igc: enable auxiliary PHC functions for the i225

The i225 device offers a number of special PTP Hardware Clock features on
the Software Defined Pins (SDPs) - much like i210, which is used as
inspiration for this patch. It enables two possible functions, namely
time stamping external events and periodic output signals.

The assignment of PHC functions to the four SDP can be freely chosen by
the user.

For the external events time stamping, when the SDP (configured as input
by user) level changes, an interrupt is generated and the kernel
Precision Time Protocol (PTP) is informed.

For the periodic output signals, the i225 is configured to generate them
(so the SDP level will change periodically) and the driver also has to
keep updating the time of the next level change. However, this work is
not necessary for some frequencies as the i225 takes care of them
(namely, anything with a half-cycle of 500ms, 250ms, 125ms or < 70ms).

While i225 allows up to four timers to be used to source the time used
on the external events or output signals, this patch uses only one of
those timers. Main reason is to keep it simple, as it's not clear how
these extra timers would be exposed to users. Note that currently a NIC
can expose a single PTP device.

Signed-off-by: Ederson de Souza <ederson.desouza@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 268 insertions, 1 deletions

diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index 8d6fbf609761..69617d2c1be2 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c
@@ -120,6 +120,124 @@ static int igc_ptp_settime_i225(struct ptp_clock_info *ptp,
 	return 0;
 }
 
+static void igc_pin_direction(int pin, int input, u32 *ctrl, u32 *ctrl_ext)
+{
+	u32 *ptr = pin < 2 ? ctrl : ctrl_ext;
+	static const u32 mask[IGC_N_SDP] = {
+		IGC_CTRL_SDP0_DIR,
+		IGC_CTRL_SDP1_DIR,
+		IGC_CTRL_EXT_SDP2_DIR,
+		IGC_CTRL_EXT_SDP3_DIR,
+	};
+
+	if (input)
+		*ptr &= ~mask[pin];
+	else
+		*ptr |= mask[pin];
+}
+
+static void igc_pin_perout(struct igc_adapter *igc, int chan, int pin, int freq)
+{
+	static const u32 igc_aux0_sel_sdp[IGC_N_SDP] = {
+		IGC_AUX0_SEL_SDP0, IGC_AUX0_SEL_SDP1, IGC_AUX0_SEL_SDP2, IGC_AUX0_SEL_SDP3,
+	};
+	static const u32 igc_aux1_sel_sdp[IGC_N_SDP] = {
+		IGC_AUX1_SEL_SDP0, IGC_AUX1_SEL_SDP1, IGC_AUX1_SEL_SDP2, IGC_AUX1_SEL_SDP3,
+	};
+	static const u32 igc_ts_sdp_en[IGC_N_SDP] = {
+		IGC_TS_SDP0_EN, IGC_TS_SDP1_EN, IGC_TS_SDP2_EN, IGC_TS_SDP3_EN,
+	};
+	static const u32 igc_ts_sdp_sel_tt0[IGC_N_SDP] = {
+		IGC_TS_SDP0_SEL_TT0, IGC_TS_SDP1_SEL_TT0,
+		IGC_TS_SDP2_SEL_TT0, IGC_TS_SDP3_SEL_TT0,
+	};
+	static const u32 igc_ts_sdp_sel_tt1[IGC_N_SDP] = {
+		IGC_TS_SDP0_SEL_TT1, IGC_TS_SDP1_SEL_TT1,
+		IGC_TS_SDP2_SEL_TT1, IGC_TS_SDP3_SEL_TT1,
+	};
+	static const u32 igc_ts_sdp_sel_fc0[IGC_N_SDP] = {
+		IGC_TS_SDP0_SEL_FC0, IGC_TS_SDP1_SEL_FC0,
+		IGC_TS_SDP2_SEL_FC0, IGC_TS_SDP3_SEL_FC0,
+	};
+	static const u32 igc_ts_sdp_sel_fc1[IGC_N_SDP] = {
+		IGC_TS_SDP0_SEL_FC1, IGC_TS_SDP1_SEL_FC1,
+		IGC_TS_SDP2_SEL_FC1, IGC_TS_SDP3_SEL_FC1,
+	};
+	static const u32 igc_ts_sdp_sel_clr[IGC_N_SDP] = {
+		IGC_TS_SDP0_SEL_FC1, IGC_TS_SDP1_SEL_FC1,
+		IGC_TS_SDP2_SEL_FC1, IGC_TS_SDP3_SEL_FC1,
+	};
+	struct igc_hw *hw = &igc->hw;
+	u32 ctrl, ctrl_ext, tssdp = 0;
+
+	ctrl = rd32(IGC_CTRL);
+	ctrl_ext = rd32(IGC_CTRL_EXT);
+	tssdp = rd32(IGC_TSSDP);
+
+	igc_pin_direction(pin, 0, &ctrl, &ctrl_ext);
+
+	/* Make sure this pin is not enabled as an input. */
+	if ((tssdp & IGC_AUX0_SEL_SDP3) == igc_aux0_sel_sdp[pin])
+		tssdp &= ~IGC_AUX0_TS_SDP_EN;
+
+	if ((tssdp & IGC_AUX1_SEL_SDP3) == igc_aux1_sel_sdp[pin])
+		tssdp &= ~IGC_AUX1_TS_SDP_EN;
+
+	tssdp &= ~igc_ts_sdp_sel_clr[pin];
+	if (freq) {
+		if (chan == 1)
+			tssdp |= igc_ts_sdp_sel_fc1[pin];
+		else
+			tssdp |= igc_ts_sdp_sel_fc0[pin];
+	} else {
+		if (chan == 1)
+			tssdp |= igc_ts_sdp_sel_tt1[pin];
+		else
+			tssdp |= igc_ts_sdp_sel_tt0[pin];
+	}
+	tssdp |= igc_ts_sdp_en[pin];
+
+	wr32(IGC_TSSDP, tssdp);
+	wr32(IGC_CTRL, ctrl);
+	wr32(IGC_CTRL_EXT, ctrl_ext);
+}
+
+static void igc_pin_extts(struct igc_adapter *igc, int chan, int pin)
+{
+	static const u32 igc_aux0_sel_sdp[IGC_N_SDP] = {
+		IGC_AUX0_SEL_SDP0, IGC_AUX0_SEL_SDP1, IGC_AUX0_SEL_SDP2, IGC_AUX0_SEL_SDP3,
+	};
+	static const u32 igc_aux1_sel_sdp[IGC_N_SDP] = {
+		IGC_AUX1_SEL_SDP0, IGC_AUX1_SEL_SDP1, IGC_AUX1_SEL_SDP2, IGC_AUX1_SEL_SDP3,
+	};
+	static const u32 igc_ts_sdp_en[IGC_N_SDP] = {
+		IGC_TS_SDP0_EN, IGC_TS_SDP1_EN, IGC_TS_SDP2_EN, IGC_TS_SDP3_EN,
+	};
+	struct igc_hw *hw = &igc->hw;
+	u32 ctrl, ctrl_ext, tssdp = 0;
+
+	ctrl = rd32(IGC_CTRL);
+	ctrl_ext = rd32(IGC_CTRL_EXT);
+	tssdp = rd32(IGC_TSSDP);
+
+	igc_pin_direction(pin, 1, &ctrl, &ctrl_ext);
+
+	/* Make sure this pin is not enabled as an output. */
+	tssdp &= ~igc_ts_sdp_en[pin];
+
+	if (chan == 1) {
+		tssdp &= ~IGC_AUX1_SEL_SDP3;
+		tssdp |= igc_aux1_sel_sdp[pin] | IGC_AUX1_TS_SDP_EN;
+	} else {
+		tssdp &= ~IGC_AUX0_SEL_SDP3;
+		tssdp |= igc_aux0_sel_sdp[pin] | IGC_AUX0_TS_SDP_EN;
+	}
+
+	wr32(IGC_TSSDP, tssdp);
+	wr32(IGC_CTRL, ctrl);
+	wr32(IGC_CTRL_EXT, ctrl_ext);
+}
+
 static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 				       struct ptp_clock_request *rq, int on)
 {
@@ -127,9 +245,131 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 		container_of(ptp, struct igc_adapter, ptp_caps);
 	struct igc_hw *hw = &igc->hw;
 	unsigned long flags;
-	u32 tsim;
+	struct timespec64 ts;
+	int use_freq = 0, pin = -1;
+	u32 tsim, tsauxc, tsauxc_mask, tsim_mask, trgttiml, trgttimh, freqout;
+	s64 ns;
 
 	switch (rq->type) {
+	case PTP_CLK_REQ_EXTTS:
+		/* Reject requests with unsupported flags */
+		if (rq->extts.flags & ~(PTP_ENABLE_FEATURE |
+					PTP_RISING_EDGE |
+					PTP_FALLING_EDGE |
+					PTP_STRICT_FLAGS))
+			return -EOPNOTSUPP;
+
+		/* Reject requests failing to enable both edges. */
+		if ((rq->extts.flags & PTP_STRICT_FLAGS) &&
+		    (rq->extts.flags & PTP_ENABLE_FEATURE) &&
+		    (rq->extts.flags & PTP_EXTTS_EDGES) != PTP_EXTTS_EDGES)
+			return -EOPNOTSUPP;
+
+		if (on) {
+			pin = ptp_find_pin(igc->ptp_clock, PTP_PF_EXTTS,
+					   rq->extts.index);
+			if (pin < 0)
+				return -EBUSY;
+		}
+		if (rq->extts.index == 1) {
+			tsauxc_mask = IGC_TSAUXC_EN_TS1;
+			tsim_mask = IGC_TSICR_AUTT1;
+		} else {
+			tsauxc_mask = IGC_TSAUXC_EN_TS0;
+			tsim_mask = IGC_TSICR_AUTT0;
+		}
+		spin_lock_irqsave(&igc->tmreg_lock, flags);
+		tsauxc = rd32(IGC_TSAUXC);
+		tsim = rd32(IGC_TSIM);
+		if (on) {
+			igc_pin_extts(igc, rq->extts.index, pin);
+			tsauxc |= tsauxc_mask;
+			tsim |= tsim_mask;
+		} else {
+			tsauxc &= ~tsauxc_mask;
+			tsim &= ~tsim_mask;
+		}
+		wr32(IGC_TSAUXC, tsauxc);
+		wr32(IGC_TSIM, tsim);
+		spin_unlock_irqrestore(&igc->tmreg_lock, flags);
+		return 0;
+
+	case PTP_CLK_REQ_PEROUT:
+		/* Reject requests with unsupported flags */
+		if (rq->perout.flags)
+			return -EOPNOTSUPP;
+
+		if (on) {
+			pin = ptp_find_pin(igc->ptp_clock, PTP_PF_PEROUT,
+					   rq->perout.index);
+			if (pin < 0)
+				return -EBUSY;
+		}
+		ts.tv_sec = rq->perout.period.sec;
+		ts.tv_nsec = rq->perout.period.nsec;
+		ns = timespec64_to_ns(&ts);
+		ns = ns >> 1;
+		if (on && (ns <= 70000000LL || ns == 125000000LL ||
+			   ns == 250000000LL || ns == 500000000LL)) {
+			if (ns < 8LL)
+				return -EINVAL;
+			use_freq = 1;
+		}
+		ts = ns_to_timespec64(ns);
+		if (rq->perout.index == 1) {
+			if (use_freq) {
+				tsauxc_mask = IGC_TSAUXC_EN_CLK1;
+				tsim_mask = 0;
+			} else {
+				tsauxc_mask = IGC_TSAUXC_EN_TT1;
+				tsim_mask = IGC_TSICR_TT1;
+			}
+			trgttiml = IGC_TRGTTIML1;
+			trgttimh = IGC_TRGTTIMH1;
+			freqout = IGC_FREQOUT1;
+		} else {
+			if (use_freq) {
+				tsauxc_mask = IGC_TSAUXC_EN_CLK0;
+				tsim_mask = 0;
+			} else {
+				tsauxc_mask = IGC_TSAUXC_EN_TT0;
+				tsim_mask = IGC_TSICR_TT0;
+			}
+			trgttiml = IGC_TRGTTIML0;
+			trgttimh = IGC_TRGTTIMH0;
+			freqout = IGC_FREQOUT0;
+		}
+		spin_lock_irqsave(&igc->tmreg_lock, flags);
+		tsauxc = rd32(IGC_TSAUXC);
+		tsim = rd32(IGC_TSIM);
+		if (rq->perout.index == 1) {
+			tsauxc &= ~(IGC_TSAUXC_EN_TT1 | IGC_TSAUXC_EN_CLK1);
+			tsim &= ~IGC_TSICR_TT1;
+		} else {
+			tsauxc &= ~(IGC_TSAUXC_EN_TT0 | IGC_TSAUXC_EN_CLK0);
+			tsim &= ~IGC_TSICR_TT0;
+		}
+		if (on) {
+			int i = rq->perout.index;
+
+			igc_pin_perout(igc, i, pin, use_freq);
+			igc->perout[i].start.tv_sec = rq->perout.start.sec;
+			igc->perout[i].start.tv_nsec = rq->perout.start.nsec;
+			igc->perout[i].period.tv_sec = ts.tv_sec;
+			igc->perout[i].period.tv_nsec = ts.tv_nsec;
+			wr32(trgttimh, rq->perout.start.sec);
+			/* For now, always select timer 0 as source. */
+			wr32(trgttiml, rq->perout.start.nsec | IGC_TT_IO_TIMER_SEL_SYSTIM0);
+			if (use_freq)
+				wr32(freqout, ns);
+			tsauxc |= tsauxc_mask;
+			tsim |= tsim_mask;
+		}
+		wr32(IGC_TSAUXC, tsauxc);
+		wr32(IGC_TSIM, tsim);
+		spin_unlock_irqrestore(&igc->tmreg_lock, flags);
+		return 0;
+
 	case PTP_CLK_REQ_PPS:
 		spin_lock_irqsave(&igc->tmreg_lock, flags);
 		tsim = rd32(IGC_TSIM);
@@ -149,6 +389,20 @@ static int igc_ptp_feature_enable_i225(struct ptp_clock_info *ptp,
 	return -EOPNOTSUPP;
 }
 
+static int igc_ptp_verify_pin(struct ptp_clock_info *ptp, unsigned int pin,
+			      enum ptp_pin_function func, unsigned int chan)
+{
+	switch (func) {
+	case PTP_PF_NONE:
+	case PTP_PF_EXTTS:
+	case PTP_PF_PEROUT:
+		break;
+	case PTP_PF_PHYSYNC:
+		return -1;
+	}
+	return 0;
+}
+
 /**
  * igc_ptp_systim_to_hwtstamp - convert system time value to HW timestamp
  * @adapter: board private structure
@@ -509,9 +763,17 @@ void igc_ptp_init(struct igc_adapter *adapter)
 {
 	struct net_device *netdev = adapter->netdev;
 	struct igc_hw *hw = &adapter->hw;
+	int i;
 
 	switch (hw->mac.type) {
 	case igc_i225:
+		for (i = 0; i < IGC_N_SDP; i++) {
+			struct ptp_pin_desc *ppd = &adapter->sdp_config[i];
+
+			snprintf(ppd->name, sizeof(ppd->name), "SDP%d", i);
+			ppd->index = i;
+			ppd->func = PTP_PF_NONE;
+		}
 		snprintf(adapter->ptp_caps.name, 16, "%pm", netdev->dev_addr);
 		adapter->ptp_caps.owner = THIS_MODULE;
 		adapter->ptp_caps.max_adj = 62499999;
@@ -521,6 +783,11 @@ void igc_ptp_init(struct igc_adapter *adapter)
 		adapter->ptp_caps.settime64 = igc_ptp_settime_i225;
 		adapter->ptp_caps.enable = igc_ptp_feature_enable_i225;
 		adapter->ptp_caps.pps = 1;
+		adapter->ptp_caps.pin_config = adapter->sdp_config;
+		adapter->ptp_caps.n_ext_ts = IGC_N_EXTTS;
+		adapter->ptp_caps.n_per_out = IGC_N_PEROUT;
+		adapter->ptp_caps.n_pins = IGC_N_SDP;
+		adapter->ptp_caps.verify = igc_ptp_verify_pin;
 		break;
 	default:
 		adapter->ptp_clock = NULL;