1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // mcp251xfd - Microchip MCP251xFD Family CAN controller driver
4 //
5 // Copyright (c) 2021 Pengutronix,
6 // Marc Kleine-Budde <kernel@pengutronix.de>
7 //
8
9 #include <linux/clocksource.h>
10 #include <linux/workqueue.h>
11
12 #include "mcp251xfd.h"
13
mcp251xfd_timestamp_read(const struct cyclecounter * cc)14 static u64 mcp251xfd_timestamp_read(const struct cyclecounter *cc)
15 {
16 const struct mcp251xfd_priv *priv;
17 u32 timestamp = 0;
18 int err;
19
20 priv = container_of(cc, struct mcp251xfd_priv, cc);
21 err = mcp251xfd_get_timestamp(priv, ×tamp);
22 if (err)
23 netdev_err(priv->ndev,
24 "Error %d while reading timestamp. HW timestamps may be inaccurate.",
25 err);
26
27 return timestamp;
28 }
29
mcp251xfd_timestamp_work(struct work_struct * work)30 static void mcp251xfd_timestamp_work(struct work_struct *work)
31 {
32 struct delayed_work *delayed_work = to_delayed_work(work);
33 struct mcp251xfd_priv *priv;
34
35 priv = container_of(delayed_work, struct mcp251xfd_priv, timestamp);
36 timecounter_read(&priv->tc);
37
38 schedule_delayed_work(&priv->timestamp,
39 MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
40 }
41
mcp251xfd_skb_set_timestamp(const struct mcp251xfd_priv * priv,struct sk_buff * skb,u32 timestamp)42 void mcp251xfd_skb_set_timestamp(const struct mcp251xfd_priv *priv,
43 struct sk_buff *skb, u32 timestamp)
44 {
45 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
46 u64 ns;
47
48 ns = timecounter_cyc2time(&priv->tc, timestamp);
49 hwtstamps->hwtstamp = ns_to_ktime(ns);
50 }
51
mcp251xfd_timestamp_init(struct mcp251xfd_priv * priv)52 void mcp251xfd_timestamp_init(struct mcp251xfd_priv *priv)
53 {
54 struct cyclecounter *cc = &priv->cc;
55
56 cc->read = mcp251xfd_timestamp_read;
57 cc->mask = CYCLECOUNTER_MASK(32);
58 cc->shift = 1;
59 cc->mult = clocksource_hz2mult(priv->can.clock.freq, cc->shift);
60
61 timecounter_init(&priv->tc, &priv->cc, ktime_get_real_ns());
62
63 INIT_DELAYED_WORK(&priv->timestamp, mcp251xfd_timestamp_work);
64 schedule_delayed_work(&priv->timestamp,
65 MCP251XFD_TIMESTAMP_WORK_DELAY_SEC * HZ);
66 }
67
mcp251xfd_timestamp_stop(struct mcp251xfd_priv * priv)68 void mcp251xfd_timestamp_stop(struct mcp251xfd_priv *priv)
69 {
70 cancel_delayed_work_sync(&priv->timestamp);
71 }
72