Merge branch 'ti-cpts-update-and-fixes'

Grygorii Strashko says:

====================
net: ethernet: ti: cpts: update and fixes

It is preparation series intended to clean up and optimize TI CPTS driver to
facilitate further integration with other TI's SoCs like Keystone 2.

Changes in v5:
- fixed copy paste error in cpts_release
- reworked cc.mult/shift and cc_mult initialization

Changes in v4:
- fixed build error in patch
  "net: ethernet: ti: cpts: clean up event list if event pool is empty"
- rebased on top of net-next

Changes in v3:
- patches reordered: fixes and small updates moved first
- added comments in code about cpts->cc_mult
- conversation range (maxsec) limited to 10sec

Changes in v2:
- patch "net: ethernet: ti: cpts: rework initialization/deinitialization"
  was split on 4 patches
- applied comments from Richard Cochran
- dropped patch
  "net: ethernet: ti: cpts: add return value to tx and rx timestamp funcitons"
- new patches added:
  "net: ethernet: ti: cpts: drop excessive writes to CTRL and INT_EN regs"
  and "clocksource: export the clocks_calc_mult_shift to use by timestamp code"

Links on prev versions:
v4: https://lkml.org/lkml/2016/12/6/496
v3: https://www.spinics.net/lists/devicetree/msg153474.html
v2: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1282034.html
v1: http://www.spinics.net/lists/linux-omap/msg131925.html
====================
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/cpsw.txt

@@ -20,8 +20,6 @@ Required properties:
 - slaves		: Specifies number for slaves
 - active_slave		: Specifies the slave to use for time stamping,
 			  ethtool and SIOCGMIIPHY
-- cpts_clock_mult	: Numerator to convert input clock ticks into nanoseconds
-- cpts_clock_shift	: Denominator to convert input clock ticks into nanoseconds
 
 Optional properties:
 - ti,hwmods		: Must be "cpgmac0"
@@ -35,7 +33,11 @@ Optional properties:
 			  For example in dra72x-evm, pcf gpio has to be
 			  driven low so that cpsw slave 0 and phy data
 			  lines are connected via mux.
-
+- cpts_clock_mult	: Numerator to convert input clock ticks into nanoseconds
+- cpts_clock_shift	: Denominator to convert input clock ticks into nanoseconds
+			  Mult and shift will be calculated basing on CPTS
+			  rftclk frequency if both cpts_clock_shift and
+			  cpts_clock_mult properties are not provided.
 
 Slave Properties:
 Required properties:

drivers/net/ethernet/ti/Kconfig

@@ -74,7 +74,7 @@ config TI_CPSW
 	  will be called cpsw.
 
 config TI_CPTS
-	bool "TI Common Platform Time Sync (CPTS) Support"
+	tristate "TI Common Platform Time Sync (CPTS) Support"
 	depends on TI_CPSW
 	select PTP_1588_CLOCK
 	---help---

drivers/net/ethernet/ti/Makefile

@@ -12,8 +12,9 @@ obj-$(CONFIG_TI_DAVINCI_MDIO) += davinci_mdio.o
 obj-$(CONFIG_TI_DAVINCI_CPDMA) += davinci_cpdma.o
 obj-$(CONFIG_TI_CPSW_PHY_SEL) += cpsw-phy-sel.o
 obj-$(CONFIG_TI_CPSW_ALE) += cpsw_ale.o
+obj-$(CONFIG_TI_CPTS) += cpts.o
 obj-$(CONFIG_TI_CPSW) += ti_cpsw.o
-ti_cpsw-y := cpsw.o cpts.o
+ti_cpsw-y := cpsw.o
 
 obj-$(CONFIG_TI_KEYSTONE_NETCP) += keystone_netcp.o
 keystone_netcp-y := netcp_core.o

drivers/net/ethernet/ti/cpsw.c

@@ -1487,9 +1487,7 @@ static int cpsw_ndo_open(struct net_device *ndev)
 		if (ret < 0)
 			goto err_cleanup;
 
-		if (cpts_register(cpsw->dev, cpsw->cpts,
-				  cpsw->data.cpts_clock_mult,
-				  cpsw->data.cpts_clock_shift))
+		if (cpts_register(cpsw->cpts))
 			dev_err(priv->dev, "error registering cpts device\n");
 
 	}
@@ -1562,7 +1560,7 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb,
 	}
 
 	if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
-				cpsw->cpts->tx_enable)
+	    cpts_is_tx_enabled(cpsw->cpts))
 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
 
 	skb_tx_timestamp(skb);
@@ -1594,14 +1592,15 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb,
 	return NETDEV_TX_BUSY;
 }
 
-#ifdef CONFIG_TI_CPTS
+#if IS_ENABLED(CONFIG_TI_CPTS)
 
 static void cpsw_hwtstamp_v1(struct cpsw_common *cpsw)
 {
 	struct cpsw_slave *slave = &cpsw->slaves[cpsw->data.active_slave];
 	u32 ts_en, seq_id;
 
-	if (!cpsw->cpts->tx_enable && !cpsw->cpts->rx_enable) {
+	if (!cpts_is_tx_enabled(cpsw->cpts) &&
+	    !cpts_is_rx_enabled(cpsw->cpts)) {
 		slave_write(slave, 0, CPSW1_TS_CTL);
 		return;
 	}
@@ -1609,10 +1608,10 @@ static void cpsw_hwtstamp_v1(struct cpsw_common *cpsw)
 	seq_id = (30 << CPSW_V1_SEQ_ID_OFS_SHIFT) | ETH_P_1588;
 	ts_en = EVENT_MSG_BITS << CPSW_V1_MSG_TYPE_OFS;
 
-	if (cpsw->cpts->tx_enable)
+	if (cpts_is_tx_enabled(cpsw->cpts))
 		ts_en |= CPSW_V1_TS_TX_EN;
 
-	if (cpsw->cpts->rx_enable)
+	if (cpts_is_rx_enabled(cpsw->cpts))
 		ts_en |= CPSW_V1_TS_RX_EN;
 
 	slave_write(slave, ts_en, CPSW1_TS_CTL);
@@ -1635,20 +1634,20 @@ static void cpsw_hwtstamp_v2(struct cpsw_priv *priv)
 	case CPSW_VERSION_2:
 		ctrl &= ~CTRL_V2_ALL_TS_MASK;
 
-		if (cpsw->cpts->tx_enable)
+		if (cpts_is_tx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V2_TX_TS_BITS;
 
-		if (cpsw->cpts->rx_enable)
+		if (cpts_is_rx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V2_RX_TS_BITS;
 		break;
 	case CPSW_VERSION_3:
 	default:
 		ctrl &= ~CTRL_V3_ALL_TS_MASK;
 
-		if (cpsw->cpts->tx_enable)
+		if (cpts_is_tx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V3_TX_TS_BITS;
 
-		if (cpsw->cpts->rx_enable)
+		if (cpts_is_rx_enabled(cpsw->cpts))
 			ctrl |= CTRL_V3_RX_TS_BITS;
 		break;
 	}
@@ -1684,7 +1683,7 @@ static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 
 	switch (cfg.rx_filter) {
 	case HWTSTAMP_FILTER_NONE:
-		cpts->rx_enable = 0;
+		cpts_rx_enable(cpts, 0);
 		break;
 	case HWTSTAMP_FILTER_ALL:
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
@@ -1700,14 +1699,14 @@ static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
-		cpts->rx_enable = 1;
+		cpts_rx_enable(cpts, 1);
 		cfg.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
 		break;
 	default:
 		return -ERANGE;
 	}
 
-	cpts->tx_enable = cfg.tx_type == HWTSTAMP_TX_ON;
+	cpts_tx_enable(cpts, cfg.tx_type == HWTSTAMP_TX_ON);
 
 	switch (cpsw->version) {
 	case CPSW_VERSION_1:
@@ -1736,13 +1735,23 @@ static int cpsw_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
 		return -EOPNOTSUPP;
 
 	cfg.flags = 0;
-	cfg.tx_type = cpts->tx_enable ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
-	cfg.rx_filter = (cpts->rx_enable ?
+	cfg.tx_type = cpts_is_tx_enabled(cpts) ?
+		      HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
+	cfg.rx_filter = (cpts_is_rx_enabled(cpts) ?
 			 HWTSTAMP_FILTER_PTP_V2_EVENT : HWTSTAMP_FILTER_NONE);
 
 	return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
 }
+#else
+static int cpsw_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
+{
+	return -EOPNOTSUPP;
+}
 
+static int cpsw_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
+{
+	return -EOPNOTSUPP;
+}
 #endif /*CONFIG_TI_CPTS*/
 
 static int cpsw_ndo_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
@@ -1755,12 +1764,10 @@ static int cpsw_ndo_ioctl(struct net_device *dev, struct ifreq *req, int cmd)
 		return -EINVAL;
 
 	switch (cmd) {
-#ifdef CONFIG_TI_CPTS
 	case SIOCSHWTSTAMP:
 		return cpsw_hwtstamp_set(dev, req);
 	case SIOCGHWTSTAMP:
 		return cpsw_hwtstamp_get(dev, req);
-#endif
 	}
 
 	if (!cpsw->slaves[slave_no].phy)
@@ -2100,10 +2107,10 @@ static void cpsw_set_msglevel(struct net_device *ndev, u32 value)
 	priv->msg_enable = value;
 }
 
+#if IS_ENABLED(CONFIG_TI_CPTS)
 static int cpsw_get_ts_info(struct net_device *ndev,
 			    struct ethtool_ts_info *info)
 {
-#ifdef CONFIG_TI_CPTS
 	struct cpsw_common *cpsw = ndev_to_cpsw(ndev);
 
 	info->so_timestamping =
@@ -2120,7 +2127,12 @@ static int cpsw_get_ts_info(struct net_device *ndev,
 	info->rx_filters =
 		(1 << HWTSTAMP_FILTER_NONE) |
 		(1 << HWTSTAMP_FILTER_PTP_V2_EVENT);
+	return 0;
+}
 #else
+static int cpsw_get_ts_info(struct net_device *ndev,
+			    struct ethtool_ts_info *info)
+{
 	info->so_timestamping =
 		SOF_TIMESTAMPING_TX_SOFTWARE |
 		SOF_TIMESTAMPING_RX_SOFTWARE |
@@ -2128,9 +2140,9 @@ static int cpsw_get_ts_info(struct net_device *ndev,
 	info->phc_index = -1;
 	info->tx_types = 0;
 	info->rx_filters = 0;
-#endif
 	return 0;
 }
+#endif
 
 static int cpsw_get_link_ksettings(struct net_device *ndev,
 				   struct ethtool_link_ksettings *ecmd)
@@ -2512,18 +2524,6 @@ static int cpsw_probe_dt(struct cpsw_platform_data *data,
 	}
 	data->active_slave = prop;
 
-	if (of_property_read_u32(node, "cpts_clock_mult", &prop)) {
-		dev_err(&pdev->dev, "Missing cpts_clock_mult property in the DT.\n");
-		return -EINVAL;
-	}
-	data->cpts_clock_mult = prop;
-
-	if (of_property_read_u32(node, "cpts_clock_shift", &prop)) {
-		dev_err(&pdev->dev, "Missing cpts_clock_shift property in the DT.\n");
-		return -EINVAL;
-	}
-	data->cpts_clock_shift = prop;
-
 	data->slave_data = devm_kzalloc(&pdev->dev, data->slaves
 					* sizeof(struct cpsw_slave_data),
 					GFP_KERNEL);
@@ -2782,6 +2782,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	struct cpdma_params		dma_params;
 	struct cpsw_ale_params		ale_params;
 	void __iomem			*ss_regs;
+	void __iomem			*cpts_regs;
 	struct resource			*res, *ss_res;
 	const struct of_device_id	*of_id;
 	struct gpio_descs		*mode;
@@ -2809,12 +2810,6 @@ static int cpsw_probe(struct platform_device *pdev)
 	priv->dev  = &ndev->dev;
 	priv->msg_enable = netif_msg_init(debug_level, CPSW_DEBUG);
 	cpsw->rx_packet_max = max(rx_packet_max, 128);
-	cpsw->cpts = devm_kzalloc(&pdev->dev, sizeof(struct cpts), GFP_KERNEL);
-	if (!cpsw->cpts) {
-		dev_err(&pdev->dev, "error allocating cpts\n");
-		ret = -ENOMEM;
-		goto clean_ndev_ret;
-	}
 
 	mode = devm_gpiod_get_array_optional(&pdev->dev, "mode", GPIOD_OUT_LOW);
 	if (IS_ERR(mode)) {
@@ -2902,7 +2897,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	switch (cpsw->version) {
 	case CPSW_VERSION_1:
 		cpsw->host_port_regs = ss_regs + CPSW1_HOST_PORT_OFFSET;
-		cpsw->cpts->reg      = ss_regs + CPSW1_CPTS_OFFSET;
+		cpts_regs		= ss_regs + CPSW1_CPTS_OFFSET;
 		cpsw->hw_stats	     = ss_regs + CPSW1_HW_STATS;
 		dma_params.dmaregs   = ss_regs + CPSW1_CPDMA_OFFSET;
 		dma_params.txhdp     = ss_regs + CPSW1_STATERAM_OFFSET;
@@ -2916,7 +2911,7 @@ static int cpsw_probe(struct platform_device *pdev)
 	case CPSW_VERSION_3:
 	case CPSW_VERSION_4:
 		cpsw->host_port_regs = ss_regs + CPSW2_HOST_PORT_OFFSET;
-		cpsw->cpts->reg      = ss_regs + CPSW2_CPTS_OFFSET;
+		cpts_regs		= ss_regs + CPSW2_CPTS_OFFSET;
 		cpsw->hw_stats	     = ss_regs + CPSW2_HW_STATS;
 		dma_params.dmaregs   = ss_regs + CPSW2_CPDMA_OFFSET;
 		dma_params.txhdp     = ss_regs + CPSW2_STATERAM_OFFSET;
@@ -2983,6 +2978,12 @@ static int cpsw_probe(struct platform_device *pdev)
 		goto clean_dma_ret;
 	}
 
+	cpsw->cpts = cpts_create(cpsw->dev, cpts_regs, cpsw->dev->of_node);
+	if (IS_ERR(cpsw->cpts)) {
+		ret = PTR_ERR(cpsw->cpts);
+		goto clean_ale_ret;
+	}
+
 	ndev->irq = platform_get_irq(pdev, 1);
 	if (ndev->irq < 0) {
 		dev_err(priv->dev, "error getting irq resource\n");
@@ -3098,6 +3099,7 @@ static int cpsw_remove(struct platform_device *pdev)
 		unregister_netdev(cpsw->slaves[1].ndev);
 	unregister_netdev(ndev);
 
+	cpts_release(cpsw->cpts);
 	cpsw_ale_destroy(cpsw->ale);
 	cpdma_ctlr_destroy(cpsw->dma);
 	cpsw_remove_dt(pdev);

drivers/net/ethernet/ti/cpsw.h

@@ -31,8 +31,6 @@ struct cpsw_platform_data {
 	u32	channels;	/* number of cpdma channels (symmetric) */
 	u32	slaves;		/* number of slave cpgmac ports */
 	u32	active_slave; /* time stamping, ethtool and SIOCGMIIPHY slave */
-	u32	cpts_clock_mult;  /* convert input clock ticks to nanoseconds */
-	u32	cpts_clock_shift; /* convert input clock ticks to nanoseconds */
 	u32	ale_entries;	/* ale table size */
 	u32	bd_ram_size;  /*buffer descriptor ram size */
 	u32	mac_control;	/* Mac control register */

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>");

drivers/net/ethernet/ti/cpts.h

@@ -20,11 +20,14 @@
 #ifndef _TI_CPTS_H_
 #define _TI_CPTS_H_
 
+#if IS_ENABLED(CONFIG_TI_CPTS)
+
 #include <linux/clk.h>
 #include <linux/clkdev.h>
 #include <linux/clocksource.h>
 #include <linux/device.h>
 #include <linux/list.h>
+#include <linux/of.h>
 #include <linux/ptp_clock_kernel.h>
 #include <linux/skbuff.h>
 #include <linux/timecounter.h>
@@ -94,9 +97,6 @@ enum {
 	CPTS_EV_TX,   /* Ethernet Transmit Event */
 };
 
-/* This covers any input clock up to about 500 MHz. */
-#define CPTS_OVERFLOW_PERIOD (HZ * 8)
-
 #define CPTS_FIFO_DEPTH 16
 #define CPTS_MAX_EVENTS 32
 
@@ -108,10 +108,10 @@ struct cpts_event {
 };
 
 struct cpts {
+	struct device *dev;
 	struct cpsw_cpts __iomem *reg;
 	int tx_enable;
 	int rx_enable;
-#ifdef CONFIG_TI_CPTS
 	struct ptp_clock_info info;
 	struct ptp_clock *clock;
 	spinlock_t lock; /* protects time registers */
@@ -124,22 +124,86 @@ struct cpts {
 	struct list_head events;
 	struct list_head pool;
 	struct cpts_event pool_data[CPTS_MAX_EVENTS];
-#endif
+	unsigned long ov_check_period;
 };
 
-#ifdef CONFIG_TI_CPTS
 void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb);
 void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb);
+int cpts_register(struct cpts *cpts);
+void cpts_unregister(struct cpts *cpts);
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 struct device_node *node);
+void cpts_release(struct cpts *cpts);
+
+static inline void cpts_rx_enable(struct cpts *cpts, int enable)
+{
+	cpts->rx_enable = enable;
+}
+
+static inline bool cpts_is_rx_enabled(struct cpts *cpts)
+{
+	return !!cpts->rx_enable;
+}
+
+static inline void cpts_tx_enable(struct cpts *cpts, int enable)
+{
+	cpts->tx_enable = enable;
+}
+
+static inline bool cpts_is_tx_enabled(struct cpts *cpts)
+{
+	return !!cpts->tx_enable;
+}
+
 #else
+struct cpts;
+
 static inline void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 }
 static inline void cpts_tx_timestamp(struct cpts *cpts, struct sk_buff *skb)
 {
 }
+
+static inline
+struct cpts *cpts_create(struct device *dev, void __iomem *regs,
+			 struct device_node *node)
+{
+	return NULL;
+}
+
+static inline void cpts_release(struct cpts *cpts)
+{
+}
+
+static inline int
+cpts_register(struct cpts *cpts)
+{
+	return 0;
+}
+
+static inline void cpts_unregister(struct cpts *cpts)
+{
+}
+
+static inline void cpts_rx_enable(struct cpts *cpts, int enable)
+{
+}
+
+static inline bool cpts_is_rx_enabled(struct cpts *cpts)
+{
+	return false;
+}
+
+static inline void cpts_tx_enable(struct cpts *cpts, int enable)
+{
+}
+
+static inline bool cpts_is_tx_enabled(struct cpts *cpts)
+{
+	return false;
+}
 #endif
 
-int cpts_register(struct device *dev, struct cpts *cpts, u32 mult, u32 shift);
-void cpts_unregister(struct cpts *cpts);
 
 #endif

kernel/time/clocksource.c

@@ -89,6 +89,7 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec)
 	*mult = tmp;
 	*shift = sft;
 }
+EXPORT_SYMBOL_GPL(clocks_calc_mult_shift);
 
 /*[Clocksource internal variables]---------
  * curr_clocksource: