1 files changed, 424 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
new file mode 100644
index 000000000000..463597f919f1
--- /dev/null
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -0,0 +1,424 @@
+/*
+ * 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 "cpts.h"
+
+#ifdef CONFIG_TI_CPTS
+
+static struct sock_filter ptp_filter[] = {
+	PTP_FILTER
+};
+
+#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: unkown 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)
+{
+	s64 now;
+	unsigned long flags;
+	struct cpts *cpts = container_of(ptp, struct cpts, info);
+
+	spin_lock_irqsave(&cpts->lock, flags);
+	now = timecounter_read(&cpts->tc);
+	now += delta;
+	timecounter_init(&cpts->tc, &cpts->cc, now);
+	spin_unlock_irqrestore(&cpts->lock, flags);
+
+	return 0;
+}
+
+static int cpts_ptp_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
+{
+	u64 ns;
+	u32 remainder;
+	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->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
+	ts->tv_nsec = remainder;
+
+	return 0;
+}
+
+static int cpts_ptp_settime(struct ptp_clock_info *ptp,
+			    const struct timespec *ts)
+{
+	u64 ns;
+	unsigned long flags;
+	struct cpts *cpts = container_of(ptp, struct cpts, info);
+
+	ns = ts->tv_sec * 1000000000ULL;
+	ns += ts->tv_nsec;
+
+	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,
+	.pps		= 0,
+	.adjfreq	= cpts_ptp_adjfreq,
+	.adjtime	= cpts_ptp_adjtime,
+	.gettime	= cpts_ptp_gettime,
+	.settime	= cpts_ptp_settime,
+	.enable		= cpts_ptp_enable,
+};
+
+static void cpts_overflow_check(struct work_struct *work)
+{
+	struct timespec 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 %ld.%09lu\n", ts.tv_sec, ts.tv_nsec);
+	schedule_delayed_work(&cpts->overflow_work, CPTS_OVERFLOW_PERIOD);
+}
+
+#define CPTS_REF_CLOCK_NAME "cpsw_cpts_rft_clk"
+
+static void cpts_clk_init(struct cpts *cpts)
+{
+	cpts->refclk = clk_get(NULL, CPTS_REF_CLOCK_NAME);
+	if (IS_ERR(cpts->refclk)) {
+		pr_err("Failed to clk_get %s\n", CPTS_REF_CLOCK_NAME);
+		cpts->refclk = NULL;
+		return;
+	}
+	clk_prepare_enable(cpts->refclk);
+}
+
+static void cpts_clk_release(struct cpts *cpts)
+{
+	clk_disable(cpts->refclk);
+	clk_put(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;
+	u8 *msgtype, *data = skb->data;
+
+	switch (ptp_class) {
+	case PTP_CLASS_V1_IPV4:
+	case PTP_CLASS_V2_IPV4:
+		offset = ETH_HLEN + IPV4_HLEN(data) + UDP_HLEN;
+		break;
+	case PTP_CLASS_V1_IPV6:
+	case PTP_CLASS_V2_IPV6:
+		offset = OFF_PTP6;
+		break;
+	case PTP_CLASS_V2_L2:
+		offset = ETH_HLEN;
+		break;
+	case PTP_CLASS_V2_VLAN:
+		offset = ETH_HLEN + VLAN_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 = sk_run_filter(skb, ptp_filter);
+	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;
+
+	if (ptp_filter_init(ptp_filter, ARRAY_SIZE(ptp_filter))) {
+		pr_err("cpts: bad ptp filter\n");
+		return -EINVAL;
+	}
+	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(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
+}