Commit aa2731ad authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

libata: separate out ata_wait_ready() and implement ata_wait_after_reset() 



Factor out waiting logic (which is common to all ATA controllers) from
ata_sff_wait_ready() into ata_wait_ready().  ata_wait_ready() takes
@check_ready function pointer and uses it to poll for readiness.  This
allows non-SFF controllers to use ata_wait_ready() to wait for link
readiness.

This patch also implements ata_wait_after_reset() - generic version of
ata_sff_wait_after_reset() - using ata_wait_ready().

ata_sff_wait_ready() is reimplemented using ata_wait_ready() and
ata_sff_check_ready().  Functionality remains the same.

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
parent 705e76be

drivers/ata/libata-core.c

+98 −0
Original line number Diff line number Diff line
@@ -3310,6 +3310,103 @@ int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev) 
	return rc;

}



/**

 *	ata_wait_ready - wait for link to become ready

 *	@link: link to be waited on

 *	@deadline: deadline jiffies for the operation

 *	@check_ready: callback to check link readiness

 *

 *	Wait for @link to become ready.  @check_ready should return

 *	positive number if @link is ready, 0 if it isn't, -ENODEV if

 *	link doesn't seem to be occupied, other errno for other error

 *	conditions.

 *

 *	Transient -ENODEV conditions are allowed for

 *	ATA_TMOUT_FF_WAIT.

 *

 *	LOCKING:

 *	EH context.

 *

 *	RETURNS:

 *	0 if @linke is ready before @deadline; otherwise, -errno.

 */

int ata_wait_ready(struct ata_link *link, unsigned long deadline,

		   int (*check_ready)(struct ata_link *link))

{

	unsigned long start = jiffies;

	unsigned long nodev_deadline = start + ATA_TMOUT_FF_WAIT;

	int warned = 0;



	if (time_after(nodev_deadline, deadline))

		nodev_deadline = deadline;



	while (1) {

		unsigned long now = jiffies;

		int ready, tmp;



		ready = tmp = check_ready(link);

		if (ready > 0)

			return 0;



		/* -ENODEV could be transient.  Ignore -ENODEV if link

		 * is online.  Also, some SATA devices take a long

		 * time to clear 0xff after reset.  For example,

		 * HHD424020F7SV00 iVDR needs >= 800ms while Quantum

		 * GoVault needs even more than that.  Wait for

		 * ATA_TMOUT_FF_WAIT on -ENODEV if link isn't offline.

		 *

		 * Note that some PATA controllers (pata_ali) explode

		 * if status register is read more than once when

		 * there's no device attached.

		 */

		if (ready == -ENODEV) {

			if (ata_link_online(link))

				ready = 0;

			else if ((link->ap->flags & ATA_FLAG_SATA) &&

				 !ata_link_offline(link) &&

				 time_before(now, nodev_deadline))

				ready = 0;

		}



		if (ready)

			return ready;

		if (time_after(now, deadline))

			return -EBUSY;



		if (!warned && time_after(now, start + 5 * HZ) &&

		    (deadline - now > 3 * HZ)) {

			ata_link_printk(link, KERN_WARNING,

				"link is slow to respond, please be patient "

				"(ready=%d)\n", tmp);

			warned = 1;

		}



		msleep(50);

	}

}



/**

 *	ata_wait_after_reset - wait for link to become ready after reset

 *	@link: link to be waited on

 *	@deadline: deadline jiffies for the operation

 *	@check_ready: callback to check link readiness

 *

 *	Wait for @link to become ready after reset.

 *

 *	LOCKING:

 *	EH context.

 *

 *	RETURNS:

 *	0 if @linke is ready before @deadline; otherwise, -errno.

 */

extern int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,

				int (*check_ready)(struct ata_link *link))

{

	msleep(ATA_WAIT_AFTER_RESET_MSECS);



	return ata_wait_ready(link, deadline, check_ready);

}



/**

 *	sata_link_debounce - debounce SATA phy status

 *	@link: ATA link to debounce SATA phy status for
@@ -6075,6 +6172,7 @@ EXPORT_SYMBOL_GPL(ata_noop_qc_prep); 
EXPORT_SYMBOL_GPL(ata_port_probe);

EXPORT_SYMBOL_GPL(ata_dev_disable);

EXPORT_SYMBOL_GPL(sata_set_spd);

EXPORT_SYMBOL_GPL(ata_wait_after_reset);

EXPORT_SYMBOL_GPL(sata_link_debounce);

EXPORT_SYMBOL_GPL(sata_link_resume);

EXPORT_SYMBOL_GPL(ata_std_prereset);

drivers/ata/libata-sff.c

+12 −50
Original line number Diff line number Diff line
@@ -308,6 +308,17 @@ int ata_sff_busy_sleep(struct ata_port *ap, 
	return 0;

}



static int ata_sff_check_ready(struct ata_link *link)

{

	u8 status = link->ap->ops->sff_check_status(link->ap);



	if (!(status & ATA_BUSY))

		return 1;

	if (status == 0xff)

		return -ENODEV;

	return 0;

}



/**

 *	ata_sff_wait_ready - sleep until BSY clears, or timeout

 *	@link: SFF link to wait ready status for
@@ -324,56 +335,7 @@ int ata_sff_busy_sleep(struct ata_port *ap, 
 */

int ata_sff_wait_ready(struct ata_link *link, unsigned long deadline)

{

	struct ata_port *ap = link->ap;

	unsigned long start = jiffies;

	unsigned long nodev_deadline = start + ATA_TMOUT_FF_WAIT;

	int warned = 0;



	if (time_after(nodev_deadline, deadline))

		nodev_deadline = deadline;



	while (1) {

		u8 status = ap->ops->sff_check_status(ap);

		unsigned long now = jiffies;



		if (!(status & ATA_BUSY))

			return 0;



		/* No device status could be transient.  Ignore it if

		 * link is online.  Also, some SATA devices take a

		 * long time to clear 0xff after reset.  For example,

		 * HHD424020F7SV00 iVDR needs >= 800ms while Quantum

		 * GoVault needs even more than that.  Wait for

		 * ATA_TMOUT_FF_WAIT on -ENODEV if link isn't offline.

		 *

		 * Note that some PATA controllers (pata_ali) explode

		 * if status register is read more than once when

		 * there's no device attached.

		 */

		if (status == 0xff) {

			if (ata_link_online(link))

				status = ATA_BUSY;

			else if ((link->ap->flags & ATA_FLAG_SATA) &&

				 !ata_link_offline(link) &&

				 time_before(now, nodev_deadline))

				status = ATA_BUSY;

			if (status == 0xff)

				return -ENODEV;

		}



		if (time_after(now, deadline))

			return -EBUSY;



		if (!warned && time_after(now, start + 5 * HZ) &&

		    (deadline - now > 3 * HZ)) {

			ata_link_printk(link, KERN_WARNING,

				"link is slow to respond, please be patient "

				"(Status 0x%x)\n", status);

			warned = 1;

		}



		msleep(50);

	}

	return ata_wait_ready(link, deadline, ata_sff_check_ready);

}



/**

drivers/ata/libata.h

+2 −0
Original line number Diff line number Diff line
@@ -81,6 +81,8 @@ extern unsigned ata_exec_internal_sg(struct ata_device *dev, 
				     int dma_dir, struct scatterlist *sg,

				     unsigned int n_elem, unsigned long timeout);

extern unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd);

extern int ata_wait_ready(struct ata_link *link, unsigned long deadline,

			  int (*check_ready)(struct ata_link *link));

extern int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,

			   unsigned int flags, u16 *id);

extern int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags);

include/linux/libata.h

+2 −0
Original line number Diff line number Diff line
@@ -837,6 +837,8 @@ extern void sata_print_link_status(struct ata_link *link); 
extern void ata_port_probe(struct ata_port *);

extern int sata_set_spd(struct ata_link *link);

extern int ata_std_prereset(struct ata_link *link, unsigned long deadline);

extern int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,

				int (*check_ready)(struct ata_link *link));

extern int sata_link_debounce(struct ata_link *link,

			const unsigned long *params, unsigned long deadline);

extern int sata_link_resume(struct ata_link *link, const unsigned long *params,

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