/*
   * Generic Macintosh NCR5380 driver
   *
   * Copyright 1998, Michael Schmitz <mschmitz@lbl.gov>
   *
   * derived in part from:
   */
  /*
   * Generic Generic NCR5380 driver
   *
   * Copyright 1995, Russell King
   *
   * ALPHA RELEASE 1.
   *
   * For more information, please consult
   *
   * NCR 5380 Family
   * SCSI Protocol Controller
   * Databook
   *
   * NCR Microelectronics
   * 1635 Aeroplaza Drive
   * Colorado Springs, CO 80916
   * 1+ (719) 578-3400
   * 1+ (800) 334-5454
   */
  
  /*
   * $Log: mac_NCR5380.c,v $
   */
  
  #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 <linux/interrupt.h>
  
  #include <asm/io.h>
  #include <asm/irq.h>
  #include <asm/system.h>
  
  #include <asm/macintosh.h>
  #include <asm/macints.h>

  #include <asm/mac_via.h>
  
  #include "scsi.h"
  #include <scsi/scsi_host.h>
  #include "mac_scsi.h"

  
  /* These control the behaviour of the generic 5380 core */
  #define AUTOSENSE
  #define PSEUDO_DMA

  #include "NCR5380.h"
  
  #if 0
  #define NDEBUG (NDEBUG_INTR | NDEBUG_PSEUDO_DMA | NDEBUG_ARBITRATION | NDEBUG_SELECTION | NDEBUG_RESELECTION)
  #else
  #define NDEBUG (NDEBUG_ABORT)
  #endif
  
  #define RESET_BOOT
  #define DRIVER_SETUP

  extern void via_scsi_clear(void);
  
  #ifdef RESET_BOOT
  static void mac_scsi_reset_boot(struct Scsi_Host *instance);
  #endif
  
  static int setup_called = 0;
  static int setup_can_queue = -1;
  static int setup_cmd_per_lun = -1;
  static int setup_sg_tablesize = -1;
  static int setup_use_pdma = -1;
  #ifdef SUPPORT_TAGS
  static int setup_use_tagged_queuing = -1;
  #endif
  static int setup_hostid = -1;
  
  /* Time (in jiffies) to wait after a reset; the SCSI standard calls for 250ms,
   * we usually do 0.5s to be on the safe side. But Toshiba CD-ROMs once more
   * need ten times the standard value... */
  #define TOSHIBA_DELAY
  
  #ifdef TOSHIBA_DELAY
  #define	AFTER_RESET_DELAY	(5*HZ/2)
  #else
  #define	AFTER_RESET_DELAY	(HZ/2)
  #endif
  
  static volatile unsigned char *mac_scsi_regp = NULL;
  static volatile unsigned char *mac_scsi_drq  = NULL;
  static volatile unsigned char *mac_scsi_nodrq = NULL;
  
  
  /*
   * NCR 5380 register access functions
   */
  
  #if 0
  /* Debug versions */
  #define CTRL(p,v) (*ctrl = (v))
  
  static char macscsi_read(struct Scsi_Host *instance, int reg)
  {
    int iobase = instance->io_port;
    int i;
    int *ctrl = &((struct NCR5380_hostdata *)instance->hostdata)->ctrl;
  
    CTRL(iobase, 0);
    i = in_8(iobase + (reg<<4));
    CTRL(iobase, 0x40);
  
    return i;
  }
  
  static void macscsi_write(struct Scsi_Host *instance, int reg, int value)
  {
    int iobase = instance->io_port;
    int *ctrl = &((struct NCR5380_hostdata *)instance->hostdata)->ctrl;
  
    CTRL(iobase, 0);
    out_8(iobase + (reg<<4), value);
    CTRL(iobase, 0x40);
  }
  #else
  
  /* Fast versions */
  static __inline__ char macscsi_read(struct Scsi_Host *instance, int reg)
  {
    return in_8(instance->io_port + (reg<<4));
  }
  
  static __inline__ void macscsi_write(struct Scsi_Host *instance, int reg, int value)
  {
    out_8(instance->io_port + (reg<<4), value);
  }
  #endif
  
  
  /*
   * Function : mac_scsi_setup(char *str)
   *
   * Purpose : booter command line initialization of the overrides array,
   *
   * Inputs : str - comma delimited list of options
   *
   */
  
  static int __init mac_scsi_setup(char *str) {
  #ifdef DRIVER_SETUP	
  	int ints[7];
  	
  	(void)get_options( str, ARRAY_SIZE(ints), ints);
  	
  	if (setup_called++ || ints[0] < 1 || ints[0] > 6) {
  	    printk(KERN_WARNING "scsi: <mac5380>"
  		" Usage: mac5380=<can_queue>[,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>,<use_pdma>]
  ");
  	    printk(KERN_ALERT "scsi: <mac5380> Bad Penguin parameters?
  ");
  	    return 0;
  	}
  	    
  	if (ints[0] >= 1) {
  		if (ints[1] > 0)
  			/* no limits on this, just > 0 */
  			setup_can_queue = ints[1];
  	}
  	if (ints[0] >= 2) {
  		if (ints[2] > 0)
  			setup_cmd_per_lun = ints[2];
  	}
  	if (ints[0] >= 3) {
  		if (ints[3] >= 0) {
  			setup_sg_tablesize = ints[3];
  			/* Must be <= SG_ALL (255) */
  			if (setup_sg_tablesize > SG_ALL)
  				setup_sg_tablesize = SG_ALL;
  		}
  	}
  	if (ints[0] >= 4) {
  		/* Must be between 0 and 7 */
  		if (ints[4] >= 0 && ints[4] <= 7)
  			setup_hostid = ints[4];
  		else if (ints[4] > 7)
  			printk(KERN_WARNING "mac_scsi_setup: invalid host ID %d !
  ", ints[4] );
  	}
  #ifdef SUPPORT_TAGS	
  	if (ints[0] >= 5) {
  		if (ints[5] >= 0)
  			setup_use_tagged_queuing = !!ints[5];
  	}
  	
  	if (ints[0] == 6) {
  	    if (ints[6] >= 0)
  		setup_use_pdma = ints[6];
  	}
  #else
  	if (ints[0] == 5) {
  	    if (ints[5] >= 0)
  		setup_use_pdma = ints[5];
  	}
  #endif /* SUPPORT_TAGS */
  	
  #endif /* DRIVER_SETUP */
  	return 1;
  }
  
  __setup("mac5380=", mac_scsi_setup);
  
  /*

   * Function : int macscsi_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.
   *
   */
   

  int __init macscsi_detect(struct scsi_host_template * tpnt)

  {
      static int called = 0;
      int flags = 0;
      struct Scsi_Host *instance;
  
      if (!MACH_IS_MAC || called)
  	return( 0 );
  
      if (macintosh_config->scsi_type != MAC_SCSI_OLD)
  	return( 0 );
  
      /* 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;
      }
  
  #ifdef SUPPORT_TAGS
      if (setup_use_tagged_queuing < 0)
  	setup_use_tagged_queuing = USE_TAGGED_QUEUING;
  #endif
  
      /* Once we support multiple 5380s (e.g. DuoDock) we'll do
         something different here */
      instance = scsi_register (tpnt, sizeof(struct NCR5380_hostdata));

      if (macintosh_config->ident == MAC_MODEL_IIFX) {
  	mac_scsi_regp  = via1+0x8000;
  	mac_scsi_drq   = via1+0xE000;
  	mac_scsi_nodrq = via1+0xC000;
  	/* The IIFX should be able to do true DMA, but pseudo-dma doesn't work */
  	flags = FLAG_NO_PSEUDO_DMA;
      } else {
  	mac_scsi_regp  = via1+0x10000;
  	mac_scsi_drq   = via1+0x6000;
  	mac_scsi_nodrq = via1+0x12000;
      }
  
      if (! setup_use_pdma)
  	flags = FLAG_NO_PSEUDO_DMA;
  	
      instance->io_port = (unsigned long) mac_scsi_regp;
      instance->irq = IRQ_MAC_SCSI;
  
  #ifdef RESET_BOOT   
      mac_scsi_reset_boot(instance);
  #endif
      
      NCR5380_init(instance, flags);
  
      instance->n_io_port = 255;
  
      ((struct NCR5380_hostdata *)instance->hostdata)->ctrl = 0;
  
      if (instance->irq != SCSI_IRQ_NONE)

  	if (request_irq(instance->irq, NCR5380_intr, 0, "ncr5380", instance)) {

  	    printk(KERN_WARNING "scsi%d: IRQ%d not free, interrupts disabled
  ",
  		   instance->host_no, instance->irq);
  	    instance->irq = SCSI_IRQ_NONE;
  	}
  
      printk(KERN_INFO "scsi%d: generic 5380 at port %lX irq", instance->host_no, instance->io_port);
      if (instance->irq == SCSI_IRQ_NONE)
  	printk (KERN_INFO "s disabled");
      else
  	printk (KERN_INFO " %d", instance->irq);
      printk(KERN_INFO " options CAN_QUEUE=%d CMD_PER_LUN=%d release=%d",
  	   instance->can_queue, instance->cmd_per_lun, MACSCSI_PUBLIC_RELEASE);
      printk(KERN_INFO "
  scsi%d:", instance->host_no);
      NCR5380_print_options(instance);
      printk("
  ");
      called = 1;
      return 1;
  }
  
  int macscsi_release (struct Scsi_Host *shpnt)
  {
  	if (shpnt->irq != SCSI_IRQ_NONE)

  		free_irq(shpnt->irq, shpnt);

  	NCR5380_exit(shpnt);
  
  	return 0;
  }
  
  #ifdef RESET_BOOT
  /*
   * Our 'bus reset on boot' function
   */
  
  static void mac_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(KERN_INFO "Macintosh SCSI: resetting the SCSI bus..." );
  
  	/* switch off SCSI IRQ - catch an interrupt without IRQ bit set else */

  	disable_irq(IRQ_MAC_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 */

  	enable_irq(IRQ_MAC_SCSI);

  
  	printk(KERN_INFO " done
  " );
  }
  #endif
  
  const char * macscsi_info (struct Scsi_Host *spnt) {
  	return "";
  }
  
  /* 
     Pseudo-DMA: (Ove Edlund)
     The code attempts to catch bus errors that occur if one for example
     "trips over the cable".
     XXX: Since bus errors in the PDMA routines never happen on my 
     computer, the bus error code is untested. 
     If the code works as intended, a bus error results in Pseudo-DMA 
     beeing disabled, meaning that the driver switches to slow handshake. 
     If bus errors are NOT extremely rare, this has to be changed. 
  */
  
  #define CP_IO_TO_MEM(s,d,len)				\
  __asm__ __volatile__					\
      ("    cmp.w  #4,%2
  "				\
       "    bls    8f
  "					\
       "    move.w %1,%%d0
  "				\
       "    neg.b  %%d0
  "				\
       "    and.w  #3,%%d0
  "				\
       "    sub.w  %%d0,%2
  "				\
       "    bra    2f
  "					\
       " 1: move.b (%0),(%1)+
  "				\
       " 2: dbf    %%d0,1b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #5,%%d0
  "				\
       "    bra    4f
  "					\
       " 3: move.l (%0),(%1)+
  "				\
       "31: move.l (%0),(%1)+
  "				\
       "32: move.l (%0),(%1)+
  "				\
       "33: move.l (%0),(%1)+
  "				\
       "34: move.l (%0),(%1)+
  "				\
       "35: move.l (%0),(%1)+
  "				\
       "36: move.l (%0),(%1)+
  "				\
       "37: move.l (%0),(%1)+
  "				\
       " 4: dbf    %%d0,3b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #2,%%d0
  "				\
       "    and.w  #7,%%d0
  "				\
       "    bra    6f
  "					\
       " 5: move.l (%0),(%1)+
  "				\
       " 6: dbf    %%d0,5b
  "				\
       "    and.w  #3,%2
  "				\
       "    bra    8f
  "					\
       " 7: move.b (%0),(%1)+
  "				\
       " 8: dbf    %2,7b
  "				\
       "    moveq.l #0, %2
  "				\
       " 9: 
  "						\
       ".section .fixup,\"ax\"
  "				\
       "    .even
  "					\
       "90: moveq.l #1, %2
  "				\
       "    jra 9b
  "					\
       ".previous
  "					\
       ".section __ex_table,\"a\"
  "			\
       "   .align 4
  "					\
       "   .long  1b,90b
  "				\
       "   .long  3b,90b
  "				\
       "   .long 31b,90b
  "				\
       "   .long 32b,90b
  "				\
       "   .long 33b,90b
  "				\
       "   .long 34b,90b
  "				\
       "   .long 35b,90b
  "				\
       "   .long 36b,90b
  "				\
       "   .long 37b,90b
  "				\
       "   .long  5b,90b
  "				\
       "   .long  7b,90b
  "				\
       ".previous"					\
       : "=a"(s), "=a"(d), "=d"(len)			\
       : "0"(s), "1"(d), "2"(len)				\
       : "d0")
  
  
  static int macscsi_pread (struct Scsi_Host *instance,
  			  unsigned char *dst, int len)
  {
     unsigned char *d;
     volatile unsigned char *s;
  
     NCR5380_local_declare();
     NCR5380_setup(instance);
  
     s = mac_scsi_drq+0x60;
     d = dst;
  
  /* These conditions are derived from MacOS */
  
     while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) 
           && !(NCR5380_read(STATUS_REG) & SR_REQ))
        ;
     if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) 
           && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH)) {
        printk(KERN_ERR "Error in macscsi_pread
  ");
        return -1;
     }
  
     CP_IO_TO_MEM(s, d, len);
     
     if (len != 0) {
        printk(KERN_NOTICE "Bus error in macscsi_pread
  ");
        return -1;
     }
     
     return 0;
  }
  
  
  #define CP_MEM_TO_IO(s,d,len)				\
  __asm__ __volatile__					\
      ("    cmp.w  #4,%2
  "				\
       "    bls    8f
  "					\
       "    move.w %0,%%d0
  "				\
       "    neg.b  %%d0
  "				\
       "    and.w  #3,%%d0
  "				\
       "    sub.w  %%d0,%2
  "				\
       "    bra    2f
  "					\
       " 1: move.b (%0)+,(%1)
  "				\
       " 2: dbf    %%d0,1b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #5,%%d0
  "				\
       "    bra    4f
  "					\
       " 3: move.l (%0)+,(%1)
  "				\
       "31: move.l (%0)+,(%1)
  "				\
       "32: move.l (%0)+,(%1)
  "				\
       "33: move.l (%0)+,(%1)
  "				\
       "34: move.l (%0)+,(%1)
  "				\
       "35: move.l (%0)+,(%1)
  "				\
       "36: move.l (%0)+,(%1)
  "				\
       "37: move.l (%0)+,(%1)
  "				\
       " 4: dbf    %%d0,3b
  "				\
       "    move.w %2,%%d0
  "				\
       "    lsr.w  #2,%%d0
  "				\
       "    and.w  #7,%%d0
  "				\
       "    bra    6f
  "					\
       " 5: move.l (%0)+,(%1)
  "				\
       " 6: dbf    %%d0,5b
  "				\
       "    and.w  #3,%2
  "				\
       "    bra    8f
  "					\
       " 7: move.b (%0)+,(%1)
  "				\
       " 8: dbf    %2,7b
  "				\
       "    moveq.l #0, %2
  "				\
       " 9: 
  "						\
       ".section .fixup,\"ax\"
  "				\
       "    .even
  "					\
       "90: moveq.l #1, %2
  "				\
       "    jra 9b
  "					\
       ".previous
  "					\
       ".section __ex_table,\"a\"
  "			\
       "   .align 4
  "					\
       "   .long  1b,90b
  "				\
       "   .long  3b,90b
  "				\
       "   .long 31b,90b
  "				\
       "   .long 32b,90b
  "				\
       "   .long 33b,90b
  "				\
       "   .long 34b,90b
  "				\
       "   .long 35b,90b
  "				\
       "   .long 36b,90b
  "				\
       "   .long 37b,90b
  "				\
       "   .long  5b,90b
  "				\
       "   .long  7b,90b
  "				\
       ".previous"					\
       : "=a"(s), "=a"(d), "=d"(len)			\
       : "0"(s), "1"(d), "2"(len)				\
       : "d0")
  
  static int macscsi_pwrite (struct Scsi_Host *instance,
  				  unsigned char *src, int len)
  {
     unsigned char *s;
     volatile unsigned char *d;
  
     NCR5380_local_declare();
     NCR5380_setup(instance);
  
     s = src;
     d = mac_scsi_drq;
     
  /* These conditions are derived from MacOS */
  
     while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) 
           && (!(NCR5380_read(STATUS_REG) & SR_REQ) 
              || (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH))) 
        ;
     if (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ)) {
        printk(KERN_ERR "Error in macscsi_pwrite
  ");
        return -1;
     }
  
     CP_MEM_TO_IO(s, d, len);   
  
     if (len != 0) {
        printk(KERN_NOTICE "Bus error in macscsi_pwrite
  ");
        return -1;
     }
     
     return 0;
  }

  #include "NCR5380.c"

  static struct scsi_host_template driver_template = {

  	.proc_name			= "Mac5380",
  	.proc_info			= macscsi_proc_info,
  	.name				= "Macintosh NCR5380 SCSI",
  	.detect				= macscsi_detect,
  	.release			= macscsi_release,
  	.info				= macscsi_info,
  	.queuecommand			= macscsi_queue_command,
  	.eh_abort_handler		= macscsi_abort,
  	.eh_bus_reset_handler		= macscsi_bus_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"