diff mbox series

[V2,3/3] pm80xx : Wait for PHY startup before draining libsas queue.

Message ID 20200624120322.6265-4-deepak.ukey@microchip.com
State New
Headers show
Series [V2,1/3] pm80xx : Support for get phy profile functionality. | expand

Commit Message

Deepak Ukey June 24, 2020, 12:03 p.m. UTC
From: peter chang <dpf@google.com>

The host's scan finish waits for the libsas queue to drain. However,
if the PHYs are still in the process of starting then the queue will
be empty. This means that we declare the scan finished before it has
even started. Here we wait for various events from the firmware-side.

The wait behavior can be configured using the module parameter
"wait_for_phy_startup", if the parameter is enabled, the driver will wait
for the phy event from the firmware, before proceeding with load.

Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: peter chang <dpf@google.com>
Signed-off-by: Radha Ramachandran <radha@google.com>
Signed-off-by: Deepak Ukey <Deepak.Ukey@microchip.com>
---
 drivers/scsi/pm8001/pm8001_ctl.c  | 36 +++++++++++++++++++++
 drivers/scsi/pm8001/pm8001_defs.h |  6 ++--
 drivers/scsi/pm8001/pm8001_init.c | 22 +++++++++++++
 drivers/scsi/pm8001/pm8001_sas.c  | 67 +++++++++++++++++++++++++++++++++++++--
 drivers/scsi/pm8001/pm8001_sas.h  |  4 +++
 drivers/scsi/pm8001/pm80xx_hwi.c  | 67 ++++++++++++++++++++++++++++++++-------
 6 files changed, 185 insertions(+), 17 deletions(-)

Comments

Deepak Ukey July 14, 2020, 4:49 a.m. UTC | #1
EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe

On 24/06/2020 13:03, Deepak Ukey wrote:


> From: peter chang <dpf@google.com>

>

> The host's scan finish waits for the libsas queue to drain. However, 

> if the PHYs are still in the process of starting then the queue will 

> be empty. This means that we declare the scan finished before it has 

> even started. Here we wait for various events from the firmware-side.


But we still report the phy up even to libsas later, so should revalidate the domain and discover the device.
- The scsi_host scan_finished callback polls the phy state in pm8001_update_phy_mask. If the phy fails to come up - - after phy->start_timeout, we declare the scan as finished and proceed.
>

> The wait behavior can be configured using the module parameter 

> "wait_for_phy_startup", if the parameter is enabled, the driver will 

> wait for the phy event from the firmware, before proceeding with load.


If this is to circumvent a deficiency in udev (which you mentioned in the v1 in this series, but fail to mention here), then better to fix udev.
- According to recommendation to fix this using udev. It looks like upstreaming this patch is not possible. We will       - investigate using udev for fixing this issue and submit this patch later in  future.

>

> Signed-off-by: Viswas G <Viswas.G@microchip.com>


Author != first Signed-off-by

> Signed-off-by: peter chang <dpf@google.com>

> Signed-off-by: Radha Ramachandran <radha@google.com>

> Signed-off-by: Deepak Ukey <Deepak.Ukey@microchip.com>

> ---

>   drivers/scsi/pm8001/pm8001_ctl.c  | 36 +++++++++++++++++++++

>   drivers/scsi/pm8001/pm8001_defs.h |  6 ++--

>   drivers/scsi/pm8001/pm8001_init.c | 22 +++++++++++++

>   drivers/scsi/pm8001/pm8001_sas.c  | 67 +++++++++++++++++++++++++++++++++++++--

>   drivers/scsi/pm8001/pm8001_sas.h  |  4 +++

>   drivers/scsi/pm8001/pm80xx_hwi.c  | 67 ++++++++++++++++++++++++++++++++-------

>   6 files changed, 185 insertions(+), 17 deletions(-)

>

> diff --git a/drivers/scsi/pm8001/pm8001_ctl.c 

> b/drivers/scsi/pm8001/pm8001_ctl.c

> index 3c9f42779dd0..eae629610a5f 100644

> --- a/drivers/scsi/pm8001/pm8001_ctl.c

> +++ b/drivers/scsi/pm8001/pm8001_ctl.c

> @@ -88,6 +88,41 @@ static ssize_t controller_fatal_error_show(struct device *cdev,

>   }

>   static DEVICE_ATTR_RO(controller_fatal_error);

>

> +/**

> + * phy_startup_timeout_show - per-phy discovery timeout

> + * @cdev: pointer to embedded class device

> + * @buf: the buffer returned

> + *

> + * A sysfs 'read/write' shost attribute.

> + */

> +static ssize_t phy_startup_timeout_show(struct device *cdev,

> +     struct device_attribute *attr, char *buf) {

> +     struct Scsi_Host *shost = class_to_shost(cdev);

> +     struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);

> +     struct pm8001_hba_info *pm8001_ha = sha->lldd_ha;

> +

> +     return snprintf(buf, PAGE_SIZE, "%08xh\n",

> +             pm8001_ha->phy_startup_timeout / HZ); }

> +

> +static ssize_t phy_startup_timeout_store(struct device *cdev,

> +     struct device_attribute *attr, const char *buf, size_t count) {

> +     struct Scsi_Host *shost = class_to_shost(cdev);

> +     struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);

> +     struct pm8001_hba_info *pm8001_ha = sha->lldd_ha;

> +     int val = 0;

> +

> +     if (kstrtoint(buf, 0, &val) < 0)

> +             return -EINVAL;

> +

> +     pm8001_ha->phy_startup_timeout = val * HZ;

> +     return strlen(buf);


I don't see how this can be used.

> +}

> +

> +static DEVICE_ATTR_RW(phy_startup_timeout);

> +


 >

 >      case HW_EVENT_SAS_PHY_UP:

 > @@ -4975,6 +5015,9 @@ pm80xx_chip_phy_start_req(struct pm8001_hba_info *pm8001_ha, u8 phy_id)  >

 >      PM8001_INIT_DBG(pm8001_ha,

 >              pm8001_printk("PHY START REQ for phy_id %d\n", phy_id));

 > +    set_bit(phy_id, &pm8001_ha->phy_mask);

 > +    pm8001_ha->phy[phy_id].start_timeout =

 > +            jiffies + pm8001_ha->phy_startup_timeout;

 >

 >      payload.ase_sh_lm_slr_phyid = cpu_to_le32(SPINHOLD_ENABLE |

 >                      LINKMODE_AUTO | pm8001_ha->link_rate | phy_id);

 > --


If there is nothing attached to the phy, then it would never come up, right? If so, how do you handle this?

Thanks,
john
diff mbox series

Patch

diff --git a/drivers/scsi/pm8001/pm8001_ctl.c b/drivers/scsi/pm8001/pm8001_ctl.c
index 3c9f42779dd0..eae629610a5f 100644
--- a/drivers/scsi/pm8001/pm8001_ctl.c
+++ b/drivers/scsi/pm8001/pm8001_ctl.c
@@ -88,6 +88,41 @@  static ssize_t controller_fatal_error_show(struct device *cdev,
 }
 static DEVICE_ATTR_RO(controller_fatal_error);
 
+/**
+ * phy_startup_timeout_show - per-phy discovery timeout
+ * @cdev: pointer to embedded class device
+ * @buf: the buffer returned
+ *
+ * A sysfs 'read/write' shost attribute.
+ */
+static ssize_t phy_startup_timeout_show(struct device *cdev,
+	struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(cdev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+	struct pm8001_hba_info *pm8001_ha = sha->lldd_ha;
+
+	return snprintf(buf, PAGE_SIZE, "%08xh\n",
+		pm8001_ha->phy_startup_timeout / HZ);
+}
+
+static ssize_t phy_startup_timeout_store(struct device *cdev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(cdev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+	struct pm8001_hba_info *pm8001_ha = sha->lldd_ha;
+	int val = 0;
+
+	if (kstrtoint(buf, 0, &val) < 0)
+		return -EINVAL;
+
+	pm8001_ha->phy_startup_timeout = val * HZ;
+	return strlen(buf);
+}
+
+static DEVICE_ATTR_RW(phy_startup_timeout);
+
 /**
  * pm8001_ctl_fw_version_show - firmware version
  * @cdev: pointer to embedded class device
@@ -867,6 +902,7 @@  static DEVICE_ATTR(update_fw, S_IRUGO|S_IWUSR|S_IWGRP,
 struct device_attribute *pm8001_host_attrs[] = {
 	&dev_attr_interface_rev,
 	&dev_attr_controller_fatal_error,
+	&dev_attr_phy_startup_timeout,
 	&dev_attr_fw_version,
 	&dev_attr_update_fw,
 	&dev_attr_aap_log,
diff --git a/drivers/scsi/pm8001/pm8001_defs.h b/drivers/scsi/pm8001/pm8001_defs.h
index fd700ce5e80c..aaeabb2f2808 100644
--- a/drivers/scsi/pm8001/pm8001_defs.h
+++ b/drivers/scsi/pm8001/pm8001_defs.h
@@ -141,7 +141,9 @@  enum pm8001_hba_info_flags {
  */
 #define PHY_LINK_DISABLE	0x00
 #define PHY_LINK_DOWN		0x01
-#define PHY_STATE_LINK_UP_SPCV	0x2
-#define PHY_STATE_LINK_UP_SPC	0x1
+#define PHY_STATE_LINK_UP_SPCV	0x02
+#define PHY_STATE_LINK_UP_SPC	0x01
+#define PHY_STATE_LINK_RESET	0x03
+#define PHY_STATE_HARD_RESET	0x04
 
 #endif
diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 46a2f86f3d9b..55b40e4663e6 100644
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -61,6 +61,26 @@  MODULE_PARM_DESC(staggered_spinup, "enable the staggered spinup feature.\n"
 		" 0/N: false\n"
 		" 1/Y: true\n");
 
+static bool wait_for_phy_startup;
+module_param(wait_for_phy_startup, bool, 0644);
+MODULE_PARM_DESC(wait_for_phy_startup, "wait for phy start.\n"
+		" 0/N: disable\n"
+		" 1/Y: enable\n");
+
+/* if nothing is detected, the PHYs will reset continuously once they
+ * are started. we don't have a good way of differentiating a trained
+ * but waiting-on-signature from one that's never going to train
+ * (nothing attached or dead drive), so we wait an possibly
+ * unreasonable amount of time. this is stuck in start_timeout, and
+ * checked in the host's scan_finished callback for PHYs that haven't
+ * yet come up.
+ *
+ */
+static ulong phy_startup_timeout = 60;
+module_param(phy_startup_timeout, ulong, 0644);
+MODULE_PARM_DESC(phy_startup_timeout_s,
+		" seconds to wait for discovery, per-PHY.");
+
 static struct scsi_transport_template *pm8001_stt;
 
 /**
@@ -495,6 +515,8 @@  static struct pm8001_hba_info *pm8001_pci_alloc(struct pci_dev *pdev,
 	pm8001_ha->id = pm8001_id++;
 	pm8001_ha->logging_level = logging_level;
 	pm8001_ha->staggered_spinup = staggered_spinup;
+	pm8001_ha->phy_startup_timeout = phy_startup_timeout * HZ;
+	pm8001_ha->wait_for_phy_startup = wait_for_phy_startup;
 	pm8001_ha->non_fatal_count = 0;
 	if (link_rate >= 1 && link_rate <= 15)
 		pm8001_ha->link_rate = (link_rate << 8);
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index cf1c5e68953b..21086bdae6a9 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -39,6 +39,7 @@ 
  */
 
 #include <linux/slab.h>
+#include "pm80xx_hwi.h"
 #include "pm8001_sas.h"
 
 /**
@@ -257,6 +258,59 @@  int pm8001_phy_control(struct asd_sas_phy *sas_phy, enum phy_func func,
 	return rc;
 }
 
+static int pm8001_update_phy_mask(struct pm8001_hba_info *pm8001_ha)
+{
+	DECLARE_COMPLETION_ONSTACK(comp);
+	unsigned long timeout = msecs_to_jiffies(2000);
+	int ret = 0;
+	int i;
+	struct phy_status *phy_status =
+		kmalloc(sizeof(struct phy_status), GFP_KERNEL);
+	if (phy_status == NULL) {
+		pm8001_printk("Allocation failed\n");
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < pm8001_ha->chip->n_phy; i++) {
+		struct pm8001_phy *phy = pm8001_ha->phy + i;
+
+		if (pm8001_ha->phy_mask & (1 << i) && phy->phy_state) {
+			ret = PM8001_CHIP_DISP->get_phy_profile_req(pm8001_ha,
+					i, SAS_PHY_GENERAL_STATUS_PAGE,
+					&comp, (void *)phy_status);
+			if (ret != 0) {
+				pm8001_printk("get_phy_profile_req:%d:%d\n",
+					i, ret);
+				return ret;
+			}
+			timeout = wait_for_completion_timeout(&comp, timeout);
+			if (timeout == 0)
+				return ret;
+			PM8001_DISC_DBG(pm8001_ha,
+				pm8001_printk("phy_id:%d state:%x nlr:%d plr:%d\n",
+					i,
+					phy_status->phy_state,
+					phy_status->nlr, phy_status->plr));
+			switch (phy_status->phy_state) {
+			case PHY_STATE_LINK_UP_SPCV:
+			case PHY_STATE_LINK_RESET:
+			case PHY_STATE_HARD_RESET:
+				/* these are handled by mpi_hw_event() */
+				break;
+			case PHY_LINK_DOWN:
+				if (time_is_after_jiffies(phy->start_timeout))
+					break;
+				clear_bit(i, &pm8001_ha->phy_mask);
+				break;
+			default:
+				clear_bit(i, &pm8001_ha->phy_mask);
+				break;
+			}
+		}
+	}
+	return ret;
+}
+
 /**
   * pm8001_scan_start - we should enable all HBA phys by sending the phy_start
   * command to HBA.
@@ -274,6 +328,8 @@  void pm8001_scan_start(struct Scsi_Host *shost)
 	if (pm8001_ha->chip_id == chip_8001)
 		PM8001_CHIP_DISP->sas_re_init_req(pm8001_ha);
 
+	pm8001_ha->phy_mask = 0;
+
 	if (pm8001_ha->pdev->device == 0x8001 ||
 		pm8001_ha->pdev->device == 0x8081 ||
 		(pm8001_ha->spinup_interval != 0)) {
@@ -303,11 +359,16 @@  void pm8001_scan_start(struct Scsi_Host *shost)
 int pm8001_scan_finished(struct Scsi_Host *shost, unsigned long time)
 {
 	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct pm8001_hba_info *pm8001_ha = ha->lldd_ha;
 
-	/* give the phy enabling interrupt event time to come in (1s
-	* is empirically about all it takes) */
-	if (time < HZ)
+	/* Wait for PHY startup to finish */
+	PM8001_DISC_DBG(pm8001_ha,
+		pm8001_printk("mask:%lx\n", pm8001_ha->phy_mask));
+	if (pm8001_ha->phy_mask && pm8001_ha->wait_for_phy_startup) {
+		pm8001_update_phy_mask(pm8001_ha);
 		return 0;
+	}
+
 	/* Wait for discovery to finish */
 	sas_drain_work(ha);
 	return 1;
diff --git a/drivers/scsi/pm8001/pm8001_sas.h b/drivers/scsi/pm8001/pm8001_sas.h
index d2d73cba7f41..37c526be55bc 100644
--- a/drivers/scsi/pm8001/pm8001_sas.h
+++ b/drivers/scsi/pm8001/pm8001_sas.h
@@ -283,6 +283,7 @@  struct pm8001_phy {
 	struct completion	*reset_completion;
 	bool			port_reset_status;
 	bool			reset_success;
+	unsigned long		start_timeout;
 };
 
 /* port reset status */
@@ -578,6 +579,9 @@  struct pm8001_hba_info {
 	int			phy_head;
 	int			phy_tail;
 	spinlock_t		phy_q_lock;
+	unsigned long		phy_mask;
+	u32			phy_startup_timeout;
+	bool			wait_for_phy_startup;
 };
 
 struct pm8001_work {
diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index 748c7a06262f..91dc9d6d3657 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -80,18 +80,26 @@  void pm8001_spinup_timedout(struct timer_list *t)
 		if (i++ >= pm8001_ha->spinup_group && pm8001_ha->spinup_group)
 			break;
 
-		if (pm8001_ha->phy_head == -1 || pm8001_ha->reset_in_progress)
-			break; /* No phys to spinup */
-
-		phy_id = pm8001_ha->phy_up[pm8001_ha->phy_head];
-		/* Processed phy id, make it invalid 0xff for
-		 * checking repeated phy ups
-		 */
-		pm8001_ha->phy_up[pm8001_ha->phy_head] = 0xff;
-		if (pm8001_ha->phy_head == pm8001_ha->phy_tail) {
-			pm8001_ha->phy_head = pm8001_ha->phy_tail = -1;
+		if (pm8001_ha->phy_head == -1 ||
+				pm8001_ha->reset_in_progress) {
+			/* No phys to spinup or timeout */
+			if (pm8001_ha->phy_mask) {
+				pm8001_printk("spinup timeout phy_mask:%lx\n",
+					pm8001_ha->phy_mask);
+				pm8001_ha->phy_mask = 0;
+			}
+			break;
 		} else {
-			pm8001_ha->phy_head =
+			phy_id = pm8001_ha->phy_up[pm8001_ha->phy_head];
+			/* Processed phy id, make it invalid 0xff for
+			 * checking repeated phy ups
+			 */
+			pm8001_ha->phy_up[pm8001_ha->phy_head] = 0xff;
+			if (pm8001_ha->phy_head == pm8001_ha->phy_tail)
+				pm8001_ha->phy_head =
+					pm8001_ha->phy_tail = -1;
+			else
+				pm8001_ha->phy_head =
 				(pm8001_ha->phy_head+1) % PM8001_MAX_PHYS;
 		}
 
@@ -3584,8 +3592,10 @@  static int mpi_phy_start_resp(struct pm8001_hba_info *pm8001_ha, void *piomb)
 		phy->enable_completion = NULL;
 	}
 
-	return 0;
+	if (!phy->phy_state)
+		clear_bit(phy_id, &pm8001_ha->phy_mask);
 
+	return 0;
 }
 
 /**
@@ -3646,6 +3656,36 @@  static int mpi_hw_event(struct pm8001_hba_info *pm8001_ha, void *piomb)
 		pm8001_printk("portid:%d phyid:%d event:0x%x status:0x%x\n",
 				port_id, phy_id, eventType, status));
 
+	switch (eventType) {
+		/* the PHY has completed startup and possibly queued
+		 * stuff to the libsas side, so we no longer have to
+		 * track that it is in the middle of doing something
+		 * that libsas doesn't know about.
+		 */
+	case HW_EVENT_SAS_PHY_UP:
+	case HW_EVENT_SATA_PHY_UP:
+	case HW_EVENT_PHY_DOWN:
+	case HW_EVENT_PORT_INVALID:
+	case HW_EVENT_BROADCAST_CHANGE:
+	case HW_EVENT_PHY_ERROR:
+	case HW_EVENT_HARD_RESET_RECEIVED:
+	case HW_EVENT_ID_FRAME_TIMEOUT:
+	case HW_EVENT_LINK_ERR_PHY_RESET_FAILED:
+	case HW_EVENT_PORT_RESET_TIMER_TMO:
+	case HW_EVENT_PORT_RECOVERY_TIMER_TMO:
+	case HW_EVENT_PORT_RECOVER:
+		clear_bit(phy_id, &pm8001_ha->phy_mask);
+		break;
+		/* we may have already gotten the response from the
+		 * PHY, but if the PHY was powered off then this event
+		 * signals that there is more in-flight and we have
+		 * restarted the the spinup timer.
+		 */
+	case HW_EVENT_SATA_SPINUP_HOLD:
+		set_bit(phy_id, &pm8001_ha->phy_mask);
+		break;
+	}
+
 	switch (eventType) {
 
 	case HW_EVENT_SAS_PHY_UP:
@@ -4975,6 +5015,9 @@  pm80xx_chip_phy_start_req(struct pm8001_hba_info *pm8001_ha, u8 phy_id)
 
 	PM8001_INIT_DBG(pm8001_ha,
 		pm8001_printk("PHY START REQ for phy_id %d\n", phy_id));
+	set_bit(phy_id, &pm8001_ha->phy_mask);
+	pm8001_ha->phy[phy_id].start_timeout =
+		jiffies + pm8001_ha->phy_startup_timeout;
 
 	payload.ase_sh_lm_slr_phyid = cpu_to_le32(SPINHOLD_ENABLE |
 			LINKMODE_AUTO | pm8001_ha->link_rate | phy_id);