scsi: hpsa: add controller checkpoint

Tell hpsa controller to generate a checkpoint for rare lockup
conditions.
Reviewed-by: NScott Benesh <scott.benesh@microsemi.com>
Reviewed-by: NScott Teel <scott.teel@microsemi.com>
Reviewed-by: NKevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: NDon Brace <don.brace@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hpsa.c

@@ -8009,6 +8009,10 @@ static void controller_lockup_detected(struct ctlr_info *h)
 	spin_unlock_irqrestore(&h->lock, flags);
 	dev_warn(&h->pdev->dev, "Controller lockup detected: 0x%08x after %d\n",
 			lockup_detected, h->heartbeat_sample_interval / HZ);
+	if (lockup_detected == 0xffff0000) {
+		dev_warn(&h->pdev->dev, "Telling controller to do a CHKPT\n");
+		writel(DOORBELL_GENERATE_CHKPT, h->vaddr + SA5_DOORBELL);
+	}
 	pci_disable_device(h->pdev);
 	fail_all_outstanding_cmds(h);
 }

drivers/scsi/hpsa_cmd.h

@@ -142,6 +142,7 @@
 #define DOORBELL_CTLR_RESET	0x00000004l
 #define DOORBELL_CTLR_RESET2	0x00000020l
 #define DOORBELL_CLEAR_EVENTS	0x00000040l
+#define DOORBELL_GENERATE_CHKPT	0x00000080l
 
 #define CFGTBL_Trans_Simple     0x00000002l
 #define CFGTBL_Trans_Performant 0x00000004l