ice: handle extts in the miscellaneous interrupt thread

The ice_ptp_extts_work() and ice_ptp_periodic_work() functions are both
scheduled on the same kthread worker, pf.ptp.kworker. The
ice_ptp_periodic_work() function sends to the firmware to interact with the
PHY, and must block to wait for responses.

This can cause delay in responding to the PFINT_OICR_TSYN_EVNT interrupt
cause, ultimately resulting in disruption to processing an input signal of
the frequency is high enough. In our testing, even 100 Hz signals get
disrupted.

Fix this by instead processing the signal inside the miscellaneous
interrupt thread prior to handling Tx timestamps.

Use atomic bits in a new pf->misc_thread bitmap in order to safely
communicate which tasks require processing within the
ice_misc_intr_thread_fn(). This ensures the communication of desired tasks
from the ice_misc_intr() are correctly processed without racing even in the
event that the interrupt triggers again before the thread function exits.

Fixes: 172db5f91d5f ("ice: add support for auxiliary input/output pins")
Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Arpana Arland <arpanax.arland@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice.h b/drivers/net/ethernet/intel/ice/ice.h
index b4bca1d964a9..4ba3d99439a0 100644
--- a/drivers/net/ethernet/intel/ice/ice.h
+++ b/drivers/net/ethernet/intel/ice/ice.h
@@ -508,6 +508,12 @@ enum ice_pf_flags {
 	ICE_PF_FLAGS_NBITS		/* must be last */
 };
 
+enum ice_misc_thread_tasks {
+	ICE_MISC_THREAD_EXTTS_EVENT,
+	ICE_MISC_THREAD_TX_TSTAMP,
+	ICE_MISC_THREAD_NBITS		/* must be last */
+};
+
 struct ice_switchdev_info {
 	struct ice_vsi *control_vsi;
 	struct ice_vsi *uplink_vsi;
@@ -550,6 +556,7 @@ struct ice_pf {
 	DECLARE_BITMAP(features, ICE_F_MAX);
 	DECLARE_BITMAP(state, ICE_STATE_NBITS);
 	DECLARE_BITMAP(flags, ICE_PF_FLAGS_NBITS);
+	DECLARE_BITMAP(misc_thread, ICE_MISC_THREAD_NBITS);
 	unsigned long *avail_txqs;	/* bitmap to track PF Tx queue usage */
 	unsigned long *avail_rxqs;	/* bitmap to track PF Rx queue usage */
 	unsigned long serv_tmr_period;