wd7000.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,669 行 · 第 1/4 页

/*
 * 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.
 */

/*
 *  WD7000-specific scatter/gather element structure
 */
typedef struct sgb {
	unchar len[3];
	unchar ptr[3];		/* Also SCSI-style - MSB first */
} Sgb;

typedef struct scb {		/* Command Control Block 5.4.1               */
	unchar op;		/* Command Control Block Operation Code      */
	unchar idlun;		/* op=0,2:Target Id, op=1:Initiator Id       */
	/* Outbound data transfer, length is checked */
	/* Inbound data transfer, length is checked  */
	/* Logical Unit Number                       */
	unchar cdb[12];		/* SCSI Command Block                        */
	volatile unchar status;	/* SCSI Return Status                        */
	volatile unchar vue;	/* Vendor Unique Error Code                  */
	unchar maxlen[3];	/* Maximum Data Transfer Length              */
	unchar dataptr[3];	/* SCSI Data Block Pointer                   */
	unchar linkptr[3];	/* Next Command Link Pointer                 */
	unchar direc;		/* Transfer Direction                        */
	unchar reserved2[6];	/* SCSI Command Descriptor Block             */
	/* end of hardware SCB                       */
	struct scsi_cmnd *SCpnt;/* scsi_cmnd using this SCB                  */
	Sgb sgb[WD7000_SG];	/* Scatter/gather list for this SCB          */
	Adapter *host;		/* host adapter                              */
	struct scb *next;	/* for lists of scbs                         */
} Scb;

/*
 *  This driver is written to allow host-only commands to be executed.
 *  These use a 16-byte block called an ICB.  The format is extended by the
 *  driver to 18 bytes, to support the status returned in the ICMB and
 *  an execution phase code.
 *
 *  There are other formats besides these; these are the ones I've tried
 *  to use.  Formats for some of the defined ICB opcodes are not defined
 *  (notably, get/set unsolicited interrupt status) in my copy of the OEM
 *  manual, and others are ambiguous/hard to follow.
 */
#define ICB_OP_MASK           0x80	/* distinguishes scbs from icbs        */
#define ICB_OP_OPEN_RBUF      0x80	/* open receive buffer                 */
#define ICB_OP_RECV_CMD       0x81	/* receive command from initiator      */
#define ICB_OP_RECV_DATA      0x82	/* receive data from initiator         */
#define ICB_OP_RECV_SDATA     0x83	/* receive data with status from init. */
#define ICB_OP_SEND_DATA      0x84	/* send data with status to initiator  */
#define ICB_OP_SEND_STAT      0x86	/* send command status to initiator    */
					/* 0x87 is reserved                    */
#define ICB_OP_READ_INIT      0x88	/* read initialization bytes           */
#define ICB_OP_READ_ID        0x89	/* read adapter's SCSI ID              */
#define ICB_OP_SET_UMASK      0x8A	/* set unsolicited interrupt mask      */
#define ICB_OP_GET_UMASK      0x8B	/* read unsolicited interrupt mask     */
#define ICB_OP_GET_REVISION   0x8C	/* read firmware revision level        */
#define ICB_OP_DIAGNOSTICS    0x8D	/* execute diagnostics                 */
#define ICB_OP_SET_EPARMS     0x8E	/* set execution parameters            */
#define ICB_OP_GET_EPARMS     0x8F	/* read execution parameters           */

typedef struct icbRecvCmd {
	unchar op;
	unchar IDlun;		/* Initiator SCSI ID/lun     */
	unchar len[3];		/* command buffer length     */
	unchar ptr[3];		/* command buffer address    */
	unchar rsvd[7];		/* reserved                  */
	volatile unchar vue;	/* vendor-unique error code  */
	volatile unchar status;	/* returned (icmb) status    */
	volatile unchar phase;	/* used by interrupt handler */
} IcbRecvCmd;

typedef struct icbSendStat {
	unchar op;
	unchar IDlun;		/* Target SCSI ID/lun                  */
	unchar stat;		/* (outgoing) completion status byte 1 */
	unchar rsvd[12];	/* reserved                            */
	volatile unchar vue;	/* vendor-unique error code            */
	volatile unchar status;	/* returned (icmb) status              */
	volatile unchar phase;	/* used by interrupt handler           */
} IcbSendStat;

typedef struct icbRevLvl {
	unchar op;
	volatile unchar primary;	/* primary revision level (returned)   */
	volatile unchar secondary;	/* secondary revision level (returned) */
	unchar rsvd[12];	/* reserved                            */
	volatile unchar vue;	/* vendor-unique error code            */
	volatile unchar status;	/* returned (icmb) status              */
	volatile unchar phase;	/* used by interrupt handler           */
} IcbRevLvl;

typedef struct icbUnsMask {	/* I'm totally guessing here */
	unchar op;
	volatile unchar mask[14];	/* mask bits                 */
#if 0
	unchar rsvd[12];	/* reserved                  */
#endif
	volatile unchar vue;	/* vendor-unique error code  */
	volatile unchar status;	/* returned (icmb) status    */
	volatile unchar phase;	/* used by interrupt handler */
} IcbUnsMask;

typedef struct icbDiag {
	unchar op;
	unchar type;		/* diagnostics type code (0-3) */
	unchar len[3];		/* buffer length               */
	unchar ptr[3];		/* buffer address              */
	unchar rsvd[7];		/* reserved                    */
	volatile unchar vue;	/* vendor-unique error code    */
	volatile unchar status;	/* returned (icmb) status      */
	volatile unchar phase;	/* used by interrupt handler   */
} IcbDiag;

#define ICB_DIAG_POWERUP   0	/* Power-up diags only       */
#define ICB_DIAG_WALKING   1	/* walking 1's pattern       */
#define ICB_DIAG_DMA       2	/* DMA - system memory diags */
#define ICB_DIAG_FULL      3	/* do both 1 & 2             */

typedef struct icbParms {
	unchar op;
	unchar rsvd1;		/* reserved                  */
	unchar len[3];		/* parms buffer length       */
	unchar ptr[3];		/* parms buffer address      */
	unchar idx[2];		/* index (MSB-LSB)           */
	unchar rsvd2[5];	/* reserved                  */
	volatile unchar vue;	/* vendor-unique error code  */
	volatile unchar status;	/* returned (icmb) status    */
	volatile unchar phase;	/* used by interrupt handler */
} IcbParms;

typedef struct icbAny {
	unchar op;
	unchar data[14];	/* format-specific data      */
	volatile unchar vue;	/* vendor-unique error code  */
	volatile unchar status;	/* returned (icmb) status    */
	volatile unchar phase;	/* used by interrupt handler */
} IcbAny;

typedef union icb {
	unchar op;		/* ICB opcode                     */
	IcbRecvCmd recv_cmd;	/* format for receive command     */
	IcbSendStat send_stat;	/* format for send status         */
	IcbRevLvl rev_lvl;	/* format for get revision level  */
	IcbDiag diag;		/* format for execute diagnostics */
	IcbParms eparms;	/* format for get/set exec parms  */
	IcbAny icb;		/* generic format                 */
	unchar data[18];
} Icb;

#ifdef MODULE
static char *wd7000;
MODULE_PARM(wd7000, "s");
#endif

/*
 *  Driver SCB structure pool.
 *
 *  The SCBs declared here are shared by all host adapters; hence, this
 *  structure is not part of the Adapter structure.
 */
static Scb scbs[MAX_SCBS];
static Scb *scbfree;		/* free list         */
static int freescbs = MAX_SCBS;	/* free list counter */
static spinlock_t scbpool_lock;	/* guards the scb free list and count */

/*
 *  END of data/declarations - code follows.
 */
static void __init setup_error(char *mesg, int *ints)
{
	if (ints[0] == 3)
		printk(KERN_ERR "wd7000_setup: \"wd7000=%d,%d,0x%x\" -> %s\n", ints[1], ints[2], ints[3], mesg);
	else if (ints[0] == 4)
		printk(KERN_ERR "wd7000_setup: \"wd7000=%d,%d,0x%x,%d\" -> %s\n", ints[1], ints[2], ints[3], ints[4], mesg);
	else
		printk(KERN_ERR "wd7000_setup: \"wd7000=%d,%d,0x%x,%d,%d\" -> %s\n", ints[1], ints[2], ints[3], ints[4], ints[5], mesg);
}


/*
 * Note: You can now set these options from the kernel's "command line".
 * The syntax is:
 *
 *     wd7000=<IRQ>,<DMA>,<IO>[,<BUS_ON>[,<BUS_OFF>]]
 *
 * , where BUS_ON and BUS_OFF are in nanoseconds. BIOS default values
 * are 8000ns for BUS_ON and 1875ns for BUS_OFF.
 * eg:
 *     wd7000=7,6,0x350
 *
 * will configure the driver for a WD-7000 controller
 * using IRQ 15 with a DMA channel 6, at IO base address 0x350.
 */
static int __init wd7000_setup(char *str)
{
	static short wd7000_card_num;	/* .bss will zero this */
	short i;
	int ints[6];

	(void) get_options(str, ARRAY_SIZE(ints), ints);

	if (wd7000_card_num >= NUM_CONFIGS) {
		printk(KERN_ERR "%s: Too many \"wd7000=\" configurations in " "command line!\n", __FUNCTION__);
		return 0;
	}

	if ((ints[0] < 3) || (ints[0] > 5)) {
		printk(KERN_ERR "%s: Error in command line!  " "Usage: wd7000=<IRQ>,<DMA>,IO>[,<BUS_ON>" "[,<BUS_OFF>]]\n", __FUNCTION__);
	} else {
		for (i = 0; i < NUM_IRQS; i++)
			if (ints[1] == wd7000_irq[i])
				break;

		if (i == NUM_IRQS) {
			setup_error("invalid IRQ.", ints);
			return 0;
		} else
			configs[wd7000_card_num].irq = ints[1];

		for (i = 0; i < NUM_DMAS; i++)
			if (ints[2] == wd7000_dma[i])
				break;

		if (i == NUM_DMAS) {
			setup_error("invalid DMA channel.", ints);
			return 0;
		} else
			configs[wd7000_card_num].dma = ints[2];

		for (i = 0; i < NUM_IOPORTS; i++)
			if (ints[3] == wd7000_iobase[i])
				break;

		if (i == NUM_IOPORTS) {
			setup_error("invalid I/O base address.", ints);
			return 0;
		} else
			configs[wd7000_card_num].iobase = ints[3];

		if (ints[0] > 3) {
			if ((ints[4] < 500) || (ints[4] > 31875)) {
				setup_error("BUS_ON value is out of range (500" " to 31875 nanoseconds)!", ints);
				configs[wd7000_card_num].bus_on = BUS_ON;
			} else
				configs[wd7000_card_num].bus_on = ints[4] / 125;
		} else
			configs[wd7000_card_num].bus_on = BUS_ON;

		if (ints[0] > 4) {
			if ((ints[5] < 500) || (ints[5] > 31875)) {
				setup_error("BUS_OFF value is out of range (500" " to 31875 nanoseconds)!", ints);
				configs[wd7000_card_num].bus_off = BUS_OFF;
			} else
				configs[wd7000_card_num].bus_off = ints[5] / 125;
		} else
			configs[wd7000_card_num].bus_off = BUS_OFF;

		if (wd7000_card_num) {
			for (i = 0; i < (wd7000_card_num - 1); i++) {
				int j = i + 1;

				for (; j < wd7000_card_num; j++)
					if (configs[i].irq == configs[j].irq) {
						setup_error("duplicated IRQ!", ints);
						return 0;
					}
				if (configs[i].dma == configs[j].dma) {
					setup_error("duplicated DMA " "channel!", ints);
					return 0;
				}
				if (configs[i].iobase == configs[j].iobase) {
					setup_error("duplicated I/O " "base address!", ints);
					return 0;
				}
			}
		}

		dprintk(KERN_DEBUG "wd7000_setup: IRQ=%d, DMA=%d, I/O=0x%x, "
			"BUS_ON=%dns, BUS_OFF=%dns\n", configs[wd7000_card_num].irq, configs[wd7000_card_num].dma, configs[wd7000_card_num].iobase, configs[wd7000_card_num].bus_on * 125, configs[wd7000_card_num].bus_off * 125);

		wd7000_card_num++;
	}
	return 1;
}

__setup("wd7000=", wd7000_setup);

static inline void any2scsi(unchar * scsi, int any)
{
	*scsi++ = (unsigned)any >> 16;
	*scsi++ = (unsigned)any >> 8;
	*scsi++ = any;
}

static inline int scsi2int(unchar * scsi)
{
	return (scsi[0] << 16) | (scsi[1] << 8) | scsi[2];
}

static inline void wd7000_enable_intr(Adapter * host)
{
	host->control |= INT_EN;
	outb(host->control, host->iobase + ASC_CONTROL);
}


static inline void wd7000_enable_dma(Adapter * host)
{
	unsigned long flags;
	host->control |= DMA_EN;
	outb(host->control, host->iobase + ASC_CONTROL);

	flags = claim_dma_lock();
	set_dma_mode(host->dma, DMA_MODE_CASCADE);
	enable_dma(host->dma);
	release_dma_lock(flags);

}


#define WAITnexttimeout 200	/* 2 seconds */

static inline short WAIT(unsigned port, unsigned mask, unsigned allof, unsigned noneof)
{
	unsigned WAITbits;
	unsigned long WAITtimeout = jiffies + WAITnexttimeout;

	while (time_before_eq(jiffies, WAITtimeout)) {
		WAITbits = inb(port) & mask;

		if (((WAITbits & allof) == allof) && ((WAITbits & noneof) == 0))
			return (0);
	}

	return (1);
}


static inline int command_out(Adapter * host, unchar * cmd, int len)
{
	if (!WAIT(host->iobase + ASC_STAT, ASC_STATMASK, CMD_RDY, 0)) {
		while (len--) {
			do {
				outb(*cmd, host->iobase + ASC_COMMAND);
				WAIT(host->iobase + ASC_STAT, ASC_STATMASK, CMD_RDY, 0);
			} while (inb(host->iobase + ASC_STAT) & CMD_REJ);

			cmd++;
		}

		return (1);
	}

	printk(KERN_WARNING "wd7000 command_out: WAIT failed(%d)\n", len + 1);

	return (0);
}


/*
 *  This version of alloc_scbs is in preparation for supporting multiple
 *  commands per lun and command chaining, by queueing pending commands.
 *  We will need to allocate Scbs in blocks since they will wait to be
 *  executed so there is the possibility of deadlock otherwise.
 *  Also, to keep larger requests from being starved by smaller requests,
 *  we limit access to this routine with an internal busy flag, so that
 *  the satisfiability of a request is not dependent on the size of the
 *  request.
 */
static inline Scb *alloc_scbs(struct Scsi_Host *host, int needed)
{
	Scb *scb, *p = NULL;
	unsigned long flags;
	unsigned long timeout = jiffies + WAITnexttimeout;
	unsigned long now;
	int i;

	if (needed <= 0)
		return (NULL);	/* sanity check */

	spin_unlock_irq(host->host_lock);

      retry:
	while (freescbs < needed) {
		timeout = jiffies + WAITnexttimeout;
		do {
			/* FIXME: can we actually just yield here ?? */
			for (now = jiffies; now == jiffies;)
				cpu_relax();	/* wait a jiffy */
		} while (freescbs < needed && time_before_eq(jiffies, timeout));
		/*
		 *  If we get here with enough free Scbs, we can take them.
		 *  Otherwise, we timed out and didn't get enough.
		 */
		if (freescbs < needed) {
			printk(KERN_ERR "wd7000: can't get enough free SCBs.\n");