From: Xiang Chen <chenxiang66@hisilicon.com>
Date: Mon, 20 Dec 2021 19:21:36 +0800
Subject: scsi: hisi_sas: Keep controller active between ISR of phyup and the
 event being processed
Git-commit: ae9b69e85eb7ecb32ddce7c04a10a3c69ad60e52
Patch-mainline: v5.17-rc1
References: bsc#1202471

It is possible that controller may become suspended between processing a
phyup interrupt and the event being processed by libsas. As such, we can't
ensure the controller is active when processing the phyup event - this may
cause the phyup event to be lost or other issues.  To avoid any possible
issues, add pm_runtime_get_noresume() in phyup interrupt handler and
pm_runtime_put_sync() in the work handler exit to ensure that we stay
always active. Since we only want to call pm_runtime_get_noresume() for v3
hw, signal this will a new event, HISI_PHYE_PHY_UP_PM.

[lduncan: refreshed to apply to hisi_sas_v3_hw.c]

Link: https://lore.kernel.org/r/1639999298-244569-14-git-send-email-chenxiang66@hisilicon.com
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Lee Duncan <lduncan@suse.com>
---
 drivers/scsi/hisi_sas/hisi_sas.h       |    1 +
 drivers/scsi/hisi_sas/hisi_sas_main.c  |   22 ++++++++++++++++++++--
 drivers/scsi/hisi_sas/hisi_sas_v3_hw.c |    6 +++++-
 3 files changed, 26 insertions(+), 3 deletions(-)

--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -154,6 +154,7 @@ enum hisi_sas_bit_err_type {
 enum hisi_sas_phy_event {
 	HISI_PHYE_PHY_UP   = 0U,
 	HISI_PHYE_LINK_RESET,
+	HISI_PHYE_PHY_UP_PM,
 	HISI_PHYES_NUM,
 };
 
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -854,10 +854,11 @@ int hisi_sas_scan_finished(struct Scsi_H
 }
 EXPORT_SYMBOL_GPL(hisi_sas_scan_finished);
 
-static void hisi_sas_phyup_work(struct work_struct *work)
+static void hisi_sas_phyup_work_common(struct work_struct *work,
+		enum hisi_sas_phy_event event)
 {
 	struct hisi_sas_phy *phy =
-		container_of(work, typeof(*phy), works[HISI_PHYE_PHY_UP]);
+		container_of(work, typeof(*phy), works[event]);
 	struct hisi_hba *hisi_hba = phy->hisi_hba;
 	struct asd_sas_phy *sas_phy = &phy->sas_phy;
 	int phy_no = sas_phy->id;
@@ -868,6 +869,11 @@ static void hisi_sas_phyup_work(struct w
 	hisi_sas_bytes_dmaed(hisi_hba, phy_no, GFP_KERNEL);
 }
 
+static void hisi_sas_phyup_work(struct work_struct *work)
+{
+	hisi_sas_phyup_work_common(work, HISI_PHYE_PHY_UP);
+}
+
 static void hisi_sas_linkreset_work(struct work_struct *work)
 {
 	struct hisi_sas_phy *phy =
@@ -877,9 +883,21 @@ static void hisi_sas_linkreset_work(stru
 	hisi_sas_control_phy(sas_phy, PHY_FUNC_LINK_RESET, NULL);
 }
 
+static void hisi_sas_phyup_pm_work(struct work_struct *work)
+{
+	struct hisi_sas_phy *phy =
+		container_of(work, typeof(*phy), works[HISI_PHYE_PHY_UP_PM]);
+	struct hisi_hba *hisi_hba = phy->hisi_hba;
+	struct device *dev = hisi_hba->dev;
+
+	hisi_sas_phyup_work_common(work, HISI_PHYE_PHY_UP_PM);
+	pm_runtime_put_sync(dev);
+}
+
 static const work_func_t hisi_sas_phye_fns[HISI_PHYES_NUM] = {
 	[HISI_PHYE_PHY_UP] = hisi_sas_phyup_work,
 	[HISI_PHYE_LINK_RESET] = hisi_sas_linkreset_work,
+	[HISI_PHYE_PHY_UP_PM] = hisi_sas_phyup_pm_work,
 };
 
 bool hisi_sas_notify_phy_event(struct hisi_sas_phy *phy,
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -1559,7 +1559,11 @@ static irqreturn_t phy_up_v3_hw(int phy_
 
 	phy->port_id = port_id;
 	phy->phy_attached = 1;
-	hisi_sas_notify_phy_event(phy, HISI_PHYE_PHY_UP);
+
+	/* Call pm_runtime_put_sync() with pairs in hisi_sas_phyup_pm_work() */
+	pm_runtime_get_noresume(dev);
+	hisi_sas_notify_phy_event(phy, HISI_PHYE_PHY_UP_PM);
+
 	res = IRQ_HANDLED;
 end:
 	if (phy->reset_completion)