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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/net/ethernet/ti/cpts.c
parentInitial commit. (diff)
downloadlinux-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.c609
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>");