From 0364a0d0e7a124e7c821cc536a95f7ef421349cb Mon Sep 17 00:00:00 2001 From: Jesus Sanchez-Palencia Date: Tue, 3 Jul 2018 15:42:56 -0700 Subject: [PATCH] igb: Only change Tx arbitration when CBS is on Currently the data transmission arbitration algorithm - DataTranARB field on TQAVCTRL reg - is always set to CBS when the Tx mode is changed from legacy to 'Qav' mode. Make that configuration a bit more granular in preparation for the upcoming Launchtime enabling patches, since CBS and Launchtime can be enabled separately. That is achieved by moving the DataTranARB setup to igb_config_tx_modes() instead. Similarly, when disabling CBS we must check if it has been disabled for all queues, and clear the DataTranARB accordingly. Signed-off-by: Jesus Sanchez-Palencia Signed-off-by: David S. Miller --- drivers/net/ethernet/intel/igb/igb_main.c | 49 +++++++++++++++-------- 1 file changed, 33 insertions(+), 16 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 15f6b9c57ccf..8c90f1e51add 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -1654,6 +1654,18 @@ static void set_queue_mode(struct e1000_hw *hw, int queue, enum queue_mode mode) wr32(E1000_I210_TQAVCC(queue), val); } +static bool is_any_cbs_enabled(struct igb_adapter *adapter) +{ + int i; + + for (i = 0; i < adapter->num_tx_queues; i++) { + if (adapter->tx_ring[i]->cbs_enable) + return true; + } + + return false; +} + /** * igb_config_tx_modes - Configure "Qav Tx mode" features on igb * @adapter: pointer to adapter struct @@ -1668,7 +1680,7 @@ static void igb_config_tx_modes(struct igb_adapter *adapter, int queue) struct igb_ring *ring = adapter->tx_ring[queue]; struct net_device *netdev = adapter->netdev; struct e1000_hw *hw = &adapter->hw; - u32 tqavcc; + u32 tqavcc, tqavctrl; u16 value; WARN_ON(hw->mac.type != e1000_i210); @@ -1693,6 +1705,14 @@ static void igb_config_tx_modes(struct igb_adapter *adapter, int queue) set_tx_desc_fetch_prio(hw, queue, TX_QUEUE_PRIO_HIGH); set_queue_mode(hw, queue, QUEUE_MODE_STREAM_RESERVATION); + /* Always set data transfer arbitration to credit-based + * shaper algorithm on TQAVCTRL if CBS is enabled for any of + * the queues. + */ + tqavctrl = rd32(E1000_I210_TQAVCTRL); + tqavctrl |= E1000_TQAVCTRL_DATATRANARB; + wr32(E1000_I210_TQAVCTRL, tqavctrl); + /* According to i210 datasheet section 7.2.7.7, we should set * the 'idleSlope' field from TQAVCC register following the * equation: @@ -1770,6 +1790,16 @@ static void igb_config_tx_modes(struct igb_adapter *adapter, int queue) /* Set hiCredit to zero. */ wr32(E1000_I210_TQAVHC(queue), 0); + + /* If CBS is not enabled for any queues anymore, then return to + * the default state of Data Transmission Arbitration on + * TQAVCTRL. + */ + if (!is_any_cbs_enabled(adapter)) { + tqavctrl = rd32(E1000_I210_TQAVCTRL); + tqavctrl &= ~E1000_TQAVCTRL_DATATRANARB; + wr32(E1000_I210_TQAVCTRL, tqavctrl); + } } /* XXX: In i210 controller the sendSlope and loCredit parameters from @@ -1803,18 +1833,6 @@ static int igb_save_cbs_params(struct igb_adapter *adapter, int queue, return 0; } -static bool is_any_cbs_enabled(struct igb_adapter *adapter) -{ - int i; - - for (i = 0; i < adapter->num_tx_queues; i++) { - if (adapter->tx_ring[i]->cbs_enable) - return true; - } - - return false; -} - /** * igb_setup_tx_mode - Switch to/from Qav Tx mode when applicable * @adapter: pointer to adapter struct @@ -1838,11 +1856,10 @@ static void igb_setup_tx_mode(struct igb_adapter *adapter) int i, max_queue; /* Configure TQAVCTRL register: set transmit mode to 'Qav', - * set data fetch arbitration to 'round robin' and set data - * transfer arbitration to 'credit shaper algorithm. + * set data fetch arbitration to 'round robin'. */ val = rd32(E1000_I210_TQAVCTRL); - val |= E1000_TQAVCTRL_XMIT_MODE | E1000_TQAVCTRL_DATATRANARB; + val |= E1000_TQAVCTRL_XMIT_MODE; val &= ~E1000_TQAVCTRL_DATAFETCHARB; wr32(E1000_I210_TQAVCTRL, val); -- 2.30.2