#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 "gvp11.h"
  
  
  #define CHECK_WD33C93
  
  struct gvp11_hostdata {
  	struct WD33C93_hostdata wh;
  	struct gvp11_scsiregs *regs;
  };
  
  static irqreturn_t gvp11_intr(int irq, void *data)
  {
  	struct Scsi_Host *instance = data;
  	struct gvp11_hostdata *hdata = shost_priv(instance);
  	unsigned int status = hdata->regs->CNTR;
  	unsigned long flags;
  
  	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)
  {
  	struct Scsi_Host *instance = cmd->device->host;
  	struct gvp11_hostdata *hdata = shost_priv(instance);
  	struct WD33C93_hostdata *wh = &hdata->wh;
  	struct gvp11_scsiregs *regs = hdata->regs;
  	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 & wh->dma_xfer_mask) {
  		wh->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
  
  		if (!scsi_alloc_out_of_range) {
  			wh->dma_bounce_buffer =
  				kmalloc(wh->dma_bounce_len, GFP_KERNEL);
  			wh->dma_buffer_pool = BUF_SCSI_ALLOCED;
  		}
  
  		if (scsi_alloc_out_of_range ||
  		    !wh->dma_bounce_buffer) {
  			wh->dma_bounce_buffer =
  				amiga_chip_alloc(wh->dma_bounce_len,
  						 "GVP II SCSI Bounce Buffer");
  
  			if (!wh->dma_bounce_buffer) {
  				wh->dma_bounce_len = 0;
  				return 1;
  			}
  
  			wh->dma_buffer_pool = BUF_CHIP_ALLOCED;
  		}
  
  		/* check if the address of the bounce buffer is OK */
  		addr = virt_to_bus(wh->dma_bounce_buffer);
  
  		if (addr & wh->dma_xfer_mask) {
  			/* fall back to Chip RAM if address out of range */
  			if (wh->dma_buffer_pool == BUF_SCSI_ALLOCED) {
  				kfree(wh->dma_bounce_buffer);
  				scsi_alloc_out_of_range = 1;
  			} else {
  				amiga_chip_free(wh->dma_bounce_buffer);
  			}
  
  			wh->dma_bounce_buffer =
  				amiga_chip_alloc(wh->dma_bounce_len,
  						 "GVP II SCSI Bounce Buffer");
  
  			if (!wh->dma_bounce_buffer) {
  				wh->dma_bounce_len = 0;
  				return 1;
  			}
  
  			addr = virt_to_bus(wh->dma_bounce_buffer);
  			wh->dma_buffer_pool = BUF_CHIP_ALLOCED;
  		}
  
  		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 |= GVP11_DMAC_DIR_WRITE;
  
  	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);
  	}
  
  	bank_mask = (~wh->dma_xfer_mask >> 18) & 0x01c0;
  	if (bank_mask)
  		regs->BANK = bank_mask & (addr >> 18);
  
  	/* 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 gvp11_hostdata *hdata = shost_priv(instance);
  	struct WD33C93_hostdata *wh = &hdata->wh;
  	struct gvp11_scsiregs *regs = hdata->regs;
  
  	/* stop DMA */
  	regs->SP_DMA = 1;
  	/* remove write bit from CONTROL bits */
  	regs->CNTR = GVP11_DMAC_INT_ENABLE;
  
  	/* copy from a bounce buffer, if necessary */
  	if (status && wh->dma_bounce_buffer) {
  		if (wh->dma_dir && SCpnt)
  			memcpy(SCpnt->SCp.ptr, wh->dma_bounce_buffer,
  			       SCpnt->SCp.this_residual);
  
  		if (wh->dma_buffer_pool == BUF_SCSI_ALLOCED)
  			kfree(wh->dma_bounce_buffer);
  		else
  			amiga_chip_free(wh->dma_bounce_buffer);
  
  		wh->dma_bounce_buffer = NULL;
  		wh->dma_bounce_len = 0;
  	}
  }
  
  static int gvp11_bus_reset(struct scsi_cmnd *cmd)
  {
  	struct Scsi_Host *instance = cmd->device->host;
  
  	/* 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(instance->host_lock);
  	wd33c93_host_reset(cmd);
  	spin_unlock_irq(instance->host_lock);
  
  	return SUCCESS;
  }
  
  static struct scsi_host_template gvp11_scsi_template = {
  	.module			= THIS_MODULE,
  	.name			= "GVP Series II SCSI",
  	.show_info		= wd33c93_show_info,
  	.write_info		= wd33c93_write_info,
  	.proc_name		= "GVP11",
  	.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
  };
  
  static int check_wd33c93(struct gvp11_scsiregs *regs)
  {
  #ifdef CHECK_WD33C93
  	volatile unsigned char *sasr_3393, *scmd_3393;
  	unsigned char save_sasr;
  	unsigned char q, qq;
  
  	/*
  	 * 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 = &regs->SASR;
  	scmd_3393 = &regs->SCMD;
  	save_sasr = *sasr_3393;
  
  	/* First test the AuxStatus Reg */
  
  	q = *sasr_3393;	/* read it */
  	if (q & 0x08)	/* bit 3 should always be clear */
  		return -ENODEV;
  	*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 */
  		return -ENODEV;
  	}
  	if (*sasr_3393 != q) {	/* should still read the same */
  		*sasr_3393 = save_sasr;	/* Oops - restore this byte */
  		return -ENODEV;
  	}
  	if (*scmd_3393 != q)	/* and so should the image at 0x1f */
  		return -ENODEV;
  
  	/*
  	 * 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 */
  		return -ENODEV;
  	*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 */
  		return -ENODEV;
  	*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 */
  		return -ENODEV;
  #endif /* CHECK_WD33C93 */
  
  	return 0;
  }
  
  static int gvp11_probe(struct zorro_dev *z, const struct zorro_device_id *ent)
  {
  	struct Scsi_Host *instance;
  	unsigned long address;
  	int error;
  	unsigned int epc;
  	unsigned int default_dma_xfer_mask;
  	struct gvp11_hostdata *hdata;
  	struct gvp11_scsiregs *regs;
  	wd33c93_regs wdregs;
  
  	default_dma_xfer_mask = ent->driver_data;
  
  	/*
  	 * 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 assume it is a ram board and bail out.
  	 */
  	if (zorro_resource_len(z) != 0x10000)
  		return -ENODEV;
  
  	address = z->resource.start;
  	if (!request_mem_region(address, 256, "wd33c93"))
  		return -EBUSY;
  
  	regs = ZTWO_VADDR(address);
  
  	error = check_wd33c93(regs);
  	if (error)
  		goto fail_check_or_alloc;
  
  	instance = scsi_host_alloc(&gvp11_scsi_template,
  				   sizeof(struct gvp11_hostdata));
  	if (!instance) {
  		error = -ENOMEM;
  		goto fail_check_or_alloc;
  	}
  
  	instance->irq = IRQ_AMIGA_PORTS;
  	instance->unique_id = z->slotaddr;
  
  	regs->secret2 = 1;
  	regs->secret1 = 0;
  	regs->secret3 = 15;
  	while (regs->CNTR & GVP11_DMAC_BUSY)
  		;
  	regs->CNTR = 0;
  	regs->BANK = 0;
  
  	wdregs.SASR = &regs->SASR;
  	wdregs.SCMD = &regs->SCMD;
  
  	hdata = shost_priv(instance);
  	if (gvp11_xfer_mask)
  		hdata->wh.dma_xfer_mask = gvp11_xfer_mask;
  	else
  		hdata->wh.dma_xfer_mask = default_dma_xfer_mask;
  
  	hdata->wh.no_sync = 0xff;
  	hdata->wh.fast = 0;
  	hdata->wh.dma_mode = CTRL_DMA;
  	hdata->regs = regs;
  
  	/*
  	 * Check for 14MHz SCSI clock
  	 */
  	epc = *(unsigned short *)(ZTWO_VADDR(address) + 0x8000);
  	wd33c93_init(instance, wdregs, dma_setup, dma_stop,
  		     (epc & GVP_SCSICLKMASK) ? WD33C93_FS_8_10
  					     : WD33C93_FS_12_15);
  
  	error = request_irq(IRQ_AMIGA_PORTS, gvp11_intr, IRQF_SHARED,
  			    "GVP11 SCSI", instance);
  	if (error)
  		goto fail_irq;
  
  	regs->CNTR = GVP11_DMAC_INT_ENABLE;
  
  	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_check_or_alloc:
  	release_mem_region(address, 256);
  	return error;
  }
  
  static void gvp11_remove(struct zorro_dev *z)
  {
  	struct Scsi_Host *instance = zorro_get_drvdata(z);
  	struct gvp11_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);
  }
  
  	/*
  	 * This should (hopefully) be the correct way to identify
  	 * all the different GVP SCSI controllers (except for the
  	 * SERIES I though).
  	 */
  
  static struct zorro_device_id gvp11_zorro_tbl[] = {
  	{ ZORRO_PROD_GVP_COMBO_030_R3_SCSI,	~0x00ffffff },
  	{ ZORRO_PROD_GVP_SERIES_II,		~0x00ffffff },
  	{ ZORRO_PROD_GVP_GFORCE_030_SCSI,	~0x01ffffff },
  	{ ZORRO_PROD_GVP_A530_SCSI,		~0x01ffffff },
  	{ ZORRO_PROD_GVP_COMBO_030_R4_SCSI,	~0x01ffffff },
  	{ ZORRO_PROD_GVP_A1291,			~0x07ffffff },
  	{ ZORRO_PROD_GVP_GFORCE_040_SCSI_1,	~0x07ffffff },
  	{ 0 }
  };
  MODULE_DEVICE_TABLE(zorro, gvp11_zorro_tbl);
  
  static struct zorro_driver gvp11_driver = {
  	.name		= "gvp11",
  	.id_table	= gvp11_zorro_tbl,
  	.probe		= gvp11_probe,
  	.remove		= gvp11_remove,
  };
  
  static int __init gvp11_init(void)
  {
  	return zorro_register_driver(&gvp11_driver);
  }
  module_init(gvp11_init);
  
  static void __exit gvp11_exit(void)
  {
  	zorro_unregister_driver(&gvp11_driver);
  }
  module_exit(gvp11_exit);
  
  MODULE_DESCRIPTION("GVP Series II SCSI");
  MODULE_LICENSE("GPL");