[PATCH 6.1.y] ice: fix VF interrupts cleanup

From: Dawid Osuchowski <[email protected]>

[ Upstream commit fb096882095e5a8d6b5159e43793d4a38a0c5b1f ]

When a virtual function sends an IRQ map command, the PF will set up
interrupts according to that request. However, because these interrupts are
never reset, the next time Virtual Function initializes, the interrupts are
still enabled for a given VF, which leads to performance degradation in
certain cases due to interrupts being unexpectedly enabled and thus causing
interrupt floods.

Cc: [email protected]
Fixes: 1071a8358a28 ("ice: Implement virtchnl commands for AVF support")
Suggested-by: Vladimir Medvedkin <[email protected]>
Reviewed-by: Aleksandr Loktionov <[email protected]>
Signed-off-by: Dawid Osuchowski <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Tested-by: Patryk Holda <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
[ changed the file path for the `ice_vf_ena_rxq_interrupt` hunk from `ice/virt/queues.c` to `ice_virtchnl.c`, which predates the upstream directory split ]
Signed-off-by: Sasha Levin <[email protected]>
---
 drivers/net/ethernet/intel/ice/ice_vf_lib.c   | 27 +++++++++++++++++++
 .../ethernet/intel/ice/ice_vf_lib_private.h   |  1 +
 drivers/net/ethernet/intel/ice/ice_virtchnl.c | 21 +++++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib.c b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
index b1cc6f7a2e62b..258c365bdd7c6 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib.c
@@ -554,6 +554,30 @@ static void ice_notify_vf_reset(struct ice_vf *vf)
 			      NULL);
 }
 
+/**
+ * ice_reset_interrupts - clear all queue interrupt configuration for a VSI
+ * @vsi: the VSI whose interrupt registers should be cleared
+ *
+ * Zero the QINT_RQCTL and QINT_TQCTL registers for all allocated queues
+ * in the VSI. This clears the entire register including MSIX_INDX, ITR_INDX,
+ * CAUSE_ENA and NEXTQ fields, unlike ice_vf_dis_rxq_interrupt() which only
+ * clears the CAUSE_ENA bit.
+ */
+void ice_reset_interrupts(struct ice_vsi *vsi)
+{
+	struct ice_pf *pf = vsi->back;
+	struct ice_hw *hw = &pf->hw;
+	int i;
+
+	ice_for_each_alloc_rxq(vsi, i)
+		wr32(hw, QINT_RQCTL(vsi->rxq_map[i]), 0);
+
+	ice_for_each_alloc_txq(vsi, i)
+		wr32(hw, QINT_TQCTL(vsi->txq_map[i]), 0);
+
+	ice_flush(hw);
+}
+
 /**
  * ice_reset_vf - Reset a particular VF
  * @vf: pointer to the VF structure
@@ -623,6 +647,9 @@ int ice_reset_vf(struct ice_vf *vf, u32 flags)
 
 	ice_dis_vf_qs(vf);
 
+	/* cleanup interrupt registers */
+	ice_reset_interrupts(vsi);
+
 	/* Call Disable LAN Tx queue AQ whether or not queues are
 	 * enabled. This is needed for successful completion of VFR.
 	 */
diff --git a/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h b/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
index 15887e772c76e..ea1770730e2ac 100644
--- a/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
+++ b/drivers/net/ethernet/intel/ice/ice_vf_lib_private.h
@@ -24,6 +24,7 @@
 #endif
 
 void ice_dis_vf_qs(struct ice_vf *vf);
+void ice_reset_interrupts(struct ice_vsi *vsi);
 int ice_check_vf_init(struct ice_vf *vf);
 struct ice_port_info *ice_vf_get_port_info(struct ice_vf *vf);
 int ice_vsi_apply_spoofchk(struct ice_vsi *vsi, bool enable);
diff --git a/drivers/net/ethernet/intel/ice/ice_virtchnl.c b/drivers/net/ethernet/intel/ice/ice_virtchnl.c
index 7cc04e7a9eef0..807a37c39f9a5 100644
--- a/drivers/net/ethernet/intel/ice/ice_virtchnl.c
+++ b/drivers/net/ethernet/intel/ice/ice_virtchnl.c
@@ -1209,6 +1209,24 @@ static void ice_vf_ena_rxq_interrupt(struct ice_vsi *vsi, u32 q_idx)
 	wr32(hw, QINT_RQCTL(pfq), reg | QINT_RQCTL_CAUSE_ENA_M);
 }
 
+/**
+ * ice_vf_dis_rxq_interrupt - disable Rx queue interrupt via QINT_RQCTL
+ * @vsi: VSI of the VF to configure
+ * @q_idx: VF queue index used to determine the queue in the PF's space
+ */
+static void ice_vf_dis_rxq_interrupt(struct ice_vsi *vsi, u32 q_idx)
+{
+	struct ice_hw *hw = &vsi->back->hw;
+	u32 pfq = vsi->rxq_map[q_idx];
+	u32 reg;
+
+	reg = rd32(hw, QINT_RQCTL(pfq));
+	reg &= ~QINT_RQCTL_CAUSE_ENA_M;
+	wr32(hw, QINT_RQCTL(pfq), reg);
+
+	ice_flush(hw);
+}
+
 /**
  * ice_vc_ena_qs_msg
  * @vf: pointer to the VF info
@@ -1402,6 +1420,8 @@ static int ice_vc_dis_qs_msg(struct ice_vf *vf, u8 *msg)
 			goto error_param;
 		}
 
+		for_each_set_bit(vf_q_id, &q_map, ICE_MAX_RSS_QS_PER_VF)
+			ice_vf_dis_rxq_interrupt(vsi, vf_q_id);
 		bitmap_zero(vf->rxq_ena, ICE_MAX_RSS_QS_PER_VF);
 	} else if (q_map) {
 		for_each_set_bit(vf_q_id, &q_map, ICE_MAX_RSS_QS_PER_VF) {
@@ -1422,6 +1442,7 @@ static int ice_vc_dis_qs_msg(struct ice_vf *vf, u8 *msg)
 				goto error_param;
 			}
 
+			ice_vf_dis_rxq_interrupt(vsi, vf_q_id);
 			/* Clear enabled queues flag */
 			clear_bit(vf_q_id, vf->rxq_ena);
 		}
-- 
2.53.0