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Commit 636b1ec8 authored by Finn Thain's avatar Finn Thain Committed by Martin K. Petersen
Browse files

atari_NCR5380: Reset bus on driver initialization if required 



Merge the bus reset code from NCR5380.c into atari_NCR5380.c. This allows
for removal of a lot of duplicated code conditional on the RESET_BOOT
macro (in the next patch).

The atari_NCR5380.c fork lacks the do_reset() and NCR5380_poll_politely()
routines from NCR5380.c, so introduce them. They are indispensible. Keep
the two implementations in sync.

Signed-off-by: default avatarFinn Thain <fthain@telegraphics.com.au>
Reviewed-by: default avatarHannes Reinecke <hare@suse.com>
Tested-by: default avatarOndrej Zary <linux@rainbow-software.org>
Tested-by: default avatarMichael Schmitz <schmitzmic@gmail.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 4d8c08c7

drivers/scsi/NCR5380.c

+21 −12
Original line number Diff line number Diff line
@@ -838,19 +838,20 @@ static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance) 
		case 1:

		case 3:

		case 5:

			printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);

			NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);

			shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n");

			NCR5380_poll_politely(instance,

			                      STATUS_REG, SR_BSY, 0, 5 * HZ);

			break;

		case 2:

			printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);

			shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");

			do_abort(instance);

			break;

		case 4:

			printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);

			shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n");

			do_reset(instance);

			break;

		case 6:

			printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);

			shost_printk(KERN_ERR, instance, "bus locked solid\n");

			return -ENXIO;

		}

	}
@@ -1580,20 +1581,28 @@ static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase 


/**

 * do_reset - issue a reset command

 *	@host: adapter to reset

 * @instance: adapter to reset

 *

 * Issue a reset sequence to the NCR5380 and try and get the bus

 * back into sane shape.

 *

 *	Locks: caller holds queue lock

 * This clears the reset interrupt flag because there may be no handler for

 * it. When the driver is initialized, the NCR5380_intr() handler has not yet

 * been installed. And when in EH we may have released the ST DMA interrupt.

 */

 

static void do_reset(struct Scsi_Host *instance)

{

	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));

	unsigned long flags;



	local_irq_save(flags);

	NCR5380_write(TARGET_COMMAND_REG,

	              PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);

	udelay(25);

	udelay(50);

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);

	local_irq_restore(flags);

}



/*

drivers/scsi/atari_NCR5380.c

+113 −0
Original line number Diff line number Diff line
@@ -234,6 +234,9 @@ 
#define	HOSTNO		instance->host_no

#define	H_NO(cmd)	(cmd)->device->host->host_no



static int do_abort(struct Scsi_Host *);

static void do_reset(struct Scsi_Host *);



#ifdef SUPPORT_TAGS



/*
@@ -475,6 +478,47 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd) 
	}

}



/**

 * NCR5380_poll_politely - wait for NCR5380 status bits

 * @instance: controller to poll

 * @reg: 5380 register to poll

 * @bit: Bitmask to check

 * @val: Value required to exit

 *

 * Polls the NCR5380 in a reasonably efficient manner waiting for

 * an event to occur, after a short quick poll we begin giving the

 * CPU back in non IRQ contexts

 *

 * Returns the value of the register or a negative error code.

 */



static int NCR5380_poll_politely(struct Scsi_Host *instance,

                                 int reg, int bit, int val, int t)

{

	int n = 500;

	unsigned long end = jiffies + t;

	int r;



	while (n-- > 0) {

		r = NCR5380_read(reg);

		if ((r & bit) == val)

			return 0;

		cpu_relax();

	}



	/* t time yet ? */

	while (time_before(jiffies, end)) {

		r = NCR5380_read(reg);

		if ((r & bit) == val)

			return 0;

		if (!in_interrupt())

			cond_resched();

		else

			cpu_relax();

	}

	return -ETIMEDOUT;

}



#include <linux/delay.h>



#if NDEBUG
@@ -800,6 +844,49 @@ static int __init NCR5380_init(struct Scsi_Host *instance, int flags) 
	return 0;

}



/**

 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.

 * @instance: adapter to check

 *

 * If the system crashed, it may have crashed with a connected target and

 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the

 * currently established nexus, which we know nothing about. Failing that

 * do a bus reset.

 *

 * Note that a bus reset will cause the chip to assert IRQ.

 *

 * Returns 0 if successful, otherwise -ENXIO.

 */



static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance)

{

	int pass;



	for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {

		switch (pass) {

		case 1:

		case 3:

		case 5:

			shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n");

			NCR5380_poll_politely(instance,

			                      STATUS_REG, SR_BSY, 0, 5 * HZ);

			break;

		case 2:

			shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");

			do_abort(instance);

			break;

		case 4:

			shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n");

			do_reset(instance);

			break;

		case 6:

			shost_printk(KERN_ERR, instance, "bus locked solid\n");

			return -ENXIO;

		}

	}

	return 0;

}



/**

 * NCR5380_exit - remove an NCR5380

 * @instance: adapter to remove
@@ -1741,6 +1828,32 @@ static int NCR5380_transfer_pio(struct Scsi_Host *instance, 
		return -1;

}



/**

 * do_reset - issue a reset command

 * @instance: adapter to reset

 *

 * Issue a reset sequence to the NCR5380 and try and get the bus

 * back into sane shape.

 *

 * This clears the reset interrupt flag because there may be no handler for

 * it. When the driver is initialized, the NCR5380_intr() handler has not yet

 * been installed. And when in EH we may have released the ST DMA interrupt.

 */



static void do_reset(struct Scsi_Host *instance)

{

	unsigned long flags;



	local_irq_save(flags);

	NCR5380_write(TARGET_COMMAND_REG,

	              PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);

	udelay(50);

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);

	local_irq_restore(flags);

}



/*

 * Function : do_abort (Scsi_Host *host)

 *