fm10k: Add support for PTP

This change adds support for the Linux PTP Hardware clock and timestamping
functionality provided by the hardware.  There are actually two cases that
this timestamping is meant to support.

The first case would be an ordinary clock scenario.  In this configuration
the host interface does not have access to BAR 4.  However all of the host
interfaces should be locked into the same boundary clock region and as such
they are all on the same clock anyway.  With this being the case they can
synchronize among themselves and only need to adjust the offset since they
are all on the same clock with the same frequency.

The second case is a boundary clock scenario.  This is a special case and
would require both BAR 4 access, and a means of presenting a netdev per
boundary region.  The current plan is to use DSA at some point in the
future to provide these interfaces, but the DSA portion is still under
development.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/fm10k/Makefile

@@ -30,4 +30,4 @@ obj-$(CONFIG_FM10K) += fm10k.o
 fm10k-objs := fm10k_main.o fm10k_common.o fm10k_pci.o \
 	      fm10k_netdev.o fm10k_ethtool.o fm10k_pf.o fm10k_vf.o \
 	      fm10k_mbx.o fm10k_iov.o fm10k_tlv.o \
-	      fm10k_debugfs.o fm10k_dcbnl.o
+	      fm10k_debugfs.o fm10k_ptp.o fm10k_dcbnl.o

drivers/net/ethernet/intel/fm10k/fm10k.h

@@ -26,6 +26,9 @@
 #include <linux/rtnetlink.h>
 #include <linux/if_vlan.h>
 #include <linux/pci.h>
+#include <linux/net_tstamp.h>
+#include <linux/clocksource.h>
+#include <linux/ptp_clock_kernel.h>
 
 #include "fm10k_pf.h"
 #include "fm10k_vf.h"
@@ -293,6 +296,7 @@ struct fm10k_intfc {
 	struct fm10k_hw_stats stats;
 	struct fm10k_hw hw;
 	u32 __iomem *uc_addr;
+	u32 __iomem *sw_addr;
 	u16 msg_enable;
 	u16 tx_ring_count;
 	u16 rx_ring_count;
@@ -314,6 +318,20 @@ struct fm10k_intfc {
 	struct dentry *dbg_intfc;
 
 #endif /* CONFIG_DEBUG_FS */
+	struct ptp_clock_info ptp_caps;
+	struct ptp_clock *ptp_clock;
+
+	struct sk_buff_head ts_tx_skb_queue;
+	u32 tx_hwtstamp_timeouts;
+
+	struct hwtstamp_config ts_config;
+	/* We are unable to actually adjust the clock beyond the frequency
+	 * value.  Once the clock is started there is no resetting it.  As
+	 * such we maintain a separate offset from the actual hardware clock
+	 * to allow for offset adjustment.
+	 */
+	s64 ptp_adjust;
+	rwlock_t systime_lock;
 #ifdef CONFIG_DCB
 	u8 pfc_en;
 #endif
@@ -411,6 +429,10 @@ union fm10k_ftag_info {
 };
 
 struct fm10k_cb {
+	union {
+		__le64 tstamp;
+		unsigned long ts_tx_timeout;
+	};
 	union fm10k_ftag_info fi;
 };
 
@@ -492,6 +514,21 @@ static inline void fm10k_dbg_init(void) {}
 static inline void fm10k_dbg_exit(void) {}
 #endif /* CONFIG_DEBUG_FS */
 
+/* Time Stamping */
+void fm10k_systime_to_hwtstamp(struct fm10k_intfc *interface,
+			       struct skb_shared_hwtstamps *hwtstamp,
+			       u64 systime);
+void fm10k_ts_tx_enqueue(struct fm10k_intfc *interface, struct sk_buff *skb);
+void fm10k_ts_tx_hwtstamp(struct fm10k_intfc *interface, __le16 dglort,
+			  u64 systime);
+void fm10k_ts_reset(struct fm10k_intfc *interface);
+void fm10k_ts_init(struct fm10k_intfc *interface);
+void fm10k_ts_tx_subtask(struct fm10k_intfc *interface);
+void fm10k_ptp_register(struct fm10k_intfc *interface);
+void fm10k_ptp_unregister(struct fm10k_intfc *interface);
+int fm10k_get_ts_config(struct net_device *netdev, struct ifreq *ifr);
+int fm10k_set_ts_config(struct net_device *netdev, struct ifreq *ifr);
+
 /* DCB */
 void fm10k_dcbnl_set_ops(struct net_device *dev);
 #endif /* _FM10K_H_ */

drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c

@@ -91,6 +91,8 @@ static const struct fm10k_stats fm10k_gstrings_stats[] = {
 	FM10K_STAT("mbx_rx_messages", hw.mbx.rx_messages),
 	FM10K_STAT("mbx_rx_dwords", hw.mbx.rx_dwords),
 	FM10K_STAT("mbx_rx_parse_err", hw.mbx.rx_parse_err),
+
+	FM10K_STAT("tx_hwtstamp_timeouts", tx_hwtstamp_timeouts),
 };
 
 #define FM10K_GLOBAL_STATS_LEN ARRAY_SIZE(fm10k_gstrings_stats)
@@ -1006,6 +1008,33 @@ static int fm10k_set_channels(struct net_device *dev,
 	return fm10k_setup_tc(dev, netdev_get_num_tc(dev));
 }
 
+static int fm10k_get_ts_info(struct net_device *dev,
+			   struct ethtool_ts_info *info)
+{
+	struct fm10k_intfc *interface = netdev_priv(dev);
+
+	info->so_timestamping =
+		SOF_TIMESTAMPING_TX_SOFTWARE |
+		SOF_TIMESTAMPING_RX_SOFTWARE |
+		SOF_TIMESTAMPING_SOFTWARE |
+		SOF_TIMESTAMPING_TX_HARDWARE |
+		SOF_TIMESTAMPING_RX_HARDWARE |
+		SOF_TIMESTAMPING_RAW_HARDWARE;
+
+	if (interface->ptp_clock)
+		info->phc_index = ptp_clock_index(interface->ptp_clock);
+	else
+		info->phc_index = -1;
+
+	info->tx_types = (1 << HWTSTAMP_TX_OFF) |
+			 (1 << HWTSTAMP_TX_ON);
+
+	info->rx_filters = (1 << HWTSTAMP_FILTER_NONE) |
+			   (1 << HWTSTAMP_FILTER_ALL);
+
+	return 0;
+}
+
 static const struct ethtool_ops fm10k_ethtool_ops = {
 	.get_strings		= fm10k_get_strings,
 	.get_sset_count		= fm10k_get_sset_count,
@@ -1031,6 +1060,7 @@ static const struct ethtool_ops fm10k_ethtool_ops = {
 	.set_rxfh		= fm10k_set_rssh,
 	.get_channels		= fm10k_get_channels,
 	.set_channels		= fm10k_set_channels,
+	.get_ts_info            = fm10k_get_ts_info,
 };
 
 void fm10k_set_ethtool_ops(struct net_device *dev)

drivers/net/ethernet/intel/fm10k/fm10k_main.c

@@ -399,6 +399,19 @@ static inline void fm10k_rx_hash(struct fm10k_ring *ring,
 		     PKT_HASH_TYPE_L4 : PKT_HASH_TYPE_L3);
 }
 
+static void fm10k_rx_hwtstamp(struct fm10k_ring *rx_ring,
+			      union fm10k_rx_desc *rx_desc,
+			      struct sk_buff *skb)
+{
+	struct fm10k_intfc *interface = rx_ring->q_vector->interface;
+
+	FM10K_CB(skb)->tstamp = rx_desc->q.timestamp;
+
+	if (unlikely(interface->flags & FM10K_FLAG_RX_TS_ENABLED))
+		fm10k_systime_to_hwtstamp(interface, skb_hwtstamps(skb),
+					  le64_to_cpu(rx_desc->q.timestamp));
+}
+
 static void fm10k_type_trans(struct fm10k_ring *rx_ring,
 			     union fm10k_rx_desc *rx_desc,
 			     struct sk_buff *skb)
@@ -448,6 +461,8 @@ static unsigned int fm10k_process_skb_fields(struct fm10k_ring *rx_ring,
 
 	fm10k_rx_checksum(rx_ring, rx_desc, skb);
 
+	fm10k_rx_hwtstamp(rx_ring, rx_desc, skb);
+
 	FM10K_CB(skb)->fi.w.vlan = rx_desc->w.vlan;
 
 	skb_record_rx_queue(skb, rx_ring->queue_index);
@@ -886,6 +901,11 @@ static u8 fm10k_tx_desc_flags(struct sk_buff *skb, u32 tx_flags)
 	/* set type for advanced descriptor with frame checksum insertion */
 	u32 desc_flags = 0;
 
+	/* set timestamping bits */
+	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
+	    likely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
+			desc_flags |= FM10K_TXD_FLAG_TIME;
+
 	/* set checksum offload bits */
 	desc_flags |= FM10K_SET_FLAG(tx_flags, FM10K_TX_FLAGS_CSUM,
 				     FM10K_TXD_FLAG_CSUM);

drivers/net/ethernet/intel/fm10k/fm10k_netdev.c

@@ -243,6 +243,9 @@ void fm10k_clean_all_tx_rings(struct fm10k_intfc *interface)
 
 	for (i = 0; i < interface->num_tx_queues; i++)
 		fm10k_clean_tx_ring(interface->tx_ring[i]);
+
+	/* remove any stale timestamp buffers and free them */
+	skb_queue_purge(&interface->ts_tx_skb_queue);
 }
 
 /**
@@ -651,6 +654,10 @@ static netdev_tx_t fm10k_xmit_frame(struct sk_buff *skb, struct net_device *dev)
 		__skb_put(skb, pad_len);
 	}
 
+	/* prepare packet for hardware time stamping */
+	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP))
+		fm10k_ts_tx_enqueue(interface, skb);
+
 	if (r_idx >= interface->num_tx_queues)
 		r_idx %= interface->num_tx_queues;
 
@@ -1177,6 +1184,18 @@ int fm10k_setup_tc(struct net_device *dev, u8 tc)
 	return 0;
 }
 
+static int fm10k_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
+{
+	switch (cmd) {
+	case SIOCGHWTSTAMP:
+		return fm10k_get_ts_config(netdev, ifr);
+	case SIOCSHWTSTAMP:
+		return fm10k_set_ts_config(netdev, ifr);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static void fm10k_assign_l2_accel(struct fm10k_intfc *interface,
 				  struct fm10k_l2_accel *l2_accel)
 {
@@ -1345,6 +1364,7 @@ static const struct net_device_ops fm10k_netdev_ops = {
 	.ndo_get_vf_config	= fm10k_ndo_get_vf_config,
 	.ndo_add_vxlan_port	= fm10k_add_vxlan_port,
 	.ndo_del_vxlan_port	= fm10k_del_vxlan_port,
+	.ndo_do_ioctl		= fm10k_ioctl,
 	.ndo_dfwd_add_station	= fm10k_dfwd_add_station,
 	.ndo_dfwd_del_station	= fm10k_dfwd_del_station,
 };