i40e: factor out queue control from i40e_vsi_control_(tx|rx)

A future patch will need to be able to handle controlling queues without
waiting until all VSIs are handled. Factor out the direct queue
modification so that we can easily re-use this code. The result is also
a bit easier to read since we don't embed multiple single-letter loop
counters.

Change-ID: Id923cbfa43127b1c24d8ed4f809b1012c736d9ac
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 89 insertions, 50 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 5c2ceb247959..2bf5bb1b4627 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -3919,6 +3919,8 @@ static void i40e_netpoll(struct net_device *netdev)
 }
 #endif
 
+#define I40E_QTX_ENA_WAIT_COUNT 50
+
 /**
  * i40e_pf_txq_wait - Wait for a PF's Tx queue to be enabled or disabled
  * @pf: the PF being configured
@@ -3949,6 +3951,50 @@ static int i40e_pf_txq_wait(struct i40e_pf *pf, int pf_q, bool enable)
 }
 
 /**
+ * i40e_control_tx_q - Start or stop a particular Tx queue
+ * @pf: the PF structure
+ * @pf_q: the PF queue to configure
+ * @enable: start or stop the queue
+ *
+ * This function enables or disables a single queue. Note that any delay
+ * required after the operation is expected to be handled by the caller of
+ * this function.
+ **/
+static void i40e_control_tx_q(struct i40e_pf *pf, int pf_q, bool enable)
+{
+        struct i40e_hw *hw = &pf->hw;
+        u32 tx_reg;
+        int i;
+
+        /* warn the TX unit of coming changes */
+        i40e_pre_tx_queue_cfg(&pf->hw, pf_q, enable);
+        if (!enable)
+                usleep_range(10, 20);
+
+        for (i = 0; i < I40E_QTX_ENA_WAIT_COUNT; i++) {
+                tx_reg = rd32(hw, I40E_QTX_ENA(pf_q));
+                if (((tx_reg >> I40E_QTX_ENA_QENA_REQ_SHIFT) & 1) ==
+                    ((tx_reg >> I40E_QTX_ENA_QENA_STAT_SHIFT) & 1))
+                        break;
+                usleep_range(1000, 2000);
+        }
+
+        /* Skip if the queue is already in the requested state */
+        if (enable == !!(tx_reg & I40E_QTX_ENA_QENA_STAT_MASK))
+                return;
+
+        /* turn on/off the queue */
+        if (enable) {
+                wr32(hw, I40E_QTX_HEAD(pf_q), 0);
+                tx_reg |= I40E_QTX_ENA_QENA_REQ_MASK;
+        } else {
+                tx_reg &= ~I40E_QTX_ENA_QENA_REQ_MASK;
+        }
+
+        wr32(hw, I40E_QTX_ENA(pf_q), tx_reg);
+}
+
+/**
  * i40e_vsi_control_tx - Start or stop a VSI's rings
  * @vsi: the VSI being configured
  * @enable: start or stop the rings
@@ -3956,39 +4002,13 @@ static int i40e_pf_txq_wait(struct i40e_pf *pf, int pf_q, bool enable)
 static int i40e_vsi_control_tx(struct i40e_vsi *vsi, bool enable)
 {
         struct i40e_pf *pf = vsi->back;
-        struct i40e_hw *hw = &pf->hw;
-        int i, j, pf_q, ret = 0;
-        u32 tx_reg;
+        int i, pf_q, ret = 0;
 
         pf_q = vsi->base_queue;
         for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
+                i40e_control_tx_q(pf, pf_q, enable);
 
-                /* warn the TX unit of coming changes */
-                i40e_pre_tx_queue_cfg(&pf->hw, pf_q, enable);
-                if (!enable)
-                        usleep_range(10, 20);
-
-                for (j = 0; j < 50; j++) {
-                        tx_reg = rd32(hw, I40E_QTX_ENA(pf_q));
-                        if (((tx_reg >> I40E_QTX_ENA_QENA_REQ_SHIFT) & 1) ==
-                            ((tx_reg >> I40E_QTX_ENA_QENA_STAT_SHIFT) & 1))
-                                break;
-                        usleep_range(1000, 2000);
-                }
-                /* Skip if the queue is already in the requested state */
-                if (enable == !!(tx_reg & I40E_QTX_ENA_QENA_STAT_MASK))
-                        continue;
-
-                /* turn on/off the queue */
-                if (enable) {
-                        wr32(hw, I40E_QTX_HEAD(pf_q), 0);
-                        tx_reg |= I40E_QTX_ENA_QENA_REQ_MASK;
-                } else {
-                        tx_reg &= ~I40E_QTX_ENA_QENA_REQ_MASK;
-                }
-
-                wr32(hw, I40E_QTX_ENA(pf_q), tx_reg);
-                /* No waiting for the Tx queue to disable */
+                /* Don't wait to disable when port Tx is suspended */
                 if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
                         continue;
 
@@ -4035,6 +4055,43 @@ static int i40e_pf_rxq_wait(struct i40e_pf *pf, int pf_q, bool enable)
 }
 
 /**
+ * i40e_control_rx_q - Start or stop a particular Rx queue
+ * @pf: the PF structure
+ * @pf_q: the PF queue to configure
+ * @enable: start or stop the queue
+ *
+ * This function enables or disables a single queue. Note that any delay
+ * required after the operation is expected to be handled by the caller of
+ * this function.
+ **/
+static void i40e_control_rx_q(struct i40e_pf *pf, int pf_q, bool enable)
+{
+        struct i40e_hw *hw = &pf->hw;
+        u32 rx_reg;
+        int i;
+
+        for (i = 0; i < I40E_QTX_ENA_WAIT_COUNT; i++) {
+                rx_reg = rd32(hw, I40E_QRX_ENA(pf_q));
+                if (((rx_reg >> I40E_QRX_ENA_QENA_REQ_SHIFT) & 1) ==
+                    ((rx_reg >> I40E_QRX_ENA_QENA_STAT_SHIFT) & 1))
+                        break;
+                usleep_range(1000, 2000);
+        }
+
+        /* Skip if the queue is already in the requested state */
+        if (enable == !!(rx_reg & I40E_QRX_ENA_QENA_STAT_MASK))
+                return;
+
+        /* turn on/off the queue */
+        if (enable)
+                rx_reg |= I40E_QRX_ENA_QENA_REQ_MASK;
+        else
+                rx_reg &= ~I40E_QRX_ENA_QENA_REQ_MASK;
+
+        wr32(hw, I40E_QRX_ENA(pf_q), rx_reg);
+}
+
+/**
  * i40e_vsi_control_rx - Start or stop a VSI's rings
  * @vsi: the VSI being configured
  * @enable: start or stop the rings
@@ -4042,31 +4099,13 @@ static int i40e_pf_rxq_wait(struct i40e_pf *pf, int pf_q, bool enable)
 static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
 {
         struct i40e_pf *pf = vsi->back;
-        struct i40e_hw *hw = &pf->hw;
-        int i, j, pf_q, ret = 0;
-        u32 rx_reg;
+        int i, pf_q, ret = 0;
 
         pf_q = vsi->base_queue;
         for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
-                for (j = 0; j < 50; j++) {
-                        rx_reg = rd32(hw, I40E_QRX_ENA(pf_q));
-                        if (((rx_reg >> I40E_QRX_ENA_QENA_REQ_SHIFT) & 1) ==
-                            ((rx_reg >> I40E_QRX_ENA_QENA_STAT_SHIFT) & 1))
-                                break;
-                        usleep_range(1000, 2000);
-                }
+                i40e_control_rx_q(pf, pf_q, enable);
 
-                /* Skip if the queue is already in the requested state */
-                if (enable == !!(rx_reg & I40E_QRX_ENA_QENA_STAT_MASK))
-                        continue;
-
-                /* turn on/off the queue */
-                if (enable)
-                        rx_reg |= I40E_QRX_ENA_QENA_REQ_MASK;
-                else
-                        rx_reg &= ~I40E_QRX_ENA_QENA_REQ_MASK;
-                wr32(hw, I40E_QRX_ENA(pf_q), rx_reg);
-                /* No waiting for the Tx queue to disable */
+                /* Don't wait to disable when port Tx is suspended */
                 if (!enable && test_bit(__I40E_PORT_TX_SUSPENDED, &pf->state))
                         continue;