/*
   * Sun3 SCSI stuff by Erik Verbruggen (erik@bigmama.xtdnet.nl)
   *
   * Sun3 DMA routines added by Sam Creasey (sammy@sammy.net)
   *
   * VME support added by Sam Creasey
   *
   * Adapted from sun3_scsi.c -- see there for other headers
   *
   * TODO: modify this driver to support multiple Sun3 SCSI VME boards
   *
   */
  
  #define AUTOSENSE
  
  #include <linux/types.h>
  #include <linux/stddef.h>
  #include <linux/ctype.h>
  #include <linux/delay.h>
  
  #include <linux/module.h>
  #include <linux/signal.h>

  #include <linux/ioport.h>
  #include <linux/init.h>
  #include <linux/blkdev.h>
  
  #include <asm/io.h>
  #include <asm/system.h>
  
  #include <asm/sun3ints.h>
  #include <asm/dvma.h>
  #include <asm/idprom.h>
  #include <asm/machines.h>
  
  #define SUN3_SCSI_VME
  
  #undef SUN3_SCSI_DEBUG
  
  /* dma on! */
  #define REAL_DMA
  
  #include "scsi.h"

  #include "initio.h"

  #include <scsi/scsi_host.h>
  #include "sun3_scsi.h"

  
  extern int sun3_map_test(unsigned long, char *);
  
  #define USE_WRAPPER
  /*#define RESET_BOOT */
  #define DRIVER_SETUP
  
  #define NDEBUG 0
  
  /*
   * BUG can be used to trigger a strange code-size related hang on 2.1 kernels
   */
  #ifdef BUG
  #undef RESET_BOOT
  #undef DRIVER_SETUP
  #endif
  
  /* #define SUPPORT_TAGS */
  
  //#define	ENABLE_IRQ()	enable_irq( SUN3_VEC_VMESCSI0 ); 
  #define ENABLE_IRQ()

  static irqreturn_t scsi_sun3_intr(int irq, void *dummy);

  static inline unsigned char sun3scsi_read(int reg);
  static inline void sun3scsi_write(int reg, int value);
  
  static int setup_can_queue = -1;
  module_param(setup_can_queue, int, 0);
  static int setup_cmd_per_lun = -1;
  module_param(setup_cmd_per_lun, int, 0);
  static int setup_sg_tablesize = -1;
  module_param(setup_sg_tablesize, int, 0);
  #ifdef SUPPORT_TAGS
  static int setup_use_tagged_queuing = -1;
  module_param(setup_use_tagged_queuing, int, 0);
  #endif
  static int setup_hostid = -1;
  module_param(setup_hostid, int, 0);

  static struct scsi_cmnd *sun3_dma_setup_done = NULL;

  
  #define	AFTER_RESET_DELAY	(HZ/2)
  
  /* ms to wait after hitting dma regs */
  #define SUN3_DMA_DELAY 10
  
  /* dvma buffer to allocate -- 32k should hopefully be more than sufficient */
  #define SUN3_DVMA_BUFSIZE 0xe000
  
  /* minimum number of bytes to do dma on */
  #define SUN3_DMA_MINSIZE 128
  
  static volatile unsigned char *sun3_scsi_regp;
  static volatile struct sun3_dma_regs *dregs;
  #ifdef OLDDMA
  static unsigned char *dmabuf = NULL; /* dma memory buffer */
  #endif
  static unsigned char *sun3_dma_orig_addr = NULL;
  static unsigned long sun3_dma_orig_count = 0;
  static int sun3_dma_active = 0;
  static unsigned long last_residual = 0;
  
  /*
   * NCR 5380 register access functions
   */
  
  static inline unsigned char sun3scsi_read(int reg)
  {
  	return( sun3_scsi_regp[reg] );
  }
  
  static inline void sun3scsi_write(int reg, int value)
  {
  	sun3_scsi_regp[reg] = value;
  }
  
  /*
   * XXX: status debug
   */
  static struct Scsi_Host *default_instance;
  
  /*

   * Function : int sun3scsi_detect(struct scsi_host_template * tpnt)

   *
   * Purpose : initializes mac NCR5380 driver based on the
   *	command line / compile time port and irq definitions.
   *
   * Inputs : tpnt - template for this SCSI adapter.
   *
   * Returns : 1 if a host adapter was found, 0 if not.
   *
   */
   

  static int sun3scsi_detect(struct scsi_host_template * tpnt)

  {
  	unsigned long ioaddr, irq = 0;
  	static int called = 0;
  	struct Scsi_Host *instance;
  	int i;
  	unsigned long addrs[3] = { IOBASE_SUN3_VMESCSI, 
  				   IOBASE_SUN3_VMESCSI + 0x4000,
  				   0 };
  	unsigned long vecs[3] = { SUN3_VEC_VMESCSI0,
  				  SUN3_VEC_VMESCSI1,
  				  0 };
  	/* check that this machine has an onboard 5380 */
  	switch(idprom->id_machtype) {
  	case SM_SUN3|SM_3_160:
  	case SM_SUN3|SM_3_260:
  		break;
  
  	default:
  		return 0;
  	}
  
  	if(called)
  		return 0;
  
  	tpnt->proc_name = "Sun3 5380 VME SCSI";
  
  	/* setup variables */
  	tpnt->can_queue =
  		(setup_can_queue > 0) ? setup_can_queue : CAN_QUEUE;
  	tpnt->cmd_per_lun =
  		(setup_cmd_per_lun > 0) ? setup_cmd_per_lun : CMD_PER_LUN;
  	tpnt->sg_tablesize = 
  		(setup_sg_tablesize >= 0) ? setup_sg_tablesize : SG_TABLESIZE;
  	
  	if (setup_hostid >= 0)
  		tpnt->this_id = setup_hostid;
  	else {
  		/* use 7 as default */
  		tpnt->this_id = 7;
  	}
  	
  	ioaddr = 0;
  	for(i = 0; addrs[i] != 0; i++) {
  		unsigned char x;
  		
  		ioaddr = (unsigned long)sun3_ioremap(addrs[i], PAGE_SIZE,
  						     SUN3_PAGE_TYPE_VME16);
  		irq = vecs[i];
  		sun3_scsi_regp = (unsigned char *)ioaddr;
  		
  		dregs = (struct sun3_dma_regs *)(((unsigned char *)ioaddr) + 8);
  		
  		if(sun3_map_test((unsigned long)dregs, &x)) {
  			unsigned short oldcsr;
  
  			oldcsr = dregs->csr;
  			dregs->csr = 0;
  			udelay(SUN3_DMA_DELAY);
  			if(dregs->csr == 0x1400)
  				break;
  			
  			dregs->csr = oldcsr;
  		}
  
  		iounmap((void *)ioaddr);
  		ioaddr = 0;
  	}
  
  	if(!ioaddr)
  		return 0;
  	
  #ifdef SUPPORT_TAGS
  	if (setup_use_tagged_queuing < 0)
  		setup_use_tagged_queuing = USE_TAGGED_QUEUING;
  #endif
  
  	instance = scsi_register (tpnt, sizeof(struct NCR5380_hostdata));
  	if(instance == NULL)
  		return 0;
  		
  	default_instance = instance;
  
          instance->io_port = (unsigned long) ioaddr;
  	instance->irq = irq;
  
  	NCR5380_init(instance, 0);
  
  	instance->n_io_port = 32;
  
          ((struct NCR5380_hostdata *)instance->hostdata)->ctrl = 0;
  
  	if (request_irq(instance->irq, scsi_sun3_intr,

  			0, "Sun3SCSI-5380VME", instance)) {

  #ifndef REAL_DMA
  		printk("scsi%d: IRQ%d not free, interrupts disabled
  ",
  		       instance->host_no, instance->irq);
  		instance->irq = SCSI_IRQ_NONE;
  #else
  		printk("scsi%d: IRQ%d not free, bailing out
  ",
  		       instance->host_no, instance->irq);
  		return 0;
  #endif
  	}
  
  	printk("scsi%d: Sun3 5380 VME at port %lX irq", instance->host_no, instance->io_port);
  	if (instance->irq == SCSI_IRQ_NONE)
  		printk ("s disabled");
  	else
  		printk (" %d", instance->irq);
  	printk(" options CAN_QUEUE=%d CMD_PER_LUN=%d release=%d",
  	       instance->can_queue, instance->cmd_per_lun,
  	       SUN3SCSI_PUBLIC_RELEASE);
  	printk("
  scsi%d:", instance->host_no);
  	NCR5380_print_options(instance);
  	printk("
  ");
  
  	dregs->csr = 0;
  	udelay(SUN3_DMA_DELAY);
  	dregs->csr = CSR_SCSI | CSR_FIFO | CSR_INTR;
  	udelay(SUN3_DMA_DELAY);
  	dregs->fifo_count = 0;
  	dregs->fifo_count_hi = 0;
  	dregs->dma_addr_hi = 0;
  	dregs->dma_addr_lo = 0;
  	dregs->dma_count_hi = 0;
  	dregs->dma_count_lo = 0;
  
  	dregs->ivect = VME_DATA24 | (instance->irq & 0xff);
  
  	called = 1;
  
  #ifdef RESET_BOOT
  	sun3_scsi_reset_boot(instance);
  #endif
  
  	return 1;
  }
  
  int sun3scsi_release (struct Scsi_Host *shpnt)
  {
  	if (shpnt->irq != SCSI_IRQ_NONE)

  		free_irq(shpnt->irq, shpnt);

  
  	iounmap((void *)sun3_scsi_regp);
  
  	return 0;
  }
  
  #ifdef RESET_BOOT
  /*
   * Our 'bus reset on boot' function
   */
  
  static void sun3_scsi_reset_boot(struct Scsi_Host *instance)
  {
  	unsigned long end;
  
  	NCR5380_local_declare();
  	NCR5380_setup(instance);
  	
  	/*
  	 * Do a SCSI reset to clean up the bus during initialization. No
  	 * messing with the queues, interrupts, or locks necessary here.
  	 */
  
  	printk( "Sun3 SCSI: resetting the SCSI bus..." );
  
  	/* switch off SCSI IRQ - catch an interrupt without IRQ bit set else */
  //       	sun3_disable_irq( IRQ_SUN3_SCSI );
  
  	/* get in phase */
  	NCR5380_write( TARGET_COMMAND_REG,
  		      PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) ));
  
  	/* assert RST */
  	NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST );
  
  	/* The min. reset hold time is 25us, so 40us should be enough */
  	udelay( 50 );
  
  	/* reset RST and interrupt */
  	NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
  	NCR5380_read( RESET_PARITY_INTERRUPT_REG );
  
  	for( end = jiffies + AFTER_RESET_DELAY; time_before(jiffies, end); )
  		barrier();
  
  	/* switch on SCSI IRQ again */
  //       	sun3_enable_irq( IRQ_SUN3_SCSI );
  
  	printk( " done
  " );
  }
  #endif
  
  static const char * sun3scsi_info (struct Scsi_Host *spnt) {
      return "";
  }
  
  // safe bits for the CSR
  #define CSR_GOOD 0x060f

  static irqreturn_t scsi_sun3_intr(int irq, void *dummy)

  {
  	unsigned short csr = dregs->csr;
  	int handled = 0;
  
  	dregs->csr &= ~CSR_DMA_ENABLE;
  
  
  #ifdef SUN3_SCSI_DEBUG
  	printk("scsi_intr csr %x
  ", csr);
  #endif
  
  	if(csr & ~CSR_GOOD) {
  		if(csr & CSR_DMA_BUSERR) {
  			printk("scsi%d: bus error in dma
  ", default_instance->host_no);
  #ifdef SUN3_SCSI_DEBUG
  			printk("scsi: residual %x count %x addr %p dmaaddr %x
  ", 
  			       dregs->fifo_count,
  			       dregs->dma_count_lo | (dregs->dma_count_hi << 16),
  			       sun3_dma_orig_addr,
  			       dregs->dma_addr_lo | (dregs->dma_addr_hi << 16));
  #endif
  		}
  
  		if(csr & CSR_DMA_CONFLICT) {
  			printk("scsi%d: dma conflict
  ", default_instance->host_no);
  		}
  		handled = 1;
  	}
  
  	if(csr & (CSR_SDB_INT | CSR_DMA_INT)) {

  		NCR5380_intr(irq, dummy);

  		handled = 1;
  	}
  
  	return IRQ_RETVAL(handled);
  }
  
  /*
   * Debug stuff - to be called on NMI, or sysrq key. Use at your own risk; 
   * reentering NCR5380_print_status seems to have ugly side effects
   */
  
  /* this doesn't seem to get used at all -- sam */
  #if 0
  void sun3_sun3_debug (void)
  {
  	unsigned long flags;
  	NCR5380_local_declare();
  
  	if (default_instance) {
  			local_irq_save(flags);
  			NCR5380_print_status(default_instance);
  			local_irq_restore(flags);
  	}
  }
  #endif
  
  
  /* sun3scsi_dma_setup() -- initialize the dma controller for a read/write */
  static unsigned long sun3scsi_dma_setup(void *data, unsigned long count, int write_flag)
  {
  	void *addr;
  
  	if(sun3_dma_orig_addr != NULL)
  		dvma_unmap(sun3_dma_orig_addr);
  
  //	addr = sun3_dvma_page((unsigned long)data, (unsigned long)dmabuf);
  	addr = (void *)dvma_map_vme((unsigned long) data, count);
  		
  	sun3_dma_orig_addr = addr;
  	sun3_dma_orig_count = count;
  	
  #ifdef SUN3_SCSI_DEBUG
  	printk("scsi: dma_setup addr %p count %x
  ", addr, count);
  #endif
  
  //	dregs->fifo_count = 0;
  #if 0	
  	/* reset fifo */
  	dregs->csr &= ~CSR_FIFO;
  	dregs->csr |= CSR_FIFO;
  #endif	
  	/* set direction */
  	if(write_flag)
  		dregs->csr |= CSR_SEND;
  	else
  		dregs->csr &= ~CSR_SEND;
  	
  	/* reset fifo */
  //	dregs->csr &= ~CSR_FIFO;
  //	dregs->csr |= CSR_FIFO;
  
  	dregs->csr |= CSR_PACK_ENABLE;
  
  	dregs->dma_addr_hi = ((unsigned long)addr >> 16);
  	dregs->dma_addr_lo = ((unsigned long)addr & 0xffff);
  	
  	dregs->dma_count_hi = 0;
  	dregs->dma_count_lo = 0;
  	dregs->fifo_count_hi = 0;
  	dregs->fifo_count = 0;
  		
  #ifdef SUN3_SCSI_DEBUG
  	printk("scsi: dma_setup done csr %x
  ", dregs->csr);
  #endif
         	return count;
  
  }
  
  static inline unsigned long sun3scsi_dma_residual(struct Scsi_Host *instance)
  {
  	return last_residual;
  }

  static inline unsigned long sun3scsi_dma_xfer_len(unsigned long wanted,
  						  struct scsi_cmnd *cmd,
  						  int write_flag)

  {

  	if (cmd->request->cmd_type == REQ_TYPE_FS)

   		return wanted;
  	else
  		return 0;
  }
  
  static int sun3scsi_dma_start(unsigned long count, char *data)
  {
  	
  	unsigned short csr;
  
  	csr = dregs->csr;
  #ifdef SUN3_SCSI_DEBUG
  	printk("scsi: dma_start data %p count %x csr %x fifo %x
  ", data, count, csr, dregs->fifo_count);
  #endif
  	
  	dregs->dma_count_hi = (sun3_dma_orig_count >> 16);
  	dregs->dma_count_lo = (sun3_dma_orig_count & 0xffff);
  
  	dregs->fifo_count_hi = (sun3_dma_orig_count >> 16);
  	dregs->fifo_count = (sun3_dma_orig_count & 0xffff);
  
  //	if(!(csr & CSR_DMA_ENABLE))
  //		dregs->csr |= CSR_DMA_ENABLE;
  
  	return 0;
  }
  
  /* clean up after our dma is done */
  static int sun3scsi_dma_finish(int write_flag)
  {
  	unsigned short fifo;
  	int ret = 0;
  	
  	sun3_dma_active = 0;
  
  	dregs->csr &= ~CSR_DMA_ENABLE;
  	
  	fifo = dregs->fifo_count;
  	if(write_flag) {
  		if((fifo > 0) && (fifo < sun3_dma_orig_count))
  			fifo++;
  	}
  
  	last_residual = fifo;
  #ifdef SUN3_SCSI_DEBUG
  	printk("scsi: residual %x total %x
  ", fifo, sun3_dma_orig_count);
  #endif
  	/* empty bytes from the fifo which didn't make it */
  	if((!write_flag) && (dregs->csr & CSR_LEFT)) {
  		unsigned char *vaddr;
  
  #ifdef SUN3_SCSI_DEBUG
  		printk("scsi: got left over bytes
  ");
  #endif
  
  		vaddr = (unsigned char *)dvma_vmetov(sun3_dma_orig_addr);
  		
  		vaddr += (sun3_dma_orig_count - fifo);
  		vaddr--;
  		
  		switch(dregs->csr & CSR_LEFT) {
  		case CSR_LEFT_3:
  			*vaddr = (dregs->bpack_lo & 0xff00) >> 8;
  			vaddr--;
  			
  		case CSR_LEFT_2:
  			*vaddr = (dregs->bpack_hi & 0x00ff);
  			vaddr--;
  			
  		case CSR_LEFT_1:
  			*vaddr = (dregs->bpack_hi & 0xff00) >> 8;
  			break;
  		}
  		
  		
  	}
  
  	dvma_unmap(sun3_dma_orig_addr);
  	sun3_dma_orig_addr = NULL;
  
  	dregs->dma_addr_hi = 0;
  	dregs->dma_addr_lo = 0;
  	dregs->dma_count_hi = 0;
  	dregs->dma_count_lo = 0;
  
  	dregs->fifo_count = 0;
  	dregs->fifo_count_hi = 0;
  
  	dregs->csr &= ~CSR_SEND;
  	
  //	dregs->csr |= CSR_DMA_ENABLE;
  	
  #if 0
  	/* reset fifo */
  	dregs->csr &= ~CSR_FIFO;
  	dregs->csr |= CSR_FIFO;
  #endif	
  	sun3_dma_setup_done = NULL;
  
  	return ret;
  
  }
  
  #include "sun3_NCR5380.c"

  static struct scsi_host_template driver_template = {

  	.name			= SUN3_SCSI_NAME,
  	.detect			= sun3scsi_detect,
  	.release		= sun3scsi_release,
  	.info			= sun3scsi_info,
  	.queuecommand		= sun3scsi_queue_command,
  	.eh_abort_handler      	= sun3scsi_abort,
  	.eh_bus_reset_handler  	= sun3scsi_bus_reset,
  	.can_queue		= CAN_QUEUE,
  	.this_id		= 7,
  	.sg_tablesize		= SG_TABLESIZE,
  	.cmd_per_lun		= CMD_PER_LUN,
  	.use_clustering		= DISABLE_CLUSTERING
  };
  
  
  #include "scsi_module.c"

  MODULE_LICENSE("GPL");