ncr53c9x.c

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		break;
	case fas216:
	case fas236:
	case fsc:
		/* Fast ESP variants */
		esp_write(eregs->esp_cfg2, esp->config2);
		for(i=0; i<8; i++)
			esp->config3[i] |= ESP_CONFIG3_FCLK;
		esp->prev_cfg3 = esp->config3[0];
		esp_write(eregs->esp_cfg3, esp->prev_cfg3);
		if(esp->diff)
			esp->radelay = 0;
		else
			esp->radelay = 16;
		/* Different timeout constant for these chips */
		esp->neg_defp =
			FSC_NEG_DEFP(esp->cfreq,
				     (esp->cfact == ESP_CCF_F0 ?
				      ESP_CCF_F7 + 1 : esp->cfact));
		esp_write(eregs->esp_timeo, esp->neg_defp);
		/* Enable Active Negotiation if possible */
		if((esp->erev == fsc) && !esp->diff)
			esp_write(eregs->esp_cfg4, ESP_CONFIG4_EAN);
		break;
	case fas100a:
		/* Fast 100a */
		esp_write(eregs->esp_cfg2, esp->config2);
		for(i=0; i<8; i++)
			esp->config3[i] |= ESP_CONFIG3_FCLOCK;
		esp->prev_cfg3 = esp->config3[0];
		esp_write(eregs->esp_cfg3, esp->prev_cfg3);
		esp->radelay = 32;
		break;
	default:
		panic("esp: what could it be... I wonder...");
		break;
	};

	/* Eat any bitrot in the chip */
	trash = esp_read(eregs->esp_intrpt);
	udelay(100);
}

/* This places the ESP into a known state at boot time. */
void esp_bootup_reset(struct NCR_ESP *esp, struct ESP_regs *eregs)
{
	volatile unchar trash;

	/* Reset the DMA */
	if(esp->dma_reset)
		esp->dma_reset(esp);

	/* Reset the ESP */
	esp_reset_esp(esp, eregs);

	/* Reset the SCSI bus, but tell ESP not to generate an irq */
	esp_write(eregs->esp_cfg1, (esp_read(eregs->esp_cfg1) | ESP_CONFIG1_SRRDISAB));
	esp_cmd(esp, eregs, ESP_CMD_RS);
	udelay(400);
	esp_write(eregs->esp_cfg1, esp->config1);

	/* Eat any bitrot in the chip and we are done... */
	trash = esp_read(eregs->esp_intrpt);
}

/* Allocate structure and insert basic data such as SCSI chip frequency
 * data and a pointer to the device
 */
struct NCR_ESP* esp_allocate(Scsi_Host_Template *tpnt, void *esp_dev)
{
	struct NCR_ESP *esp, *elink;
	struct Scsi_Host *esp_host;

	esp_host = scsi_register(tpnt, sizeof(struct NCR_ESP));
	if(!esp_host)
		panic("Cannot register ESP SCSI host");
	esp = (struct NCR_ESP *) esp_host->hostdata;
	if(!esp)
		panic("No esp in hostdata");
	esp->ehost = esp_host;
	esp->edev = esp_dev;
	esp->esp_id = nesps++;

	/* Set bitshift value (only used on Amiga with multiple ESPs) */
	esp->shift = 2;

	/* Put into the chain of esp chips detected */
	if(espchain) {
		elink = espchain;
		while(elink->next) elink = elink->next;
		elink->next = esp;
	} else {
		espchain = esp;
	}
	esp->next = 0;

	return esp;
}

void esp_deallocate(struct NCR_ESP *esp)
{
	struct NCR_ESP *elink;

	if(espchain == esp) {
		espchain = 0;
	} else {
		for(elink = espchain; elink && (elink->next != esp); elink = elink->next);
		if(elink) 
			elink->next = esp->next;
	}
	nesps--;
}

/* Complete initialization of ESP structure and device
 * Caller must have initialized appropriate parts of the ESP structure
 * between the call to esp_allocate and this function.
 */
void esp_initialize(struct NCR_ESP *esp)
{
	struct ESP_regs *eregs = esp->eregs;
	unsigned int fmhz;
	unchar ccf;
	int i;
	
	/* Check out the clock properties of the chip. */

	/* This is getting messy but it has to be done
	 * correctly or else you get weird behavior all
	 * over the place.  We are trying to basically
	 * figure out three pieces of information.
	 *
	 * a) Clock Conversion Factor
	 *
	 *    This is a representation of the input
	 *    crystal clock frequency going into the
	 *    ESP on this machine.  Any operation whose
	 *    timing is longer than 400ns depends on this
	 *    value being correct.  For example, you'll
	 *    get blips for arbitration/selection during
	 *    high load or with multiple targets if this
	 *    is not set correctly.
	 *
	 * b) Selection Time-Out
	 *
	 *    The ESP isn't very bright and will arbitrate
	 *    for the bus and try to select a target
	 *    forever if you let it.  This value tells
	 *    the ESP when it has taken too long to
	 *    negotiate and that it should interrupt
	 *    the CPU so we can see what happened.
	 *    The value is computed as follows (from
	 *    NCR/Symbios chip docs).
	 *
	 *          (Time Out Period) *  (Input Clock)
	 *    STO = ----------------------------------
	 *          (8192) * (Clock Conversion Factor)
	 *
	 *    You usually want the time out period to be
	 *    around 250ms, I think we'll set it a little
	 *    bit higher to account for fully loaded SCSI
	 *    bus's and slow devices that don't respond so
	 *    quickly to selection attempts. (yeah, I know
	 *    this is out of spec. but there is a lot of
	 *    buggy pieces of firmware out there so bite me)
	 *
	 * c) Imperical constants for synchronous offset
	 *    and transfer period register values
	 *
	 *    This entails the smallest and largest sync
	 *    period we could ever handle on this ESP.
	 */
	
	fmhz = esp->cfreq;

	if(fmhz <= (5000000))
		ccf = 0;
	else
		ccf = (((5000000 - 1) + (fmhz))/(5000000));
	if(!ccf || ccf > 8) {
		/* If we can't find anything reasonable,
		 * just assume 20MHZ.  This is the clock
		 * frequency of the older sun4c's where I've
		 * been unable to find the clock-frequency
		 * PROM property.  All other machines provide
		 * useful values it seems.
		 */
		ccf = ESP_CCF_F4;
		fmhz = (20000000);
	}
	if(ccf==(ESP_CCF_F7+1))
		esp->cfact = ESP_CCF_F0;
	else if(ccf == ESP_CCF_NEVER)
		esp->cfact = ESP_CCF_F2;
	else
		esp->cfact = ccf;
	esp->cfreq = fmhz;
	esp->ccycle = ESP_MHZ_TO_CYCLE(fmhz);
	esp->ctick = ESP_TICK(ccf, esp->ccycle);
	esp->neg_defp = ESP_NEG_DEFP(fmhz, ccf);
	esp->sync_defp = SYNC_DEFP_SLOW;

	printk("SCSI ID %d Clk %dMHz CCF=%d TOut %d ",
	       esp->scsi_id, (esp->cfreq / 1000000),
	       ccf, (int) esp->neg_defp);

	/* Fill in ehost data */
	esp->ehost->base = (unsigned long)eregs;
	esp->ehost->this_id = esp->scsi_id;
	esp->ehost->irq = esp->irq;

	/* SCSI id mask */
	esp->scsi_id_mask = (1 << esp->scsi_id);

	/* Probe the revision of this esp */
	esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
	esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
	esp_write(eregs->esp_cfg2, esp->config2);
	if((esp_read(eregs->esp_cfg2) & ~(ESP_CONFIG2_MAGIC)) !=
	   (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
		printk("NCR53C90(esp100)\n");
		esp->erev = esp100;
	} else {
		esp->config2 = 0;
		esp_write(eregs->esp_cfg2, 0);
		esp_write(eregs->esp_cfg3, 5);
		if(esp_read(eregs->esp_cfg3) != 5) {
			printk("NCR53C90A(esp100a)\n");
			esp->erev = esp100a;
		} else {
			int target;

			for(target=0; target<8; target++)
				esp->config3[target] = 0;
			esp->prev_cfg3 = 0;
			esp_write(eregs->esp_cfg3, 0);
			if(ccf > ESP_CCF_F5) {
				printk("NCR53C9XF(espfast)\n");
				esp->erev = fast;
				esp->sync_defp = SYNC_DEFP_FAST;
			} else {
				printk("NCR53C9x(esp236)\n");
				esp->erev = esp236;
			}
		}
	}				

	/* Initialize the command queues */
	esp->current_SC = 0;
	esp->disconnected_SC = 0;
	esp->issue_SC = 0;

	/* Clear the state machines. */
	esp->targets_present = 0;
	esp->resetting_bus = 0;
	esp->snip = 0;
	esp->fas_premature_intr_workaround = 0;
	for(i = 0; i < 32; i++)
		esp->espcmdlog[i] = 0;
	esp->espcmdent = 0;
	for(i = 0; i < 16; i++) {
		esp->cur_msgout[i] = 0;
		esp->cur_msgin[i] = 0;
	}
	esp->prevmsgout = esp->prevmsgin = 0;
	esp->msgout_len = esp->msgin_len = 0;

	/* Clear the one behind caches to hold unmatchable values. */
	esp->prev_soff = esp->prev_stp = esp->prev_cfg3 = 0xff;

	/* Reset the thing before we try anything... */
	esp_bootup_reset(esp, eregs);

#ifdef MODULE
	MOD_INC_USE_COUNT;
#endif
	esps_in_use++;
}

/* The info function will return whatever useful
 * information the developer sees fit.  If not provided, then
 * the name field will be used instead.
 */
const char *esp_info(struct Scsi_Host *host)
{
	struct NCR_ESP *esp;

	esp = (struct NCR_ESP *) host->hostdata;
	switch(esp->erev) {
	case esp100:
		return "ESP100 (NCR53C90)";
	case esp100a:
		return "ESP100A (NCR53C90A)";
	case esp236:
		return "ESP236 (NCR53C9x)";
	case fas216:
		return "Emulex FAS216";
	case fas236:
		return "Emulex FAS236";
	case fas366:
		return "QLogic FAS366";
	case fas100a:
		return "FPESP100A";
	case fsc:
		return "Symbios Logic 53CF9x-2";
	default:
		panic("Bogon ESP revision");
	};
}

/* From Wolfgang Stanglmeier's NCR scsi driver. */
struct info_str
{
	char *buffer;
	int length;
	int offset;
	int pos;
};

static void copy_mem_info(struct info_str *info, char *data, int len)
{
	if (info->pos + len > info->length)
		len = info->length - info->pos;

	if (info->pos + len < info->offset) {
		info->pos += len;
		return;
	}
	if (info->pos < info->offset) {
		data += (info->offset - info->pos);
		len  -= (info->offset - info->pos);
	}

	if (len > 0) {
		memcpy(info->buffer + info->pos, data, len);
		info->pos += len;
	}
}

static int copy_info(struct info_str *info, char *fmt, ...)
{
	va_list args;
	char buf[81];
	int len;

	va_start(args, fmt);
	len = vsprintf(buf, fmt, args);
	va_end(args);

	copy_mem_info(info, buf, len);
	return len;
}

static int esp_host_info(struct NCR_ESP *esp, char *ptr, off_t offset, int len)
{
	struct info_str info;
	int i;

	info.buffer	= ptr;
	info.length	= len;
	info.offset	= offset;
	info.pos	= 0;

	copy_info(&info, "ESP Host Adapter:\n");
	copy_info(&info, "\tESP Model\t\t");
	switch(esp->erev) {
	case esp100:
		copy_info(&info, "ESP100 (NCR53C90)\n");
		break;
	case esp100a:
		copy_info(&info, "ESP100A (NCR53C90A)\n");
		break;
	case esp236:
		copy_info(&info, "ESP236 (NCR53C9x)\n");
		break;
	case fas216:
		copy_info(&info, "Emulex FAS216\n");
		break;
	case fas236:
		copy_info(&info, "Emulex FAS236\n");
		break;
	case fas100a:
		copy_info(&info, "FPESP100A\n");
		break;
	case fast:
		copy_info(&info, "Generic FAST\n");
		break;
	case fas366:
		copy_info(&info, "QLogic FAS366\n");
		break;
	case fsc:
		copy_info(&info, "Symbios Logic 53C9x-2\n");
		break;
	case espunknown:
	default:
		copy_info(&info, "Unknown!\n");
		break;
	};
	copy_info(&info, "\tLive Targets\t\t[ ");
	for(i = 0; i < 15; i++) {
		if(esp->targets_present & (1 << i))
			copy_info(&info, "%d ", i);
	}
	copy_info(&info, "]\n\n");
	
	/* Now describe the state of each existing target. */
	copy_info(&info, "Target #\tconfig3\t\tSync Capabilities\tDisconnect\n");
	for(i = 0; i < 15; i++) {
		if(esp->targets_present & (1 << i)) {
			Scsi_Device *SDptr = esp->ehost->host_queue;

			while((SDptr->host != esp->ehost) &&
			      (SDptr->id != i) &&
			      (SDptr->next))
				SDptr = SDptr->next;

			copy_info(&info, "%d\t\t", i);
			copy_info(&info, "%08lx\t", esp->config3[i]);
			copy_info(&info, "[%02lx,%02lx]\t\t\t", SDptr->sync_max_offset,
				  SDptr->sync_min_period);
			copy_info(&info, "%s\n", SDptr->disconnect ? "yes" : "no");
		}
	}

	return info.pos > info.offset? info.pos - info.offset : 0;
}

/* ESP proc filesystem code. */
int esp_proc_info(char *buffer, char **start, off_t offset, int length,
		  int hostno, int inout)
{
	struct NCR_ESP *esp;

	if(inout)
		return -EINVAL; /* not yet */

	for_each_esp(esp) {
		if(esp->ehost->host_no == hostno)
			break;
	}
	if(!esp)
		return -EINVAL;

	if(start)
		*start = buffer;

	return esp_host_info(esp, buffer, offset, length);
}

static void esp_get_dmabufs(struct NCR_ESP *esp, Scsi_Cmnd *sp)
{
	if(sp->use_sg == 0) {
		sp->SCp.this_residual = sp->request_bufflen;
		sp->SCp.buffer = (struct scatterlist *) sp->request_buffer;
		sp->SCp.buffers_residual = 0;
		if (esp->dma_mmu_get_scsi_one)
			esp->dma_mmu_get_scsi_one(esp, sp);
		else
			sp->SCp.have_data_in = (int) sp->SCp.ptr =
				(char *) virt_to_phys(sp->request_buffer);
	} else {
		sp->SCp.buffer = (struct scatterlist *) sp->buffer;
		sp->SCp.buffers_residual = sp->use_sg - 1;
		sp->SCp.this_residual = sp->SCp.buffer->length;
		if (esp->dma_mmu_get_scsi_sgl)