4 files changed, 119 insertions, 16 deletions

diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 670241efa4b5..617664cbf3f7 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -77,6 +77,32 @@ static int msix_disable = -1;
 module_param(msix_disable, int, 0);
 MODULE_PARM_DESC(msix_disable, " disable msix routed interrupts (default=0)");
 
+int mpt2sas_fwfault_debug;
+MODULE_PARM_DESC(mpt2sas_fwfault_debug, " enable detection of firmware fault "
+    "and halt firmware - (default=0)");
+
+/**
+ * _scsih_set_fwfault_debug - global setting of ioc->fwfault_debug.
+ *
+ */
+static int
+_scsih_set_fwfault_debug(const char *val, struct kernel_param *kp)
+{
+	int ret = param_set_int(val, kp);
+	struct MPT2SAS_ADAPTER *ioc;
+
+	if (ret)
+		return ret;
+
+	printk(KERN_INFO "setting logging_level(0x%08x)\n",
+				mpt2sas_fwfault_debug);
+	list_for_each_entry(ioc, &mpt2sas_ioc_list, list)
+		ioc->fwfault_debug = mpt2sas_fwfault_debug;
+	return 0;
+}
+module_param_call(mpt2sas_fwfault_debug, _scsih_set_fwfault_debug,
+    param_get_int, &mpt2sas_fwfault_debug, 0644);
+
 /**
  * _base_fault_reset_work - workq handling ioc fault conditions
  * @work: input argument, used to derive ioc
@@ -177,6 +203,51 @@ mpt2sas_base_stop_watchdog(struct MPT2SAS_ADAPTER *ioc)
 	}
 }
 
+/**
+ * mpt2sas_base_fault_info - verbose translation of firmware FAULT code
+ * @ioc: per adapter object
+ * @fault_code: fault code
+ *
+ * Return nothing.
+ */
+void
+mpt2sas_base_fault_info(struct MPT2SAS_ADAPTER *ioc , u16 fault_code)
+{
+	printk(MPT2SAS_ERR_FMT "fault_state(0x%04x)!\n",
+	    ioc->name, fault_code);
+}
+
+/**
+ * mpt2sas_halt_firmware - halt's mpt controller firmware
+ * @ioc: per adapter object
+ *
+ * For debugging timeout related issues.  Writing 0xCOFFEE00
+ * to the doorbell register will halt controller firmware. With
+ * the purpose to stop both driver and firmware, the enduser can
+ * obtain a ring buffer from controller UART.
+ */
+void
+mpt2sas_halt_firmware(struct MPT2SAS_ADAPTER *ioc)
+{
+	u32 doorbell;
+
+	if (!ioc->fwfault_debug)
+		return;
+
+	dump_stack();
+
+	doorbell = readl(&ioc->chip->Doorbell);
+	if ((doorbell & MPI2_IOC_STATE_MASK) == MPI2_IOC_STATE_FAULT)
+		mpt2sas_base_fault_info(ioc , doorbell);
+	else {
+		writel(0xC0FFEE00, &ioc->chip->Doorbell);
+		printk(MPT2SAS_ERR_FMT "Firmware is halted due to command "
+		    "timeout\n", ioc->name);
+	}
+
+	panic("panic in %s\n", __func__);
+}
+
 #ifdef CONFIG_SCSI_MPT2SAS_LOGGING
 /**
  * _base_sas_ioc_info - verbose translation of the ioc status
@@ -526,20 +597,6 @@ _base_sas_log_info(struct MPT2SAS_ADAPTER *ioc , u32 log_info)
 }
 
 /**
- * mpt2sas_base_fault_info - verbose translation of firmware FAULT code
- * @ioc: pointer to scsi command object
- * @fault_code: fault code
- *
- * Return nothing.
- */
-void
-mpt2sas_base_fault_info(struct MPT2SAS_ADAPTER *ioc , u16 fault_code)
-{
-	printk(MPT2SAS_ERR_FMT "fault_state(0x%04x)!\n",
-	    ioc->name, fault_code);
-}
-
-/**
  * _base_display_reply_info -
  * @ioc: pointer to scsi command object
  * @smid: system request message index
@@ -3684,6 +3741,9 @@ mpt2sas_base_hard_reset_handler(struct MPT2SAS_ADAPTER *ioc, int sleep_flag,
 	dtmprintk(ioc, printk(MPT2SAS_DEBUG_FMT "%s: enter\n", ioc->name,
 	    __func__));
 
+	if (mpt2sas_fwfault_debug)
+		mpt2sas_halt_firmware(ioc);
+
 	spin_lock_irqsave(&ioc->ioc_reset_in_progress_lock, flags);
 	if (ioc->shost_recovery) {
 		spin_unlock_irqrestore(&ioc->ioc_reset_in_progress_lock, flags);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index fa99ff204e46..0c75c0e137f7 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -466,6 +466,7 @@ typedef void (*MPT_ADD_SGE)(void *paddr, u32 flags_length, dma_addr_t dma_addr);
  * @chip_phys: physical addrss prior to mapping
  * @pio_chip: I/O mapped register space
  * @logging_level: see mpt2sas_debug.h
+ * @fwfault_debug: debuging FW timeouts
  * @ir_firmware: IR firmware present
  * @bars: bitmask of BAR's that must be configured
  * @mask_interrupts: ignore interrupt
@@ -587,6 +588,7 @@ struct MPT2SAS_ADAPTER {
 	unsigned long	chip_phys;
 	unsigned long	pio_chip;
 	int		logging_level;
+	int		fwfault_debug;
 	u8		ir_firmware;
 	int		bars;
 	u8		mask_interrupts;
@@ -803,6 +805,8 @@ int mpt2sas_base_scsi_enclosure_processor(struct MPT2SAS_ADAPTER *ioc,
     Mpi2SepReply_t *mpi_reply, Mpi2SepRequest_t *mpi_request);
 void mpt2sas_base_validate_event_type(struct MPT2SAS_ADAPTER *ioc, u32 *event_type);
 
+void mpt2sas_halt_firmware(struct MPT2SAS_ADAPTER *ioc);
+
 /* scsih shared API */
 u8 mpt2sas_scsih_event_callback(struct MPT2SAS_ADAPTER *ioc, u8 msix_index,
     u32 reply);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
index 57d724633906..6901a6706ede 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
@@ -896,6 +896,7 @@ _ctl_do_mpt_command(struct MPT2SAS_ADAPTER *ioc,
 			printk(MPT2SAS_INFO_FMT "issue target reset: handle "
 			    "= (0x%04x)\n", ioc->name,
 			    mpi_request->FunctionDependent1);
+			mpt2sas_halt_firmware(ioc);
 			mutex_lock(&ioc->tm_cmds.mutex);
 			mpt2sas_scsih_issue_tm(ioc,
 			    mpi_request->FunctionDependent1, 0,
@@ -2474,6 +2475,43 @@ _ctl_logging_level_store(struct device *cdev, struct device_attribute *attr,
 static DEVICE_ATTR(logging_level, S_IRUGO | S_IWUSR,
     _ctl_logging_level_show, _ctl_logging_level_store);
 
+/* device attributes */
+/*
+ * _ctl_fwfault_debug_show - show/store fwfault_debug
+ * @cdev - pointer to embedded class device
+ * @buf - the buffer returned
+ *
+ * mpt2sas_fwfault_debug is command line option
+ * A sysfs 'read/write' shost attribute.
+ */
+static ssize_t
+_ctl_fwfault_debug_show(struct device *cdev,
+    struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(cdev);
+	struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", ioc->fwfault_debug);
+}
+static ssize_t
+_ctl_fwfault_debug_store(struct device *cdev,
+    struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(cdev);
+	struct MPT2SAS_ADAPTER *ioc = shost_priv(shost);
+	int val = 0;
+
+	if (sscanf(buf, "%d", &val) != 1)
+		return -EINVAL;
+
+	ioc->fwfault_debug = val;
+	printk(MPT2SAS_INFO_FMT "fwfault_debug=%d\n", ioc->name,
+	    ioc->fwfault_debug);
+	return strlen(buf);
+}
+static DEVICE_ATTR(fwfault_debug, S_IRUGO | S_IWUSR,
+    _ctl_fwfault_debug_show, _ctl_fwfault_debug_store);
+
 struct device_attribute *mpt2sas_host_attrs[] = {
 	&dev_attr_version_fw,
 	&dev_attr_version_bios,
@@ -2487,13 +2525,12 @@ struct device_attribute *mpt2sas_host_attrs[] = {
 	&dev_attr_io_delay,
 	&dev_attr_device_delay,
 	&dev_attr_logging_level,
+	&dev_attr_fwfault_debug,
 	&dev_attr_fw_queue_depth,
 	&dev_attr_host_sas_address,
 	NULL,
 };
 
-/* device attributes */
-
 /**
  * _ctl_device_sas_address_show - sas address
  * @cdev - pointer to embedded class device
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 91d61154a46c..59ea821c2a3c 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -1929,6 +1929,8 @@ _scsih_abort(struct scsi_cmnd *scmd)
 		goto out;
 	}
 
+	mpt2sas_halt_firmware(ioc);
+
 	mutex_lock(&ioc->tm_cmds.mutex);
 	handle = sas_device_priv_data->sas_target->handle;
 	mpt2sas_scsih_issue_tm(ioc, handle, sas_device_priv_data->lun,