mei: expose hardware power gating state to mei layer

Since the runtime pm and the internal power gating
cannot be in complete sync in regards to I/O
operations, we need to expose the device
hardware internal power gating state to mei layer

2. We add pg_state handler that translate the hw
internal pg state to mei layer

2. We add power gating event variable to keep
power track of power gating transitions

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 32 insertions, 11 deletions

diff --git a/drivers/misc/mei/hw-txe.c b/drivers/misc/mei/hw-txe.c
index 49f197a956c9..4a6f567f4f80 100644
--- a/drivers/misc/mei/hw-txe.c
+++ b/drivers/misc/mei/hw-txe.c
@@ -158,7 +158,7 @@ static bool mei_txe_aliveness_set(struct mei_device *dev, u32 req)
 	dev_dbg(&dev->pdev->dev, "Aliveness current=%d request=%d\n",
 				hw->aliveness, req);
 	if (do_req) {
-		hw->recvd_aliveness = false;
+		dev->pg_event = MEI_PG_EVENT_WAIT;
 		mei_txe_br_reg_write(hw, SICR_HOST_ALIVENESS_REQ_REG, req);
 	}
 	return do_req;
@@ -213,6 +213,7 @@ static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
 	do {
 		hw->aliveness = mei_txe_aliveness_get(dev);
 		if (hw->aliveness == expected) {
+			dev->pg_event = MEI_PG_EVENT_IDLE;
 			dev_dbg(&dev->pdev->dev,
 				"aliveness settled after %d msecs\n", t);
 			return t;
@@ -223,6 +224,7 @@ static int mei_txe_aliveness_poll(struct mei_device *dev, u32 expected)
 		t += MSEC_PER_SEC / 5;
 	} while (t < SEC_ALIVENESS_WAIT_TIMEOUT);
 
+	dev->pg_event = MEI_PG_EVENT_IDLE;
 	dev_err(&dev->pdev->dev, "aliveness timed out\n");
 	return -ETIME;
 }
@@ -249,19 +251,22 @@ static int mei_txe_aliveness_wait(struct mei_device *dev, u32 expected)
 		return 0;
 
 	mutex_unlock(&dev->device_lock);
-	err = wait_event_timeout(hw->wait_aliveness,
-			hw->recvd_aliveness, timeout);
+	err = wait_event_timeout(hw->wait_aliveness_resp,
+			dev->pg_event == MEI_PG_EVENT_RECEIVED, timeout);
 	mutex_lock(&dev->device_lock);
 
 	hw->aliveness = mei_txe_aliveness_get(dev);
 	ret = hw->aliveness == expected ? 0 : -ETIME;
 
 	if (ret)
-		dev_err(&dev->pdev->dev, "aliveness timed out");
+		dev_warn(&dev->pdev->dev, "aliveness timed out = %ld aliveness = %d event = %d\n",
+			err, hw->aliveness, dev->pg_event);
 	else
-		dev_dbg(&dev->pdev->dev, "aliveness settled after %d msecs\n",
-				jiffies_to_msecs(timeout - err));
-	hw->recvd_aliveness = false;
+		dev_dbg(&dev->pdev->dev, "aliveness settled after = %d msec aliveness = %d event = %d\n",
+			jiffies_to_msecs(timeout - err),
+			hw->aliveness, dev->pg_event);
+
+	dev->pg_event = MEI_PG_EVENT_IDLE;
 	return ret;
 }
 
@@ -292,6 +297,20 @@ static bool mei_txe_pg_is_enabled(struct mei_device *dev)
 }
 
 /**
+ * mei_txe_pg_state  - translate aliveness register value
+ *   to the mei power gating state
+ *
+ * @dev: the device structure
+ *
+ * returns: MEI_PG_OFF if aliveness is on and MEI_PG_ON otherwise
+ */
+static inline enum mei_pg_state mei_txe_pg_state(struct mei_device *dev)
+{
+	struct mei_txe_hw *hw = to_txe_hw(dev);
+	return hw->aliveness ? MEI_PG_OFF : MEI_PG_ON;
+}
+
+/**
  * mei_txe_input_ready_interrupt_enable - sets the Input Ready Interrupt
  *
  * @dev: the device structure
@@ -972,9 +991,9 @@ irqreturn_t mei_txe_irq_thread_handler(int irq, void *dev_id)
 		/* Clear the interrupt cause */
 		dev_dbg(&dev->pdev->dev,
 			"Aliveness Interrupt: Status: %d\n", hw->aliveness);
-		hw->recvd_aliveness = true;
-		if (waitqueue_active(&hw->wait_aliveness))
-			wake_up(&hw->wait_aliveness);
+		dev->pg_event = MEI_PG_EVENT_RECEIVED;
+		if (waitqueue_active(&hw->wait_aliveness_resp))
+			wake_up(&hw->wait_aliveness_resp);
 	}
 
 
@@ -1024,6 +1043,8 @@ static const struct mei_hw_ops mei_txe_hw_ops = {
 
 	.host_is_ready = mei_txe_host_is_ready,
 
+	.pg_state = mei_txe_pg_state,
+
 	.hw_is_ready = mei_txe_hw_is_ready,
 	.hw_reset = mei_txe_hw_reset,
 	.hw_config = mei_txe_hw_config,
@@ -1069,7 +1090,7 @@ struct mei_device *mei_txe_dev_init(struct pci_dev *pdev)
 
 	hw = to_txe_hw(dev);
 
-	init_waitqueue_head(&hw->wait_aliveness);
+	init_waitqueue_head(&hw->wait_aliveness_resp);
 
 	dev->ops = &mei_txe_hw_ops;