#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.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))

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)
{
	struct Scsi_Host *instance = cmd->device->host;
	struct WD33C93_hostdata *hdata = shost_priv(instance);
	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) {
		hdata->dma_bounce_len = (cmd->SCp.this_residual + 511) & ~0x1ff;
		hdata->dma_bounce_buffer = kmalloc(hdata->dma_bounce_len,
						   GFP_KERNEL);

		/* can't allocate memory; use PIO */
		if (!hdata->dma_bounce_buffer) {
			hdata->dma_bounce_len = 0;
			return 1;
		}

		/* get the physical address of the bounce buffer */
		addr = virt_to_bus(hdata->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->dma_bounce_buffer);
			hdata->dma_bounce_buffer = NULL;
			hdata->dma_bounce_len = 0;
			return 1;
		}

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

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

	/* remember direction */
	hdata->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)
{
	struct WD33C93_hostdata *hdata = shost_priv(instance);

	/* disable SCSI interrupts */
	unsigned short cntr = CNTR_PDMD;

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

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

	/* flush if we were reading */
	if (hdata->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->dma_bounce_buffer) {
		if (hdata->dma_dir)
			memcpy(SCpnt->SCp.ptr, hdata->dma_bounce_buffer,
			       SCpnt->SCp.this_residual);
		kfree(hdata->dma_bounce_buffer);
		hdata->dma_bounce_buffer = NULL;
		hdata->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;
	struct WD33C93_hostdata *hdata;
	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 = shost_priv(instance);
		hdata->no_sync = 0xff;
		hdata->fast = 0;
		hdata->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);
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);
#endif
	return 1;
}

MODULE_LICENSE("GPL");