/* $Id: wd7000.c,v 1.2 1994/01/15 06:02:32 drew Exp $ *  linux/kernel/wd7000.c * *  Copyright (C) 1992  Thomas Wuensche *	closely related to the aha1542 driver from Tommy Thorn *	( as close as different hardware allows on a lowlevel-driver :-) ) * *  Revised (and renamed) by John Boyd <boyd@cis.ohio-state.edu> to *  accomodate Eric Youngdale's modifications to scsi.c.  Nov 1992. * *  Additional changes to support scatter/gather.  Dec. 1992.  tw/jb */#include <stdarg.h>#include <linux/kernel.h>#include <linux/head.h>#include <linux/types.h>#include <linux/string.h>#include <linux/sched.h>#include <asm/system.h>#include <asm/dma.h>#include <asm/io.h>#include <linux/ioport.h>#include "../block/blk.h"#include "scsi.h"#include "hosts.h"/* #define DEBUG  */#include "wd7000.h"#ifdef DEBUG#define DEB(x) x#else#define DEB(x)#endif/*   Driver data structures:   - mb and scbs are required for interfacing with the host adapter.     An SCB has extra fields not visible to the adapter; mb's     _cannot_ do this, since the adapter assumes they are contiguous in     memory, 4 bytes each, with ICMBs following OGMBs, and uses this fact     to access them.   - An icb is for host-only (non-SCSI) commands.  ICBs are 16 bytes each;     the additional bytes are used only by the driver.   - For now, a pool of SCBs are kept in global storage by this driver,     and are allocated and freed as needed.  The 7000-FASST2 marks OGMBs empty as soon as it has _started_ a command,  not when it has finished.  Since the SCB must be around for completion,  problems arise when SCBs correspond to OGMBs, which may be reallocated  earlier (or delayed unnecessarily until a command completes).  Mailboxes are used as transient data structures, simply for  carrying SCB addresses to/from the 7000-FASST2.  Note also since SCBs are not "permanently" associated with mailboxes,  there is no need to keep a global list of Scsi_Cmnd pointers indexed  by OGMB.   Again, SCBs reference their Scsi_Cmnds directly, so mailbox  indices need not be involved.*/static struct {       struct wd_mailbox ogmb[OGMB_CNT];        struct wd_mailbox icmb[ICMB_CNT];} mb;static int next_ogmb = 0;   /* to reduce contention at mailboxes */static Scb scbs[MAX_SCBS];static Scb *scbfree = NULL;static int wd7000_host = 0;static unchar controlstat = 0;static unchar rev_1 = 0, rev_2 = 0;  /* filled in by wd7000_revision */#define wd7000_intr_ack()  outb(0,INTR_ACK)#define WAITnexttimeout 3000000static inline void wd7000_enable_intr(void){    controlstat |= INT_EN;    outb(controlstat,CONTROL);}static inline void wd7000_enable_dma(void){    controlstat |= DMA_EN;    outb(controlstat,CONTROL);    set_dma_mode(DMA_CH, DMA_MODE_CASCADE);    enable_dma(DMA_CH);}#define WAIT(port, mask, allof, noneof)					\ { register WAITbits;							\   register WAITtimeout = WAITnexttimeout;				\   while (1) {								\     WAITbits = inb(port) & (mask);					\     if ((WAITbits & (allof)) == (allof) && ((WAITbits & (noneof)) == 0)) \       break;                                                         	\     if (--WAITtimeout == 0) goto fail;					\   }									\ }static inline void delay( unsigned how_long ){     unsigned long time = jiffies + how_long;     while (jiffies < time);}static inline int command_out(unchar *cmdp, int len){    while (len--)  {        WAIT(ASC_STAT, STATMASK, CMD_RDY, 0);	outb(*cmdp++, COMMAND);    }    return 1;fail:    printk("wd7000_out WAIT failed(%d): ", len+1);    return 0;}static inline Scb *alloc_scb(void){    Scb *scb;    unsigned long flags;    save_flags(flags);    cli();    if (scbfree == NULL)  {        panic("wd7000: can't allocate free SCB.\n");	restore_flags(flags);	return NULL;    }    scb = scbfree;  scbfree = scb->next;    memset(scb, 0, sizeof(Scb));  scb->next = NULL;    restore_flags(flags);    return scb;}static inline void free_scb( Scb *scb ){    unsigned long flags;    save_flags(flags);    cli();    memset(scb, 0, sizeof(Scb));    scb->next = scbfree;  scbfree = scb;    restore_flags(flags);}static inline void init_scbs(void){    int i;    unsigned long flags;    save_flags(flags);    cli();    scbfree = &(scbs[0]);    for (i = 0;  i < MAX_SCBS-1;  i++)  scbs[i].next = &(scbs[i+1]);    scbs[MAX_SCBS-1].next = NULL;    restore_flags(flags);}        static int mail_out( Scb *scbptr )/* *  Note: this can also be used for ICBs; just cast to the parm type. */{    int i, ogmb;    unsigned long flags;    DEB(printk("wd7000_scb_out: %06x");)    /* We first look for a free outgoing mailbox */    save_flags(flags);    cli();    ogmb = next_ogmb;    for (i = 0; i < OGMB_CNT; i++) {	if (mb.ogmb[ogmb].status == 0)  {	    DEB(printk(" using OGMB %x",ogmb));	    mb.ogmb[ogmb].status = 1;	    any2scsi(mb.ogmb[ogmb].scbptr, scbptr);	    next_ogmb = (ogmb+1) % OGMB_CNT;	    break;	}  else	    ogmb = (++ogmb) % OGMB_CNT;    }    restore_flags(flags);    DEB(printk(", scb is %x",scbptr);)    if (i >= OGMB_CNT) {        DEB(printk(", no free OGMBs.\n");)	/* Alternatively, issue "interrupt on free OGMB", and sleep... */        return 0;    }    wd7000_enable_intr();     do  {        WAIT(ASC_STAT,STATMASK,CMD_RDY,0);	outb(START_OGMB|ogmb, COMMAND);	WAIT(ASC_STAT,STATMASK,CMD_RDY,0);    }  while (inb(ASC_STAT) & CMD_REJ);    DEB(printk(", awaiting interrupt.\n");)    return 1;fail:    DEB(printk(", WAIT timed out.\n");)    return 0;}int make_code(unsigned hosterr, unsigned scsierr){   #ifdef DEBUG    int in_error = hosterr;#endif    switch ((hosterr>>8)&0xff){	case 0:	/* Reserved */		hosterr = DID_ERROR;		break;	case 1:	/* Command Complete, no errors */		hosterr = DID_OK;		break;	case 2: /* Command complete, error logged in scb status (scsierr) */ 		hosterr = DID_OK;		break;	case 4:	/* Command failed to complete - timeout */		hosterr = DID_TIME_OUT;		break;	case 5:	/* Command terminated; Bus reset by external device */		hosterr = DID_RESET;		break;	case 6:	/* Unexpected Command Received w/ host as target */		hosterr = DID_BAD_TARGET;		break;	case 80: /* Unexpected Reselection */        case 81: /* Unexpected Selection */		hosterr = DID_BAD_INTR;		break;        case 82: /* Abort Command Message  */		hosterr = DID_ABORT;		break;	case 83: /* SCSI Bus Software Reset */	case 84: /* SCSI Bus Hardware Reset */		hosterr = DID_RESET;		break;        default: /* Reserved */		hosterr = DID_ERROR;		break;	}#ifdef DEBUG    if (scsierr||hosterr)        printk("\nSCSI command error: SCSI %02x host %04x return %d",	       scsierr,in_error,hosterr);#endif    return scsierr | (hosterr << 16);}static void wd7000_scsi_done(Scsi_Cmnd * SCpnt){    DEB(printk("wd7000_scsi_done: %06x\n",SCpnt);)    SCpnt->SCp.phase = 0;}void wd7000_intr_handle(int irq){    int flag, icmb, errstatus, icmb_status;    int host_error, scsi_error;    Scb *scb;             /* for SCSI commands */    unchar *icb;          /* for host commands */    Scsi_Cmnd *SCpnt;    flag = inb(INTR_STAT);    DEB(printk("wd7000_intr_handle: intr stat = %02x",flag);)    if (!(inb(ASC_STAT)&0x80)){ 	DEB(printk("\nwd7000_intr_handle: phantom interrupt...\n");)	wd7000_intr_ack();	return;     }    /* check for an incoming mailbox */    if ((flag & 0x40) == 0) {        /*  for a free OGMB - need code for this case... */        DEB(printk("wd7000_intr_handle: free outgoing mailbox\n");)