scsi: hisi_sas: fix reset and port ID refresh issues

This patch provides fixes for the following issues:

1. Fix issue of controller reset required to send commands. For reset
   process, it may be required to send commands to the controller, but
   not during soft reset.  So add HISI_SAS_NOT_ACCEPT_CMD_BIT to prevent
   executing a task during this period.

2. Send a broadcast event in rescan topology to detect any topology
   changes during reset.

3. Previously it was not ensured that libsas has processed the PHY up
   and down events after reset. Potentially this could cause an issue
   that we still process the PHY event after reset. So resolve this by
   flushing shot workqueue in LLDD reset.

4. Port ID requires refresh after reset. The port ID generated after
   reset is not guaranteed to be the same as before reset, so it needs
   to be refreshed for each device's ITCT.
Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hisi_sas/hisi_sas.h

@@ -33,6 +33,7 @@
 #define HISI_SAS_MAX_ITCT_ENTRIES 2048
 #define HISI_SAS_MAX_DEVICES HISI_SAS_MAX_ITCT_ENTRIES
 #define HISI_SAS_RESET_BIT	0
+#define HISI_SAS_REJECT_CMD_BIT	1
 
 #define HISI_SAS_STATUS_BUF_SZ (sizeof(struct hisi_sas_status_buffer))
 #define HISI_SAS_COMMAND_TABLE_SZ (sizeof(union hisi_sas_command_table))
@@ -201,6 +202,7 @@ struct hisi_sas_hw {
 	void (*dereg_device)(struct hisi_hba *hisi_hba,
 				struct domain_device *device);
 	int (*soft_reset)(struct hisi_hba *hisi_hba);
+	u32 (*get_phys_state)(struct hisi_hba *hisi_hba);
 	int max_command_entries;
 	int complete_hdr_size;
 };
@@ -408,6 +410,4 @@ extern void hisi_sas_slot_task_free(struct hisi_hba *hisi_hba,
 				    struct sas_task *task,
 				    struct hisi_sas_slot *slot);
 extern void hisi_sas_init_mem(struct hisi_hba *hisi_hba);
-extern void hisi_sas_rescan_topology(struct hisi_hba *hisi_hba, u32 old_state,
-				     u32 state);
 #endif

drivers/scsi/hisi_sas/hisi_sas_main.c

@@ -433,7 +433,7 @@ static int hisi_sas_task_exec(struct sas_task *task, gfp_t gfp_flags,
 	struct hisi_sas_device *sas_dev = device->lldd_dev;
 	struct hisi_sas_dq *dq = sas_dev->dq;
 
-	if (unlikely(test_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags)))
+	if (unlikely(test_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags)))
 		return -EINVAL;
 
 	/* protect task_prep and start_delivery sequence */
@@ -967,23 +967,94 @@ static int hisi_sas_debug_issue_ssp_tmf(struct domain_device *device,
 				sizeof(ssp_task), tmf);
 }
 
+static void hisi_sas_refresh_port_id(struct hisi_hba *hisi_hba,
+		struct asd_sas_port *sas_port, enum sas_linkrate linkrate)
+{
+	struct hisi_sas_device	*sas_dev;
+	struct domain_device *device;
+	int i;
+
+	for (i = 0; i < HISI_SAS_MAX_DEVICES; i++) {
+		sas_dev = &hisi_hba->devices[i];
+		device = sas_dev->sas_device;
+		if ((sas_dev->dev_type == SAS_PHY_UNUSED)
+				|| !device || (device->port != sas_port))
+			continue;
+
+		hisi_hba->hw->free_device(hisi_hba, sas_dev);
+
+		/* Update linkrate of directly attached device. */
+		if (!device->parent)
+			device->linkrate = linkrate;
+
+		hisi_hba->hw->setup_itct(hisi_hba, sas_dev);
+	}
+}
+
+static void hisi_sas_rescan_topology(struct hisi_hba *hisi_hba, u32 old_state,
+			      u32 state)
+{
+	struct sas_ha_struct *sas_ha = &hisi_hba->sha;
+	struct asd_sas_port *_sas_port = NULL;
+	int phy_no;
+
+	for (phy_no = 0; phy_no < hisi_hba->n_phy; phy_no++) {
+		struct hisi_sas_phy *phy = &hisi_hba->phy[phy_no];
+		struct asd_sas_phy *sas_phy = &phy->sas_phy;
+		struct asd_sas_port *sas_port = sas_phy->port;
+		struct hisi_sas_port *port = to_hisi_sas_port(sas_port);
+		bool do_port_check = !!(_sas_port != sas_port);
+
+		if (!sas_phy->phy->enabled)
+			continue;
+
+		/* Report PHY state change to libsas */
+		if (state & (1 << phy_no)) {
+			if (do_port_check && sas_port) {
+				struct domain_device *dev = sas_port->port_dev;
+
+				_sas_port = sas_port;
+				port->id = phy->port_id;
+				hisi_sas_refresh_port_id(hisi_hba,
+						sas_port, sas_phy->linkrate);
+
+				if (DEV_IS_EXPANDER(dev->dev_type))
+					sas_ha->notify_port_event(sas_phy,
+							PORTE_BROADCAST_RCVD);
+			}
+		} else if (old_state & (1 << phy_no))
+			/* PHY down but was up before */
+			hisi_sas_phy_down(hisi_hba, phy_no, 0);
+
+	}
+
+	drain_workqueue(hisi_hba->shost->work_q);
+}
+
 static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
 {
+	struct sas_ha_struct *sas_ha = &hisi_hba->sha;
+	struct device *dev = hisi_hba->dev;
+	struct Scsi_Host *shost = hisi_hba->shost;
+	u32 old_state, state;
+	unsigned long flags;
 	int rc;
 
 	if (!hisi_hba->hw->soft_reset)
 		return -1;
 
-	if (!test_and_set_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags)) {
-		struct device *dev = hisi_hba->dev;
-		struct sas_ha_struct *sas_ha = &hisi_hba->sha;
-		unsigned long flags;
+	if (test_and_set_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags))
+		return -1;
 
-		dev_dbg(dev, "controller reset begins!\n");
-		scsi_block_requests(hisi_hba->shost);
+	dev_dbg(dev, "controller resetting...\n");
+	old_state = hisi_hba->hw->get_phys_state(hisi_hba);
+
+	scsi_block_requests(shost);
+	set_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
 	rc = hisi_hba->hw->soft_reset(hisi_hba);
 	if (rc) {
 		dev_warn(dev, "controller reset failed (%d)\n", rc);
+		clear_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
 		goto out;
 	}
 	spin_lock_irqsave(&hisi_hba->lock, flags);
@@ -991,13 +1062,22 @@ static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
 	spin_unlock_irqrestore(&hisi_hba->lock, flags);
 
 	sas_ha->notify_ha_event(sas_ha, HAE_RESET);
-		dev_dbg(dev, "controller reset successful!\n");
-	} else
-		return -1;
+	clear_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
+
+	/* Init and wait for PHYs to come up and all libsas event finished. */
+	hisi_hba->hw->phys_init(hisi_hba);
+	msleep(1000);
+	drain_workqueue(hisi_hba->wq);
+	drain_workqueue(shost->work_q);
+
+	state = hisi_hba->hw->get_phys_state(hisi_hba);
+	hisi_sas_rescan_topology(hisi_hba, old_state, state);
+	dev_dbg(dev, "controller reset complete\n");
 
 out:
-	scsi_unblock_requests(hisi_hba->shost);
+	scsi_unblock_requests(shost);
 	clear_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags);
+
 	return rc;
 }
 
@@ -1241,7 +1321,7 @@ hisi_sas_internal_abort_task_exec(struct hisi_hba *hisi_hba, int device_id,
 	int dlvry_queue_slot, dlvry_queue, n_elem = 0, rc, slot_idx;
 	unsigned long flags, flags_dq;
 
-	if (unlikely(test_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags)))
+	if (unlikely(test_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags)))
 		return -EINVAL;
 
 	if (!device->port)
@@ -1437,36 +1517,6 @@ void hisi_sas_phy_down(struct hisi_hba *hisi_hba, int phy_no, int rdy)
 }
 EXPORT_SYMBOL_GPL(hisi_sas_phy_down);
 
-void hisi_sas_rescan_topology(struct hisi_hba *hisi_hba, u32 old_state,
-			      u32 state)
-{
-	struct sas_ha_struct *sas_ha = &hisi_hba->sha;
-	int phy_no;
-
-	for (phy_no = 0; phy_no < hisi_hba->n_phy; phy_no++) {
-		struct hisi_sas_phy *phy = &hisi_hba->phy[phy_no];
-		struct asd_sas_phy *sas_phy = &phy->sas_phy;
-		struct asd_sas_port *sas_port = sas_phy->port;
-		struct domain_device *dev;
-
-		if (sas_phy->enabled) {
-			/* Report PHY state change to libsas */
-			if (state & (1 << phy_no))
-				continue;
-
-			if (old_state & (1 << phy_no))
-				/* PHY down but was up before */
-				hisi_sas_phy_down(hisi_hba, phy_no, 0);
-		}
-		if (!sas_port)
-			continue;
-		dev = sas_port->port_dev;
-
-		if (DEV_IS_EXPANDER(dev->dev_type))
-			sas_ha->notify_phy_event(sas_phy, PORTE_BROADCAST_RCVD);
-	}
-}
-EXPORT_SYMBOL_GPL(hisi_sas_rescan_topology);
 
 struct scsi_transport_template *hisi_sas_stt;
 EXPORT_SYMBOL_GPL(hisi_sas_stt);

drivers/scsi/hisi_sas/hisi_sas_v2_hw.c

@@ -1364,8 +1364,15 @@ static void start_phys_v2_hw(struct hisi_hba *hisi_hba)
 {
 	int i;
 
-	for (i = 0; i < hisi_hba->n_phy; i++)
+	for (i = 0; i < hisi_hba->n_phy; i++) {
+		struct hisi_sas_phy *phy = &hisi_hba->phy[i];
+		struct asd_sas_phy *sas_phy = &phy->sas_phy;
+
+		if (!sas_phy->phy->enabled)
+			continue;
+
 		start_phy_v2_hw(hisi_hba, i);
+	}
 }
 
 static void phys_init_v2_hw(struct hisi_hba *hisi_hba)
@@ -3383,14 +3390,16 @@ static void interrupt_disable_v2_hw(struct hisi_hba *hisi_hba)
 		synchronize_irq(platform_get_irq(pdev, i));
 }
 
+
+static u32 get_phys_state_v2_hw(struct hisi_hba *hisi_hba)
+{
+	return hisi_sas_read32(hisi_hba, PHY_STATE);
+}
+
 static int soft_reset_v2_hw(struct hisi_hba *hisi_hba)
 {
 	struct device *dev = hisi_hba->dev;
-	u32 old_state, state;
 	int rc, cnt;
-	int phy_no;
-
-	old_state = hisi_sas_read32(hisi_hba, PHY_STATE);
 
 	interrupt_disable_v2_hw(hisi_hba);
 	hisi_sas_write32(hisi_hba, DLVRY_QUEUE_ENABLE, 0x0);
@@ -3425,22 +3434,6 @@ static int soft_reset_v2_hw(struct hisi_hba *hisi_hba)
 
 	phys_reject_stp_links_v2_hw(hisi_hba);
 
-	/* Re-enable the PHYs */
-	for (phy_no = 0; phy_no < hisi_hba->n_phy; phy_no++) {
-		struct hisi_sas_phy *phy = &hisi_hba->phy[phy_no];
-		struct asd_sas_phy *sas_phy = &phy->sas_phy;
-
-		if (sas_phy->enabled)
-			start_phy_v2_hw(hisi_hba, phy_no);
-	}
-
-	/* Wait for the PHYs to come up and read the PHY state */
-	msleep(1000);
-
-	state = hisi_sas_read32(hisi_hba, PHY_STATE);
-
-	hisi_sas_rescan_topology(hisi_hba, old_state, state);
-
 	return 0;
 }
 
@@ -3468,6 +3461,7 @@ static const struct hisi_sas_hw hisi_sas_v2_hw = {
 	.max_command_entries = HISI_SAS_COMMAND_ENTRIES_V2_HW,
 	.complete_hdr_size = sizeof(struct hisi_sas_complete_v2_hdr),
 	.soft_reset = soft_reset_v2_hw,
+	.get_phys_state = get_phys_state_v2_hw,
 };
 
 static int hisi_sas_v2_probe(struct platform_device *pdev)