Merge tag 'isci-for-3.5' into misc

isci update for 3.5

1/ Rework remote-node-context (RNC) handling for proper management of
   the silicon state machine in error handling and hot-plug conditions.
   Further details below, suffice to say if the RNC is mismanaged the
   silicon state machines may lock up.

2/ Refactor the initialization code to be reused for suspend/resume support

3/ Miscellaneous bug fixes to address discovery issues and hardware
   compatibility.

RNC rework details from Jeff Skirvin:

In the controller, devices as they appear on a SAS domain (or
direct-attached SATA devices) are represented by memory structures known
as "Remote Node Contexts" (RNCs).  These structures are transferred from
main memory to the controller using a set of register commands; these
commands include setting up the context ("posting"), removing the
context ("invalidating"), and commands to control the scheduling of
commands and connections to that remote device ("suspensions" and
"resumptions").  There is a similar path to control RNC scheduling from
the protocol engine, which interprets the results of command and data
transmission and reception.

In general, the controller chooses among non-suspended RNCs to find one
that has work requiring scheduling the transmission of command and data
frames to a target.  Likewise, when a target tries to return data back
to the initiator, the state of the RNC is used by the controller to
determine how to treat the incoming request. As an example, if the RNC
is in the state "TX/RX Suspended", incoming SSP connection requests from
the target will be rejected by the controller hardware.  When an RNC is
"TX Suspended", it will not be selected by the controller hardware to
start outgoing command or data operations (with certain priority-based
exceptions).

As mentioned above, there are two sources for management of the RNC
states: commands from driver software, and the result of transmission
and reception conditions of commands and data signaled by the controller
hardware.  As an example of the latter, if an outgoing SSP command ends
with a OPEN_REJECT(BAD_DESTINATION) status, the RNC state will
transition to the "TX Suspended" state, and this is signaled by the
controller hardware in the status to the completion of the pending
command as well as signaled in a controller hardware event.  Examples of
the former are included in the patch changelogs.

Driver software is required to suspend the RNC in a "TX/RX Suspended"
condition before any outstanding commands can be terminated.  Failure to
guarantee this can lead to a complete hardware hang condition.  Earlier
versions of the driver software did not guarantee that an RNC was
correctly managed before I/O termination, and so operated in an unsafe
way.

Further, the driver performed unnecessary contortions to preserve the
remote device command state and so was more complicated than it needed
to be.  A simplifying driver assumption is that once an I/O has entered
the error handler path without having completed in the target, the
requirement on the driver is that all use of the sas_task must end.
Beyond that, recovery of operation is dependent on libsas and other
components to reset, rediscover and reconfigure the device before normal
operation can restart.  In the driver, this simplifying assumption meant
that the RNC management could be reduced to entry into the suspended
state, terminating the targeted I/O request, and resuming the RNC as
needed for device-specific management such as an SSP Abort Task or LUN
Reset Management request.

1 files changed, 37 insertions, 31 deletions

diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c
index 5fada73b71f..2fb85bf7544 100644
--- a/drivers/scsi/isci/port.c
+++ b/drivers/scsi/isci/port.c
@@ -184,7 +184,7 @@ static void isci_port_link_up(struct isci_host *isci_host,
 
 	sci_port_get_properties(iport, &properties);
 
-	if (iphy->protocol == SCIC_SDS_PHY_PROTOCOL_SATA) {
+	if (iphy->protocol == SAS_PROTOCOL_SATA) {
 		u64 attached_sas_address;
 
 		iphy->sas_phy.oob_mode = SATA_OOB_MODE;
@@ -204,7 +204,7 @@ static void isci_port_link_up(struct isci_host *isci_host,
 
 		memcpy(&iphy->sas_phy.attached_sas_addr,
 		       &attached_sas_address, sizeof(attached_sas_address));
-	} else if (iphy->protocol == SCIC_SDS_PHY_PROTOCOL_SAS) {
+	} else if (iphy->protocol == SAS_PROTOCOL_SSP) {
 		iphy->sas_phy.oob_mode = SAS_OOB_MODE;
 		iphy->sas_phy.frame_rcvd_size = sizeof(struct sas_identify_frame);
 
@@ -251,10 +251,10 @@ static void isci_port_link_down(struct isci_host *isci_host,
 		if (isci_phy->sas_phy.port &&
 		    isci_phy->sas_phy.port->num_phys == 1) {
 			/* change the state for all devices on this port.  The
-			 * next task sent to this device will be returned as
-			 * SAS_TASK_UNDELIVERED, and the scsi mid layer will
-			 * remove the target
-			 */
+			* next task sent to this device will be returned as
+			* SAS_TASK_UNDELIVERED, and the scsi mid layer will
+			* remove the target
+			*/
 			list_for_each_entry(isci_device,
 					    &isci_port->remote_dev_list,
 					    node) {
@@ -517,7 +517,7 @@ void sci_port_get_attached_sas_address(struct isci_port *iport, struct sci_sas_a
 	 */
 	iphy = sci_port_get_a_connected_phy(iport);
 	if (iphy) {
-		if (iphy->protocol != SCIC_SDS_PHY_PROTOCOL_SATA) {
+		if (iphy->protocol != SAS_PROTOCOL_SATA) {
 			sci_phy_get_attached_sas_address(iphy, sas);
 		} else {
 			sci_phy_get_sas_address(iphy, sas);
@@ -624,7 +624,7 @@ static void sci_port_activate_phy(struct isci_port *iport,
 {
 	struct isci_host *ihost = iport->owning_controller;
 
-	if (iphy->protocol != SCIC_SDS_PHY_PROTOCOL_SATA && (flags & PF_RESUME))
+	if (iphy->protocol != SAS_PROTOCOL_SATA && (flags & PF_RESUME))
 		sci_phy_resume(iphy);
 
 	iport->active_phy_mask |= 1 << iphy->phy_index;
@@ -751,12 +751,10 @@ static bool sci_port_is_wide(struct isci_port *iport)
  * wide ports and direct attached phys.  Since there are no wide ported SATA
  * devices this could become an invalid port configuration.
  */
-bool sci_port_link_detected(
-	struct isci_port *iport,
-	struct isci_phy *iphy)
+bool sci_port_link_detected(struct isci_port *iport, struct isci_phy *iphy)
 {
 	if ((iport->logical_port_index != SCIC_SDS_DUMMY_PORT) &&
-	    (iphy->protocol == SCIC_SDS_PHY_PROTOCOL_SATA)) {
+	    (iphy->protocol == SAS_PROTOCOL_SATA)) {
 		if (sci_port_is_wide(iport)) {
 			sci_port_invalid_link_up(iport, iphy);
 			return false;
@@ -1201,6 +1199,8 @@ enum sci_status sci_port_add_phy(struct isci_port *iport,
 	enum sci_status status;
 	enum sci_port_states state;
 
+	sci_port_bcn_enable(iport);
+
 	state = iport->sm.current_state_id;
 	switch (state) {
 	case SCI_PORT_STOPPED: {
@@ -1548,6 +1548,29 @@ static void sci_port_failed_state_enter(struct sci_base_state_machine *sm)
 	isci_port_hard_reset_complete(iport, SCI_FAILURE_TIMEOUT);
 }
 
+void sci_port_set_hang_detection_timeout(struct isci_port *iport, u32 timeout)
+{
+	int phy_index;
+	u32 phy_mask = iport->active_phy_mask;
+
+	if (timeout)
+		++iport->hang_detect_users;
+	else if (iport->hang_detect_users > 1)
+		--iport->hang_detect_users;
+	else
+		iport->hang_detect_users = 0;
+
+	if (timeout || (iport->hang_detect_users == 0)) {
+		for (phy_index = 0; phy_index < SCI_MAX_PHYS; phy_index++) {
+			if ((phy_mask >> phy_index) & 1) {
+				writel(timeout,
+				       &iport->phy_table[phy_index]
+					  ->link_layer_registers
+					  ->link_layer_hang_detection_timeout);
+			}
+		}
+	}
+}
 /* --------------------------------------------------------------------------- */
 
 static const struct sci_base_state sci_port_state_table[] = {
@@ -1596,6 +1619,7 @@ void sci_port_construct(struct isci_port *iport, u8 index,
 
 	iport->started_request_count = 0;
 	iport->assigned_device_count = 0;
+	iport->hang_detect_users = 0;
 
 	iport->reserved_rni = SCU_DUMMY_INDEX;
 	iport->reserved_tag = SCI_CONTROLLER_INVALID_IO_TAG;
@@ -1608,13 +1632,6 @@ void sci_port_construct(struct isci_port *iport, u8 index,
 		iport->phy_table[index] = NULL;
 }
 
-void isci_port_init(struct isci_port *iport, struct isci_host *ihost, int index)
-{
-	INIT_LIST_HEAD(&iport->remote_dev_list);
-	INIT_LIST_HEAD(&iport->domain_dev_list);
-	iport->isci_host = ihost;
-}
-
 void sci_port_broadcast_change_received(struct isci_port *iport, struct isci_phy *iphy)
 {
 	struct isci_host *ihost = iport->owning_controller;
@@ -1671,17 +1688,6 @@ int isci_port_perform_hard_reset(struct isci_host *ihost, struct isci_port *ipor
 			__func__, iport, status);
 
 	}
-
-	/* If the hard reset for the port has failed, consider this
-	 * the same as link failures on all phys in the port.
-	 */
-	if (ret != TMF_RESP_FUNC_COMPLETE) {
-
-		dev_err(&ihost->pdev->dev,
-			"%s: iport = %p; hard reset failed "
-			"(0x%x) - driving explicit link fail for all phys\n",
-			__func__, iport, iport->hard_reset_status);
-	}
 	return ret;
 }
 
@@ -1740,7 +1746,7 @@ void isci_port_formed(struct asd_sas_phy *phy)
 	struct isci_host *ihost = phy->ha->lldd_ha;
 	struct isci_phy *iphy = to_iphy(phy);
 	struct asd_sas_port *port = phy->port;
-	struct isci_port *iport;
+	struct isci_port *iport = NULL;
 	unsigned long flags;
 	int i;