Merge branch 'add-perout-configuration-support-in-iep-driver'

Meghana Malladi says:

====================
Add perout configuration support in IEP driver

IEP driver supported both perout and pps signal generation
but perout feature is faulty with half-cooked support
due to some missing configuration. Hence perout feature is
removed as a bug fix. This patch series adds back this feature
which configures perout signal based on the arguments passed
by the perout request.

This patch series is continuation to the bug fix:
https://lore.kernel.org/[email protected]
as suggested by Jakub Kicinski and Jacob Keller:
https://lore.kernel.org/[email protected]

v3: https://lore.kernel.org/[email protected]
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

drivers/net/ethernet/ti/icssg/icss_iep.c

@@ -406,9 +406,25 @@ static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
 static int icss_iep_perout_enable_hw(struct icss_iep *iep,
 				     struct ptp_perout_request *req, int on)
 {
+	struct timespec64 ts;
+	u64 ns_start;
+	u64 ns_width;
 	int ret;
 	u64 cmp;
 
+	/* Calculate width of the signal for PPS/PEROUT handling */
+	ts.tv_sec = req->on.sec;
+	ts.tv_nsec = req->on.nsec;
+	ns_width = timespec64_to_ns(&ts);
+
+	if (req->flags & PTP_PEROUT_PHASE) {
+		ts.tv_sec = req->phase.sec;
+		ts.tv_nsec = req->phase.nsec;
+		ns_start = timespec64_to_ns(&ts);
+	} else {
+		ns_start = 0;
+	}
+
 	if (iep->ops && iep->ops->perout_enable) {
 		ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
 		if (ret)
@@ -419,10 +435,12 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
-			/* Configure SYNC, 1ms pulse width */
-			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, 1000000);
+			/* Configure SYNC, based on req on width */
+			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
+				     div_u64(ns_width, iep->def_inc));
 			regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
-			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
+			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
+				     div_u64(ns_start, iep->def_inc));
 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
 			/* Enable CMP 1 */
 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
@@ -447,6 +465,10 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
 				   + req->period.nsec;
 			icss_iep_update_to_next_boundary(iep, start_ns);
 
+			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
+				     div_u64(ns_width, iep->def_inc));
+			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
+				     div_u64(ns_start, iep->def_inc));
 			/* Enable Sync in single shot mode  */
 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
 				     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
@@ -474,7 +496,37 @@ static int icss_iep_perout_enable_hw(struct icss_iep *iep,
 static int icss_iep_perout_enable(struct icss_iep *iep,
 				  struct ptp_perout_request *req, int on)
 {
-	return -EOPNOTSUPP;
+	int ret = 0;
+
+	/* Reject requests with unsupported flags */
+	if (req->flags & ~(PTP_PEROUT_DUTY_CYCLE |
+			  PTP_PEROUT_PHASE))
+		return -EOPNOTSUPP;
+
+	mutex_lock(&iep->ptp_clk_mutex);
+
+	if (iep->pps_enabled) {
+		ret = -EBUSY;
+		goto exit;
+	}
+
+	if (iep->perout_enabled == !!on)
+		goto exit;
+
+	/* Set default "on" time (1ms) for the signal if not passed by the app */
+	if (!(req->flags & PTP_PEROUT_DUTY_CYCLE)) {
+		req->on.sec = 0;
+		req->on.nsec = NSEC_PER_MSEC;
+	}
+
+	ret = icss_iep_perout_enable_hw(iep, req, on);
+	if (!ret)
+		iep->perout_enabled = !!on;
+
+exit:
+	mutex_unlock(&iep->ptp_clk_mutex);
+
+	return ret;
 }
 
 static void icss_iep_cap_cmp_work(struct work_struct *work)
@@ -549,10 +601,13 @@ static int icss_iep_pps_enable(struct icss_iep *iep, int on)
 	if (on) {
 		ns = icss_iep_gettime(iep, NULL);
 		ts = ns_to_timespec64(ns);
+		rq.perout.flags = 0;
 		rq.perout.period.sec = 1;
 		rq.perout.period.nsec = 0;
 		rq.perout.start.sec = ts.tv_sec + 2;
 		rq.perout.start.nsec = 0;
+		rq.perout.on.sec = 0;
+		rq.perout.on.nsec = NSEC_PER_MSEC;
 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
 	} else {
 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);