ixgbevf: Use igb style interrupt masks instead of ixgbe style

The interrupt registers accessed in ixgbevf are more similar to the igb
style registers than they are to the ixgbe style registers.  As such we
would be better off setting up the code for the EICS, EIMS, EICS, EIAM, and
EIAC like we do in igb instead of ixgbe.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 105 insertions, 146 deletions

diff --git a/drivers/net/ethernet/intel/ixgbevf/defines.h b/drivers/net/ethernet/intel/ixgbevf/defines.h
index e09a6cc..10cede5 100644
--- a/drivers/net/ethernet/intel/ixgbevf/defines.h
+++ b/drivers/net/ethernet/intel/ixgbevf/defines.h
@@ -264,32 +264,9 @@ struct ixgbe_adv_tx_context_desc {
 
 /* Interrupt register bitmasks */
 
-/* Extended Interrupt Cause Read */
-#define IXGBE_EICR_RTX_QUEUE    0x0000FFFF /* RTx Queue Interrupt */
-#define IXGBE_EICR_MAILBOX      0x00080000 /* VF to PF Mailbox Interrupt */
-#define IXGBE_EICR_OTHER        0x80000000 /* Interrupt Cause Active */
-
-/* Extended Interrupt Cause Set */
-#define IXGBE_EICS_RTX_QUEUE    IXGBE_EICR_RTX_QUEUE /* RTx Queue Interrupt */
-#define IXGBE_EICS_MAILBOX      IXGBE_EICR_MAILBOX   /* VF to PF Mailbox Int */
-#define IXGBE_EICS_OTHER        IXGBE_EICR_OTHER     /* INT Cause Active */
-
-/* Extended Interrupt Mask Set */
-#define IXGBE_EIMS_RTX_QUEUE    IXGBE_EICR_RTX_QUEUE /* RTx Queue Interrupt */
-#define IXGBE_EIMS_MAILBOX      IXGBE_EICR_MAILBOX   /* VF to PF Mailbox Int */
-#define IXGBE_EIMS_OTHER        IXGBE_EICR_OTHER     /* INT Cause Active */
-
-/* Extended Interrupt Mask Clear */
-#define IXGBE_EIMC_RTX_QUEUE    IXGBE_EICR_RTX_QUEUE /* RTx Queue Interrupt */
-#define IXGBE_EIMC_MAILBOX      IXGBE_EICR_MAILBOX   /* VF to PF Mailbox Int */
-#define IXGBE_EIMC_OTHER        IXGBE_EICR_OTHER     /* INT Cause Active */
-
-#define IXGBE_EIMS_ENABLE_MASK ( \
-				IXGBE_EIMS_RTX_QUEUE       | \
-				IXGBE_EIMS_MAILBOX         | \
-				IXGBE_EIMS_OTHER)
-
 #define IXGBE_EITR_CNT_WDIS     0x80000000
+#define IXGBE_MAX_EITR		0x00000FF8
+#define IXGBE_MIN_EITR		8
 
 /* Error Codes */
 #define IXGBE_ERR_INVALID_MAC_ADDR              -1
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
index 8bedd0f..f92daca 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf.h
@@ -118,6 +118,8 @@ struct ixgbevf_ring {
 
 struct ixgbevf_ring_container {
 	struct ixgbevf_ring *ring;	/* pointer to linked list of rings */
+	unsigned int total_bytes;	/* total bytes processed this int */
+	unsigned int total_packets;	/* total packets processed this int */
 	u8 count;			/* total number of rings in vector */
 	u8 itr;				/* current ITR setting for ring */
 };
@@ -131,13 +133,25 @@ struct ixgbevf_ring_container {
  */
 struct ixgbevf_q_vector {
 	struct ixgbevf_adapter *adapter;
+	u16 v_idx;		/* index of q_vector within array, also used for
+				 * finding the bit in EICR and friends that
+				 * represents the vector for this ring */
+	u16 itr;		/* Interrupt throttle rate written to EITR */
 	struct napi_struct napi;
 	struct ixgbevf_ring_container rx, tx;
-	u32 eitr;
-	int v_idx;	  /* vector index in list */
 	char name[IFNAMSIZ + 9];
 };
 
+/*
+ * microsecond values for various ITR rates shifted by 2 to fit itr register
+ * with the first 3 bits reserved 0
+ */
+#define IXGBE_MIN_RSC_ITR	24
+#define IXGBE_100K_ITR		40
+#define IXGBE_20K_ITR		200
+#define IXGBE_10K_ITR		400
+#define IXGBE_8K_ITR		500
+
 /* Helper macros to switch between ints/sec and what the register uses.
  * And yes, it's the same math going both ways.  The lowest value
  * supported by all of the ixgbe hardware is 8.
@@ -176,12 +190,16 @@ struct ixgbevf_adapter {
 	struct ixgbevf_q_vector *q_vector[MAX_MSIX_Q_VECTORS];
 
 	/* Interrupt Throttle Rate */
-	u32 itr_setting;
+	u16 rx_itr_setting;
+	u16 tx_itr_setting;
+
+	/* interrupt masks */
+	u32 eims_enable_mask;
+	u32 eims_other;
 
 	/* TX */
 	struct ixgbevf_ring *tx_ring;	/* One per active queue */
 	int num_tx_queues;
-	u16 tx_itr_setting;
 	u64 restart_queue;
 	u64 hw_csum_tx_good;
 	u64 lsc_int;
@@ -192,7 +210,6 @@ struct ixgbevf_adapter {
 	/* RX */
 	struct ixgbevf_ring *rx_ring;	/* One per active queue */
 	int num_rx_queues;
-	u16 rx_itr_setting;
 	u64 hw_csum_rx_error;
 	u64 hw_rx_no_dma_resources;
 	u64 hw_csum_rx_good;
@@ -265,7 +282,7 @@ extern void ixgbevf_free_rx_resources(struct ixgbevf_adapter *,
 extern void ixgbevf_free_tx_resources(struct ixgbevf_adapter *,
 				      struct ixgbevf_ring *);
 extern void ixgbevf_update_stats(struct ixgbevf_adapter *adapter);
-
+void ixgbevf_write_eitr(struct ixgbevf_q_vector *);
 extern int ethtool_ioctl(struct ifreq *ifr);
 
 extern void ixgbe_napi_add_all(struct ixgbevf_adapter *adapter);
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 628643b..8e022c6 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -98,8 +98,6 @@ MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
 
 /* forward decls */
 static void ixgbevf_set_itr(struct ixgbevf_q_vector *q_vector);
-static void ixgbevf_write_eitr(struct ixgbevf_adapter *adapter, int v_idx,
-			       u32 itr_reg);
 
 static inline void ixgbevf_release_rx_desc(struct ixgbe_hw *hw,
 					   struct ixgbevf_ring *rx_ring,
@@ -385,13 +383,11 @@ no_buffers:
 }
 
 static inline void ixgbevf_irq_enable_queues(struct ixgbevf_adapter *adapter,
-					     u64 qmask)
+					     u32 qmask)
 {
-	u32 mask;
 	struct ixgbe_hw *hw = &adapter->hw;
 
-	mask = (qmask & 0xFFFFFFFF);
-	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, mask);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, qmask);
 }
 
 static bool ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
@@ -561,11 +557,10 @@ static int ixgbevf_poll(struct napi_struct *napi, int budget)
 static void ixgbevf_configure_msix(struct ixgbevf_adapter *adapter)
 {
 	struct ixgbevf_q_vector *q_vector;
-	struct ixgbe_hw *hw = &adapter->hw;
 	int q_vectors, v_idx;
-	u32 mask;
 
 	q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
+	adapter->eims_enable_mask = 0;
 
 	/*
 	 * Populate the IVAR table and set the ITR values to the
@@ -581,22 +576,30 @@ static void ixgbevf_configure_msix(struct ixgbevf_adapter *adapter)
 		ixgbevf_for_each_ring(ring, q_vector->tx)
 			ixgbevf_set_ivar(adapter, 1, ring->reg_idx, v_idx);
 
-		/* if this is a tx only vector halve the interrupt rate */
-		if (q_vector->tx.ring && !q_vector->rx.ring)
-			q_vector->eitr = (adapter->eitr_param >> 1);
-		else if (q_vector->rx.ring)
-			/* rx only */
-			q_vector->eitr = adapter->eitr_param;
+		if (q_vector->tx.ring && !q_vector->rx.ring) {
+			/* tx only vector */
+			if (adapter->tx_itr_setting == 1)
+				q_vector->itr = IXGBE_10K_ITR;
+			else
+				q_vector->itr = adapter->tx_itr_setting;
+		} else {
+			/* rx or rx/tx vector */
+			if (adapter->rx_itr_setting == 1)
+				q_vector->itr = IXGBE_20K_ITR;
+			else
+				q_vector->itr = adapter->rx_itr_setting;
+		}
+
+		/* add q_vector eims value to global eims_enable_mask */
+		adapter->eims_enable_mask |= 1 << v_idx;
 
-		ixgbevf_write_eitr(adapter, v_idx, q_vector->eitr);
+		ixgbevf_write_eitr(q_vector);
 	}
 
 	ixgbevf_set_ivar(adapter, -1, 1, v_idx);
-
-	/* set up to autoclear timer, and the vectors */
-	mask = IXGBE_EIMS_ENABLE_MASK;
-	mask &= ~IXGBE_EIMS_OTHER;
-	IXGBE_WRITE_REG(hw, IXGBE_VTEIAC, mask);
+	/* setup eims_other and add value to global eims_enable_mask */
+	adapter->eims_other = 1 << v_idx;
+	adapter->eims_enable_mask |= adapter->eims_other;
 }
 
 enum latency_range {
@@ -608,11 +611,8 @@ enum latency_range {
 
 /**
  * ixgbevf_update_itr - update the dynamic ITR value based on statistics
- * @adapter: pointer to adapter
- * @eitr: eitr setting (ints per sec) to give last timeslice
- * @itr_setting: current throttle rate in ints/second
- * @packets: the number of packets during this measurement interval
- * @bytes: the number of bytes during this measurement interval
+ * @q_vector: structure containing interrupt and ring information
+ * @ring_container: structure containing ring performance data
  *
  *      Stores a new ITR value based on packets and byte
  *      counts during the last interrupt.  The advantage of per interrupt
@@ -622,17 +622,17 @@ enum latency_range {
  *      on testing data as well as attempting to minimize response time
  *      while increasing bulk throughput.
  **/
-static u8 ixgbevf_update_itr(struct ixgbevf_adapter *adapter,
-			     u32 eitr, u8 itr_setting,
-			     int packets, int bytes)
+static void ixgbevf_update_itr(struct ixgbevf_q_vector *q_vector,
+			       struct ixgbevf_ring_container *ring_container)
 {
-	unsigned int retval = itr_setting;
+	int bytes = ring_container->total_bytes;
+	int packets = ring_container->total_packets;
 	u32 timepassed_us;
 	u64 bytes_perint;
+	u8 itr_setting = ring_container->itr;
 
 	if (packets == 0)
-		goto update_itr_done;
-
+		return;
 
 	/* simple throttlerate management
 	 *    0-20MB/s lowest (100000 ints/s)
@@ -640,46 +640,48 @@ static u8 ixgbevf_update_itr(struct ixgbevf_adapter *adapter,
 	 *  100-1249MB/s bulk (8000 ints/s)
 	 */
 	/* what was last interrupt timeslice? */
-	timepassed_us = 1000000/eitr;
+	timepassed_us = q_vector->itr >> 2;
 	bytes_perint = bytes / timepassed_us; /* bytes/usec */
 
 	switch (itr_setting) {
 	case lowest_latency:
 		if (bytes_perint > 10)
-			retval = low_latency;
+			itr_setting = low_latency;
 		break;
 	case low_latency:
 		if (bytes_perint > 20)
-			retval = bulk_latency;
+			itr_setting = bulk_latency;
 		else if (bytes_perint <= 10)
-			retval = lowest_latency;
+			itr_setting = lowest_latency;
 		break;
 	case bulk_latency:
 		if (bytes_perint <= 20)
-			retval = low_latency;
+			itr_setting = low_latency;
 		break;
 	}
 
-update_itr_done:
-	return retval;
+	/* clear work counters since we have the values we need */
+	ring_container->total_bytes = 0;
+	ring_container->total_packets = 0;
+
+	/* write updated itr to ring container */
+	ring_container->itr = itr_setting;
 }
 
 /**
  * ixgbevf_write_eitr - write VTEITR register in hardware specific way
- * @adapter: pointer to adapter struct
- * @v_idx: vector index into q_vector array
- * @itr_reg: new value to be written in *register* format, not ints/s
+ * @q_vector: structure containing interrupt and ring information
  *
  * This function is made to be called by ethtool and by the driver
  * when it needs to update VTEITR registers at runtime.  Hardware
  * specific quirks/differences are taken care of here.
  */
-static void ixgbevf_write_eitr(struct ixgbevf_adapter *adapter, int v_idx,
-			       u32 itr_reg)
+void ixgbevf_write_eitr(struct ixgbevf_q_vector *q_vector)
 {
+	struct ixgbevf_adapter *adapter = q_vector->adapter;
 	struct ixgbe_hw *hw = &adapter->hw;
-
-	itr_reg = EITR_INTS_PER_SEC_TO_REG(itr_reg);
+	int v_idx = q_vector->v_idx;
+	u32 itr_reg = q_vector->itr & IXGBE_MAX_EITR;
 
 	/*
 	 * set the WDIS bit to not clear the timer bits and cause an
@@ -692,59 +694,37 @@ static void ixgbevf_write_eitr(struct ixgbevf_adapter *adapter, int v_idx,
 
 static void ixgbevf_set_itr(struct ixgbevf_q_vector *q_vector)
 {
-	struct ixgbevf_adapter *adapter = q_vector->adapter;
-	u32 new_itr;
-	u8 current_itr, ret_itr;
-	int v_idx = q_vector->v_idx;
-	struct ixgbevf_ring *rx_ring, *tx_ring;
-
-	ixgbevf_for_each_ring(tx_ring, q_vector->tx) {
-		ret_itr = ixgbevf_update_itr(adapter, q_vector->eitr,
-					     q_vector->tx.itr,
-					     tx_ring->total_packets,
-					     tx_ring->total_bytes);
-		/* if the result for this queue would decrease interrupt
-		 * rate for this vector then use that result */
-		q_vector->tx.itr = ((q_vector->tx.itr > ret_itr) ?
-				    q_vector->tx.itr - 1 : ret_itr);
-	}
-
-	ixgbevf_for_each_ring(rx_ring, q_vector->rx) {
-		ret_itr = ixgbevf_update_itr(adapter, q_vector->eitr,
-					     q_vector->rx.itr,
-					     rx_ring->total_packets,
-					     rx_ring->total_bytes);
-		/* if the result for this queue would decrease interrupt
-		 * rate for this vector then use that result */
-		q_vector->rx.itr = ((q_vector->rx.itr > ret_itr) ?
-				    q_vector->rx.itr - 1 : ret_itr);
-	}
+	u32 new_itr = q_vector->itr;
+	u8 current_itr;
+
+	ixgbevf_update_itr(q_vector, &q_vector->tx);
+	ixgbevf_update_itr(q_vector, &q_vector->rx);
 
 	current_itr = max(q_vector->rx.itr, q_vector->tx.itr);
 
 	switch (current_itr) {
 	/* counts and packets in update_itr are dependent on these numbers */
 	case lowest_latency:
-		new_itr = 100000;
+		new_itr = IXGBE_100K_ITR;
 		break;
 	case low_latency:
-		new_itr = 20000; /* aka hwitr = ~200 */
+		new_itr = IXGBE_20K_ITR;
 		break;
 	case bulk_latency:
 	default:
-		new_itr = 8000;
+		new_itr = IXGBE_8K_ITR;
 		break;
 	}
 
-	if (new_itr != q_vector->eitr) {
-		u32 itr_reg;
-
-		/* save the algorithm value here, not the smoothed one */
-		q_vector->eitr = new_itr;
+	if (new_itr != q_vector->itr) {
 		/* do an exponential smoothing */
-		new_itr = ((q_vector->eitr * 90)/100) + ((new_itr * 10)/100);
-		itr_reg = EITR_INTS_PER_SEC_TO_REG(new_itr);
-		ixgbevf_write_eitr(adapter, v_idx, itr_reg);
+		new_itr = (10 * new_itr * q_vector->itr) /
+			  ((9 * new_itr) + q_vector->itr);
+
+		/* save the algorithm value here */
+		q_vector->itr = new_itr;
+
+		ixgbevf_write_eitr(q_vector);
 	}
 }
 
@@ -752,13 +732,9 @@ static irqreturn_t ixgbevf_msix_mbx(int irq, void *data)
 {
 	struct ixgbevf_adapter *adapter = data;
 	struct ixgbe_hw *hw = &adapter->hw;
-	u32 eicr;
 	u32 msg;
 	bool got_ack = false;
 
-	eicr = IXGBE_READ_REG(hw, IXGBE_VTEICS);
-	IXGBE_WRITE_REG(hw, IXGBE_VTEICR, eicr);
-
 	if (!hw->mbx.ops.check_for_ack(hw))
 		got_ack = true;
 
@@ -787,6 +763,8 @@ static irqreturn_t ixgbevf_msix_mbx(int irq, void *data)
 	if (got_ack)
 		hw->mbx.v2p_mailbox |= IXGBE_VFMAILBOX_PFACK;
 
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, adapter->eims_other);
+
 	return IRQ_HANDLED;
 }
 
@@ -799,11 +777,8 @@ static irqreturn_t ixgbevf_msix_mbx(int irq, void *data)
 static irqreturn_t ixgbevf_msix_clean_rings(int irq, void *data)
 {
 	struct ixgbevf_q_vector *q_vector = data;
-	struct ixgbevf_adapter  *adapter = q_vector->adapter;
-	struct ixgbe_hw *hw = &adapter->hw;
 
-	/* disable interrupts on this vector only */
-	IXGBE_WRITE_REG(hw, IXGBE_VTEIMC, 1 << q_vector->v_idx);
+	/* EIAM disabled interrupts (on this vector) for us */
 	if (q_vector->rx.ring || q_vector->tx.ring)
 		napi_schedule(&q_vector->napi);
 
@@ -967,7 +942,6 @@ static inline void ixgbevf_reset_q_vectors(struct ixgbevf_adapter *adapter)
 		q_vector->tx.ring = NULL;
 		q_vector->rx.count = 0;
 		q_vector->tx.count = 0;
-		q_vector->eitr = adapter->eitr_param;
 	}
 }
 
@@ -1020,10 +994,12 @@ static void ixgbevf_free_irq(struct ixgbevf_adapter *adapter)
  **/
 static inline void ixgbevf_irq_disable(struct ixgbevf_adapter *adapter)
 {
-	int i;
 	struct ixgbe_hw *hw = &adapter->hw;
+	int i;
 
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIAM, 0);
 	IXGBE_WRITE_REG(hw, IXGBE_VTEIMC, ~0);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIAC, 0);
 
 	IXGBE_WRITE_FLUSH(hw);
 
@@ -1035,23 +1011,13 @@ static inline void ixgbevf_irq_disable(struct ixgbevf_adapter *adapter)
  * ixgbevf_irq_enable - Enable default interrupt generation settings
  * @adapter: board private structure
  **/
-static inline void ixgbevf_irq_enable(struct ixgbevf_adapter *adapter,
-				      bool queues, bool flush)
+static inline void ixgbevf_irq_enable(struct ixgbevf_adapter *adapter)
 {
 	struct ixgbe_hw *hw = &adapter->hw;
-	u32 mask;
-	u64 qmask;
-
-	mask = (IXGBE_EIMS_ENABLE_MASK & ~IXGBE_EIMS_RTX_QUEUE);
-	qmask = ~0;
-
-	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, mask);
-
-	if (queues)
-		ixgbevf_irq_enable_queues(adapter, qmask);
 
-	if (flush)
-		IXGBE_WRITE_FLUSH(hw);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIAM, adapter->eims_enable_mask);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIAC, adapter->eims_enable_mask);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, adapter->eims_enable_mask);
 }
 
 /**
@@ -1414,7 +1380,7 @@ void ixgbevf_up(struct ixgbevf_adapter *adapter)
 	/* clear any pending interrupts, may auto mask */
 	IXGBE_READ_REG(hw, IXGBE_VTEICR);
 
-	ixgbevf_irq_enable(adapter, true, true);
+	ixgbevf_irq_enable(adapter);
 }
 
 /**
@@ -1783,7 +1749,6 @@ static int ixgbevf_alloc_q_vectors(struct ixgbevf_adapter *adapter)
 			goto err_out;
 		q_vector->adapter = adapter;
 		q_vector->v_idx = q_idx;
-		q_vector->eitr = adapter->eitr_param;
 		netif_napi_add(adapter->netdev, &q_vector->napi,
 			       ixgbevf_poll, 64);
 		adapter->q_vector[q_idx] = q_vector;
@@ -1932,8 +1897,8 @@ static int __devinit ixgbevf_sw_init(struct ixgbevf_adapter *adapter)
 	}
 
 	/* Enable dynamic interrupt throttling rates */
-	adapter->eitr_param = 20000;
-	adapter->itr_setting = 1;
+	adapter->rx_itr_setting = 1;
+	adapter->tx_itr_setting = 1;
 
 	/* set default ring sizes */
 	adapter->tx_ring_count = IXGBEVF_DEFAULT_TXD;
@@ -1998,7 +1963,7 @@ static void ixgbevf_watchdog(unsigned long data)
 {
 	struct ixgbevf_adapter *adapter = (struct ixgbevf_adapter *)data;
 	struct ixgbe_hw *hw = &adapter->hw;
-	u64 eics = 0;
+	u32 eics = 0;
 	int i;
 
 	/*
@@ -2013,10 +1978,10 @@ static void ixgbevf_watchdog(unsigned long data)
 	for (i = 0; i < adapter->num_msix_vectors - NON_Q_VECTORS; i++) {
 		struct ixgbevf_q_vector *qv = adapter->q_vector[i];
 		if (qv->rx.ring || qv->tx.ring)
-			eics |= (1 << i);
+			eics |= 1 << i;
 	}
 
-	IXGBE_WRITE_REG(hw, IXGBE_VTEICS, (u32)eics);
+	IXGBE_WRITE_REG(hw, IXGBE_VTEICS, eics);
 
 watchdog_short_circuit:
 	schedule_work(&adapter->watchdog_task);
@@ -2389,7 +2354,7 @@ static int ixgbevf_open(struct net_device *netdev)
 	if (err)
 		goto err_req_irq;
 
-	ixgbevf_irq_enable(adapter, true, true);
+	ixgbevf_irq_enable(adapter);
 
 	return 0;