From: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
Date: Tue, 3 Jul 2018 15:42:56 -0700
Subject: igb: Only change Tx arbitration when CBS is on
Patch-mainline: v4.19-rc1
Git-commit: 0364a0d0e7a124e7c821cc536a95f7ef421349cb
References: bsc#1117495
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 <jesus.sanchez-palencia@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/intel/igb/igb_main.c | 49 ++++++++++++++++++++----------
1 file changed, 33 insertions(+), 16 deletions(-)
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -1674,6 +1674,18 @@ static void set_queue_mode(struct e1000_
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
@@ -1688,7 +1700,7 @@ static void igb_config_tx_modes(struct i
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);
@@ -1713,6 +1725,14 @@ static void igb_config_tx_modes(struct i
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:
@@ -1790,6 +1810,16 @@ static void igb_config_tx_modes(struct i
/* 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
@@ -1823,18 +1853,6 @@ static int igb_save_cbs_params(struct ig
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
@@ -1858,11 +1876,10 @@ static void igb_setup_tx_mode(struct igb
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);