i40e: tighten up ring enable/disable flow

Change the do/while to a for loop, so we don't hit the delay each
time, even when the register is ready for action.
Don't bother to set or clear the QENA_STAT bit as it is
read-only.

Change-ID: Ie464718804dd79f6d726f291caa9b0c872b49978
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 3116861198f0e58bc636151f9daff9640cbe84a3..5259a602add0c336a392b48f763d06b550bf2770 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -3108,13 +3108,13 @@ static int i40e_vsi_control_tx(struct i40e_vsi *vsi, bool enable)
 
        pf_q = vsi->base_queue;
        for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
-               j = 1000;
-               do {
-                       usleep_range(1000, 2000);
+               for (j = 0; j < 50; j++) {
                        tx_reg = rd32(hw, I40E_QTX_ENA(pf_q));
-               } while (j-- && ((tx_reg >> I40E_QTX_ENA_QENA_REQ_SHIFT)
-                              ^ (tx_reg >> I40E_QTX_ENA_QENA_STAT_SHIFT)) & 1);
-
+                       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;
@@ -3124,8 +3124,7 @@ static int i40e_vsi_control_tx(struct i40e_vsi *vsi, bool enable)
                /* turn on/off the queue */
                if (enable) {
                        wr32(hw, I40E_QTX_HEAD(pf_q), 0);
-                       tx_reg |= I40E_QTX_ENA_QENA_REQ_MASK |
-                                 I40E_QTX_ENA_QENA_STAT_MASK;
+                       tx_reg |= I40E_QTX_ENA_QENA_REQ_MASK;
                } else {
                        tx_reg &= ~I40E_QTX_ENA_QENA_REQ_MASK;
                }
@@ -3172,12 +3171,13 @@ static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
 
        pf_q = vsi->base_queue;
        for (i = 0; i < vsi->num_queue_pairs; i++, pf_q++) {
-               j = 1000;
-               do {
-                       usleep_range(1000, 2000);
+               for (j = 0; j < 50; j++) {
                        rx_reg = rd32(hw, I40E_QRX_ENA(pf_q));
-               } while (j-- && ((rx_reg >> I40E_QRX_ENA_QENA_REQ_SHIFT)
-                              ^ (rx_reg >> I40E_QRX_ENA_QENA_STAT_SHIFT)) & 1);
+                       if (((rx_reg >> I40E_QRX_ENA_QENA_REQ_SHIFT) & 1) ==
+                           ((rx_reg >> I40E_QRX_ENA_QENA_STAT_SHIFT) & 1))
+                               break;
+                       usleep_range(1000, 2000);
+               }
 
                if (enable) {
                        /* is STAT set ? */
@@ -3191,11 +3191,9 @@ static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
 
                /* turn on/off the queue */
                if (enable)
-                       rx_reg |= I40E_QRX_ENA_QENA_REQ_MASK |
-                                 I40E_QRX_ENA_QENA_STAT_MASK;
+                       rx_reg |= I40E_QRX_ENA_QENA_REQ_MASK;
                else
-                       rx_reg &= ~(I40E_QRX_ENA_QENA_REQ_MASK |
-                                 I40E_QRX_ENA_QENA_STAT_MASK);
+                       rx_reg &= ~I40E_QRX_ENA_QENA_REQ_MASK;
                wr32(hw, I40E_QRX_ENA(pf_q), rx_reg);
 
                /* wait for the change to finish */