[PATCH 1/1] pm80xx: fix drive missing during rmmod & insmod in loop.

[PATCH 1/1] pm80xx: fix drive missing during rmmod & insmod in loop.

[ajish.koshy]

From: Ajish Koshy <ajish.koshy@microchip.com>

Most of the time when driver is loaded after rmmod, during drive
discovery few drives are not showing up in lsscsi command. Here
sata drives are directly attached to the controller connected phys.
During device discovery, following identify command (qc timeout
(cmd 0xec)) is getting timedout during revalidation. This will trigger
abort from host side and controller successfully aborts the command
and returns success. Post this successful abort response ATA library
decides to mark the disk as NODEV.

To overcome this, inside pm8001_scan_start() after phy_start() call, added
get start response and wait for few milliseconds to trigger next phy start.
This few millisecond delay will give sufficient time for the controller
state machine to accept next phy start.

Signed-off-by: Ajish Koshy <ajish.koshy@microchip.com>
Signed-off-by: Viswas G <viswas.g@microchip.com>
---
 drivers/scsi/pm8001/pm8001_hwi.c  | 10 ++++++----
 drivers/scsi/pm8001/pm8001_init.c |  2 +-
 drivers/scsi/pm8001/pm8001_sas.c  |  7 ++++++-
 drivers/scsi/pm8001/pm80xx_hwi.c  | 12 ++++++------
 4 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/drivers/scsi/pm8001/pm8001_hwi.c b/drivers/scsi/pm8001/pm8001_hwi.c
index ecd06d2d7e81..71aa6af08340 100644
--- a/drivers/scsi/pm8001/pm8001_hwi.c
+++ b/drivers/scsi/pm8001/pm8001_hwi.c
@@ -3765,11 +3765,13 @@ static int mpi_hw_event(struct pm8001_hba_info *pm8001_ha, void *piomb)
 	case HW_EVENT_PHY_START_STATUS:
 		pm8001_dbg(pm8001_ha, MSG, "HW_EVENT_PHY_START_STATUS status = %x\n",
 			   status);
-		if (status == 0) {
+		if (status == 0)
 			phy->phy_state = 1;
-			if (pm8001_ha->flags == PM8001F_RUN_TIME &&
-					phy->enable_completion != NULL)
-				complete(phy->enable_completion);
+
+		if (pm8001_ha->flags == PM8001F_RUN_TIME &&
+				phy->enable_completion != NULL) {
+			complete(phy->enable_completion);
+			phy->enable_completion = NULL;
 		}
 		break;
 	case HW_EVENT_SAS_PHY_UP:
diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 390c33df0357..af09bd282cb9 100644
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -1151,8 +1151,8 @@ static int pm8001_pci_probe(struct pci_dev *pdev,
 		goto err_out_shost;
 	}
 	list_add_tail(&pm8001_ha->list, &hba_list);
-	scsi_scan_host(pm8001_ha->shost);
 	pm8001_ha->flags = PM8001F_RUN_TIME;
+	scsi_scan_host(pm8001_ha->shost);
 	return 0;
 
 err_out_shost:
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index d28af413b93a..335cf37e6cb9 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -264,12 +264,17 @@ void pm8001_scan_start(struct Scsi_Host *shost)
 	int i;
 	struct pm8001_hba_info *pm8001_ha;
 	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+	DECLARE_COMPLETION_ONSTACK(completion);
 	pm8001_ha = sha->lldd_ha;
 	/* SAS_RE_INITIALIZATION not available in SPCv/ve */
 	if (pm8001_ha->chip_id == chip_8001)
 		PM8001_CHIP_DISP->sas_re_init_req(pm8001_ha);
-	for (i = 0; i < pm8001_ha->chip->n_phy; ++i)
+	for (i = 0; i < pm8001_ha->chip->n_phy; ++i) {
+		pm8001_ha->phy[i].enable_completion = &completion;
 		PM8001_CHIP_DISP->phy_start_req(pm8001_ha, i);
+		wait_for_completion(&completion);
+		msleep(300);
+	}
 }
 
 int pm8001_scan_finished(struct Scsi_Host *shost, unsigned long time)
diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index 4e980830f9f5..700530e969ac 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -3487,13 +3487,13 @@ static int mpi_phy_start_resp(struct pm8001_hba_info *pm8001_ha, void *piomb)
 	pm8001_dbg(pm8001_ha, INIT,
 		   "phy start resp status:0x%x, phyid:0x%x\n",
 		   status, phy_id);
-	if (status == 0) {
+	if (status == 0)
 		phy->phy_state = PHY_LINK_DOWN;
-		if (pm8001_ha->flags == PM8001F_RUN_TIME &&
-				phy->enable_completion != NULL) {
-			complete(phy->enable_completion);
-			phy->enable_completion = NULL;
-		}
+
+	if (pm8001_ha->flags == PM8001F_RUN_TIME &&
+			phy->enable_completion != NULL) {
+		complete(phy->enable_completion);
+		phy->enable_completion = NULL;
 	}
 	return 0;
 
-- 
2.17.1

Re: [PATCH 1/1] pm80xx: fix drive missing during rmmod & insmod in loop.

[Martin K. Petersen]

On Wed, 5 May 2021 17:31:03 +0530, ajish.koshy@microchip.com wrote:

> Most of the time when driver is loaded after rmmod, during drive
> discovery few drives are not showing up in lsscsi command. Here
> sata drives are directly attached to the controller connected phys.
> During device discovery, following identify command (qc timeout
> (cmd 0xec)) is getting timedout during revalidation. This will trigger
> abort from host side and controller successfully aborts the command
> and returns success. Post this successful abort response ATA library
> decides to mark the disk as NODEV.
> 
> [...]

Applied to 5.13/scsi-fixes, thanks!

[1/1] pm80xx: fix drive missing during rmmod & insmod in loop.
      https://git.kernel.org/mkp/scsi/c/d1acd81bd6eb

-- 
Martin K. Petersen	Oracle Linux Engineering