	hdata = shost_priv(instance);
  	hdata->wh.no_sync = 0xff;
  	hdata->wh.fast = 0;
  	hdata->wh.dma_mode = CTRL_DMA;
  	hdata->regs = regs;
  
  	wd33c93_init(instance, wdregs, dma_setup, dma_stop, WD33C93_FS_8_10);
  	error = request_irq(IRQ_AMIGA_PORTS, a2091_intr, IRQF_SHARED,
  			    "A2091 SCSI", instance);
  	if (error)
  		goto fail_irq;
  
  	regs->CNTR = CNTR_PDMD | CNTR_INTEN;
  
  	error = scsi_add_host(instance, NULL);
  	if (error)
  		goto fail_host;
  
  	zorro_set_drvdata(z, instance);
  
  	scsi_scan_host(instance);
  	return 0;
  
  fail_host:
  	free_irq(IRQ_AMIGA_PORTS, instance);
  fail_irq:
  	scsi_host_put(instance);
  fail_alloc:
  	release_mem_region(z->resource.start, 256);
  	return error;
  }
  
  static void a2091_remove(struct zorro_dev *z)
  {
  	struct Scsi_Host *instance = zorro_get_drvdata(z);
  	struct a2091_hostdata *hdata = shost_priv(instance);
  
  	hdata->regs->CNTR = 0;
  	scsi_remove_host(instance);
  	free_irq(IRQ_AMIGA_PORTS, instance);
  	scsi_host_put(instance);
  	release_mem_region(z->resource.start, 256);
  }
  
  static struct zorro_device_id a2091_zorro_tbl[] = {
  	{ ZORRO_PROD_CBM_A590_A2091_1 },
  	{ ZORRO_PROD_CBM_A590_A2091_2 },
  	{ 0 }
  };
  MODULE_DEVICE_TABLE(zorro, a2091_zorro_tbl);
  
  static struct zorro_driver a2091_driver = {
  	.name		= "a2091",
  	.id_table	= a2091_zorro_tbl,
  	.probe		= a2091_probe,
  	.remove		= a2091_remove,
  };
  
  static int __init a2091_init(void)
  {
  	return zorro_register_driver(&a2091_driver);
  }
  module_init(a2091_init);
  
  static void __exit a2091_exit(void)
  {
  	zorro_unregister_driver(&a2091_driver);
  }
  module_exit(a2091_exit);
  
  MODULE_DESCRIPTION("Commodore A2091/A590 SCSI");
  MODULE_LICENSE("GPL");