1 files changed, 173 insertions, 60 deletions

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 85a55b4ff8c0..0c0d48e5bea4 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -31,10 +31,8 @@
 
 #include "cpts.h"
 
-#ifdef CONFIG_TI_CPTS
-
-#define cpts_read32(c, r)	__raw_readl(&c->reg->r)
-#define cpts_write32(c, v, r)	__raw_writel(v, &c->reg->r)
+#define cpts_read32(c, r)	readl_relaxed(&c->reg->r)
+#define cpts_write32(c, v, r)	writel_relaxed(v, &c->reg->r)
 
 static int event_expired(struct cpts_event *event)
 {
@@ -59,6 +57,26 @@ static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low)
 	return -1;
 }
 
+static int cpts_purge_events(struct cpts *cpts)
+{
+	struct list_head *this, *next;
+	struct cpts_event *event;
+	int removed = 0;
+
+	list_for_each_safe(this, next, &cpts->events) {
+		event = list_entry(this, struct cpts_event, list);
+		if (event_expired(event)) {
+			list_del_init(&event->list);
+			list_add(&event->list, &cpts->pool);
+			++removed;
+		}
+	}
+
+	if (removed)
+		pr_debug("cpts: event pool cleaned up %d\n", removed);
+	return removed ? 0 : -1;
+}
+
 /*
  * Returns zero if matching event type was found.
  */
@@ -71,10 +89,12 @@ static int cpts_fifo_read(struct cpts *cpts, int match)
 	for (i = 0; i < CPTS_FIFO_DEPTH; i++) {
 		if (cpts_fifo_pop(cpts, &hi, &lo))
 			break;
-		if (list_empty(&cpts->pool)) {
-			pr_err("cpts: event pool is empty\n");
+
+		if (list_empty(&cpts->pool) && cpts_purge_events(cpts)) {
+			pr_err("cpts: event pool empty\n");
 			return -1;
 		}
+
 		event = list_first_entry(&cpts->pool, struct cpts_event, list);
 		event->tmo = jiffies + 2;
 		event->high = hi;
@@ -223,27 +243,9 @@ static void cpts_overflow_check(struct work_struct *work)
 	struct timespec64 ts;
 	struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
 
-	cpts_write32(cpts, CPTS_EN, control);
-	cpts_write32(cpts, TS_PEND_EN, int_enable);
 	cpts_ptp_gettime(&cpts->info, &ts);
 	pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
-	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
-}
-
-static void cpts_clk_init(struct device *dev, struct cpts *cpts)
-{
-	cpts->refclk = devm_clk_get(dev, "cpts");
-	if (IS_ERR(cpts->refclk)) {
-		dev_err(dev, "Failed to get cpts refclk\n");
-		cpts->refclk = NULL;
-		return;
-	}
-	clk_prepare_enable(cpts->refclk);
-}
-
-static void cpts_clk_release(struct cpts *cpts)
-{
-	clk_disable(cpts->refclk);
+	schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
 }
 
 static int cpts_match(struct sk_buff *skb, unsigned int ptp_class,
@@ -334,6 +336,7 @@ void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	memset(ssh, 0, sizeof(*ssh));
 	ssh->hwtstamp = ns_to_ktime(ns);
 }
+EXPORT_SYMBOL_GPL(cpts_rx_timestamp);
 
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
@@ -349,60 +352,170 @@ void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 	ssh.hwtstamp = ns_to_ktime(ns);
 	skb_tstamp_tx(skb, &ssh);
 }
+EXPORT_SYMBOL_GPL(cpts_tx_timestamp);
 
-#endif /*CONFIG_TI_CPTS*/
-
-int cpts_register(struct device *dev, struct cpts *cpts,
-		  u32 mult, u32 shift)
+int cpts_register(struct cpts *cpts)
 {
-#ifdef CONFIG_TI_CPTS
 	int err, i;
-	unsigned long flags;
-
-	cpts->info = cpts_info;
-	cpts->clock = ptp_clock_register(&cpts->info, dev);
-	if (IS_ERR(cpts->clock)) {
-		err = PTR_ERR(cpts->clock);
-		cpts->clock = NULL;
-		return err;
-	}
-	spin_lock_init(&cpts->lock);
-
-	cpts->cc.read = cpts_systim_read;
-	cpts->cc.mask = CLOCKSOURCE_MASK(32);
-	cpts->cc_mult = mult;
-	cpts->cc.mult = mult;
-	cpts->cc.shift = shift;
 
 	INIT_LIST_HEAD(&cpts->events);
 	INIT_LIST_HEAD(&cpts->pool);
 	for (i = 0; i < CPTS_MAX_EVENTS; i++)
 		list_add(&cpts->pool_data[i].list, &cpts->pool);
 
-	cpts_clk_init(dev, cpts);
+	clk_enable(cpts->refclk);
+
 	cpts_write32(cpts, CPTS_EN, control);
 	cpts_write32(cpts, TS_PEND_EN, int_enable);
 
-	spin_lock_irqsave(&cpts->lock, flags);
 	timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
-	spin_unlock_irqrestore(&cpts->lock, flags);
-
-	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
-	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
 
+	cpts->clock = ptp_clock_register(&cpts->info, cpts->dev);
+	if (IS_ERR(cpts->clock)) {
+		err = PTR_ERR(cpts->clock);
+		cpts->clock = NULL;
+		goto err_ptp;
+	}
 	cpts->phc_index = ptp_clock_index(cpts->clock);
-#endif
+
+	schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
 	return 0;
+
+err_ptp:
+	clk_disable(cpts->refclk);
+	return err;
 }
+EXPORT_SYMBOL_GPL(cpts_register);
 
 void cpts_unregister(struct cpts *cpts)
 {
-#ifdef CONFIG_TI_CPTS
-	if (cpts->clock) {
-		ptp_clock_unregister(cpts->clock);
-		cancel_delayed_work_sync(&cpts->overflow_work);
+	if (WARN_ON(!cpts->clock))
+		return;
+
+	cancel_delayed_work_sync(&cpts->overflow_work);
+
+	ptp_clock_unregister(cpts->clock);
+	cpts->clock = NULL;
+
+	cpts_write32(cpts, 0, int_enable);
+	cpts_write32(cpts, 0, control);
+
+	clk_disable(cpts->refclk);
+}
+EXPORT_SYMBOL_GPL(cpts_unregister);
+
+static void cpts_calc_mult_shift(struct cpts *cpts)
+{
+	u64 frac, maxsec, ns;
+	u32 freq;
+
+	freq = clk_get_rate(cpts->refclk);
+
+	/* Calc the maximum number of seconds which we can run before
+	 * wrapping around.
+	 */
+	maxsec = cpts->cc.mask;
+	do_div(maxsec, freq);
+	/* limit conversation rate to 10 sec as higher values will produce
+	 * too small mult factors and so reduce the conversion accuracy
+	 */
+	if (maxsec > 10)
+		maxsec = 10;
+
+	/* Calc overflow check period (maxsec / 2) */
+	cpts->ov_check_period = (HZ * maxsec) / 2;
+	dev_info(cpts->dev, "cpts: overflow check period %lu (jiffies)\n",
+		 cpts->ov_check_period);
+
+	if (cpts->cc.mult || cpts->cc.shift)
+		return;
+
+	clocks_calc_mult_shift(&cpts->cc.mult, &cpts->cc.shift,
+			       freq, NSEC_PER_SEC, maxsec);
+
+	frac = 0;
+	ns = cyclecounter_cyc2ns(&cpts->cc, freq, cpts->cc.mask, &frac);
+
+	dev_info(cpts->dev,
+		 "CPTS: ref_clk_freq:%u calc_mult:%u calc_shift:%u error:%lld nsec/sec\n",
+		 freq, cpts->cc.mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
+}
+
+static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
+{
+	int ret = -EINVAL;
+	u32 prop;
+
+	if (!of_property_read_u32(node, "cpts_clock_mult", &prop))
+		cpts->cc.mult = prop;
+
+	if (!of_property_read_u32(node, "cpts_clock_shift", &prop))
+		cpts->cc.shift = prop;
+
+	if ((cpts->cc.mult && !cpts->cc.shift) ||
+	    (!cpts->cc.mult && cpts->cc.shift))
+		goto of_error;
+
+	return 0;
+
+of_error:
+	dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
+	return ret;
+}
+
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 struct device_node *node)
+{
+	struct cpts *cpts;
+	int ret;
+
+	cpts = devm_kzalloc(dev, sizeof(*cpts), GFP_KERNEL);
+	if (!cpts)
+		return ERR_PTR(-ENOMEM);
+
+	cpts->dev = dev;
+	cpts->reg = (struct cpsw_cpts __iomem *)regs;
+	spin_lock_init(&cpts->lock);
+	INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
+
+	ret = cpts_of_parse(cpts, node);
+	if (ret)
+		return ERR_PTR(ret);
+
+	cpts->refclk = devm_clk_get(dev, "cpts");
+	if (IS_ERR(cpts->refclk)) {
+		dev_err(dev, "Failed to get cpts refclk\n");
+		return ERR_PTR(PTR_ERR(cpts->refclk));
 	}
-	if (cpts->refclk)
-		cpts_clk_release(cpts);
-#endif
+
+	clk_prepare(cpts->refclk);
+
+	cpts->cc.read = cpts_systim_read;
+	cpts->cc.mask = CLOCKSOURCE_MASK(32);
+	cpts->info = cpts_info;
+
+	cpts_calc_mult_shift(cpts);
+	/* save cc.mult original value as it can be modified
+	 * by cpts_ptp_adjfreq().
+	 */
+	cpts->cc_mult = cpts->cc.mult;
+
+	return cpts;
 }
+EXPORT_SYMBOL_GPL(cpts_create);
+
+void cpts_release(struct cpts *cpts)
+{
+	if (!cpts)
+		return;
+
+	if (WARN_ON(!cpts->refclk))
+		return;
+
+	clk_unprepare(cpts->refclk);
+}
+EXPORT_SYMBOL_GPL(cpts_release);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI CPTS driver");
+MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");