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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/net/ethernet/ti/cpts.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/ethernet/ti/cpts.c')
-rw-r--r-- | drivers/net/ethernet/ti/cpts.c | 609 |
1 files changed, 609 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c new file mode 100644 index 000000000..01cc92f6a --- /dev/null +++ b/drivers/net/ethernet/ti/cpts.c @@ -0,0 +1,609 @@ +/* + * TI Common Platform Time Sync + * + * Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#include <linux/err.h> +#include <linux/if.h> +#include <linux/hrtimer.h> +#include <linux/module.h> +#include <linux/net_tstamp.h> +#include <linux/ptp_classify.h> +#include <linux/time.h> +#include <linux/uaccess.h> +#include <linux/workqueue.h> +#include <linux/if_ether.h> +#include <linux/if_vlan.h> + +#include "cpts.h" + +#define CPTS_SKB_TX_WORK_TIMEOUT 1 /* jiffies */ + +struct cpts_skb_cb_data { + unsigned long tmo; +}; + +#define cpts_read32(c, r) readl_relaxed(&c->reg->r) +#define cpts_write32(c, v, r) writel_relaxed(v, &c->reg->r) + +static int cpts_match(struct sk_buff *skb, unsigned int ptp_class, + u16 ts_seqid, u8 ts_msgtype); + +static int event_expired(struct cpts_event *event) +{ + return time_after(jiffies, event->tmo); +} + +static int event_type(struct cpts_event *event) +{ + return (event->high >> EVENT_TYPE_SHIFT) & EVENT_TYPE_MASK; +} + +static int cpts_fifo_pop(struct cpts *cpts, u32 *high, u32 *low) +{ + u32 r = cpts_read32(cpts, intstat_raw); + + if (r & TS_PEND_RAW) { + *high = cpts_read32(cpts, event_high); + *low = cpts_read32(cpts, event_low); + cpts_write32(cpts, EVENT_POP, event_pop); + return 0; + } + 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; +} + +static bool cpts_match_tx_ts(struct cpts *cpts, struct cpts_event *event) +{ + struct sk_buff *skb, *tmp; + u16 seqid; + u8 mtype; + bool found = false; + + mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK; + seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK; + + /* no need to grab txq.lock as access is always done under cpts->lock */ + skb_queue_walk_safe(&cpts->txq, skb, tmp) { + struct skb_shared_hwtstamps ssh; + unsigned int class = ptp_classify_raw(skb); + struct cpts_skb_cb_data *skb_cb = + (struct cpts_skb_cb_data *)skb->cb; + + if (cpts_match(skb, class, seqid, mtype)) { + u64 ns = timecounter_cyc2time(&cpts->tc, event->low); + + memset(&ssh, 0, sizeof(ssh)); + ssh.hwtstamp = ns_to_ktime(ns); + skb_tstamp_tx(skb, &ssh); + found = true; + __skb_unlink(skb, &cpts->txq); + dev_consume_skb_any(skb); + dev_dbg(cpts->dev, "match tx timestamp mtype %u seqid %04x\n", + mtype, seqid); + break; + } + + if (time_after(jiffies, skb_cb->tmo)) { + /* timeout any expired skbs over 1s */ + dev_dbg(cpts->dev, "expiring tx timestamp from txq\n"); + __skb_unlink(skb, &cpts->txq); + dev_consume_skb_any(skb); + } + } + + return found; +} + +/* + * Returns zero if matching event type was found. + */ +static int cpts_fifo_read(struct cpts *cpts, int match) +{ + int i, type = -1; + u32 hi, lo; + struct cpts_event *event; + + for (i = 0; i < CPTS_FIFO_DEPTH; i++) { + if (cpts_fifo_pop(cpts, &hi, &lo)) + break; + + 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; + event->low = lo; + type = event_type(event); + switch (type) { + case CPTS_EV_TX: + if (cpts_match_tx_ts(cpts, event)) { + /* if the new event matches an existing skb, + * then don't queue it + */ + break; + } + /* fall through */ + case CPTS_EV_PUSH: + case CPTS_EV_RX: + list_del_init(&event->list); + list_add_tail(&event->list, &cpts->events); + break; + case CPTS_EV_ROLL: + case CPTS_EV_HALF: + case CPTS_EV_HW: + break; + default: + pr_err("cpts: unknown event type\n"); + break; + } + if (type == match) + break; + } + return type == match ? 0 : -1; +} + +static u64 cpts_systim_read(const struct cyclecounter *cc) +{ + u64 val = 0; + struct cpts_event *event; + struct list_head *this, *next; + struct cpts *cpts = container_of(cc, struct cpts, cc); + + cpts_write32(cpts, TS_PUSH, ts_push); + if (cpts_fifo_read(cpts, CPTS_EV_PUSH)) + pr_err("cpts: unable to obtain a time stamp\n"); + + list_for_each_safe(this, next, &cpts->events) { + event = list_entry(this, struct cpts_event, list); + if (event_type(event) == CPTS_EV_PUSH) { + list_del_init(&event->list); + list_add(&event->list, &cpts->pool); + val = event->low; + break; + } + } + + return val; +} + +/* PTP clock operations */ + +static int cpts_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) +{ + u64 adj; + u32 diff, mult; + int neg_adj = 0; + unsigned long flags; + struct cpts *cpts = container_of(ptp, struct cpts, info); + + if (ppb < 0) { + neg_adj = 1; + ppb = -ppb; + } + mult = cpts->cc_mult; + adj = mult; + adj *= ppb; + diff = div_u64(adj, 1000000000ULL); + + spin_lock_irqsave(&cpts->lock, flags); + + timecounter_read(&cpts->tc); + + cpts->cc.mult = neg_adj ? mult - diff : mult + diff; + + spin_unlock_irqrestore(&cpts->lock, flags); + + return 0; +} + +static int cpts_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + unsigned long flags; + struct cpts *cpts = container_of(ptp, struct cpts, info); + + spin_lock_irqsave(&cpts->lock, flags); + timecounter_adjtime(&cpts->tc, delta); + spin_unlock_irqrestore(&cpts->lock, flags); + + return 0; +} + +static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) +{ + u64 ns; + unsigned long flags; + struct cpts *cpts = container_of(ptp, struct cpts, info); + + spin_lock_irqsave(&cpts->lock, flags); + ns = timecounter_read(&cpts->tc); + spin_unlock_irqrestore(&cpts->lock, flags); + + *ts = ns_to_timespec64(ns); + + return 0; +} + +static int cpts_ptp_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + u64 ns; + unsigned long flags; + struct cpts *cpts = container_of(ptp, struct cpts, info); + + ns = timespec64_to_ns(ts); + + spin_lock_irqsave(&cpts->lock, flags); + timecounter_init(&cpts->tc, &cpts->cc, ns); + spin_unlock_irqrestore(&cpts->lock, flags); + + return 0; +} + +static int cpts_ptp_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + return -EOPNOTSUPP; +} + +static long cpts_overflow_check(struct ptp_clock_info *ptp) +{ + struct cpts *cpts = container_of(ptp, struct cpts, info); + unsigned long delay = cpts->ov_check_period; + struct timespec64 ts; + unsigned long flags; + + spin_lock_irqsave(&cpts->lock, flags); + ts = ns_to_timespec64(timecounter_read(&cpts->tc)); + + if (!skb_queue_empty(&cpts->txq)) + delay = CPTS_SKB_TX_WORK_TIMEOUT; + spin_unlock_irqrestore(&cpts->lock, flags); + + pr_debug("cpts overflow check at %lld.%09ld\n", + (long long)ts.tv_sec, ts.tv_nsec); + return (long)delay; +} + +static const struct ptp_clock_info cpts_info = { + .owner = THIS_MODULE, + .name = "CTPS timer", + .max_adj = 1000000, + .n_ext_ts = 0, + .n_pins = 0, + .pps = 0, + .adjfreq = cpts_ptp_adjfreq, + .adjtime = cpts_ptp_adjtime, + .gettime64 = cpts_ptp_gettime, + .settime64 = cpts_ptp_settime, + .enable = cpts_ptp_enable, + .do_aux_work = cpts_overflow_check, +}; + +static int cpts_match(struct sk_buff *skb, unsigned int ptp_class, + u16 ts_seqid, u8 ts_msgtype) +{ + u16 *seqid; + unsigned int offset = 0; + u8 *msgtype, *data = skb->data; + + if (ptp_class & PTP_CLASS_VLAN) + offset += VLAN_HLEN; + + switch (ptp_class & PTP_CLASS_PMASK) { + case PTP_CLASS_IPV4: + offset += ETH_HLEN + IPV4_HLEN(data + offset) + UDP_HLEN; + break; + case PTP_CLASS_IPV6: + offset += ETH_HLEN + IP6_HLEN + UDP_HLEN; + break; + case PTP_CLASS_L2: + offset += ETH_HLEN; + break; + default: + return 0; + } + + if (skb->len + ETH_HLEN < offset + OFF_PTP_SEQUENCE_ID + sizeof(*seqid)) + return 0; + + if (unlikely(ptp_class & PTP_CLASS_V1)) + msgtype = data + offset + OFF_PTP_CONTROL; + else + msgtype = data + offset; + + seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID); + + return (ts_msgtype == (*msgtype & 0xf) && ts_seqid == ntohs(*seqid)); +} + +static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type) +{ + u64 ns = 0; + struct cpts_event *event; + struct list_head *this, *next; + unsigned int class = ptp_classify_raw(skb); + unsigned long flags; + u16 seqid; + u8 mtype; + + if (class == PTP_CLASS_NONE) + return 0; + + spin_lock_irqsave(&cpts->lock, flags); + cpts_fifo_read(cpts, -1); + 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); + continue; + } + mtype = (event->high >> MESSAGE_TYPE_SHIFT) & MESSAGE_TYPE_MASK; + seqid = (event->high >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MASK; + if (ev_type == event_type(event) && + cpts_match(skb, class, seqid, mtype)) { + ns = timecounter_cyc2time(&cpts->tc, event->low); + list_del_init(&event->list); + list_add(&event->list, &cpts->pool); + break; + } + } + + if (ev_type == CPTS_EV_TX && !ns) { + struct cpts_skb_cb_data *skb_cb = + (struct cpts_skb_cb_data *)skb->cb; + /* Not found, add frame to queue for processing later. + * The periodic FIFO check will handle this. + */ + skb_get(skb); + /* get the timestamp for timeouts */ + skb_cb->tmo = jiffies + msecs_to_jiffies(100); + __skb_queue_tail(&cpts->txq, skb); + ptp_schedule_worker(cpts->clock, 0); + } + spin_unlock_irqrestore(&cpts->lock, flags); + + return ns; +} + +void cpts_rx_timestamp(struct cpts *cpts, struct sk_buff *skb) +{ + u64 ns; + struct skb_shared_hwtstamps *ssh; + + if (!cpts->rx_enable) + return; + ns = cpts_find_ts(cpts, skb, CPTS_EV_RX); + if (!ns) + return; + ssh = skb_hwtstamps(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) +{ + u64 ns; + struct skb_shared_hwtstamps ssh; + + if (!(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) + return; + ns = cpts_find_ts(cpts, skb, CPTS_EV_TX); + if (!ns) + return; + memset(&ssh, 0, sizeof(ssh)); + ssh.hwtstamp = ns_to_ktime(ns); + skb_tstamp_tx(skb, &ssh); +} +EXPORT_SYMBOL_GPL(cpts_tx_timestamp); + +int cpts_register(struct cpts *cpts) +{ + int err, i; + + skb_queue_head_init(&cpts->txq); + 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); + + err = clk_enable(cpts->refclk); + if (err) + return err; + + cpts_write32(cpts, CPTS_EN, control); + cpts_write32(cpts, TS_PEND_EN, int_enable); + + timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real())); + + 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); + + ptp_schedule_worker(cpts->clock, 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) +{ + if (WARN_ON(!cpts->clock)) + return; + + ptp_clock_unregister(cpts->clock); + cpts->clock = NULL; + cpts->phc_index = -1; + + cpts_write32(cpts, 0, int_enable); + cpts_write32(cpts, 0, control); + + /* Drop all packet */ + skb_queue_purge(&cpts->txq); + + 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); + + 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_CAST(cpts->refclk); + } + + ret = clk_prepare(cpts->refclk); + if (ret) + return ERR_PTR(ret); + + cpts->cc.read = cpts_systim_read; + cpts->cc.mask = CLOCKSOURCE_MASK(32); + cpts->info = cpts_info; + cpts->phc_index = -1; + + 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>"); |