From: Anirudh Venkataramanan <anirudh.venkataramanan@xxxxxxxxx>
[ Upstream commit 3d6b640efcc1b07709b42dd2e9609401c6f88633 ]
This patch is a consolidation of multiple bug fixes for control queue
processing.
1) In ice_clean_adminq_subtask() remove unnecessary reads/writes to
registers. The bits PFINT_FW_CTL, PFINT_MBX_CTL and PFINT_SB_CTL
are not set when an interrupt arrives, which means that clearing them
again can be omitted.
2) Get an accurate value in "pending" by re-reading the control queue
head register from the hardware.
3) Fix a corner case involving lost control queue messages by checking
for new control messages (using ice_ctrlq_pending) before exiting the
cleanup routine.
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@xxxxxxxxx>
Tested-by: Tony Brelinski <tonyx.brelinski@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/ice/ice_controlq.c | 5 +++-
drivers/net/ethernet/intel/ice/ice_main.c | 26 ++++++++++++++++---
2 files changed, 26 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_controlq.c b/drivers/net/ethernet/intel/ice/ice_controlq.c
index c064416080e7..62be72fdc8f3 100644
--- a/drivers/net/ethernet/intel/ice/ice_controlq.c
+++ b/drivers/net/ethernet/intel/ice/ice_controlq.c
@@ -1065,8 +1065,11 @@ ice_clean_rq_elem(struct ice_hw *hw, struct ice_ctl_q_info *cq,
clean_rq_elem_out:
/* Set pending if needed, unlock and return */
- if (pending)
+ if (pending) {
+ /* re-read HW head to calculate actual pending messages */
+ ntu = (u16)(rd32(hw, cq->rq.head) & cq->rq.head_mask);
*pending = (u16)((ntc > ntu ? cq->rq.count : 0) + (ntu - ntc));
+ }
clean_rq_elem_err:
mutex_unlock(&cq->rq_lock);
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index 186e764a469a..46b35b78e8aa 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -916,6 +916,21 @@ static int __ice_clean_ctrlq(struct ice_pf *pf, enum ice_ctl_q q_type)
return pending && (i == ICE_DFLT_IRQ_WORK);
}
+/**
+ * ice_ctrlq_pending - check if there is a difference between ntc and ntu
+ * @hw: pointer to hardware info
+ * @cq: control queue information
+ *
+ * returns true if there are pending messages in a queue, false if there aren't
+ */
+static bool ice_ctrlq_pending(struct ice_hw *hw, struct ice_ctl_q_info *cq)
+{
+ u16 ntu;
+
+ ntu = (u16)(rd32(hw, cq->rq.head) & cq->rq.head_mask);
+ return cq->rq.next_to_clean != ntu;
+}
+
/**
* ice_clean_adminq_subtask - clean the AdminQ rings
* @pf: board private structure
@@ -923,7 +938,6 @@ static int __ice_clean_ctrlq(struct ice_pf *pf, enum ice_ctl_q q_type)
static void ice_clean_adminq_subtask(struct ice_pf *pf)
{
struct ice_hw *hw = &pf->hw;
- u32 val;
if (!test_bit(__ICE_ADMINQ_EVENT_PENDING, pf->state))
return;
@@ -933,9 +947,13 @@ static void ice_clean_adminq_subtask(struct ice_pf *pf)
clear_bit(__ICE_ADMINQ_EVENT_PENDING, pf->state);
- /* re-enable Admin queue interrupt causes */
- val = rd32(hw, PFINT_FW_CTL);
- wr32(hw, PFINT_FW_CTL, (val | PFINT_FW_CTL_CAUSE_ENA_M));
+ /* There might be a situation where new messages arrive to a control
+ * queue between processing the last message and clearing the
+ * EVENT_PENDING bit. So before exiting, check queue head again (using
+ * ice_ctrlq_pending) and process new messages if any.
+ */
+ if (ice_ctrlq_pending(hw, &hw->adminq))
+ __ice_clean_ctrlq(pf, ICE_CTL_Q_ADMIN);
ice_flush(hw);
}
--
2.17.1
