libata-pmp.c

linux 内核源代码

	spin_lock_irqsave(ap->lock, flags);
	WARN_ON(ap->nr_pmp_links);
	ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
	spin_unlock_irqrestore(ap->lock, flags);

	sata_pmp_quirks(ap);

	if (ap->ops->pmp_attach)
		ap->ops->pmp_attach(ap);

	ata_port_for_each_link(tlink, ap)
		sata_link_init_spd(tlink);

	ata_acpi_associate_sata_port(ap);

	return 0;

 fail:
	link->pmp = 0;
	return rc;
}

/**
 *	sata_pmp_detach - detach a SATA PMP device
 *	@dev: SATA PMP device to detach
 *
 *	Detach SATA PMP device @dev.  This function is also
 *	responsible for deconfiguring PMP links.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 */
static void sata_pmp_detach(struct ata_device *dev)
{
	struct ata_link *link = dev->link;
	struct ata_port *ap = link->ap;
	struct ata_link *tlink;
	unsigned long flags;

	ata_dev_printk(dev, KERN_INFO, "Port Multiplier detaching\n");

	WARN_ON(!ata_is_host_link(link) || dev->devno ||
		link->pmp != SATA_PMP_CTRL_PORT);

	if (ap->ops->pmp_detach)
		ap->ops->pmp_detach(ap);

	ata_port_for_each_link(tlink, ap)
		ata_eh_detach_dev(tlink->device);

	spin_lock_irqsave(ap->lock, flags);
	ap->nr_pmp_links = 0;
	link->pmp = 0;
	spin_unlock_irqrestore(ap->lock, flags);

	ata_acpi_associate_sata_port(ap);
}

/**
 *	sata_pmp_same_pmp - does new GSCR matches the configured PMP?
 *	@dev: PMP device to compare against
 *	@new_gscr: GSCR block of the new device
 *
 *	Compare @new_gscr against @dev and determine whether @dev is
 *	the PMP described by @new_gscr.
 *
 *	LOCKING:
 *	None.
 *
 *	RETURNS:
 *	1 if @dev matches @new_gscr, 0 otherwise.
 */
static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
{
	const u32 *old_gscr = dev->gscr;
	u16 old_vendor, new_vendor, old_devid, new_devid;
	int old_nr_ports, new_nr_ports;

	old_vendor = sata_pmp_gscr_vendor(old_gscr);
	new_vendor = sata_pmp_gscr_vendor(new_gscr);
	old_devid = sata_pmp_gscr_devid(old_gscr);
	new_devid = sata_pmp_gscr_devid(new_gscr);
	old_nr_ports = sata_pmp_gscr_ports(old_gscr);
	new_nr_ports = sata_pmp_gscr_ports(new_gscr);

	if (old_vendor != new_vendor) {
		ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
			       "vendor mismatch '0x%x' != '0x%x'\n",
			       old_vendor, new_vendor);
		return 0;
	}

	if (old_devid != new_devid) {
		ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
			       "device ID mismatch '0x%x' != '0x%x'\n",
			       old_devid, new_devid);
		return 0;
	}

	if (old_nr_ports != new_nr_ports) {
		ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
			       "nr_ports mismatch '0x%x' != '0x%x'\n",
			       old_nr_ports, new_nr_ports);
		return 0;
	}

	return 1;
}

/**
 *	sata_pmp_revalidate - revalidate SATA PMP
 *	@dev: PMP device to revalidate
 *	@new_class: new class code
 *
 *	Re-read GSCR block and make sure @dev is still attached to the
 *	port and properly configured.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
{
	struct ata_link *link = dev->link;
	struct ata_port *ap = link->ap;
	u32 *gscr = (void *)ap->sector_buf;
	int rc;

	DPRINTK("ENTER\n");

	ata_eh_about_to_do(link, NULL, ATA_EH_REVALIDATE);

	if (!ata_dev_enabled(dev)) {
		rc = -ENODEV;
		goto fail;
	}

	/* wrong class? */
	if (ata_class_enabled(new_class) && new_class != ATA_DEV_PMP) {
		rc = -ENODEV;
		goto fail;
	}

	/* read GSCR */
	rc = sata_pmp_read_gscr(dev, gscr);
	if (rc)
		goto fail;

	/* is the pmp still there? */
	if (!sata_pmp_same_pmp(dev, gscr)) {
		rc = -ENODEV;
		goto fail;
	}

	memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);

	rc = sata_pmp_configure(dev, 0);
	if (rc)
		goto fail;

	ata_eh_done(link, NULL, ATA_EH_REVALIDATE);

	DPRINTK("EXIT, rc=0\n");
	return 0;

 fail:
	ata_dev_printk(dev, KERN_ERR,
		       "PMP revalidation failed (errno=%d)\n", rc);
	DPRINTK("EXIT, rc=%d\n", rc);
	return rc;
}

/**
 *	sata_pmp_revalidate_quick - revalidate SATA PMP quickly
 *	@dev: PMP device to revalidate
 *
 *	Make sure the attached PMP is accessible.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
static int sata_pmp_revalidate_quick(struct ata_device *dev)
{
	unsigned int err_mask;
	u32 prod_id;

	err_mask = sata_pmp_read(dev->link, SATA_PMP_GSCR_PROD_ID, &prod_id);
	if (err_mask) {
		ata_dev_printk(dev, KERN_ERR, "failed to read PMP product ID "
			       "(Emask=0x%x)\n", err_mask);
		return -EIO;
	}

	if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
		ata_dev_printk(dev, KERN_ERR, "PMP product ID mismatch\n");
		/* something weird is going on, request full PMP recovery */
		return -EIO;
	}

	return 0;
}

/**
 *	sata_pmp_eh_recover_pmp - recover PMP
 *	@ap: ATA port PMP is attached to
 *	@prereset: prereset method (can be NULL)
 *	@softreset: softreset method
 *	@hardreset: hardreset method
 *	@postreset: postreset method (can be NULL)
 *
 *	Recover PMP attached to @ap.  Recovery procedure is somewhat
 *	similar to that of ata_eh_recover() except that reset should
 *	always be performed in hard->soft sequence and recovery
 *	failure results in PMP detachment.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno on failure.
 */
static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
		ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
		ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
{
	struct ata_link *link = &ap->link;
	struct ata_eh_context *ehc = &link->eh_context;
	struct ata_device *dev = link->device;
	int tries = ATA_EH_PMP_TRIES;
	int detach = 0, rc = 0;
	int reval_failed = 0;

	DPRINTK("ENTER\n");

	if (dev->flags & ATA_DFLAG_DETACH) {
		detach = 1;
		goto fail;
	}

 retry:
	ehc->classes[0] = ATA_DEV_UNKNOWN;

	if (ehc->i.action & ATA_EH_RESET_MASK) {
		struct ata_link *tlink;

		ata_eh_freeze_port(ap);

		/* reset */
		ehc->i.action = ATA_EH_HARDRESET;
		rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
				  postreset);
		if (rc) {
			ata_link_printk(link, KERN_ERR,
					"failed to reset PMP, giving up\n");
			goto fail;
		}

		ata_eh_thaw_port(ap);

		/* PMP is reset, SErrors cannot be trusted, scan all */
		ata_port_for_each_link(tlink, ap)
			ata_ehi_schedule_probe(&tlink->eh_context.i);
	}

	/* If revalidation is requested, revalidate and reconfigure;
	 * otherwise, do quick revalidation.
	 */
	if (ehc->i.action & ATA_EH_REVALIDATE)
		rc = sata_pmp_revalidate(dev, ehc->classes[0]);
	else
		rc = sata_pmp_revalidate_quick(dev);

	if (rc) {
		tries--;

		if (rc == -ENODEV) {
			ehc->i.probe_mask |= 1;
			detach = 1;
			/* give it just two more chances */
			tries = min(tries, 2);
		}

		if (tries) {
			int sleep = ehc->i.flags & ATA_EHI_DID_RESET;

			/* consecutive revalidation failures? speed down */
			if (reval_failed)
				sata_down_spd_limit(link);
			else
				reval_failed = 1;

			ata_dev_printk(dev, KERN_WARNING,
				       "retrying hardreset%s\n",
				       sleep ? " in 5 secs" : "");
			if (sleep)
				ssleep(5);
			ehc->i.action |= ATA_EH_HARDRESET;
			goto retry;
		} else {
			ata_dev_printk(dev, KERN_ERR, "failed to recover PMP "
				       "after %d tries, giving up\n",
				       ATA_EH_PMP_TRIES);
			goto fail;
		}
	}

	/* okay, PMP resurrected */
	ehc->i.flags = 0;

	DPRINTK("EXIT, rc=0\n");
	return 0;

 fail:
	sata_pmp_detach(dev);
	if (detach)
		ata_eh_detach_dev(dev);
	else
		ata_dev_disable(dev);

	DPRINTK("EXIT, rc=%d\n", rc);
	return rc;
}

static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
{
	struct ata_link *link;
	unsigned long flags;
	int rc;

	spin_lock_irqsave(ap->lock, flags);

	ata_port_for_each_link(link, ap) {
		if (!(link->flags & ATA_LFLAG_DISABLED))
			continue;

		spin_unlock_irqrestore(ap->lock, flags);

		/* Some PMPs require hardreset sequence to get
		 * SError.N working.
		 */
		if ((link->flags & ATA_LFLAG_HRST_TO_RESUME) &&
		    (link->eh_context.i.flags & ATA_EHI_RESUME_LINK))
			sata_link_hardreset(link, sata_deb_timing_normal,
					    jiffies + ATA_TMOUT_INTERNAL_QUICK);

		/* unconditionally clear SError.N */
		rc = sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
		if (rc) {
			ata_link_printk(link, KERN_ERR, "failed to clear "
					"SError.N (errno=%d)\n", rc);
			return rc;
		}

		spin_lock_irqsave(ap->lock, flags);
	}

	spin_unlock_irqrestore(ap->lock, flags);

	return 0;
}

static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
{
	struct ata_port *ap = link->ap;
	unsigned long flags;

	if (link_tries[link->pmp] && --link_tries[link->pmp])
		return 1;

	/* disable this link */
	if (!(link->flags & ATA_LFLAG_DISABLED)) {
		ata_link_printk(link, KERN_WARNING,
			"failed to recover link after %d tries, disabling\n",
			ATA_EH_PMP_LINK_TRIES);

		spin_lock_irqsave(ap->lock, flags);
		link->flags |= ATA_LFLAG_DISABLED;
		spin_unlock_irqrestore(ap->lock, flags);
	}

	ata_dev_disable(link->device);
	link->eh_context.i.action = 0;

	return 0;
}

/**
 *	sata_pmp_eh_recover - recover PMP-enabled port
 *	@ap: ATA port to recover
 *	@prereset: prereset method (can be NULL)
 *	@softreset: softreset method
 *	@hardreset: hardreset method
 *	@postreset: postreset method (can be NULL)
 *	@pmp_prereset: PMP prereset method (can be NULL)
 *	@pmp_softreset: PMP softreset method (can be NULL)
 *	@pmp_hardreset: PMP hardreset method (can be NULL)
 *	@pmp_postreset: PMP postreset method (can be NULL)
 *
 *	Drive EH recovery operation for PMP enabled port @ap.  This
 *	function recovers host and PMP ports with proper retrials and
 *	fallbacks.  Actual recovery operations are performed using
 *	ata_eh_recover() and sata_pmp_eh_recover_pmp().
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno on failure.
 */
static int sata_pmp_eh_recover(struct ata_port *ap,
		ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
		ata_reset_fn_t hardreset, ata_postreset_fn_t postreset,
		ata_prereset_fn_t pmp_prereset, ata_reset_fn_t pmp_softreset,
		ata_reset_fn_t pmp_hardreset, ata_postreset_fn_t pmp_postreset)
{
	int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
	struct ata_link *pmp_link = &ap->link;
	struct ata_device *pmp_dev = pmp_link->device;
	struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
	struct ata_link *link;
	struct ata_device *dev;
	unsigned int err_mask;
	u32 gscr_error, sntf;
	int cnt, rc;

	pmp_tries = ATA_EH_PMP_TRIES;
	ata_port_for_each_link(link, ap)
		link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;

 retry:
	/* PMP attached? */
	if (!ap->nr_pmp_links) {
		rc = ata_eh_recover(ap, prereset, softreset, hardreset,
				    postreset, NULL);
		if (rc) {
			ata_link_for_each_dev(dev, &ap->link)
				ata_dev_disable(dev);
			return rc;
		}

		if (pmp_dev->class != ATA_DEV_PMP)
			return 0;

		/* new PMP online */
		ata_port_for_each_link(link, ap)
			link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;

		/* fall through */
	}

	/* recover pmp */
	rc = sata_pmp_eh_recover_pmp(ap, prereset, softreset, hardreset,
				     postreset);
	if (rc)
		goto pmp_fail;

	/* handle disabled links */
	rc = sata_pmp_eh_handle_disabled_links(ap);
	if (rc)
		goto pmp_fail;

	/* recover links */
	rc = ata_eh_recover(ap, pmp_prereset, pmp_softreset, pmp_hardreset,
			    pmp_postreset, &link);
	if (rc)
		goto link_fail;

	/* Connection status might have changed while resetting other
	 * links, check SATA_PMP_GSCR_ERROR before returning.
	 */

	/* clear SNotification */
	rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
	if (rc == 0)
		sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);

	/* enable notification */
	if (pmp_dev->flags & ATA_DFLAG_AN) {
		pmp_dev->gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;

		err_mask = sata_pmp_write(pmp_dev->link, SATA_PMP_GSCR_FEAT_EN,
					  pmp_dev->gscr[SATA_PMP_GSCR_FEAT_EN]);
		if (err_mask) {
			ata_dev_printk(pmp_dev, KERN_ERR, "failed to write "
				       "PMP_FEAT_EN (Emask=0x%x)\n", err_mask);
			rc = -EIO;
			goto pmp_fail;
		}
	}

	/* check GSCR_ERROR */
	err_mask = sata_pmp_read(pmp_link, SATA_PMP_GSCR_ERROR, &gscr_error);
	if (err_mask) {
		ata_dev_printk(pmp_dev, KERN_ERR, "failed to read "
			       "PMP_GSCR_ERROR (Emask=0x%x)\n", err_mask);
		rc = -EIO;
		goto pmp_fail;
	}

	cnt = 0;
	ata_port_for_each_link(link, ap) {
		if (!(gscr_error & (1 << link->pmp)))
			continue;

		if (sata_pmp_handle_link_fail(link, link_tries)) {
			ata_ehi_hotplugged(&link->eh_context.i);
			cnt++;
		} else {
			ata_link_printk(link, KERN_WARNING,
				"PHY status changed but maxed out on retries, "
				"giving up\n");
			ata_link_printk(link, KERN_WARNING,
				"Manully issue scan to resume this link\n");
		}
	}

	if (cnt) {
		ata_port_printk(ap, KERN_INFO, "PMP SError.N set for some "
				"ports, repeating recovery\n");
		goto retry;
	}

	return 0;

 link_fail:
	if (sata_pmp_handle_link_fail(link, link_tries)) {
		pmp_ehc->i.action |= ATA_EH_HARDRESET;
		goto retry;
	}

	/* fall through */
 pmp_fail:
	/* Control always ends up here after detaching PMP.  Shut up
	 * and return if we're unloading.
	 */
	if (ap->pflags & ATA_PFLAG_UNLOADING)
		return rc;

	if (!ap->nr_pmp_links)
		goto retry;

	if (--pmp_tries) {
		ata_port_printk(ap, KERN_WARNING,
				"failed to recover PMP, retrying in 5 secs\n");
		pmp_ehc->i.action |= ATA_EH_HARDRESET;
		ssleep(5);
		goto retry;
	}

	ata_port_printk(ap, KERN_ERR,
			"failed to recover PMP after %d tries, giving up\n",
			ATA_EH_PMP_TRIES);
	sata_pmp_detach(pmp_dev);
	ata_dev_disable(pmp_dev);

	return rc;
}

/**
 *	sata_pmp_do_eh - do standard error handling for PMP-enabled host
 *	@ap: host port to handle error for
 *	@prereset: prereset method (can be NULL)
 *	@softreset: softreset method
 *	@hardreset: hardreset method
 *	@postreset: postreset method (can be NULL)
 *	@pmp_prereset: PMP prereset method (can be NULL)
 *	@pmp_softreset: PMP softreset method (can be NULL)
 *	@pmp_hardreset: PMP hardreset method (can be NULL)
 *	@pmp_postreset: PMP postreset method (can be NULL)
 *
 *	Perform standard error handling sequence for PMP-enabled host
 *	@ap.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep).
 */
void sata_pmp_do_eh(struct ata_port *ap,
		ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
		ata_reset_fn_t hardreset, ata_postreset_fn_t postreset,
		ata_prereset_fn_t pmp_prereset, ata_reset_fn_t pmp_softreset,
		ata_reset_fn_t pmp_hardreset, ata_postreset_fn_t pmp_postreset)
{
	ata_eh_autopsy(ap);
	ata_eh_report(ap);
	sata_pmp_eh_recover(ap, prereset, softreset, hardreset, postreset,
			    pmp_prereset, pmp_softreset, pmp_hardreset,
			    pmp_postreset);
	ata_eh_finish(ap);
}