Release 4.11 drivers/scsi/aha1542.c

/*
 *  Driver for Adaptec AHA-1542 SCSI host adapters
 *
 *  Copyright (C) 1992  Tommy Thorn
 *  Copyright (C) 1993, 1994, 1995 Eric Youngdale
 *  Copyright (C) 2015 Ondrej Zary
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/isa.h>
#include <linux/pnp.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <asm/dma.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include "aha1542.h"


#define MAXBOARDS 4


static bool isapnp = 1;
module_param(isapnp, bool, 0);
MODULE_PARM_DESC(isapnp, "enable PnP support (default=1)");


static int io[MAXBOARDS] = { 0x330, 0x334, 0, 0 };
module_param_array(io, int, NULL, 0);
MODULE_PARM_DESC(io, "base IO address of controller (0x130,0x134,0x230,0x234,0x330,0x334, default=0x330,0x334)");

/* time AHA spends on the AT-bus during data transfer */

static int bus_on[MAXBOARDS] = { -1, -1, -1, -1 }; 
/* power-on default: 11us */
module_param_array(bus_on, int, NULL, 0);
MODULE_PARM_DESC(bus_on, "bus on time [us] (2-15, default=-1 [HW default: 11])");

/* time AHA spends off the bus (not to monopolize it) during data transfer  */

static int bus_off[MAXBOARDS] = { -1, -1, -1, -1 }; 
/* power-on default: 4us */
module_param_array(bus_off, int, NULL, 0);
MODULE_PARM_DESC(bus_off, "bus off time [us] (1-64, default=-1 [HW default: 4])");

/* default is jumper selected (J1 on 1542A), factory default = 5 MB/s */

static int dma_speed[MAXBOARDS] = { -1, -1, -1, -1 };
module_param_array(dma_speed, int, NULL, 0);
MODULE_PARM_DESC(dma_speed, "DMA speed [MB/s] (5,6,7,8,10, default=-1 [by jumper])");


#define BIOS_TRANSLATION_6432 1	
/* Default case these days */

#define BIOS_TRANSLATION_25563 2	
/* Big disk case */


struct aha1542_hostdata {
	/* This will effectively start both of them at the first mailbox */
	
int bios_translation;	/* Mapping bios uses - for compatibility */
	
int aha1542_last_mbi_used;
	
int aha1542_last_mbo_used;
	
struct scsi_cmnd *int_cmds[AHA1542_MAILBOXES];
	
struct mailbox mb[2 * AHA1542_MAILBOXES];
	
struct ccb ccb[AHA1542_MAILBOXES];
};



static inline void aha1542_intr_reset(u16 base)
{
	outb(IRST, CONTROL(base));
}

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static inline bool wait_mask(u16 port, u8 mask, u8 allof, u8 noneof, int timeout)
{
	bool delayed = true;

	if (timeout == 0) {
		timeout = 3000000;
		delayed = false;
	}

	while (1) {
		u8 bits = inb(port) & mask;
		if ((bits & allof) == allof && ((bits & noneof) == 0))
			break;
		if (delayed)
			mdelay(1);
		if (--timeout == 0)
			return false;
	}

	return true;
}

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static int aha1542_outb(unsigned int base, u8 val)
{
	if (!wait_mask(STATUS(base), CDF, 0, CDF, 0))
		return 1;
	outb(val, DATA(base));

	return 0;
}

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static int aha1542_out(unsigned int base, u8 *buf, int len)
{
	while (len--) {
		if (!wait_mask(STATUS(base), CDF, 0, CDF, 0))
			return 1;
		outb(*buf++, DATA(base));
	}
	if (!wait_mask(INTRFLAGS(base), INTRMASK, HACC, 0, 0))
		return 1;

	return 0;
}

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/* Only used at boot time, so we do not need to worry about latency as much
   here */



static int aha1542_in(unsigned int base, u8 *buf, int len, int timeout)
{
	while (len--) {
		if (!wait_mask(STATUS(base), DF, DF, 0, timeout))
			return 1;
		*buf++ = inb(DATA(base));
	}
	return 0;
}

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static int makecode(unsigned hosterr, unsigned scsierr)
{
	switch (hosterr) {
	case 0x0:
	case 0xa:		/* Linked command complete without error and linked normally */
	case 0xb:		/* Linked command complete without error, interrupt generated */
		hosterr = 0;
		break;

	case 0x11:		/* Selection time out-The initiator selection or target
                                   reselection was not complete within the SCSI Time out period */
		hosterr = DID_TIME_OUT;
		break;

	case 0x12:		/* Data overrun/underrun-The target attempted to transfer more data
                                   than was allocated by the Data Length field or the sum of the
                                   Scatter / Gather Data Length fields. */

	case 0x13:		/* Unexpected bus free-The target dropped the SCSI BSY at an unexpected time. */

	case 0x15:		/* MBO command was not 00, 01 or 02-The first byte of the CB was
                                   invalid. This usually indicates a software failure. */

	case 0x16:		/* Invalid CCB Operation Code-The first byte of the CCB was invalid.
                                   This usually indicates a software failure. */

	case 0x17:		/* Linked CCB does not have the same LUN-A subsequent CCB of a set
                                   of linked CCB's does not specify the same logical unit number as
                                   the first. */
	case 0x18:		/* Invalid Target Direction received from Host-The direction of a
                                   Target Mode CCB was invalid. */

	case 0x19:		/* Duplicate CCB Received in Target Mode-More than once CCB was
                                   received to service data transfer between the same target LUN
                                   and initiator SCSI ID in the same direction. */

	case 0x1a:		/* Invalid CCB or Segment List Parameter-A segment list with a zero
                                   length segment or invalid segment list boundaries was received.
                                   A CCB parameter was invalid. */
#ifdef DEBUG
		printk("Aha1542: %x %x\n", hosterr, scsierr);
#endif
		hosterr = DID_ERROR;	/* Couldn't find any better */
		break;

	case 0x14:		/* Target bus phase sequence failure-An invalid bus phase or bus
                                   phase sequence was requested by the target. The host adapter
                                   will generate a SCSI Reset Condition, notifying the host with
                                   a SCRD interrupt */
		hosterr = DID_RESET;
		break;
	default:
		printk(KERN_ERR "aha1542: makecode: unknown hoststatus %x\n", hosterr);
		break;
	}
	return scsierr | (hosterr << 16);
}

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static int aha1542_test_port(struct Scsi_Host *sh)
{
	u8 inquiry_result[4];
	int i;

	/* Quick and dirty test for presence of the card. */
	if (inb(STATUS(sh->io_port)) == 0xff)
		return 0;

	/* Reset the adapter. I ought to make a hard reset, but it's not really necessary */

	/* In case some other card was probing here, reset interrupts */
	aha1542_intr_reset(sh->io_port);	/* reset interrupts, so they don't block */

	outb(SRST | IRST /*|SCRST */ , CONTROL(sh->io_port));

	mdelay(20);		/* Wait a little bit for things to settle down. */

	/* Expect INIT and IDLE, any of the others are bad */
	if (!wait_mask(STATUS(sh->io_port), STATMASK, INIT | IDLE, STST | DIAGF | INVDCMD | DF | CDF, 0))
		return 0;

	/* Shouldn't have generated any interrupts during reset */
	if (inb(INTRFLAGS(sh->io_port)) & INTRMASK)
		return 0;

	/* Perform a host adapter inquiry instead so we do not need to set
           up the mailboxes ahead of time */

	aha1542_outb(sh->io_port, CMD_INQUIRY);

	for (i = 0; i < 4; i++) {
		if (!wait_mask(STATUS(sh->io_port), DF, DF, 0, 0))
			return 0;
		inquiry_result[i] = inb(DATA(sh->io_port));
	}

	/* Reading port should reset DF */
	if (inb(STATUS(sh->io_port)) & DF)
		return 0;

	/* When HACC, command is completed, and we're though testing */
	if (!wait_mask(INTRFLAGS(sh->io_port), HACC, HACC, 0, 0))
		return 0;

	/* Clear interrupts */
	outb(IRST, CONTROL(sh->io_port));

	return 1;
}

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static irqreturn_t aha1542_interrupt(int irq, void *dev_id)
{
	struct Scsi_Host *sh = dev_id;
	struct aha1542_hostdata *aha1542 = shost_priv(sh);
	void (*my_done)(struct scsi_cmnd *) = NULL;
	int errstatus, mbi, mbo, mbistatus;
	int number_serviced;
	unsigned long flags;
	struct scsi_cmnd *tmp_cmd;
	int flag;
	struct mailbox *mb = aha1542->mb;
	struct ccb *ccb = aha1542->ccb;

#ifdef DEBUG
	{
		flag = inb(INTRFLAGS(sh->io_port));
		shost_printk(KERN_DEBUG, sh, "aha1542_intr_handle: ");
		if (!(flag & ANYINTR))
			printk("no interrupt?");
		if (flag & MBIF)
			printk("MBIF ");
		if (flag & MBOA)
			printk("MBOF ");
		if (flag & HACC)
			printk("HACC ");
		if (flag & SCRD)
			printk("SCRD ");
		printk("status %02x\n", inb(STATUS(sh->io_port)));
	};
#endif
	number_serviced = 0;

	spin_lock_irqsave(sh->host_lock, flags);
	while (1) {
		flag = inb(INTRFLAGS(sh->io_port));

		/* Check for unusual interrupts.  If any of these happen, we should
                   probably do something special, but for now just printing a message
                   is sufficient.  A SCSI reset detected is something that we really
                   need to deal with in some way. */
		if (flag & ~MBIF) {
			if (flag & MBOA)
				printk("MBOF ");
			if (flag & HACC)
				printk("HACC ");
			if (flag & SCRD)
				printk("SCRD ");
		}
		aha1542_intr_reset(sh->io_port);

		mbi = aha1542->aha1542_last_mbi_used + 1;
		if (mbi >= 2 * AHA1542_MAILBOXES)
			mbi = AHA1542_MAILBOXES;

		do {
			if (mb[mbi].status != 0)
				break;
			mbi++;
			if (mbi >= 2 * AHA1542_MAILBOXES)
				mbi = AHA1542_MAILBOXES;
		} while (mbi != aha1542->aha1542_last_mbi_used);

		if (mb[mbi].status == 0) {
			spin_unlock_irqrestore(sh->host_lock, flags);
			/* Hmm, no mail.  Must have read it the last time around */
			if (!number_serviced)
				shost_printk(KERN_WARNING, sh, "interrupt received, but no mail.\n");
			return IRQ_HANDLED;
		};

		mbo = (scsi2int(mb[mbi].ccbptr) - (isa_virt_to_bus(&ccb[0]))) / sizeof(struct ccb);
		mbistatus = mb[mbi].status;
		mb[mbi].status = 0;
		aha1542->aha1542_last_mbi_used = mbi;

#ifdef DEBUG
		if (ccb[mbo].tarstat | ccb[mbo].hastat)
			shost_printk(KERN_DEBUG, sh, "aha1542_command: returning %x (status %d)\n",
			       ccb[mbo].tarstat + ((int) ccb[mbo].hastat << 16), mb[mbi].status);
#endif

		if (mbistatus == 3)
			continue;	/* Aborted command not found */

#ifdef DEBUG
		shost_printk(KERN_DEBUG, sh, "...done %d %d\n", mbo, mbi);
#endif

		tmp_cmd = aha1542->int_cmds[mbo];

		if (!tmp_cmd || !tmp_cmd->scsi_done) {
			spin_unlock_irqrestore(sh->host_lock, flags);
			shost_printk(KERN_WARNING, sh, "Unexpected interrupt\n");
			shost_printk(KERN_WARNING, sh, "tarstat=%x, hastat=%x idlun=%x ccb#=%d\n", ccb[mbo].tarstat,
			       ccb[mbo].hastat, ccb[mbo].idlun, mbo);
			return IRQ_HANDLED;
		}
		my_done = tmp_cmd->scsi_done;
		kfree(tmp_cmd->host_scribble);
		tmp_cmd->host_scribble = NULL;
		/* Fetch the sense data, and tuck it away, in the required slot.  The
                   Adaptec automatically fetches it, and there is no guarantee that
                   we will still have it in the cdb when we come back */
		if (ccb[mbo].tarstat == 2)
			memcpy(tmp_cmd->sense_buffer, &ccb[mbo].cdb[ccb[mbo].cdblen],
			       SCSI_SENSE_BUFFERSIZE);


		/* is there mail :-) */

		/* more error checking left out here */
		if (mbistatus != 1)
			/* This is surely wrong, but I don't know what's right */
			errstatus = makecode(ccb[mbo].hastat, ccb[mbo].tarstat);
		else
			errstatus = 0;

#ifdef DEBUG
		if (errstatus)
			shost_printk(KERN_DEBUG, sh, "(aha1542 error:%x %x %x) ", errstatus,
			       ccb[mbo].hastat, ccb[mbo].tarstat);
		if (ccb[mbo].tarstat == 2)
			print_hex_dump_bytes("sense: ", DUMP_PREFIX_NONE, &ccb[mbo].cdb[ccb[mbo].cdblen], 12);
		if (errstatus)
			printk("aha1542_intr_handle: returning %6x\n", errstatus);
#endif
		tmp_cmd->result = errstatus;
		aha1542->int_cmds[mbo] = NULL;	/* This effectively frees up the mailbox slot, as
                                                   far as queuecommand is concerned */
		my_done(tmp_cmd);
		number_serviced++;
	};
}

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0.64%
2
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Douglas Gilbert
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1
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static int aha1542_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
{
	struct aha1542_hostdata *aha1542 = shost_priv(sh);
	u8 direction;
	u8 target = cmd->device->id;
	u8 lun = cmd->device->lun;
	unsigned long flags;
	int bufflen = scsi_bufflen(cmd);
	int mbo, sg_count;
	struct mailbox *mb = aha1542->mb;
	struct ccb *ccb = aha1542->ccb;
	struct chain *cptr;

	if (*cmd->cmnd == REQUEST_SENSE) {
		/* Don't do the command - we have the sense data already */
		cmd->result = 0;
		cmd->scsi_done(cmd);
		return 0;
	}
#ifdef DEBUG
	{
		int i = -1;
		if (*cmd->cmnd == READ_10 || *cmd->cmnd == WRITE_10)
			i = xscsi2int(cmd->cmnd + 2);
		else if (*cmd->cmnd == READ_6 || *cmd->cmnd == WRITE_6)
			i = scsi2int(cmd->cmnd + 2);
		shost_printk(KERN_DEBUG, sh, "aha1542_queuecommand: dev %d cmd %02x pos %d len %d",
						target, *cmd->cmnd, i, bufflen);
		print_hex_dump_bytes("command: ", DUMP_PREFIX_NONE, cmd->cmnd, cmd->cmd_len);
	}
#endif
	if (bufflen) {	/* allocate memory before taking host_lock */
		sg_count = scsi_sg_count(cmd);
		cptr = kmalloc(sizeof(*cptr) * sg_count, GFP_KERNEL | GFP_DMA);
		if (!cptr)
			return SCSI_MLQUEUE_HOST_BUSY;
	} else {
		sg_count = 0;
		cptr = NULL;
	}

	/* Use the outgoing mailboxes in a round-robin fashion, because this
           is how the host adapter will scan for them */

	spin_lock_irqsave(sh->host_lock, flags);
	mbo = aha1542->aha1542_last_mbo_used + 1;
	if (mbo >= AHA1542_MAILBOXES)
		mbo = 0;

	do {
		if (mb[mbo].status == 0 && aha1542->int_cmds[mbo] == NULL)
			break;
		mbo++;
		if (mbo >= AHA1542_MAILBOXES)
			mbo = 0;
	} while (mbo != aha1542->aha1542_last_mbo_used);

	if (mb[mbo].status || aha1542->int_cmds[mbo])
		panic("Unable to find empty mailbox for aha1542.\n");

	aha1542->int_cmds[mbo] = cmd;	/* This will effectively prevent someone else from
                                           screwing with this cdb. */

	aha1542->aha1542_last_mbo_used = mbo;

#ifdef DEBUG
	shost_printk(KERN_DEBUG, sh, "Sending command (%d %p)...", mbo, cmd->scsi_done);
#endif

	any2scsi(mb[mbo].ccbptr, isa_virt_to_bus(&ccb[mbo]));	/* This gets trashed for some reason */

	memset(&ccb[mbo], 0, sizeof(struct ccb));

	ccb[mbo].cdblen = cmd->cmd_len;

	direction = 0;
	if (*cmd->cmnd == READ_10 || *cmd->cmnd == READ_6)
		direction = 8;
	else if (*cmd->cmnd == WRITE_10 || *cmd->cmnd == WRITE_6)
		direction = 16;

	memcpy(ccb[mbo].cdb, cmd->cmnd, ccb[mbo].cdblen);

	if (bufflen) {
		struct scatterlist *sg;
		int i;

		ccb[mbo].op = 2;	/* SCSI Initiator Command  w/scatter-gather */
		cmd->host_scribble = (void *)cptr;
		scsi_for_each_sg(cmd, sg, sg_count, i) {
			any2scsi(cptr[i].dataptr, isa_page_to_bus(sg_page(sg))
								+ sg->offset);
			any2scsi(cptr[i].datalen, sg->length);
		};
		any2scsi(ccb[mbo].datalen, sg_count * sizeof(struct chain));
		any2scsi(ccb[mbo].dataptr, isa_virt_to_bus(cptr));
#ifdef DEBUG
		shost_printk(KERN_DEBUG, sh, "cptr %p: ", cptr);
		print_hex_dump_bytes("cptr: ", DUMP_PREFIX_NONE, cptr, 18);
#endif
	} else {
		ccb[mbo].op = 0;	/* SCSI Initiator Command */
		cmd->host_scribble = NULL;
		any2scsi(ccb[mbo].datalen, 0);
		any2scsi(ccb[mbo].dataptr, 0);
	};
	ccb[mbo].idlun = (target & 7) << 5 | direction | (lun & 7);	/*SCSI Target Id */
	ccb[mbo].rsalen = 16;
	ccb[mbo].linkptr[0] = ccb[mbo].linkptr[1] = ccb[mbo].linkptr[2] = 0;
	ccb[mbo].commlinkid = 0;

#ifdef DEBUG
	print_hex_dump_bytes("sending: ", DUMP_PREFIX_NONE, &ccb[mbo], sizeof(ccb[mbo]) - 10);
	printk("aha1542_queuecommand: now waiting for interrupt ");
#endif
	mb[mbo].status = 1;
	aha1542_outb(cmd->device->host->io_port, CMD_START_SCSI);
	spin_unlock_irqrestore(sh->host_lock, flags);

	return 0;
}

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1
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/* Initialize mailboxes */


static void setup_mailboxes(struct Scsi_Host *sh)
{
	struct aha1542_hostdata *aha1542 = shost_priv(sh);
	int i;
	struct mailbox *mb = aha1542->mb;
	struct ccb *ccb = aha1542->ccb;

	u8 mb_cmd[5] = { CMD_MBINIT, AHA1542_MAILBOXES, 0, 0, 0};

	for (i = 0; i < AHA1542_MAILBOXES; i++) {
		mb[i].status = mb[AHA1542_MAILBOXES + i].status = 0;
		any2scsi(mb[i].ccbptr, isa_virt_to_bus(&ccb[i]));
	};
	aha1542_intr_reset(sh->io_port);	/* reset interrupts, so they don't block */
	any2scsi((mb_cmd + 2), isa_virt_to_bus(mb));
	if (aha1542_out(sh->io_port, mb_cmd, 5))
		shost_printk(KERN_ERR, sh, "failed setting up mailboxes\n");
	aha1542_intr_reset(sh->io_port);
}

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static int aha1542_getconfig(struct Scsi_Host *sh)
{
	u8 inquiry_result[3];
	int i;
	i = inb(STATUS(sh->io_port));
	if (i & DF) {
		i = inb(DATA(sh->io_port));
	};
	aha1542_outb(sh->io_port, CMD_RETCONF);
	aha1542_in(sh->io_port, inquiry_result, 3, 0);
	if (!wait_mask(INTRFLAGS(sh->io_port), INTRMASK, HACC, 0, 0))
		shost_printk(KERN_ERR, sh, "error querying board settings\n");
	aha1542_intr_reset(sh->io_port);
	switch (inquiry_result[0]) {
	case 0x80:
		sh->dma_channel = 7;
		break;
	case 0x40:
		sh->dma_channel = 6;
		break;
	case 0x20:
		sh->dma_channel = 5;
		break;
	case 0x01:
		sh->dma_channel = 0;
		break;
	case 0:
		/* This means that the adapter, although Adaptec 1542 compatible, doesn't use a DMA channel.
                   Currently only aware of the BusLogic BT-445S VL-Bus adapter which needs this. */
		sh->dma_channel = 0xFF;
		break;
	default:
		shost_printk(KERN_ERR, sh, "Unable to determine DMA channel.\n");
		return -1;
	};
	switch (inquiry_result[1]) {
	case 0x40:
		sh->irq = 15;
		break;
	case 0x20:
		sh->irq = 14;
		break;
	case 0x8:
		sh->irq = 12;
		break;
	case 0x4:
		sh->irq = 11;
		break;
	case 0x2:
		sh->irq = 10;
		break;
	case 0x1:
		sh->irq = 9;
		break;
	default:
		shost_printk(KERN_ERR, sh, "Unable to determine IRQ level.\n");
		return -1;
	};
	sh->this_id = inquiry_result[2] & 7;
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
200
70.18%
7
50.00%
Ondrej Zary
85
29.82%
7
50.00%
Total
285
100.00%
14
100.00%

/* This function should only be called for 1542C boards - we can detect
   the special firmware settings and unlock the board */



static int aha1542_mbenable(struct Scsi_Host *sh)
{
	static u8 mbenable_cmd[3];
	static u8 mbenable_result[2];
	int retval;

	retval =