--- /dev/null
+/*
+ * 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"
+
+#ifdef CONFIG_TI_CPTS
+
+#define cpts_read32(c, r) __raw_readl(&c->reg->r)
+#define cpts_write32(c, v, r) __raw_writel(v, &c->reg->r)
+
+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;
+}
+
+/*
+ * 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)) {
+ pr_err("cpts: event pool is 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_PUSH:
+ case CPTS_EV_RX:
+ case CPTS_EV_TX:
+ 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 cycle_t 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 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,
+};
+
+static void cpts_overflow_check(struct work_struct *work)
+{
+ struct timespec64 ts;
+ struct cpts *cpts = container_of(work, struct cpts, overflow_work.work);
+
+ cpts_write32(cpts, CPTS_EN, control);
+ cpts_write32(cpts, TS_PEND_EN, int_enable);
+ cpts_ptp_gettime(&cpts->info, &ts);
+ pr_debug("cpts overflow check at %lld.%09lu\n", ts.tv_sec, ts.tv_nsec);
+ schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
+}
+
+static void cpts_clk_init(struct device *dev, struct cpts *cpts)
+{
+ cpts->refclk = devm_clk_get(dev, "cpts");
+ if (IS_ERR(cpts->refclk)) {
+ dev_err(dev, "Failed to get cpts refclk\n");
+ cpts->refclk = NULL;
+ return;
+ }
+ clk_prepare_enable(cpts->refclk);
+}
+
+static void cpts_clk_release(struct cpts *cpts)
+{
+ clk_disable(cpts->refclk);
+}
+
+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, CPTS_EV_PUSH);
+ 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;
+ }
+ }
+ 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);
+}
+
+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);
+}
+
+#endif /*CONFIG_TI_CPTS*/
+
+int cpts_register(struct device *dev, struct cpts *cpts,
+ u32 mult, u32 shift)
+{
+#ifdef CONFIG_TI_CPTS
+ int err, i;
+ unsigned long flags;
+
+ cpts->info = cpts_info;
+ cpts->clock = ptp_clock_register(&cpts->info, dev);
+ if (IS_ERR(cpts->clock)) {
+ err = PTR_ERR(cpts->clock);
+ cpts->clock = NULL;
+ return err;
+ }
+ spin_lock_init(&cpts->lock);
+
+ cpts->cc.read = cpts_systim_read;
+ cpts->cc.mask = CLOCKSOURCE_MASK(32);
+ cpts->cc_mult = mult;
+ cpts->cc.mult = mult;
+ cpts->cc.shift = shift;
+
+ 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);
+
+ cpts_clk_init(dev, cpts);
+ cpts_write32(cpts, CPTS_EN, control);
+ cpts_write32(cpts, TS_PEND_EN, int_enable);
+
+ spin_lock_irqsave(&cpts->lock, flags);
+ timecounter_init(&cpts->tc, &cpts->cc, ktime_to_ns(ktime_get_real()));
+ spin_unlock_irqrestore(&cpts->lock, flags);
+
+ INIT_DELAYED_WORK(&cpts->overflow_work, cpts_overflow_check);
+ schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
+
+ cpts->phc_index = ptp_clock_index(cpts->clock);
+#endif
+ return 0;
+}
+
+void cpts_unregister(struct cpts *cpts)
+{
+#ifdef CONFIG_TI_CPTS
+ if (cpts->clock) {
+ ptp_clock_unregister(cpts->clock);
+ cancel_delayed_work_sync(&cpts->overflow_work);
+ }
+ if (cpts->refclk)
+ cpts_clk_release(cpts);
+#endif
+}
Code Review / kvmfornfv.git / blobdiff