scsi: hisi_sas: Do not reset phy timer to wait for stray phy up

We found out that after phy up, the hardware reports another oob interrupt
but did not follow a phy up interrupt:

oob ready -> phy up -> DEV found -> oob read -> wait phy up -> timeout

We run link reset when wait phy up timeout, and it send a normal disk into
reset processing. So we made some circumvention action in the code, so that
this abnormal oob interrupt will not start the timer to wait for phy up.

Link: https://lore.kernel.org/r/1589552025-165012-2-git-send-email-john.garry@huawei.comSigned-off-by: Luo Jiaxing <luojiaxing@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_main.c

@@ -898,8 +898,11 @@ void hisi_sas_phy_oob_ready(struct hisi_hba *hisi_hba, int phy_no)
 	struct hisi_sas_phy *phy = &hisi_hba->phy[phy_no];
 	struct device *dev = hisi_hba->dev;
 
-	if (!timer_pending(&phy->timer)) {
 	dev_dbg(dev, "phy%d OOB ready\n", phy_no);
+	if (phy->phy_attached)
+		return;
+
+	if (!timer_pending(&phy->timer)) {
 		phy->timer.expires = jiffies + HISI_SAS_WAIT_PHYUP_TIMEOUT * HZ;
 		add_timer(&phy->timer);
 	}