ice: Auxbus devices & driver for E822 TS

There is a problem in HW in E822-based devices leading to race
condition.
It might happen that, in order:
- PF0 (which owns the PHC) requests few timestamps,
- PF1 requests a timestamp,
- interrupt is being triggered and both PF0 and PF1 threads are woken
up,
- PF0 got one timestamp, still waiting for others so not going to sleep,
- PF1 gets it's timestamp, process it and go to sleep,
- PF1 requests a timestamp again,
- just before PF0 goes to sleep timestamp of PF1 appear,
- PF0 finishes all it's timestamps and go to sleep (PF1 also sleeping).
That leaves PF1 timestamp memory not read, which lead to blocking the
next interrupt from arriving.

Fix it by adding auxiliary devices and only one driver to handle all the
timestamps for all PF's by PHC owner. In the past each PF requested it's
own timestamps and process it from the start till the end which causes
problem described above. Currently each PF requests the timestamps as
before, but the actual reading of the completed timestamps is being done
by the PTP auxiliary driver, which is registered by the PF which owns PHC.

Additionally, the newly introduced auxiliary driver/devices for PTP clock
owner will be used for other features in all products (including E810).

Signed-off-by: Jacob Keller <[email protected]>
Signed-off-by: Karol Kolacinski <[email protected]>
Signed-off-by: Michal Michalik <[email protected]>
Tested-by: Pucha Himasekhar Reddy <[email protected]> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <[email protected]>

Author: mmichaliINTC

drivers/net/ethernet/intel/ice/ice.h

@@ -673,6 +673,18 @@ static inline bool ice_vector_ch_enabled(struct ice_q_vector *qv)
 	return !!qv->ch; /* Enable it to run with TC */
 }
 
+/**
+ * ice_ptp_pf_handles_tx_interrupt - Check if PF handles Tx interrupt
+ * @pf: Board private structure
+ *
+ * Return true if this PF should respond to the Tx timestamp interrupt
+ * indication in the miscellaneous OICR interrupt handler.
+ */
+static inline bool ice_ptp_pf_handles_tx_interrupt(struct ice_pf *pf)
+{
+	return pf->ptp.tx_interrupt_mode != ICE_PTP_TX_INTERRUPT_NONE;
+}
+
 /**
  * ice_irq_dynamic_ena - Enable default interrupt generation settings
  * @hw: pointer to HW struct

drivers/net/ethernet/intel/ice/ice_hw_autogen.h

@@ -231,6 +231,7 @@
 #define PFINT_SB_CTL				0x0016B600
 #define PFINT_SB_CTL_MSIX_INDX_M		ICE_M(0x7FF, 0)
 #define PFINT_SB_CTL_CAUSE_ENA_M		BIT(30)
+#define PFINT_TSYN_MSK				0x0016C980
 #define QINT_RQCTL(_QRX)			(0x00150000 + ((_QRX) * 4))
 #define QINT_RQCTL_MSIX_INDX_S			0
 #define QINT_RQCTL_MSIX_INDX_M			ICE_M(0x7FF, 0)

drivers/net/ethernet/intel/ice/ice_main.c

@@ -3149,7 +3149,7 @@ static irqreturn_t ice_misc_intr(int __always_unused irq, void *data)
 
 	if (oicr & PFINT_OICR_TSYN_TX_M) {
 		ena_mask &= ~PFINT_OICR_TSYN_TX_M;
-		if (!hw->reset_ongoing)
+		if (!hw->reset_ongoing && ice_ptp_pf_handles_tx_interrupt(pf))
 			set_bit(ICE_MISC_THREAD_TX_TSTAMP, pf->misc_thread);
 	}
 
@@ -7375,8 +7375,13 @@ static void ice_rebuild(struct ice_pf *pf, enum ice_reset_req reset_type)
 	}
 
 	/* configure PTP timestamping after VSI rebuild */
-	if (test_bit(ICE_FLAG_PTP_SUPPORTED, pf->flags))
-		ice_ptp_cfg_timestamp(pf, false);
+	if (test_bit(ICE_FLAG_PTP_SUPPORTED, pf->flags)) {
+		if (pf->ptp.tx_interrupt_mode == ICE_PTP_TX_INTERRUPT_SELF)
+			ice_ptp_cfg_timestamp(pf, false);
+		else if (pf->ptp.tx_interrupt_mode == ICE_PTP_TX_INTERRUPT_ALL)
+			/* for E82x PHC owner always need to have interrupts */
+			ice_ptp_cfg_timestamp(pf, true);
+	}
 
 	err = ice_vsi_rebuild_by_type(pf, ICE_VSI_SWITCHDEV_CTRL);
 	if (err) {