text: // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  /* Copyright (c) 2019 Mellanox Technologies. All rights reserved */
  
  #include <linux/ptp_clock_kernel.h>
  #include <linux/clocksource.h>
  #include <linux/timecounter.h>
  #include <linux/spinlock.h>
  #include <linux/device.h>
  #include <linux/rhashtable.h>
  #include <linux/ptp_classify.h>
  #include <linux/if_ether.h>
  #include <linux/if_vlan.h>
  #include <linux/net_tstamp.h>
  
  #include "spectrum.h"
  #include "spectrum_ptp.h"
  #include "core.h"
  
  #define MLXSW_SP1_PTP_CLOCK_CYCLES_SHIFT	29
  #define MLXSW_SP1_PTP_CLOCK_FREQ_KHZ		156257 /* 6.4nSec */
  #define MLXSW_SP1_PTP_CLOCK_MASK		64
  
  #define MLXSW_SP1_PTP_HT_GC_INTERVAL		500 /* ms */
  
  /* How long, approximately, should the unmatched entries stay in the hash table
   * before they are collected. Should be evenly divisible by the GC interval.
   */
  #define MLXSW_SP1_PTP_HT_GC_TIMEOUT		1000 /* ms */
  
  struct mlxsw_sp_ptp_state {
  	struct mlxsw_sp *mlxsw_sp;
  	struct rhltable unmatched_ht;
  	spinlock_t unmatched_lock; /* protects the HT */
  	struct delayed_work ht_gc_dw;
  	u32 gc_cycle;
  };
  
  struct mlxsw_sp1_ptp_key {
  	u16 local_port;
  	u8 message_type;
  	u16 sequence_id;
  	u8 domain_number;
  	bool ingress;
  };
  
  struct mlxsw_sp1_ptp_unmatched {
  	struct mlxsw_sp1_ptp_key key;
  	struct rhlist_head ht_node;
  	struct rcu_head rcu;
  	struct sk_buff *skb;
  	u64 timestamp;
  	u32 gc_cycle;
  };
  
  static const struct rhashtable_params mlxsw_sp1_ptp_unmatched_ht_params = {
  	.key_len = sizeof_field(struct mlxsw_sp1_ptp_unmatched, key),
  	.key_offset = offsetof(struct mlxsw_sp1_ptp_unmatched, key),
  	.head_offset = offsetof(struct mlxsw_sp1_ptp_unmatched, ht_node),
  };
  
  struct mlxsw_sp_ptp_clock {
  	struct mlxsw_core *core;
  	spinlock_t lock; /* protect this structure */
  	struct cyclecounter cycles;
  	struct timecounter tc;
  	u32 nominal_c_mult;
  	struct ptp_clock *ptp;
  	struct ptp_clock_info ptp_info;
  	unsigned long overflow_period;
  	struct delayed_work overflow_work;
  };
  
  static u64 __mlxsw_sp1_ptp_read_frc(struct mlxsw_sp_ptp_clock *clock,
  				    struct ptp_system_timestamp *sts)
  {
  	struct mlxsw_core *mlxsw_core = clock->core;
  	u32 frc_h1, frc_h2, frc_l;
  
  	frc_h1 = mlxsw_core_read_frc_h(mlxsw_core);
  	ptp_read_system_prets(sts);
  	frc_l = mlxsw_core_read_frc_l(mlxsw_core);
  	ptp_read_system_postts(sts);
  	frc_h2 = mlxsw_core_read_frc_h(mlxsw_core);
  
  	if (frc_h1 != frc_h2) {
  		/* wrap around */
  		ptp_read_system_prets(sts);
  		frc_l = mlxsw_core_read_frc_l(mlxsw_core);
  		ptp_read_system_postts(sts);
  	}
  
  	return (u64) frc_l | (u64) frc_h2 << 32;
  }
  
  static u64 mlxsw_sp1_ptp_read_frc(const struct cyclecounter *cc)
  {
  	struct mlxsw_sp_ptp_clock *clock =
  		container_of(cc, struct mlxsw_sp_ptp_clock, cycles);
  
  	return __mlxsw_sp1_ptp_read_frc(clock, NULL) & cc->mask;
  }
  
  static int
  mlxsw_sp1_ptp_phc_adjfreq(struct mlxsw_sp_ptp_clock *clock, int freq_adj)
  {
  	struct mlxsw_core *mlxsw_core = clock->core;
  	char mtutc_pl[MLXSW_REG_MTUTC_LEN];
  
  	mlxsw_reg_mtutc_pack(mtutc_pl, MLXSW_REG_MTUTC_OPERATION_ADJUST_FREQ,
  			     freq_adj, 0);
  	return mlxsw_reg_write(mlxsw_core, MLXSW_REG(mtutc), mtutc_pl);
  }
  
  static u64 mlxsw_sp1_ptp_ns2cycles(const struct timecounter *tc, u64 nsec)
  {
  	u64 cycles = (u64) nsec;
  
  	cycles <<= tc->cc->shift;
  	cycles = div_u64(cycles, tc->cc->mult);
  
  	return cycles;
  }
  
  static int
  mlxsw_sp1_ptp_phc_settime(struct mlxsw_sp_ptp_clock *clock, u64 nsec)
  {
  	struct mlxsw_core *mlxsw_core = clock->core;
  	u64 next_sec, next_sec_in_nsec, cycles;
  	char mtutc_pl[MLXSW_REG_MTUTC_LEN];
  	char mtpps_pl[MLXSW_REG_MTPPS_LEN];
  	int err;
  
  	next_sec = div_u64(nsec, NSEC_PER_SEC) + 1;
  	next_sec_in_nsec = next_sec * NSEC_PER_SEC;
  
  	spin_lock_bh(&clock->lock);
  	cycles = mlxsw_sp1_ptp_ns2cycles(&clock->tc, next_sec_in_nsec);
  	spin_unlock_bh(&clock->lock);
  
  	mlxsw_reg_mtpps_vpin_pack(mtpps_pl, cycles);
  	err = mlxsw_reg_write(mlxsw_core, MLXSW_REG(mtpps), mtpps_pl);
  	if (err)
  		return err;
  
  	mlxsw_reg_mtutc_pack(mtutc_pl,
  			     MLXSW_REG_MTUTC_OPERATION_SET_TIME_AT_NEXT_SEC,
  			     0, next_sec);
  	return mlxsw_reg_write(mlxsw_core, MLXSW_REG(mtutc), mtutc_pl);
  }
  
  static int mlxsw_sp1_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
  {
  	struct mlxsw_sp_ptp_clock *clock =
  		container_of(ptp, struct mlxsw_sp_ptp_clock, ptp_info);
  	int neg_adj = 0;
  	u32 diff;
  	u64 adj;
  	s32 ppb;
  
  	ppb = scaled_ppm_to_ppb(scaled_ppm);
  
  	if (ppb < 0) {
  		neg_adj = 1;
  		ppb = -ppb;
  	}
  
  	adj = clock->nominal_c_mult;
  	adj *= ppb;
  	diff = div_u64(adj, NSEC_PER_SEC);
  
  	spin_lock_bh(&clock->lock);
  	timecounter_read(&clock->tc);
  	clock->cycles.mult = neg_adj ? clock->nominal_c_mult - diff :
  				       clock->nominal_c_mult + diff;
  	spin_unlock_bh(&clock->lock);
  
  	return mlxsw_sp1_ptp_phc_adjfreq(clock, neg_adj ? -ppb : ppb);
  }
  
  static int mlxsw_sp1_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
  {
  	struct mlxsw_sp_ptp_clock *clock =
  		container_of(ptp, struct mlxsw_sp_ptp_clock, ptp_info);
  	u64 nsec;
  
  	spin_lock_bh(&clock->lock);
  	timecounter_adjtime(&clock->tc, delta);
  	nsec = timecounter_read(&clock->tc);
  	spin_unlock_bh(&clock->lock);
  
  	return mlxsw_sp1_ptp_phc_settime(clock, nsec);
  }
  
  static int mlxsw_sp1_ptp_gettimex(struct ptp_clock_info *ptp,
  				  struct timespec64 *ts,
  				  struct ptp_system_timestamp *sts)
  {
  	struct mlxsw_sp_ptp_clock *clock =
  		container_of(ptp, struct mlxsw_sp_ptp_clock, ptp_info);
  	u64 cycles, nsec;
  
  	spin_lock_bh(&clock->lock);
  	cycles = __mlxsw_sp1_ptp_read_frc(clock, sts);
  	nsec = timecounter_cyc2time(&clock->tc, cycles);
  	spin_unlock_bh(&clock->lock);
  
  	*ts = ns_to_timespec64(nsec);
  
  	return 0;
  }
  
  static int mlxsw_sp1_ptp_settime(struct ptp_clock_info *ptp,
  				 const struct timespec64 *ts)
  {
  	struct mlxsw_sp_ptp_clock *clock =
  		container_of(ptp, struct mlxsw_sp_ptp_clock, ptp_info);
  	u64 nsec = timespec64_to_ns(ts);
  
  	spin_lock_bh(&clock->lock);
  	timecounter_init(&clock->tc, &clock->cycles, nsec);
  	nsec = timecounter_read(&clock->tc);
  	spin_unlock_bh(&clock->lock);
  
  	return mlxsw_sp1_ptp_phc_settime(clock, nsec);
  }
  
  static const struct ptp_clock_info mlxsw_sp1_ptp_clock_info = {
  	.owner		= THIS_MODULE,
  	.name		= "mlxsw_sp_clock",
  	.max_adj	= 100000000,
  	.adjfine	= mlxsw_sp1_ptp_adjfine,
  	.adjtime	= mlxsw_sp1_ptp_adjtime,
  	.gettimex64	= mlxsw_sp1_ptp_gettimex,
  	.settime64	= mlxsw_sp1_ptp_settime,
  };
  
  static void mlxsw_sp1_ptp_clock_overflow(struct work_struct *work)
  {
  	struct delayed_work *dwork = to_delayed_work(work);
  	struct mlxsw_sp_ptp_clock *clock;
  
  	clock = container_of(dwork, struct mlxsw_sp_ptp_clock, overflow_work);
  
  	spin_lock_bh(&clock->lock);
  	timecounter_read(&clock->tc);
  	spin_unlock_bh(&clock->lock);
  	mlxsw_core_schedule_dw(&clock->overflow_work, clock->overflow_period);
  }
  
  struct mlxsw_sp_ptp_clock *
  mlxsw_sp1_ptp_clock_init(struct mlxsw_sp *mlxsw_sp, struct device *dev)
  {
  	u64 overflow_cycles, nsec, frac = 0;
  	struct mlxsw_sp_ptp_clock *clock;
  	int err;
  
  	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
  	if (!clock)
  		return ERR_PTR(-ENOMEM);
  
  	spin_lock_init(&clock->lock);
  	clock->cycles.read = mlxsw_sp1_ptp_read_frc;
  	clock->cycles.shift = MLXSW_SP1_PTP_CLOCK_CYCLES_SHIFT;
  	clock->cycles.mult = clocksource_khz2mult(MLXSW_SP1_PTP_CLOCK_FREQ_KHZ,
  						  clock->cycles.shift);
  	clock->nominal_c_mult = clock->cycles.mult;
  	clock->cycles.mask = CLOCKSOURCE_MASK(MLXSW_SP1_PTP_CLOCK_MASK);
  	clock->core = mlxsw_sp->core;
  
  	timecounter_init(&clock->tc, &clock->cycles,
  			 ktime_to_ns(ktime_get_real()));
  
  	/* Calculate period in seconds to call the overflow watchdog - to make
  	 * sure counter is checked at least twice every wrap around.
  	 * The period is calculated as the minimum between max HW cycles count
  	 * (The clock source mask) and max amount of cycles that can be
  	 * multiplied by clock multiplier where the result doesn't exceed
  	 * 64bits.
  	 */
  	overflow_cycles = div64_u64(~0ULL >> 1, clock->cycles.mult);
  	overflow_cycles = min(overflow_cycles, div_u64(clock->cycles.mask, 3));
  
  	nsec = cyclecounter_cyc2ns(&clock->cycles, overflow_cycles, 0, &frac);
  	clock->overflow_period = nsecs_to_jiffies(nsec);
  
  	INIT_DELAYED_WORK(&clock->overflow_work, mlxsw_sp1_ptp_clock_overflow);
  	mlxsw_core_schedule_dw(&clock->overflow_work, 0);
  
  	clock->ptp_info = mlxsw_sp1_ptp_clock_info;
  	clock->ptp = ptp_clock_register(&clock->ptp_info, dev);
  	if (IS_ERR(clock->ptp)) {
  		err = PTR_ERR(clock->ptp);
  		dev_err(dev, "ptp_clock_register failed %d\n", err);
  		goto err_ptp_clock_register;
  	}
  
  	return clock;
  
  err_ptp_clock_register:
  	cancel_delayed_work_sync(&clock->overflow_work);
  	kfree(clock);
  	return ERR_PTR(err);
  }
  
  void mlxsw_sp1_ptp_clock_fini(struct mlxsw_sp_ptp_clock *clock)
  {
  	ptp_clock_unregister(clock->ptp);
  	cancel_delayed_work_sync(&clock->overflow_work);
  	kfree(clock);
  }
  
  static int mlxsw_sp_ptp_parse(struct sk_buff *skb,
  			      u8 *p_domain_number,
  			      u8 *p_message_type,
  			      u16 *p_sequence_id)
  {
  	unsigned int ptp_class;
  	struct ptp_header *hdr;
  
  	ptp_class = ptp_classify_raw(skb);
  
  	switch (ptp_class & PTP_CLASS_VMASK) {
  	case PTP_CLASS_V1:
  	case PTP_CLASS_V2:
  		break;
  	default:
  		return -ERANGE;
  	}
  
  	hdr = ptp_parse_header(skb, ptp_class);
  	if (!hdr)
  		return -EINVAL;
  
  	*p_message_type	 = ptp_get_msgtype(hdr, ptp_class);
  	*p_domain_number = hdr->domain_number;
  	*p_sequence_id	 = be16_to_cpu(hdr->sequence_id);
  
  	return 0;
  }
  
  /* Returns NULL on successful insertion, a pointer on conflict, or an ERR_PTR on
   * error.
   */
  static int
  mlxsw_sp1_ptp_unmatched_save(struct mlxsw_sp *mlxsw_sp,
  			     struct mlxsw_sp1_ptp_key key,
  			     struct sk_buff *skb,
  			     u64 timestamp)
  {
  	int cycles = MLXSW_SP1_PTP_HT_GC_TIMEOUT / MLXSW_SP1_PTP_HT_GC_INTERVAL;
  	struct mlxsw_sp_ptp_state *ptp_state = mlxsw_sp->ptp_state;
  	struct mlxsw_sp1_ptp_unmatched *unmatched;
  	int err;
  
  	unmatched = kzalloc(sizeof(*unmatched), GFP_ATOMIC);
  	if (!unmatched)
  		return -ENOMEM;
  
  	unmatched->key = key;
  	unmatched->skb = skb;
  	unmatched->timestamp = timestamp;
  	unmatched->gc_cycle = mlxsw_sp->ptp_state->gc_cycle + cycles;
  
  	err = rhltable_insert(&ptp_state->unmatched_ht, &unmatched->ht_node,
  			      mlxsw_sp1_ptp_unmatched_ht_params);
  	if (err)
  		kfree(unmatched);
  
  	return err;
  }
  
  static struct mlxsw_sp1_ptp_unmatched *
  mlxsw_sp1_ptp_unmatched_lookup(struct mlxsw_sp *mlxsw_sp,
  			       struct mlxsw_sp1_ptp_key key, int *p_length)
  {
  	struct mlxsw_sp1_ptp_unmatched *unmatched, *last = NULL;
  	struct rhlist_head *tmp, *list;
  	int length = 0;
  
  	list = rhltable_lookup(&mlxsw_sp->ptp_state->unmatched_ht, &key,
  			       mlxsw_sp1_ptp_unmatched_ht_params);
  	rhl_for_each_entry_rcu(unmatched, tmp, list, ht_node) {
  		last = unmatched;
  		length++;
  	}
  
  	*p_length = length;
  	return last;
  }
  
  static int
  mlxsw_sp1_ptp_unmatched_remove(struct mlxsw_sp *mlxsw_sp,
  			       struct mlxsw_sp1_ptp_unmatched *unmatched)
  {
  	return rhltable_remove(&mlxsw_sp->ptp_state->unmatched_ht,
  			       &unmatched->ht_node,
  			       mlxsw_sp1_ptp_unmatched_ht_params);
  }
  
  /* This function is called in the following scenarios:
   *
   * 1) When a packet is matched with its timestamp.
   * 2) In several situation when it is necessary to immediately pass on
   *    an SKB without a timestamp.
   * 3) From GC indirectly through mlxsw_sp1_ptp_unmatched_finish().
   *    This case is similar to 2) above.
   */
  static void mlxsw_sp1_ptp_packet_finish(struct mlxsw_sp *mlxsw_sp,
  					struct sk_buff *skb, u16 local_port,
  					bool ingress,
  					struct skb_shared_hwtstamps *hwtstamps)
  {
  	struct mlxsw_sp_port *mlxsw_sp_port;
  
  	/* Between capturing the packet and finishing it, there is a window of
  	 * opportunity for the originating port to go away (e.g. due to a
  	 * split). Also make sure the SKB device reference is still valid.
  	 */
  	mlxsw_sp_port = mlxsw_sp->ports[local_port];
  	if (!(mlxsw_sp_port && (!skb->dev || skb->dev == mlxsw_sp_port->dev))) {
  		dev_kfree_skb_any(skb);
  		return;
  	}
  
  	if (ingress) {
  		if (hwtstamps)
  			*skb_hwtstamps(skb) = *hwtstamps;
  		mlxsw_sp_rx_listener_no_mark_func(skb, local_port, mlxsw_sp);
  	} else {
  		/* skb_tstamp_tx() allows hwtstamps to be NULL. */
  		skb_tstamp_tx(skb, hwtstamps);
  		dev_kfree_skb_any(skb);
  	}
  }
  
  static void mlxsw_sp1_packet_timestamp(struct mlxsw_sp *mlxsw_sp,
  				       struct mlxsw_sp1_ptp_key key,
  				       struct sk_buff *skb,
  				       u64 timestamp)
  {
  	struct skb_shared_hwtstamps hwtstamps;
  	u64 nsec;
  
  	spin_lock_bh(&mlxsw_sp->clock->lock);
  	nsec = timecounter_cyc2time(&mlxsw_sp->clock->tc, timestamp);
  	spin_unlock_bh(&mlxsw_sp->clock->lock);
  
  	hwtstamps.hwtstamp = ns_to_ktime(nsec);
  	mlxsw_sp1_ptp_packet_finish(mlxsw_sp, skb,
  				    key.local_port, key.ingress, &hwtstamps);
  }
  
  static void
  mlxsw_sp1_ptp_unmatched_finish(struct mlxsw_sp *mlxsw_sp,
  			       struct mlxsw_sp1_ptp_unmatched *unmatched)
  {
  	if (unmatched->skb && unmatched->timestamp)
  		mlxsw_sp1_packet_timestamp(mlxsw_sp, unmatched->key,
  					   unmatched->skb,
  					   unmatched->timestamp);
  	else if (unmatched->skb)
  		mlxsw_sp1_ptp_packet_finish(mlxsw_sp, unmatched->skb,
  					    unmatched->key.local_port,
  					    unmatched->key.ingress, NULL);
  	kfree_rcu(unmatched, rcu);
  }
  
  static void mlxsw_sp1_ptp_unmatched_free_fn(void *ptr, void *arg)
  {
  	struct mlxsw_sp1_ptp_unmatched *unmatched = ptr;
  
  	/* This is invoked at a point where the ports are gone already. Nothing
  	 * to do with whatever is left in the HT but to free it.
  	 */
  	if (unmatched->skb)
  		dev_kfree_skb_any(unmatched->skb);
  	kfree_rcu(unmatched, rcu);
  }
  
  static void mlxsw_sp1_ptp_got_piece(struct mlxsw_sp *mlxsw_sp,
  				    struct mlxsw_sp1_ptp_key key,
  				    struct sk_buff *skb, u64 timestamp)
  {
  	struct mlxsw_sp1_ptp_unmatched *unmatched;
  	int length;
  	int err;
  
  	rcu_read_lock();
  
  	spin_lock(&mlxsw_sp->ptp_state->unmatched_lock);
  
  	unmatched = mlxsw_sp1_ptp_unmatched_lookup(mlxsw_sp, key, &length);
  	if (skb && unmatched && unmatched->timestamp) {
  		unmatched->skb = skb;
  	} else if (timestamp && unmatched && unmatched->skb) {
  		unmatched->timestamp = timestamp;
  	} else {
  		/* Either there is no entry to match, or one that is there is
  		 * incompatible.
  		 */
  		if (length < 100)
  			err = mlxsw_sp1_ptp_unmatched_save(mlxsw_sp, key,
  							   skb, timestamp);
  		else
  			err = -E2BIG;
  		if (err && skb)
  			mlxsw_sp1_ptp_packet_finish(mlxsw_sp, skb,
  						    key.local_port,
  						    key.ingress, NULL);
  		unmatched = NULL;
  	}
  
  	if (unmatched) {
  		err = mlxsw_sp1_ptp_unmatched_remove(mlxsw_sp, unmatched);
  		WARN_ON_ONCE(err);
  	}
  
  	spin_unlock(&mlxsw_sp->ptp_state->unmatched_lock);
  
  	if (unmatched)
  		mlxsw_sp1_ptp_unmatched_finish(mlxsw_sp, unmatched);
  
  	rcu_read_unlock();
  }
  
  static void mlxsw_sp1_ptp_got_packet(struct mlxsw_sp *mlxsw_sp,
  				     struct sk_buff *skb, u16 local_port,
  				     bool ingress)
  {
  	struct mlxsw_sp_port *mlxsw_sp_port;
  	struct mlxsw_sp1_ptp_key key;
  	u8 types;
  	int err;
  
  	mlxsw_sp_port = mlxsw_sp->ports[local_port];
  	if (!mlxsw_sp_port)
  		goto immediate;
  
  	types = ingress ? mlxsw_sp_port->ptp.ing_types :
  			  mlxsw_sp_port->ptp.egr_types;
  	if (!types)
  		goto immediate;
  
  	memset(&key, 0, sizeof(key));
  	key.local_port = local_port;
  	key.ingress = ingress;
  
  	err = mlxsw_sp_ptp_parse(skb, &key.domain_number, &key.message_type,
  				 &key.sequence_id);
  	if (err)
  		goto immediate;
  
  	/* For packets whose timestamping was not enabled on this port, don't
  	 * bother trying to match the timestamp.
  	 */
  	if (!((1 << key.message_type) & types))
  		goto immediate;
  
  	mlxsw_sp1_ptp_got_piece(mlxsw_sp, key, skb, 0);
  	return;
  
  immediate:
  	mlxsw_sp1_ptp_packet_finish(mlxsw_sp, skb, local_port, ingress, NULL);
  }
  
  void mlxsw_sp1_ptp_got_timestamp(struct mlxsw_sp *mlxsw_sp, bool ingress,
  				 u16 local_port, u8 message_type,
  				 u8 domain_number, u16 sequence_id,
  				 u64 timestamp)
  {
  	struct mlxsw_sp_port *mlxsw_sp_port;
  	struct mlxsw_sp1_ptp_key key;
  	u8 types;
  
  	if (WARN_ON_ONCE(!mlxsw_sp_local_port_is_valid(mlxsw_sp, local_port)))
  		return;
  	mlxsw_sp_port = mlxsw_sp->ports[local_port];
  	if (!mlxsw_sp_port)
  		return;
  
  	types = ingress ? mlxsw_sp_port->ptp.ing_types :
  			  mlxsw_sp_port->ptp.egr_types;
  
  	/* For message types whose timestamping was not enabled on this port,
  	 * don't bother with the timestamp.
  	 */
  	if (!((1 << message_type) & types))
  		return;
  
  	memset(&key, 0, sizeof(key));
  	key.local_port = local_port;
  	key.domain_number = domain_number;
  	key.message_type = message_type;
  	key.sequence_id = sequence_id;
  	key.ingress = ingress;
  
  	mlxsw_sp1_ptp_got_piece(mlxsw_sp, key, NULL, timestamp);
  }
  
  void mlxsw_sp1_ptp_receive(struct mlxsw_sp *mlxsw_sp, struct sk_buff *skb,
  			   u16 local_port)
  {
  	skb_reset_mac_header(skb);
  	mlxsw_sp1_ptp_got_packet(mlxsw_sp, skb, local_port, true);
  }
  
  void mlxsw_sp1_ptp_transmitted(struct mlxsw_sp *mlxsw_sp,
  			       struct sk_buff *skb, u16 local_port)
  {
  	mlxsw_sp1_ptp_got_packet(mlxsw_sp, skb, local_port, false);
  }
  
  static void
  mlxsw_sp1_ptp_ht_gc_collect(struct mlxsw_sp_ptp_state *ptp_state,
  			    struct mlxsw_sp1_ptp_unmatched *unmatched)
  {
  	struct mlxsw_sp_ptp_port_dir_stats *stats;
  	struct mlxsw_sp_port *mlxsw_sp_port;
  	int err;
  
  	/* If an unmatched entry has an SKB, it has to be handed over to the
  	 * networking stack. This is usually done from a trap handler, which is
  	 * invoked in a softirq context. Here we are going to do it in process
  	 * context. If that were to be interrupted by a softirq, it could cause
  	 * a deadlock when an attempt is made to take an already-taken lock
  	 * somewhere along the sending path. Disable softirqs to prevent this.
  	 */
  	local_bh_disable();
  
  	spin_lock(&ptp_state->unmatched_lock);
  	err = rhltable_remove(&ptp_state->unmatched_ht, &unmatched->ht_node,
  			      mlxsw_sp1_ptp_unmatched_ht_params);
  	spin_unlock(&ptp_state->unmatched_lock);
  
  	if (err)
  		/* The packet was matched with timestamp during the walk. */
  		goto out;
  
  	mlxsw_sp_port = ptp_state->mlxsw_sp->ports[unmatched->key.local_port];
  	if (mlxsw_sp_port) {
  		stats = unmatched->key.ingress ?
  			&mlxsw_sp_port->ptp.stats.rx_gcd :
  			&mlxsw_sp_port->ptp.stats.tx_gcd;
  		if (unmatched->skb)
  			stats->packets++;
  		else
  			stats->timestamps++;
  	}
  
  	/* mlxsw_sp1_ptp_unmatched_finish() invokes netif_receive_skb(). While
  	 * the comment at that function states that it can only be called in
  	 * soft IRQ context, this pattern of local_bh_disable() +
  	 * netif_receive_skb(), in process context, is seen elsewhere in the
  	 * kernel, notably in pktgen.
  	 */
  	mlxsw_sp1_ptp_unmatched_finish(ptp_state->mlxsw_sp, unmatched);
  
  out:
  	local_bh_enable();
  }
  
  static void mlxsw_sp1_ptp_ht_gc(struct work_struct *work)
  {
  	struct delayed_work *dwork = to_delayed_work(work);
  	struct mlxsw_sp1_ptp_unmatched *unmatched;
  	struct mlxsw_sp_ptp_state *ptp_state;
  	struct rhashtable_iter iter;
  	u32 gc_cycle;
  	void *obj;
  
  	ptp_state = container_of(dwork, struct mlxsw_sp_ptp_state, ht_gc_dw);
  	gc_cycle = ptp_state->gc_cycle++;
  
  	rhltable_walk_enter(&ptp_state->unmatched_ht, &iter);
  	rhashtable_walk_start(&iter);
  	while ((obj = rhashtable_walk_next(&iter))) {
  		if (IS_ERR(obj))
  			continue;
  
  		unmatched = obj;
  		if (unmatched->gc_cycle <= gc_cycle)
  			mlxsw_sp1_ptp_ht_gc_collect(ptp_state, unmatched);
  	}
  	rhashtable_walk_stop(&iter);
  	rhashtable_walk_exit(&iter);
  
  	mlxsw_core_schedule_dw(&ptp_state->ht_gc_dw,
  			       MLXSW_SP1_PTP_HT_GC_INTERVAL);
  }
  
  static int mlxsw_sp_ptp_mtptpt_set(struct mlxsw_sp *mlxsw_sp,
  				   enum mlxsw_reg_mtptpt_trap_id trap_id,
  				   u16 message_type)
  {
  	char mtptpt_pl[MLXSW_REG_MTPTPT_LEN];
  
  	mlxsw_reg_mtptptp_pack(mtptpt_pl, trap_id, message_type);
  	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mtptpt), mtptpt_pl);
  }
  
  static int mlxsw_sp1_ptp_set_fifo_clr_on_trap(struct mlxsw_sp *mlxsw_sp,
  					      bool clr)
  {
  	char mogcr_pl[MLXSW_REG_MOGCR_LEN] = {0};
  	int err;
  
  	err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(mogcr), mogcr_pl);
  	if (err)
  		return err;
  
  	mlxsw_reg_mogcr_ptp_iftc_set(mogcr_pl, clr);
  	mlxsw_reg_mogcr_ptp_eftc_set(mogcr_pl, clr);
  	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mogcr), mogcr_pl);
  }
  
  static int mlxsw_sp1_ptp_mtpppc_set(struct mlxsw_sp *mlxsw_sp,
  				    u16 ing_types, u16 egr_types)
  {
  	char mtpppc_pl[MLXSW_REG_MTPPPC_LEN];
  
  	mlxsw_reg_mtpppc_pack(mtpppc_pl, ing_types, egr_types);
  	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mtpppc), mtpppc_pl);
  }
  
  struct mlxsw_sp1_ptp_shaper_params {
  	u32 ethtool_speed;
  	enum mlxsw_reg_qpsc_port_speed port_speed;
  	u8 shaper_time_exp;
  	u8 shaper_time_mantissa;
  	u8 shaper_inc;
  	u8 shaper_bs;
  	u8 port_to_shaper_credits;
  	int ing_timestamp_inc;
  	int egr_timestamp_inc;
  };
  
  static const struct mlxsw_sp1_ptp_shaper_params
  mlxsw_sp1_ptp_shaper_params[] = {
  	{
  		.ethtool_speed		= SPEED_100,
  		.port_speed		= MLXSW_REG_QPSC_PORT_SPEED_100M,
  		.shaper_time_exp	= 4,
  		.shaper_time_mantissa	= 12,
  		.shaper_inc		= 9,
  		.shaper_bs		= 1,
  		.port_to_shaper_credits	= 1,
  		.ing_timestamp_inc	= -313,
  		.egr_timestamp_inc	= 313,
  	},
  	{
  		.ethtool_speed		= SPEED_1000,
  		.port_speed		= MLXSW_REG_QPSC_PORT_SPEED_1G,
  		.shaper_time_exp	= 0,
  		.shaper_time_mantissa	= 12,
  		.shaper_inc		= 6,
  		.shaper_bs		= 0,
  		.port_to_shaper_credits	= 1,
  		.ing_timestamp_inc	= -35,
  		.egr_timestamp_inc	= 35,
  	},
  	{
  		.ethtool_speed		= SPEED_10000,
  		.port_speed		= MLXSW_REG_QPSC_PORT_SPEED_10G,
  		.shaper_time_exp	= 0,
  		.shaper_time_mantissa	= 2,
  		.shaper_inc		= 14,
  		.shaper_bs		= 1,
  		.port_to_shaper_credits	= 1,
  		.ing_timestamp_inc	= -11,
  		.egr_timestamp_inc	= 11,
  	},
  	{
  		.ethtool_speed		= SPEED_25000,
  		.port_speed		= MLXSW_REG_QPSC_PORT_SPEED_25G,
  		.shaper_time_exp	= 0,
  		.shaper_time_mantissa	= 0,
  		.shaper_inc		= 11,
  		.shaper_bs		= 1,
  		.port_to_shaper_credits	= 1,
  		.ing_timestamp_inc	= -14,
  		.egr_timestamp_inc	= 14,
  	},
  };
  
  #define MLXSW_SP1_PTP_SHAPER_PARAMS_LEN ARRAY_SIZE(mlxsw_sp1_ptp_shaper_params)
  
  static int mlxsw_sp1_ptp_shaper_params_set(struct mlxsw_sp *mlxsw_sp)
  {
  	const struct mlxsw_sp1_ptp_shaper_params *params;
  	char qpsc_pl[MLXSW_REG_QPSC_LEN];
  	int i, err;
  
  	for (i = 0; i < MLXSW_SP1_PTP_SHAPER_PARAMS_LEN; i++) {
  		params = &mlxsw_sp1_ptp_shaper_params[i];
  		mlxsw_reg_qpsc_pack(qpsc_pl, params->port_speed,
  				    params->shaper_time_exp,
  				    params->shaper_time_mantissa,
  				    params->shaper_inc, params->shaper_bs,
  				    params->port_to_shaper_credits,
  				    params->ing_timestamp_inc,
  				    params->egr_timestamp_inc);
  		err = mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(qpsc), qpsc_pl);
  		if (err)
  			return err;
  	}
  
  	return 0;
  }
  
  struct mlxsw_sp_ptp_state *mlxsw_sp1_ptp_init(struct mlxsw_sp *mlxsw_sp)
  {
  	struct mlxsw_sp_ptp_state *ptp_state;
  	u16 message_type;
  	int err;
  
  	err = mlxsw_sp1_ptp_shaper_params_set(mlxsw_sp);
  	if (err)
  		return ERR_PTR(err);
  
  	ptp_state = kzalloc(sizeof(*ptp_state), GFP_KERNEL);
  	if (!ptp_state)
  		return ERR_PTR(-ENOMEM);
  	ptp_state->mlxsw_sp = mlxsw_sp;
  
  	spin_lock_init(&ptp_state->unmatched_lock);
  
  	err = rhltable_init(&ptp_state->unmatched_ht,
  			    &mlxsw_sp1_ptp_unmatched_ht_params);
  	if (err)
  		goto err_hashtable_init;
  
  	/* Delive these message types as PTP0. */
  	message_type = BIT(PTP_MSGTYPE_SYNC) |
  		       BIT(PTP_MSGTYPE_DELAY_REQ) |
  		       BIT(PTP_MSGTYPE_PDELAY_REQ) |
  		       BIT(PTP_MSGTYPE_PDELAY_RESP);
  	err = mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP0,
  				      message_type);
  	if (err)
  		goto err_mtptpt_set;
  
  	/* Everything else is PTP1. */
  	message_type = ~message_type;
  	err = mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP1,
  				      message_type);
  	if (err)
  		goto err_mtptpt1_set;
  
  	err = mlxsw_sp1_ptp_set_fifo_clr_on_trap(mlxsw_sp, true);
  	if (err)
  		goto err_fifo_clr;
  
  	INIT_DELAYED_WORK(&ptp_state->ht_gc_dw, mlxsw_sp1_ptp_ht_gc);
  	mlxsw_core_schedule_dw(&ptp_state->ht_gc_dw,
  			       MLXSW_SP1_PTP_HT_GC_INTERVAL);
  	return ptp_state;
  
  err_fifo_clr:
  	mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP1, 0);
  err_mtptpt1_set:
  	mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP0, 0);
  err_mtptpt_set:
  	rhltable_destroy(&ptp_state->unmatched_ht);
  err_hashtable_init:
  	kfree(ptp_state);
  	return ERR_PTR(err);
  }
  
  void mlxsw_sp1_ptp_fini(struct mlxsw_sp_ptp_state *ptp_state)
  {
  	struct mlxsw_sp *mlxsw_sp = ptp_state->mlxsw_sp;
  
  	cancel_delayed_work_sync(&ptp_state->ht_gc_dw);
  	mlxsw_sp1_ptp_mtpppc_set(mlxsw_sp, 0, 0);
  	mlxsw_sp1_ptp_set_fifo_clr_on_trap(mlxsw_sp, false);
  	mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP1, 0);
  	mlxsw_sp_ptp_mtptpt_set(mlxsw_sp, MLXSW_REG_MTPTPT_TRAP_ID_PTP0, 0);
  	rhltable_free_and_destroy(&ptp_state->unmatched_ht,
  				  &mlxsw_sp1_ptp_unmatched_free_fn, NULL);
  	kfree(ptp_state);
  }
  
  int mlxsw_sp1_ptp_hwtstamp_get(struct mlxsw_sp_port *mlxsw_sp_port,
  			       struct hwtstamp_config *config)
  {
  	*config = mlxsw_sp_port->ptp.hwtstamp_config;
  	return 0;
  }
  
  static int mlxsw_sp_ptp_get_message_types(const struct hwtstamp_config *config,
  					  u16 *p_ing_types, u16 *p_egr_types,
  					  enum hwtstamp_rx_filters *p_rx_filter)
  {
  	enum hwtstamp_rx_filters rx_filter = config->rx_filter;
  	enum hwtstamp_tx_types tx_type = config->tx_type;
  	u16 ing_types = 0x00;
  	u16 egr_types = 0x00;
  
  	switch (tx_type) {
  	case HWTSTAMP_TX_OFF:
  		egr_types = 0x00;
  		break;
  	case HWTSTAMP_TX_ON:
  		egr_types = 0xff;
  		break;
  	case HWTSTAMP_TX_ONESTEP_SYNC:
  	case HWTSTAMP_TX_ONESTEP_P2P:
  		return -ERANGE;
  	default:
  		return -EINVAL;
  	}
  
  	switch (rx_filter) {
  	case HWTSTAMP_FILTER_NONE:
  		ing_types = 0x00;
  		break;
  	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
  	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
  	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
  	case HWTSTAMP_FILTER_PTP_V2_SYNC:
  		ing_types = 0x01;
  		break;
  	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
  	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
  	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
  	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
  		ing_types = 0x02;
  		break;
  	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
  	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
  	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
  	case HWTSTAMP_FILTER_PTP_V2_EVENT:
  		ing_types = 0x0f;
  		break;
  	case HWTSTAMP_FILTER_ALL:
  		ing_types = 0xff;
  		break;
  	case HWTSTAMP_FILTER_SOME:
  	case HWTSTAMP_FILTER_NTP_ALL:
  		return -ERANGE;
  	default:
  		return -EINVAL;
  	}
  
  	*p_ing_types = ing_types;
  	*p_egr_types = egr_types;
  	*p_rx_filter = rx_filter;
  	return 0;
  }
  
  static int mlxsw_sp1_ptp_mtpppc_update(struct mlxsw_sp_port *mlxsw_sp_port,
  				       u16 ing_types, u16 egr_types)
  {
  	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
  	struct mlxsw_sp_port *tmp;
  	u16 orig_ing_types = 0;
  	u16 orig_egr_types = 0;
  	int err;
  	int i;
  
  	/* MTPPPC configures timestamping globally, not per port. Find the
  	 * configuration that contains all configured timestamping requests.
  	 */
  	for (i = 1; i < mlxsw_core_max_ports(mlxsw_sp->core); i++) {
  		tmp = mlxsw_sp->ports[i];
  		if (tmp) {
  			orig_ing_types |= tmp->ptp.ing_types;
  			orig_egr_types |= tmp->ptp.egr_types;
  		}
  		if (tmp && tmp != mlxsw_sp_port) {
  			ing_types |= tmp->ptp.ing_types;
  			egr_types |= tmp->ptp.egr_types;
  		}
  	}
  
  	if ((ing_types || egr_types) && !(orig_ing_types || orig_egr_types)) {
  		err = mlxsw_sp_parsing_depth_inc(mlxsw_sp);
  		if (err) {
  			netdev_err(mlxsw_sp_port->dev, "Failed to increase parsing depth");
  			return err;
  		}
  	}
  	if (!(ing_types || egr_types) && (orig_ing_types || orig_egr_types))
  		mlxsw_sp_parsing_depth_dec(mlxsw_sp);
  
  	return mlxsw_sp1_ptp_mtpppc_set(mlxsw_sp_port->mlxsw_sp,
  				       ing_types, egr_types);
  }
  
  static bool mlxsw_sp1_ptp_hwtstamp_enabled(struct mlxsw_sp_port *mlxsw_sp_port)
  {
  	return mlxsw_sp_port->ptp.ing_types || mlxsw_sp_port->ptp.egr_types;
  }
  
  static int
  mlxsw_sp1_ptp_port_shaper_set(struct mlxsw_sp_port *mlxsw_sp_port, bool enable)
  {
  	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
  	char qeec_pl[MLXSW_REG_QEEC_LEN];
  
  	mlxsw_reg_qeec_ptps_pack(qeec_pl, mlxsw_sp_port->local_port, enable);
  	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(qeec), qeec_pl);
  }
  
  static int mlxsw_sp1_ptp_port_shaper_check(struct mlxsw_sp_port *mlxsw_sp_port)
  {
  	bool ptps = false;
  	int err, i;
  	u32 speed;
  
  	if (!mlxsw_sp1_ptp_hwtstamp_enabled(mlxsw_sp_port))
  		return mlxsw_sp1_ptp_port_shaper_set(mlxsw_sp_port, false);
  
  	err = mlxsw_sp_port_speed_get(mlxsw_sp_port, &speed);
  	if (err)
  		return err;
  
  	for (i = 0; i < MLXSW_SP1_PTP_SHAPER_PARAMS_LEN; i++) {
  		if (mlxsw_sp1_ptp_shaper_params[i].ethtool_speed == speed) {
  			ptps = true;
  			break;
  		}
  	}
  
  	return mlxsw_sp1_ptp_port_shaper_set(mlxsw_sp_port, ptps);
  }
  
  void mlxsw_sp1_ptp_shaper_work(struct work_struct *work)
  {
  	struct delayed_work *dwork = to_delayed_work(work);
  	struct mlxsw_sp_port *mlxsw_sp_port;
  	int err;
  
  	mlxsw_sp_port = container_of(dwork, struct mlxsw_sp_port,
  				     ptp.shaper_dw);
  
  	if (!mlxsw_sp1_ptp_hwtstamp_enabled(mlxsw_sp_port))
  		return;
  
  	err = mlxsw_sp1_ptp_port_shaper_check(mlxsw_sp_port);
  	if (err)
  		netdev_err(mlxsw_sp_port->dev, "Failed to set up PTP shaper\n");
  }
  
  int mlxsw_sp1_ptp_hwtstamp_set(struct mlxsw_sp_port *mlxsw_sp_port,
  			       struct hwtstamp_config *config)
  {
  	enum hwtstamp_rx_filters rx_filter;
  	u16 ing_types;
  	u16 egr_types;
  	int err;
  
  	err = mlxsw_sp_ptp_get_message_types(config, &ing_types, &egr_types,
  					     &rx_filter);
  	if (err)
  		return err;
  
  	err = mlxsw_sp1_ptp_mtpppc_update(mlxsw_sp_port, ing_types, egr_types);
  	if (err)
  		return err;
  
  	mlxsw_sp_port->ptp.hwtstamp_config = *config;
  	mlxsw_sp_port->ptp.ing_types = ing_types;
  	mlxsw_sp_port->ptp.egr_types = egr_types;
  
  	err = mlxsw_sp1_ptp_port_shaper_check(mlxsw_sp_port);
  	if (err)
  		return err;
  
  	/* Notify the ioctl caller what we are actually timestamping. */
  	config->rx_filter = rx_filter;
  
  	return 0;
  }
  
  int mlxsw_sp1_ptp_get_ts_info(struct mlxsw_sp *mlxsw_sp,
  			      struct ethtool_ts_info *info)
  {
  	info->phc_index = ptp_clock_index(mlxsw_sp->clock->ptp);
  
  	info->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
  				SOF_TIMESTAMPING_RX_HARDWARE |
  				SOF_TIMESTAMPING_RAW_HARDWARE;
  
  	info->tx_types = BIT(HWTSTAMP_TX_OFF) |
  			 BIT(HWTSTAMP_TX_ON);
  
  	info->rx_filters = BIT(HWTSTAMP_FILTER_NONE) |
  			   BIT(HWTSTAMP_FILTER_ALL);
  
  	return 0;
  }
  
  struct mlxsw_sp_ptp_port_stat {
  	char str[ETH_GSTRING_LEN];
  	ptrdiff_t offset;
  };
  
  #define MLXSW_SP_PTP_PORT_STAT(NAME, FIELD)				\
  	{								\
  		.str = NAME,						\
  		.offset = offsetof(struct mlxsw_sp_ptp_port_stats,	\
  				    FIELD),				\
  	}
  
  static const struct mlxsw_sp_ptp_port_stat mlxsw_sp_ptp_port_stats[] = {
  	MLXSW_SP_PTP_PORT_STAT("ptp_rx_gcd_packets",    rx_gcd.packets),
  	MLXSW_SP_PTP_PORT_STAT("ptp_rx_gcd_timestamps", rx_gcd.timestamps),
  	MLXSW_SP_PTP_PORT_STAT("ptp_tx_gcd_packets",    tx_gcd.packets),
  	MLXSW_SP_PTP_PORT_STAT("ptp_tx_gcd_timestamps", tx_gcd.timestamps),
  };
  
  #undef MLXSW_SP_PTP_PORT_STAT
  
  #define MLXSW_SP_PTP_PORT_STATS_LEN \
  	ARRAY_SIZE(mlxsw_sp_ptp_port_stats)
  
  int mlxsw_sp1_get_stats_count(void)
  {
  	return MLXSW_SP_PTP_PORT_STATS_LEN;
  }
  
  void mlxsw_sp1_get_stats_strings(u8 **p)
  {
  	int i;
  
  	for (i = 0; i < MLXSW_SP_PTP_PORT_STATS_LEN; i++) {
  		memcpy(*p, mlxsw_sp_ptp_port_stats[i].str,
  		       ETH_GSTRING_LEN);
  		*p += ETH_GSTRING_LEN;
  	}
  }
  
  void mlxsw_sp1_get_stats(struct mlxsw_sp_port *mlxsw_sp_port,
  			 u64 *data, int data_index)
  {
  	void *stats = &mlxsw_sp_port->ptp.stats;
  	ptrdiff_t offset;
  	int i;
  
  	data += data_index;
  	for (i = 0; i < MLXSW_SP_PTP_PORT_STATS_LEN; i++) {
  		offset = mlxsw_sp_ptp_port_stats[i].offset;
  		*data++ = *(u64 *)(stats + offset);
  	}
  }
  