diff options
Diffstat (limited to 'drivers/net/ethernet/sfc/ptp.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/ptp.c | 1483 |
1 files changed, 1483 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/ptp.c b/drivers/net/ethernet/sfc/ptp.c new file mode 100644 index 000000000000..2b07a4eae07e --- /dev/null +++ b/drivers/net/ethernet/sfc/ptp.c @@ -0,0 +1,1483 @@ +/**************************************************************************** + * Driver for Solarflare Solarstorm network controllers and boards + * Copyright 2011 Solarflare Communications Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation, incorporated herein by reference. + */ + +/* Theory of operation: + * + * PTP support is assisted by firmware running on the MC, which provides + * the hardware timestamping capabilities. Both transmitted and received + * PTP event packets are queued onto internal queues for subsequent processing; + * this is because the MC operations are relatively long and would block + * block NAPI/interrupt operation. + * + * Receive event processing: + * The event contains the packet's UUID and sequence number, together + * with the hardware timestamp. The PTP receive packet queue is searched + * for this UUID/sequence number and, if found, put on a pending queue. + * Packets not matching are delivered without timestamps (MCDI events will + * always arrive after the actual packet). + * It is important for the operation of the PTP protocol that the ordering + * of packets between the event and general port is maintained. + * + * Work queue processing: + * If work waiting, synchronise host/hardware time + * + * Transmit: send packet through MC, which returns the transmission time + * that is converted to an appropriate timestamp. + * + * Receive: the packet's reception time is converted to an appropriate + * timestamp. + */ +#include <linux/ip.h> +#include <linux/udp.h> +#include <linux/time.h> +#include <linux/ktime.h> +#include <linux/module.h> +#include <linux/net_tstamp.h> +#include <linux/pps_kernel.h> +#include <linux/ptp_clock_kernel.h> +#include "net_driver.h" +#include "efx.h" +#include "mcdi.h" +#include "mcdi_pcol.h" +#include "io.h" +#include "regs.h" +#include "nic.h" + +/* Maximum number of events expected to make up a PTP event */ +#define MAX_EVENT_FRAGS 3 + +/* Maximum delay, ms, to begin synchronisation */ +#define MAX_SYNCHRONISE_WAIT_MS 2 + +/* How long, at most, to spend synchronising */ +#define SYNCHRONISE_PERIOD_NS 250000 + +/* How often to update the shared memory time */ +#define SYNCHRONISATION_GRANULARITY_NS 200 + +/* Minimum permitted length of a (corrected) synchronisation time */ +#define MIN_SYNCHRONISATION_NS 120 + +/* Maximum permitted length of a (corrected) synchronisation time */ +#define MAX_SYNCHRONISATION_NS 1000 + +/* How many (MC) receive events that can be queued */ +#define MAX_RECEIVE_EVENTS 8 + +/* Length of (modified) moving average. */ +#define AVERAGE_LENGTH 16 + +/* How long an unmatched event or packet can be held */ +#define PKT_EVENT_LIFETIME_MS 10 + +/* Offsets into PTP packet for identification. These offsets are from the + * start of the IP header, not the MAC header. Note that neither PTP V1 nor + * PTP V2 permit the use of IPV4 options. + */ +#define PTP_DPORT_OFFSET 22 + +#define PTP_V1_VERSION_LENGTH 2 +#define PTP_V1_VERSION_OFFSET 28 + +#define PTP_V1_UUID_LENGTH 6 +#define PTP_V1_UUID_OFFSET 50 + +#define PTP_V1_SEQUENCE_LENGTH 2 +#define PTP_V1_SEQUENCE_OFFSET 58 + +/* The minimum length of a PTP V1 packet for offsets, etc. to be valid: + * includes IP header. + */ +#define PTP_V1_MIN_LENGTH 64 + +#define PTP_V2_VERSION_LENGTH 1 +#define PTP_V2_VERSION_OFFSET 29 + +/* Although PTP V2 UUIDs are comprised a ClockIdentity (8) and PortNumber (2), + * the MC only captures the last six bytes of the clock identity. These values + * reflect those, not the ones used in the standard. The standard permits + * mapping of V1 UUIDs to V2 UUIDs with these same values. + */ +#define PTP_V2_MC_UUID_LENGTH 6 +#define PTP_V2_MC_UUID_OFFSET 50 + +#define PTP_V2_SEQUENCE_LENGTH 2 +#define PTP_V2_SEQUENCE_OFFSET 58 + +/* The minimum length of a PTP V2 packet for offsets, etc. to be valid: + * includes IP header. + */ +#define PTP_V2_MIN_LENGTH 63 + +#define PTP_MIN_LENGTH 63 + +#define PTP_ADDRESS 0xe0000181 /* 224.0.1.129 */ +#define PTP_EVENT_PORT 319 +#define PTP_GENERAL_PORT 320 + +/* Annoyingly the format of the version numbers are different between + * versions 1 and 2 so it isn't possible to simply look for 1 or 2. + */ +#define PTP_VERSION_V1 1 + +#define PTP_VERSION_V2 2 +#define PTP_VERSION_V2_MASK 0x0f + +enum ptp_packet_state { + PTP_PACKET_STATE_UNMATCHED = 0, + PTP_PACKET_STATE_MATCHED, + PTP_PACKET_STATE_TIMED_OUT, + PTP_PACKET_STATE_MATCH_UNWANTED +}; + +/* NIC synchronised with single word of time only comprising + * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds. + */ +#define MC_NANOSECOND_BITS 30 +#define MC_NANOSECOND_MASK ((1 << MC_NANOSECOND_BITS) - 1) +#define MC_SECOND_MASK ((1 << (32 - MC_NANOSECOND_BITS)) - 1) + +/* Maximum parts-per-billion adjustment that is acceptable */ +#define MAX_PPB 1000000 + +/* Number of bits required to hold the above */ +#define MAX_PPB_BITS 20 + +/* Number of extra bits allowed when calculating fractional ns. + * EXTRA_BITS + MC_CMD_PTP_IN_ADJUST_BITS + MAX_PPB_BITS should + * be less than 63. + */ +#define PPB_EXTRA_BITS 2 + +/* Precalculate scale word to avoid long long division at runtime */ +#define PPB_SCALE_WORD ((1LL << (PPB_EXTRA_BITS + MC_CMD_PTP_IN_ADJUST_BITS +\ + MAX_PPB_BITS)) / 1000000000LL) + +#define PTP_SYNC_ATTEMPTS 4 + +/** + * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area. + * @words: UUID and (partial) sequence number + * @expiry: Time after which the packet should be delivered irrespective of + * event arrival. + * @state: The state of the packet - whether it is ready for processing or + * whether that is of no interest. + */ +struct efx_ptp_match { + u32 words[DIV_ROUND_UP(PTP_V1_UUID_LENGTH, 4)]; + unsigned long expiry; + enum ptp_packet_state state; +}; + +/** + * struct efx_ptp_event_rx - A PTP receive event (from MC) + * @seq0: First part of (PTP) UUID + * @seq1: Second part of (PTP) UUID and sequence number + * @hwtimestamp: Event timestamp + */ +struct efx_ptp_event_rx { + struct list_head link; + u32 seq0; + u32 seq1; + ktime_t hwtimestamp; + unsigned long expiry; +}; + +/** + * struct efx_ptp_timeset - Synchronisation between host and MC + * @host_start: Host time immediately before hardware timestamp taken + * @seconds: Hardware timestamp, seconds + * @nanoseconds: Hardware timestamp, nanoseconds + * @host_end: Host time immediately after hardware timestamp taken + * @waitns: Number of nanoseconds between hardware timestamp being read and + * host end time being seen + * @window: Difference of host_end and host_start + * @valid: Whether this timeset is valid + */ +struct efx_ptp_timeset { + u32 host_start; + u32 seconds; + u32 nanoseconds; + u32 host_end; + u32 waitns; + u32 window; /* Derived: end - start, allowing for wrap */ +}; + +/** + * struct efx_ptp_data - Precision Time Protocol (PTP) state + * @channel: The PTP channel + * @rxq: Receive queue (awaiting timestamps) + * @txq: Transmit queue + * @evt_list: List of MC receive events awaiting packets + * @evt_free_list: List of free events + * @evt_lock: Lock for manipulating evt_list and evt_free_list + * @rx_evts: Instantiated events (on evt_list and evt_free_list) + * @workwq: Work queue for processing pending PTP operations + * @work: Work task + * @reset_required: A serious error has occurred and the PTP task needs to be + * reset (disable, enable). + * @rxfilter_event: Receive filter when operating + * @rxfilter_general: Receive filter when operating + * @config: Current timestamp configuration + * @enabled: PTP operation enabled + * @mode: Mode in which PTP operating (PTP version) + * @evt_frags: Partly assembled PTP events + * @evt_frag_idx: Current fragment number + * @evt_code: Last event code + * @start: Address at which MC indicates ready for synchronisation + * @host_time_pps: Host time at last PPS + * @last_sync_ns: Last number of nanoseconds between readings when synchronising + * @base_sync_ns: Number of nanoseconds for last synchronisation. + * @base_sync_valid: Whether base_sync_time is valid. + * @current_adjfreq: Current ppb adjustment. + * @phc_clock: Pointer to registered phc device + * @phc_clock_info: Registration structure for phc device + * @pps_work: pps work task for handling pps events + * @pps_workwq: pps work queue + * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled + * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids + * allocations in main data path). + * @debug_ptp_dir: PTP debugfs directory + * @missed_rx_sync: Number of packets received without syncrhonisation. + * @good_syncs: Number of successful synchronisations. + * @no_time_syncs: Number of synchronisations with no good times. + * @bad_sync_durations: Number of synchronisations with bad durations. + * @bad_syncs: Number of failed synchronisations. + * @last_sync_time: Number of nanoseconds for last synchronisation. + * @sync_timeouts: Number of synchronisation timeouts + * @fast_syncs: Number of synchronisations requiring short delay + * @min_sync_delta: Minimum time between event and synchronisation + * @max_sync_delta: Maximum time between event and synchronisation + * @average_sync_delta: Average time between event and synchronisation. + * Modified moving average. + * @last_sync_delta: Last time between event and synchronisation + * @mc_stats: Context value for MC statistics + * @timeset: Last set of synchronisation statistics. + */ +struct efx_ptp_data { + struct efx_channel *channel; + struct sk_buff_head rxq; + struct sk_buff_head txq; + struct list_head evt_list; + struct list_head evt_free_list; + spinlock_t evt_lock; + struct efx_ptp_event_rx rx_evts[MAX_RECEIVE_EVENTS]; + struct workqueue_struct *workwq; + struct work_struct work; + bool reset_required; + u32 rxfilter_event; + u32 rxfilter_general; + bool rxfilter_installed; + struct hwtstamp_config config; + bool enabled; + unsigned int mode; + efx_qword_t evt_frags[MAX_EVENT_FRAGS]; + int evt_frag_idx; + int evt_code; + struct efx_buffer start; + struct pps_event_time host_time_pps; + unsigned last_sync_ns; + unsigned base_sync_ns; + bool base_sync_valid; + s64 current_adjfreq; + struct ptp_clock *phc_clock; + struct ptp_clock_info phc_clock_info; + struct work_struct pps_work; + struct workqueue_struct *pps_workwq; + bool nic_ts_enabled; + u8 txbuf[ALIGN(MC_CMD_PTP_IN_TRANSMIT_LEN( + MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM), 4)]; + struct efx_ptp_timeset + timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM]; +}; + +static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta); +static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta); +static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts); +static int efx_phc_settime(struct ptp_clock_info *ptp, + const struct timespec *e_ts); +static int efx_phc_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *request, int on); + +/* Enable MCDI PTP support. */ +static int efx_ptp_enable(struct efx_nic *efx) +{ + u8 inbuf[MC_CMD_PTP_IN_ENABLE_LEN]; + + MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE); + MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE, + efx->ptp_data->channel->channel); + MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode); + + return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf), + NULL, 0, NULL); +} + +/* Disable MCDI PTP support. + * + * Note that this function should never rely on the presence of ptp_data - + * may be called before that exists. + */ +static int efx_ptp_disable(struct efx_nic *efx) +{ + u8 inbuf[MC_CMD_PTP_IN_DISABLE_LEN]; + + MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE); + return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf), + NULL, 0, NULL); +} + +static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q) +{ + struct sk_buff *skb; + + while ((skb = skb_dequeue(q))) { + local_bh_disable(); + netif_receive_skb(skb); + local_bh_enable(); + } +} + +static void efx_ptp_handle_no_channel(struct efx_nic *efx) +{ + netif_err(efx, drv, efx->net_dev, + "ERROR: PTP requires MSI-X and 1 additional interrupt" + "vector. PTP disabled\n"); +} + +/* Repeatedly send the host time to the MC which will capture the hardware + * time. + */ +static void efx_ptp_send_times(struct efx_nic *efx, + struct pps_event_time *last_time) +{ + struct pps_event_time now; + struct timespec limit; + struct efx_ptp_data *ptp = efx->ptp_data; + struct timespec start; + int *mc_running = ptp->start.addr; + + pps_get_ts(&now); + start = now.ts_real; + limit = now.ts_real; + timespec_add_ns(&limit, SYNCHRONISE_PERIOD_NS); + + /* Write host time for specified period or until MC is done */ + while ((timespec_compare(&now.ts_real, &limit) < 0) && + ACCESS_ONCE(*mc_running)) { + struct timespec update_time; + unsigned int host_time; + + /* Don't update continuously to avoid saturating the PCIe bus */ + update_time = now.ts_real; + timespec_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS); + do { + pps_get_ts(&now); + } while ((timespec_compare(&now.ts_real, &update_time) < 0) && + ACCESS_ONCE(*mc_running)); + + /* Synchronise NIC with single word of time only */ + host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS | + now.ts_real.tv_nsec); + /* Update host time in NIC memory */ + _efx_writed(efx, cpu_to_le32(host_time), + FR_CZ_MC_TREG_SMEM + MC_SMEM_P0_PTP_TIME_OFST); + } + *last_time = now; +} + +/* Read a timeset from the MC's results and partial process. */ +static void efx_ptp_read_timeset(u8 *data, struct efx_ptp_timeset *timeset) +{ + unsigned start_ns, end_ns; + + timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART); + timeset->seconds = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_SECONDS); + timeset->nanoseconds = MCDI_DWORD(data, + PTP_OUT_SYNCHRONIZE_NANOSECONDS); + timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND), + timeset->waitns = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS); + + /* Ignore seconds */ + start_ns = timeset->host_start & MC_NANOSECOND_MASK; + end_ns = timeset->host_end & MC_NANOSECOND_MASK; + /* Allow for rollover */ + if (end_ns < start_ns) + end_ns += NSEC_PER_SEC; + /* Determine duration of operation */ + timeset->window = end_ns - start_ns; +} + +/* Process times received from MC. + * + * Extract times from returned results, and establish the minimum value + * seen. The minimum value represents the "best" possible time and events + * too much greater than this are rejected - the machine is, perhaps, too + * busy. A number of readings are taken so that, hopefully, at least one good + * synchronisation will be seen in the results. + */ +static int efx_ptp_process_times(struct efx_nic *efx, u8 *synch_buf, + size_t response_length, + const struct pps_event_time *last_time) +{ + unsigned number_readings = (response_length / + MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_LEN); + unsigned i; + unsigned min; + unsigned min_set = 0; + unsigned total; + unsigned ngood = 0; + unsigned last_good = 0; + struct efx_ptp_data *ptp = efx->ptp_data; + bool min_valid = false; + u32 last_sec; + u32 start_sec; + struct timespec delta; + + if (number_readings == 0) + return -EAGAIN; + + /* Find minimum value in this set of results, discarding clearly + * erroneous results. + */ + for (i = 0; i < number_readings; i++) { + efx_ptp_read_timeset(synch_buf, &ptp->timeset[i]); + synch_buf += MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_LEN; + if (ptp->timeset[i].window > SYNCHRONISATION_GRANULARITY_NS) { + if (min_valid) { + if (ptp->timeset[i].window < min_set) + min_set = ptp->timeset[i].window; + } else { + min_valid = true; + min_set = ptp->timeset[i].window; + } + } + } + + if (min_valid) { + if (ptp->base_sync_valid && (min_set > ptp->base_sync_ns)) + min = ptp->base_sync_ns; + else + min = min_set; + } else { + min = SYNCHRONISATION_GRANULARITY_NS; + } + + /* Discard excessively long synchronise durations. The MC times + * when it finishes reading the host time so the corrected window + * time should be fairly constant for a given platform. + */ + total = 0; + for (i = 0; i < number_readings; i++) + if (ptp->timeset[i].window > ptp->timeset[i].waitns) { + unsigned win; + + win = ptp->timeset[i].window - ptp->timeset[i].waitns; + if (win >= MIN_SYNCHRONISATION_NS && + win < MAX_SYNCHRONISATION_NS) { + total += ptp->timeset[i].window; + ngood++; + last_good = i; + } + } + + if (ngood == 0) { + netif_warn(efx, drv, efx->net_dev, + "PTP no suitable synchronisations %dns %dns\n", + ptp->base_sync_ns, min_set); + return -EAGAIN; + } + + /* Average minimum this synchronisation */ + ptp->last_sync_ns = DIV_ROUND_UP(total, ngood); + if (!ptp->base_sync_valid || (ptp->last_sync_ns < ptp->base_sync_ns)) { + ptp->base_sync_valid = true; + ptp->base_sync_ns = ptp->last_sync_ns; + } + + /* Calculate delay from actual PPS to last_time */ + delta.tv_nsec = + ptp->timeset[last_good].nanoseconds + + last_time->ts_real.tv_nsec - + (ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK); + + /* It is possible that the seconds rolled over between taking + * the start reading and the last value written by the host. The + * timescales are such that a gap of more than one second is never + * expected. + */ + start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS; + last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK; + if (start_sec != last_sec) { + if (((start_sec + 1) & MC_SECOND_MASK) != last_sec) { + netif_warn(efx, hw, efx->net_dev, + "PTP bad synchronisation seconds\n"); + return -EAGAIN; + } else { + delta.tv_sec = 1; + } + } else { + delta.tv_sec = 0; + } + + ptp->host_time_pps = *last_time; + pps_sub_ts(&ptp->host_time_pps, delta); + + return 0; +} + +/* Synchronize times between the host and the MC */ +static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + u8 synch_buf[MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX]; + size_t response_length; + int rc; + unsigned long timeout; + struct pps_event_time last_time = {}; + unsigned int loops = 0; + int *start = ptp->start.addr; + + MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE); + MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS, + num_readings); + MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR_LO, + (u32)ptp->start.dma_addr); + MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR_HI, + (u32)((u64)ptp->start.dma_addr >> 32)); + + /* Clear flag that signals MC ready */ + ACCESS_ONCE(*start) = 0; + efx_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf, + MC_CMD_PTP_IN_SYNCHRONIZE_LEN); + + /* Wait for start from MCDI (or timeout) */ + timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS); + while (!ACCESS_ONCE(*start) && (time_before(jiffies, timeout))) { + udelay(20); /* Usually start MCDI execution quickly */ + loops++; + } + + if (ACCESS_ONCE(*start)) + efx_ptp_send_times(efx, &last_time); + + /* Collect results */ + rc = efx_mcdi_rpc_finish(efx, MC_CMD_PTP, + MC_CMD_PTP_IN_SYNCHRONIZE_LEN, + synch_buf, sizeof(synch_buf), + &response_length); + if (rc == 0) + rc = efx_ptp_process_times(efx, synch_buf, response_length, + &last_time); + + return rc; +} + +/* Transmit a PTP packet, via the MCDI interface, to the wire. */ +static int efx_ptp_xmit_skb(struct efx_nic *efx, struct sk_buff *skb) +{ + u8 *txbuf = efx->ptp_data->txbuf; + struct skb_shared_hwtstamps timestamps; + int rc = -EIO; + /* MCDI driver requires word aligned lengths */ + size_t len = ALIGN(MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len), 4); + u8 txtime[MC_CMD_PTP_OUT_TRANSMIT_LEN]; + + MCDI_SET_DWORD(txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT); + MCDI_SET_DWORD(txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len); + if (skb_shinfo(skb)->nr_frags != 0) { + rc = skb_linearize(skb); + if (rc != 0) + goto fail; + } + + if (skb->ip_summed == CHECKSUM_PARTIAL) { + rc = skb_checksum_help(skb); + if (rc != 0) + goto fail; + } + skb_copy_from_linear_data(skb, + &txbuf[MC_CMD_PTP_IN_TRANSMIT_PACKET_OFST], + len); + rc = efx_mcdi_rpc(efx, MC_CMD_PTP, txbuf, len, txtime, + sizeof(txtime), &len); + if (rc != 0) + goto fail; + + memset(×tamps, 0, sizeof(timestamps)); + timestamps.hwtstamp = ktime_set( + MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_SECONDS), + MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_NANOSECONDS)); + + skb_tstamp_tx(skb, ×tamps); + + rc = 0; + +fail: + dev_kfree_skb(skb); + + return rc; +} + +static void efx_ptp_drop_time_expired_events(struct efx_nic *efx) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + struct list_head *cursor; + struct list_head *next; + + /* Drop time-expired events */ + spin_lock_bh(&ptp->evt_lock); + if (!list_empty(&ptp->evt_list)) { + list_for_each_safe(cursor, next, &ptp->evt_list) { + struct efx_ptp_event_rx *evt; + + evt = list_entry(cursor, struct efx_ptp_event_rx, + link); + if (time_after(jiffies, evt->expiry)) { + list_del(&evt->link); + list_add(&evt->link, &ptp->evt_free_list); + netif_warn(efx, hw, efx->net_dev, + "PTP rx event dropped\n"); + } + } + } + spin_unlock_bh(&ptp->evt_lock); +} + +static enum ptp_packet_state efx_ptp_match_rx(struct efx_nic *efx, + struct sk_buff *skb) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + bool evts_waiting; + struct list_head *cursor; + struct list_head *next; + struct efx_ptp_match *match; + enum ptp_packet_state rc = PTP_PACKET_STATE_UNMATCHED; + + spin_lock_bh(&ptp->evt_lock); + evts_waiting = !list_empty(&ptp->evt_list); + spin_unlock_bh(&ptp->evt_lock); + + if (!evts_waiting) + return PTP_PACKET_STATE_UNMATCHED; + + match = (struct efx_ptp_match *)skb->cb; + /* Look for a matching timestamp in the event queue */ + spin_lock_bh(&ptp->evt_lock); + list_for_each_safe(cursor, next, &ptp->evt_list) { + struct efx_ptp_event_rx *evt; + + evt = list_entry(cursor, struct efx_ptp_event_rx, link); + if ((evt->seq0 == match->words[0]) && + (evt->seq1 == match->words[1])) { + struct skb_shared_hwtstamps *timestamps; + + /* Match - add in hardware timestamp */ + timestamps = skb_hwtstamps(skb); + timestamps->hwtstamp = evt->hwtimestamp; + + match->state = PTP_PACKET_STATE_MATCHED; + rc = PTP_PACKET_STATE_MATCHED; + list_del(&evt->link); + list_add(&evt->link, &ptp->evt_free_list); + break; + } + } + spin_unlock_bh(&ptp->evt_lock); + + return rc; +} + +/* Process any queued receive events and corresponding packets + * + * q is returned with all the packets that are ready for delivery. + * true is returned if at least one of those packets requires + * synchronisation. + */ +static bool efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + bool rc = false; + struct sk_buff *skb; + + while ((skb = skb_dequeue(&ptp->rxq))) { + struct efx_ptp_match *match; + + match = (struct efx_ptp_match *)skb->cb; + if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) { + __skb_queue_tail(q, skb); + } else if (efx_ptp_match_rx(efx, skb) == + PTP_PACKET_STATE_MATCHED) { + rc = true; + __skb_queue_tail(q, skb); + } else if (time_after(jiffies, match->expiry)) { + match->state = PTP_PACKET_STATE_TIMED_OUT; + netif_warn(efx, rx_err, efx->net_dev, + "PTP packet - no timestamp seen\n"); + __skb_queue_tail(q, skb); + } else { + /* Replace unprocessed entry and stop */ + skb_queue_head(&ptp->rxq, skb); + break; + } + } + + return rc; +} + +/* Complete processing of a received packet */ +static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb) +{ + local_bh_disable(); + netif_receive_skb(skb); + local_bh_enable(); +} + +static int efx_ptp_start(struct efx_nic *efx) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + struct efx_filter_spec rxfilter; + int rc; + + ptp->reset_required = false; + + /* Must filter on both event and general ports to ensure + * that there is no packet re-ordering. + */ + efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0, + efx_rx_queue_index( + efx_channel_get_rx_queue(ptp->channel))); + rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP, + htonl(PTP_ADDRESS), + htons(PTP_EVENT_PORT)); + if (rc != 0) + return rc; + + rc = efx_filter_insert_filter(efx, &rxfilter, true); + if (rc < 0) + return rc; + ptp->rxfilter_event = rc; + + efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0, + efx_rx_queue_index( + efx_channel_get_rx_queue(ptp->channel))); + rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP, + htonl(PTP_ADDRESS), + htons(PTP_GENERAL_PORT)); + if (rc != 0) + goto fail; + + rc = efx_filter_insert_filter(efx, &rxfilter, true); + if (rc < 0) + goto fail; + ptp->rxfilter_general = rc; + + rc = efx_ptp_enable(efx); + if (rc != 0) + goto fail2; + + ptp->evt_frag_idx = 0; + ptp->current_adjfreq = 0; + ptp->rxfilter_installed = true; + + return 0; + +fail2: + efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, + ptp->rxfilter_general); +fail: + efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, + ptp->rxfilter_event); + + return rc; +} + +static int efx_ptp_stop(struct efx_nic *efx) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + int rc = efx_ptp_disable(efx); + struct list_head *cursor; + struct list_head *next; + + if (ptp->rxfilter_installed) { + efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, + ptp->rxfilter_general); + efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, + ptp->rxfilter_event); + ptp->rxfilter_installed = false; + } + + /* Make sure RX packets are really delivered */ + efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq); + skb_queue_purge(&efx->ptp_data->txq); + + /* Drop any pending receive events */ + spin_lock_bh(&efx->ptp_data->evt_lock); + list_for_each_safe(cursor, next, &efx->ptp_data->evt_list) { + list_del(cursor); + list_add(cursor, &efx->ptp_data->evt_free_list); + } + spin_unlock_bh(&efx->ptp_data->evt_lock); + + return rc; +} + +static void efx_ptp_pps_worker(struct work_struct *work) +{ + struct efx_ptp_data *ptp = + container_of(work, struct efx_ptp_data, pps_work); + struct efx_nic *efx = ptp->channel->efx; + struct ptp_clock_event ptp_evt; + + if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS)) + return; + + ptp_evt.type = PTP_CLOCK_PPSUSR; + ptp_evt.pps_times = ptp->host_time_pps; + ptp_clock_event(ptp->phc_clock, &ptp_evt); +} + +/* Process any pending transmissions and timestamp any received packets. + */ +static void efx_ptp_worker(struct work_struct *work) +{ + struct efx_ptp_data *ptp_data = + container_of(work, struct efx_ptp_data, work); + struct efx_nic *efx = ptp_data->channel->efx; + struct sk_buff *skb; + struct sk_buff_head tempq; + + if (ptp_data->reset_required) { + efx_ptp_stop(efx); + efx_ptp_start(efx); + return; + } + + efx_ptp_drop_time_expired_events(efx); + + __skb_queue_head_init(&tempq); + if (efx_ptp_process_events(efx, &tempq) || + !skb_queue_empty(&ptp_data->txq)) { + + while ((skb = skb_dequeue(&ptp_data->txq))) + efx_ptp_xmit_skb(efx, skb); + } + + while ((skb = __skb_dequeue(&tempq))) + efx_ptp_process_rx(efx, skb); +} + +/* Initialise PTP channel and state. + * + * Setting core_index to zero causes the queue to be initialised and doesn't + * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue. + */ +static int efx_ptp_probe_channel(struct efx_channel *channel) +{ + struct efx_nic *efx = channel->efx; + struct efx_ptp_data *ptp; + int rc = 0; + unsigned int pos; + + channel->irq_moderation = 0; + channel->rx_queue.core_index = 0; + + ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL); + efx->ptp_data = ptp; + if (!efx->ptp_data) + return -ENOMEM; + + rc = efx_nic_alloc_buffer(efx, &ptp->start, sizeof(int)); + if (rc != 0) + goto fail1; + + ptp->channel = channel; + skb_queue_head_init(&ptp->rxq); + skb_queue_head_init(&ptp->txq); + ptp->workwq = create_singlethread_workqueue("sfc_ptp"); + if (!ptp->workwq) { + rc = -ENOMEM; + goto fail2; + } + + INIT_WORK(&ptp->work, efx_ptp_worker); + ptp->config.flags = 0; + ptp->config.tx_type = HWTSTAMP_TX_OFF; + ptp->config.rx_filter = HWTSTAMP_FILTER_NONE; + INIT_LIST_HEAD(&ptp->evt_list); + INIT_LIST_HEAD(&ptp->evt_free_list); + spin_lock_init(&ptp->evt_lock); + for (pos = 0; pos < MAX_RECEIVE_EVENTS; pos++) + list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list); + + ptp->phc_clock_info.owner = THIS_MODULE; + snprintf(ptp->phc_clock_info.name, + sizeof(ptp->phc_clock_info.name), + "%pm", efx->net_dev->perm_addr); + ptp->phc_clock_info.max_adj = MAX_PPB; + ptp->phc_clock_info.n_alarm = 0; + ptp->phc_clock_info.n_ext_ts = 0; + ptp->phc_clock_info.n_per_out = 0; + ptp->phc_clock_info.pps = 1; + ptp->phc_clock_info.adjfreq = efx_phc_adjfreq; + ptp->phc_clock_info.adjtime = efx_phc_adjtime; + ptp->phc_clock_info.gettime = efx_phc_gettime; + ptp->phc_clock_info.settime = efx_phc_settime; + ptp->phc_clock_info.enable = efx_phc_enable; + + ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info); + if (!ptp->phc_clock) + goto fail3; + + INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker); + ptp->pps_workwq = create_singlethread_workqueue("sfc_pps"); + if (!ptp->pps_workwq) { + rc = -ENOMEM; + goto fail4; + } + ptp->nic_ts_enabled = false; + + return 0; +fail4: + ptp_clock_unregister(efx->ptp_data->phc_clock); + +fail3: + destroy_workqueue(efx->ptp_data->workwq); + +fail2: + efx_nic_free_buffer(efx, &ptp->start); + +fail1: + kfree(efx->ptp_data); + efx->ptp_data = NULL; + + return rc; +} + +static void efx_ptp_remove_channel(struct efx_channel *channel) +{ + struct efx_nic *efx = channel->efx; + + if (!efx->ptp_data) + return; + + (void)efx_ptp_disable(channel->efx); + + cancel_work_sync(&efx->ptp_data->work); + cancel_work_sync(&efx->ptp_data->pps_work); + + skb_queue_purge(&efx->ptp_data->rxq); + skb_queue_purge(&efx->ptp_data->txq); + + ptp_clock_unregister(efx->ptp_data->phc_clock); + + destroy_workqueue(efx->ptp_data->workwq); + destroy_workqueue(efx->ptp_data->pps_workwq); + + efx_nic_free_buffer(efx, &efx->ptp_data->start); + kfree(efx->ptp_data); +} + +static void efx_ptp_get_channel_name(struct efx_channel *channel, + char *buf, size_t len) +{ + snprintf(buf, len, "%s-ptp", channel->efx->name); +} + +/* Determine whether this packet should be processed by the PTP module + * or transmitted conventionally. + */ +bool efx_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb) +{ + return efx->ptp_data && + efx->ptp_data->enabled && + skb->len >= PTP_MIN_LENGTH && + skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM && + likely(skb->protocol == htons(ETH_P_IP)) && + ip_hdr(skb)->protocol == IPPROTO_UDP && + udp_hdr(skb)->dest == htons(PTP_EVENT_PORT); +} + +/* Receive a PTP packet. Packets are queued until the arrival of + * the receive timestamp from the MC - this will probably occur after the + * packet arrival because of the processing in the MC. + */ +static void efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb) +{ + struct efx_nic *efx = channel->efx; + struct efx_ptp_data *ptp = efx->ptp_data; + struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb; + u8 *data; + unsigned int version; + + match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS); + + /* Correct version? */ + if (ptp->mode == MC_CMD_PTP_MODE_V1) { + if (skb->len < PTP_V1_MIN_LENGTH) { + netif_receive_skb(skb); + return; + } + version = ntohs(*(__be16 *)&skb->data[PTP_V1_VERSION_OFFSET]); + if (version != PTP_VERSION_V1) { + netif_receive_skb(skb); + return; + } + } else { + if (skb->len < PTP_V2_MIN_LENGTH) { + netif_receive_skb(skb); + return; + } + version = skb->data[PTP_V2_VERSION_OFFSET]; + + BUG_ON(ptp->mode != MC_CMD_PTP_MODE_V2); + BUILD_BUG_ON(PTP_V1_UUID_OFFSET != PTP_V2_MC_UUID_OFFSET); + BUILD_BUG_ON(PTP_V1_UUID_LENGTH != PTP_V2_MC_UUID_LENGTH); + BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET); + BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH); + + if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) { + netif_receive_skb(skb); + return; + } + } + + /* Does this packet require timestamping? */ + if (ntohs(*(__be16 *)&skb->data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) { + struct skb_shared_hwtstamps *timestamps; + + match->state = PTP_PACKET_STATE_UNMATCHED; + + /* Clear all timestamps held: filled in later */ + timestamps = skb_hwtstamps(skb); + memset(timestamps, 0, sizeof(*timestamps)); + + /* Extract UUID/Sequence information */ + data = skb->data + PTP_V1_UUID_OFFSET; + match->words[0] = (data[0] | + (data[1] << 8) | + (data[2] << 16) | + (data[3] << 24)); + match->words[1] = (data[4] | + (data[5] << 8) | + (skb->data[PTP_V1_SEQUENCE_OFFSET + + PTP_V1_SEQUENCE_LENGTH - 1] << + 16)); + } else { + match->state = PTP_PACKET_STATE_MATCH_UNWANTED; + } + + skb_queue_tail(&ptp->rxq, skb); + queue_work(ptp->workwq, &ptp->work); +} + +/* Transmit a PTP packet. This has to be transmitted by the MC + * itself, through an MCDI call. MCDI calls aren't permitted + * in the transmit path so defer the actual transmission to a suitable worker. + */ +int efx_ptp_tx(struct efx_nic *efx, struct sk_buff *skb) +{ + struct efx_ptp_data *ptp = efx->ptp_data; + + skb_queue_tail(&ptp->txq, skb); + + if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) && + (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM)) + efx_xmit_hwtstamp_pending(skb); + queue_work(ptp->workwq, &ptp->work); + + return NETDEV_TX_OK; +} + +static int efx_ptp_change_mode(struct efx_nic *efx, bool enable_wanted, + unsigned int new_mode) +{ + if ((enable_wanted != efx->ptp_data->enabled) || + (enable_wanted && (efx->ptp_data-& |