stmmac: add IEEE PTPv1 and PTPv2 support.

This patch enhances the stmmac driver to support IEEE 1588-2002
PTP (Precision Time Protocol) version 1 and IEEE 1588-2008 PPT
version 2.

Precision Time Protocol(PTP),which enables precise synchronization
of clocks in measurement and control systems implemented with
technologies such as network communication,local computing,
& distributed objects.

Both PTPv1 and PTPv2 is selected at run-time using the HW capability
register.

The PTPv1 TimeStamp support can be used on chips that have the normal
descriptor structures and PTPv2 TimeStamp support can be used on chips
that have the Extended descriptors(DES4-5-6-7). All such sanity checks
are done and verified by using HW capability register.

V2: in this version the ethtool support has been included in this patch;
Koptions have been completely removed (previously added to select
PTP and PTPv2). PTPv1 and PTPv2 is now added in a single patch instead of
two patches.
get_timestamp() and get_systemtime() L/H have been combined into single APIs.

Signed-off-by: Rayagond Kokatanur <rayagond@vayavyalabs.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 369 insertions, 15 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 180eed7168c1..6906772069e3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -47,6 +47,8 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #endif
+#include <linux/net_tstamp.h>
+#include "stmmac_ptp.h"
 #include "stmmac.h"
 
 #undef STMMAC_DEBUG
@@ -311,6 +313,327 @@ static void stmmac_eee_adjust(struct stmmac_priv *priv)
 		priv->hw->mac->set_eee_pls(priv->ioaddr, priv->phydev->link);
 }
 
+/* stmmac_get_tx_hwtstamp:
+ * @priv : pointer to private device structure.
+ * @entry : descriptor index to be used.
+ * @skb : the socket buffer
+ * Description :
+ * This function will read timestamp from the descriptor & pass it to stack.
+ * and also perform some sanity checks.
+ */
+static void stmmac_get_tx_hwtstamp(struct stmmac_priv *priv,
+				   unsigned int entry,
+				   struct sk_buff *skb)
+{
+	struct skb_shared_hwtstamps shhwtstamp;
+	u64 ns;
+	void *desc = NULL;
+
+	if (!priv->hwts_tx_en)
+		return;
+
+	/* if skb doesn't support hw tstamp */
+	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)))
+		return;
+
+	if (priv->adv_ts)
+		desc = (priv->dma_etx + entry);
+	else
+		desc = (priv->dma_tx + entry);
+
+	/* check tx tstamp status */
+	if (!priv->hw->desc->get_tx_timestamp_status((struct dma_desc *)desc))
+		return;
+
+	/* get the valid tstamp */
+	ns = priv->hw->desc->get_timestamp(desc, priv->adv_ts);
+
+	memset(&shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
+	shhwtstamp.hwtstamp = ns_to_ktime(ns);
+	/* pass tstamp to stack */
+	skb_tstamp_tx(skb, &shhwtstamp);
+
+	return;
+}
+
+/* stmmac_get_rx_hwtstamp:
+ * @priv : pointer to private device structure.
+ * @entry : descriptor index to be used.
+ * @skb : the socket buffer
+ * Description :
+ * This function will read received packet's timestamp from the descriptor
+ * and pass it to stack. It also perform some sanity checks.
+ */
+static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv,
+				   unsigned int entry,
+				   struct sk_buff *skb)
+{
+	struct skb_shared_hwtstamps *shhwtstamp = NULL;
+	u64 ns;
+	void *desc = NULL;
+
+	if (!priv->hwts_rx_en)
+		return;
+
+	if (priv->adv_ts)
+		desc = (priv->dma_erx + entry);
+	else
+		desc = (priv->dma_rx + entry);
+
+	/* if rx tstamp is not valid */
+	if (!priv->hw->desc->get_rx_timestamp_status(desc, priv->adv_ts))
+		return;
+
+	/* get valid tstamp */
+	ns = priv->hw->desc->get_timestamp(desc, priv->adv_ts);
+	shhwtstamp = skb_hwtstamps(skb);
+	memset(shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
+	shhwtstamp->hwtstamp = ns_to_ktime(ns);
+}
+
+/**
+ *  stmmac_hwtstamp_ioctl - control hardware timestamping.
+ *  @dev: device pointer.
+ *  @ifr: An IOCTL specefic structure, that can contain a pointer to
+ *  a proprietary structure used to pass information to the driver.
+ *  Description:
+ *  This function configures the MAC to enable/disable both outgoing(TX)
+ *  and incoming(RX) packets time stamping based on user input.
+ *  Return Value:
+ *  0 on success and an appropriate -ve integer on failure.
+ */
+static int stmmac_hwtstamp_ioctl(struct net_device *dev, struct ifreq *ifr)
+{
+	struct stmmac_priv *priv = netdev_priv(dev);
+	struct hwtstamp_config config;
+	struct timespec now;
+	u64 temp = 0;
+	u32 ptp_v2 = 0;
+	u32 tstamp_all = 0;
+	u32 ptp_over_ipv4_udp = 0;
+	u32 ptp_over_ipv6_udp = 0;
+	u32 ptp_over_ethernet = 0;
+	u32 snap_type_sel = 0;
+	u32 ts_master_en = 0;
+	u32 ts_event_en = 0;
+	u32 value = 0;
+
+	if (!(priv->dma_cap.time_stamp || priv->adv_ts)) {
+		netdev_alert(priv->dev, "No support for HW time stamping\n");
+		priv->hwts_tx_en = 0;
+		priv->hwts_rx_en = 0;
+
+		return -EOPNOTSUPP;
+	}
+
+	if (copy_from_user(&config, ifr->ifr_data,
+		sizeof(struct hwtstamp_config)))
+		return -EFAULT;
+
+	pr_debug("%s config flags:0x%x, tx_type:0x%x, rx_filter:0x%x\n",
+		 __func__, config.flags, config.tx_type, config.rx_filter);
+
+	/* reserved for future extensions */
+	if (config.flags)
+		return -EINVAL;
+
+	switch (config.tx_type) {
+	case HWTSTAMP_TX_OFF:
+		priv->hwts_tx_en = 0;
+		break;
+	case HWTSTAMP_TX_ON:
+		priv->hwts_tx_en = 1;
+		break;
+	default:
+		return -ERANGE;
+	}
+
+	if (priv->adv_ts) {
+		switch (config.rx_filter) {
+		/* time stamp no incoming packet at all */
+		case HWTSTAMP_FILTER_NONE:
+			config.rx_filter = HWTSTAMP_FILTER_NONE;
+			break;
+
+		/* PTP v1, UDP, any kind of event packet */
+		case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
+			/* take time stamp for all event messages */
+			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v1, UDP, Sync packet */
+		case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_SYNC;
+			/* take time stamp for SYNC messages only */
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v1, UDP, Delay_req packet */
+		case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ;
+			/* take time stamp for Delay_Req messages only */
+			ts_master_en = PTP_TCR_TSMSTRENA;
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v2, UDP, any kind of event packet */
+		case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for all event messages */
+			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v2, UDP, Sync packet */
+		case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_SYNC;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for SYNC messages only */
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v2, UDP, Delay_req packet */
+		case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for Delay_Req messages only */
+			ts_master_en = PTP_TCR_TSMSTRENA;
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			break;
+
+		/* PTP v2/802.AS1, any layer, any kind of event packet */
+		case HWTSTAMP_FILTER_PTP_V2_EVENT:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for all event messages */
+			snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			ptp_over_ethernet = PTP_TCR_TSIPENA;
+			break;
+
+		/* PTP v2/802.AS1, any layer, Sync packet */
+		case HWTSTAMP_FILTER_PTP_V2_SYNC:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_SYNC;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for SYNC messages only */
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			ptp_over_ethernet = PTP_TCR_TSIPENA;
+			break;
+
+		/* PTP v2/802.AS1, any layer, Delay_req packet */
+		case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V2_DELAY_REQ;
+			ptp_v2 = PTP_TCR_TSVER2ENA;
+			/* take time stamp for Delay_Req messages only */
+			ts_master_en = PTP_TCR_TSMSTRENA;
+			ts_event_en = PTP_TCR_TSEVNTENA;
+
+			ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
+			ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
+			ptp_over_ethernet = PTP_TCR_TSIPENA;
+			break;
+
+		/* time stamp any incoming packet */
+		case HWTSTAMP_FILTER_ALL:
+			config.rx_filter = HWTSTAMP_FILTER_ALL;
+			tstamp_all = PTP_TCR_TSENALL;
+			break;
+
+		default:
+			return -ERANGE;
+		}
+	} else {
+		switch (config.rx_filter) {
+		case HWTSTAMP_FILTER_NONE:
+			config.rx_filter = HWTSTAMP_FILTER_NONE;
+			break;
+		default:
+			/* PTP v1, UDP, any kind of event packet */
+			config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
+			break;
+		}
+	}
+	priv->hwts_rx_en = ((config.rx_filter == HWTSTAMP_FILTER_NONE) ? 0 : 1);
+
+	if (!priv->hwts_tx_en && !priv->hwts_rx_en)
+		priv->hw->ptp->config_hw_tstamping(priv->ioaddr, 0);
+	else {
+		value = (PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | PTP_TCR_TSCTRLSSR |
+			tstamp_all | ptp_v2 | ptp_over_ethernet |
+			ptp_over_ipv6_udp | ptp_over_ipv4_udp | ts_event_en |
+			ts_master_en | snap_type_sel);
+
+		priv->hw->ptp->config_hw_tstamping(priv->ioaddr, value);
+
+		/* program Sub Second Increment reg */
+		priv->hw->ptp->config_sub_second_increment(priv->ioaddr);
+
+		/* calculate default added value:
+		 * formula is :
+		 * addend = (2^32)/freq_div_ratio;
+		 * where, freq_div_ratio = STMMAC_SYSCLOCK/50MHz
+		 * hence, addend = ((2^32) * 50MHz)/STMMAC_SYSCLOCK;
+		 * NOTE: STMMAC_SYSCLOCK should be >= 50MHz to
+		 *       achive 20ns accuracy.
+		 *
+		 * 2^x * y == (y << x), hence
+		 * 2^32 * 50000000 ==> (50000000 << 32)
+		 */
+		temp = (u64)(50000000ULL << 32);
+		priv->default_addend = div_u64(temp, STMMAC_SYSCLOCK);
+		priv->hw->ptp->config_addend(priv->ioaddr,
+					     priv->default_addend);
+
+		/* initialize system time */
+		getnstimeofday(&now);
+		priv->hw->ptp->init_systime(priv->ioaddr, now.tv_sec,
+					    now.tv_nsec);
+	}
+
+	return copy_to_user(ifr->ifr_data, &config,
+			    sizeof(struct hwtstamp_config)) ? -EFAULT : 0;
+}
+
+static void stmmac_init_ptp(struct stmmac_priv *priv)
+{
+	if (priv->dma_cap.time_stamp) {
+		pr_debug("IEEE 1588-2002 Time Stamp supported\n");
+		priv->adv_ts = 0;
+	}
+	if (priv->dma_cap.atime_stamp && priv->extend_desc) {
+		pr_debug("IEEE 1588-2008 Advanced Time Stamp supported\n");
+		priv->adv_ts = 1;
+	}
+
+	priv->hw->ptp = &stmmac_ptp;
+	priv->hwts_tx_en = 0;
+	priv->hwts_rx_en = 0;
+}
+
 /**
  * stmmac_adjust_link
  * @dev: net device structure
@@ -856,6 +1179,8 @@ static void stmmac_tx_clean(struct stmmac_priv *priv)
 				priv->xstats.tx_pkt_n++;
 			} else
 				priv->dev->stats.tx_errors++;
+
+			stmmac_get_tx_hwtstamp(priv, entry, skb);
 		}
 		TX_DBG("%s: curr %d, dirty %d\n", __func__,
 			priv->cur_tx, priv->dirty_tx);
@@ -867,8 +1192,7 @@ static void stmmac_tx_clean(struct stmmac_priv *priv)
 					 DMA_TO_DEVICE);
 			priv->tx_skbuff_dma[entry] = 0;
 		}
-		if (priv->mode == STMMAC_RING_MODE)
-			priv->hw->ring->clean_desc3(p);
+		priv->hw->ring->clean_desc3(priv, p);
 
 		if (likely(skb != NULL)) {
 			dev_kfree_skb(skb);
@@ -1243,6 +1567,8 @@ static int stmmac_open(struct net_device *dev)
 
 	stmmac_mmc_setup(priv);
 
+	stmmac_init_ptp(priv);
+
 #ifdef CONFIG_STMMAC_DEBUG_FS
 	ret = stmmac_init_fs(dev);
 	if (ret < 0)
@@ -1507,7 +1833,15 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	dev->stats.tx_bytes += skb->len;
 
-	skb_tx_timestamp(skb);
+	if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
+		     priv->hwts_tx_en)) {
+		/* declare that device is doing timestamping */
+		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
+		priv->hw->desc->enable_tx_timestamp(first);
+	}
+
+	if (!priv->hwts_tx_en)
+		skb_tx_timestamp(skb);
 
 	priv->hw->dma->enable_dma_transmission(priv->ioaddr);
 
@@ -1545,9 +1879,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv)
 
 			p->des2 = priv->rx_skbuff_dma[entry];
 
-			if (unlikely((priv->mode == STMMAC_RING_MODE) &&
-				     (priv->plat->has_gmac)))
-				priv->hw->ring->refill_desc3(bfsize, p);
+			priv->hw->ring->refill_desc3(priv, p);
 
 			RX_DBG(KERN_INFO "\trefill entry #%d\n", entry);
 		}
@@ -1604,9 +1936,20 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit)
 							   &priv->xstats,
 							   priv->dma_erx +
 							   entry);
-		if (unlikely(status == discard_frame))
+		if (unlikely(status == discard_frame)) {
 			priv->dev->stats.rx_errors++;
-		else {
+			if (priv->hwts_rx_en && !priv->extend_desc) {
+				/* DESC2 & DESC3 will be overwitten by device
+				 * with timestamp value, hence reinitialize
+				 * them in stmmac_rx_refill() function so that
+				 * device can reuse it.
+				 */
+				priv->rx_skbuff[entry] = NULL;
+				dma_unmap_single(priv->device,
+					priv->rx_skbuff_dma[entry],
+					priv->dma_buf_sz, DMA_FROM_DEVICE);
+			}
+		} else {
 			struct sk_buff *skb;
 			int frame_len;
 
@@ -1635,6 +1978,8 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit)
 			prefetch(skb->data - NET_IP_ALIGN);
 			priv->rx_skbuff[entry] = NULL;
 
+			stmmac_get_rx_hwtstamp(priv, entry, skb);
+
 			skb_put(skb, frame_len);
 			dma_unmap_single(priv->device,
 					 priv->rx_skbuff_dma[entry],
@@ -1855,21 +2200,30 @@ static void stmmac_poll_controller(struct net_device *dev)
  *  a proprietary structure used to pass information to the driver.
  *  @cmd: IOCTL command
  *  Description:
- *  Currently there are no special functionality supported in IOCTL, just the
- *  phy_mii_ioctl(...) can be invoked.
+ *  Currently it supports just the phy_mii_ioctl(...) and HW time stamping.
  */
 static int stmmac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
-	int ret;
+	int ret = -EOPNOTSUPP;
 
 	if (!netif_running(dev))
 		return -EINVAL;
 
-	if (!priv->phydev)
-		return -EINVAL;
-
-	ret = phy_mii_ioctl(priv->phydev, rq, cmd);
+	switch (cmd) {
+	case SIOCGMIIPHY:
+	case SIOCGMIIREG:
+	case SIOCSMIIREG:
+		if (!priv->phydev)
+			return -EINVAL;
+		ret = phy_mii_ioctl(priv->phydev, rq, cmd);
+		break;
+	case SIOCSHWTSTAMP:
+		ret = stmmac_hwtstamp_ioctl(dev, rq);
+		break;
+	default:
+		break;
+	}
 
 	return ret;
 }