summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c
blob: 1477471f8d4455ab27151c617a0c92a488648562 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*******************************************************************************
  PTP 1588 clock using the STMMAC.

  Copyright (C) 2013  Vayavya Labs Pvt Ltd

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope 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.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Author: Rayagond Kokatanur <rayagond@vayavyalabs.com>
*******************************************************************************/
#include "stmmac.h"
#include "stmmac_ptp.h"

/**
 * stmmac_adjust_freq
 *
 * @ptp: pointer to ptp_clock_info structure
 * @ppb: desired period change in parts ber billion
 *
 * Description: this function will adjust the frequency of hardware clock.
 */
static int stmmac_adjust_freq(struct ptp_clock_info *ptp, s32 ppb)
{
	struct stmmac_priv *priv =
	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u32 diff, addend;
	int neg_adj = 0;
	u64 adj;

	if (ppb < 0) {
		neg_adj = 1;
		ppb = -ppb;
	}

	addend = priv->default_addend;
	adj = addend;
	adj *= ppb;
	diff = div_u64(adj, 1000000000ULL);
	addend = neg_adj ? (addend - diff) : (addend + diff);

	spin_lock_irqsave(&priv->ptp_lock, flags);

	priv->hw->ptp->config_addend(priv->ioaddr, addend);

	spin_unlock_irqrestore(&priv->ptp_lock, flags);

	return 0;
}

/**
 * stmmac_adjust_time
 *
 * @ptp: pointer to ptp_clock_info structure
 * @delta: desired change in nanoseconds
 *
 * Description: this function will shift/adjust the hardware clock time.
 */
static int stmmac_adjust_time(struct ptp_clock_info *ptp, s64 delta)
{
	struct stmmac_priv *priv =
	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u32 sec, nsec;
	u32 quotient, reminder;
	int neg_adj = 0;

	if (delta < 0) {
		neg_adj = 1;
		delta = -delta;
	}

	quotient = div_u64_rem(delta, 1000000000ULL, &reminder);
	sec = quotient;
	nsec = reminder;

	spin_lock_irqsave(&priv->ptp_lock, flags);

	priv->hw->ptp->adjust_systime(priv->ioaddr, sec, nsec, neg_adj);

	spin_unlock_irqrestore(&priv->ptp_lock, flags);

	return 0;
}

/**
 * stmmac_get_time
 *
 * @ptp: pointer to ptp_clock_info structure
 * @ts: pointer to hold time/result
 *
 * Description: this function will read the current time from the
 * hardware clock and store it in @ts.
 */
static int stmmac_get_time(struct ptp_clock_info *ptp, struct timespec64 *ts)
{
	struct stmmac_priv *priv =
	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;
	u64 ns;

	spin_lock_irqsave(&priv->ptp_lock, flags);

	ns = priv->hw->ptp->get_systime(priv->ioaddr);

	spin_unlock_irqrestore(&priv->ptp_lock, flags);

	*ts = ns_to_timespec64(ns);

	return 0;
}

/**
 * stmmac_set_time
 *
 * @ptp: pointer to ptp_clock_info structure
 * @ts: time value to set
 *
 * Description: this function will set the current time on the
 * hardware clock.
 */
static int stmmac_set_time(struct ptp_clock_info *ptp,
			   const struct timespec64 *ts)
{
	struct stmmac_priv *priv =
	    container_of(ptp, struct stmmac_priv, ptp_clock_ops);
	unsigned long flags;

	spin_lock_irqsave(&priv->ptp_lock, flags);

	priv->hw->ptp->init_systime(priv->ioaddr, ts->tv_sec, ts->tv_nsec);

	spin_unlock_irqrestore(&priv->ptp_lock, flags);

	return 0;
}

static int stmmac_enable(struct ptp_clock_info *ptp,
			 struct ptp_clock_request *rq, int on)
{
	return -EOPNOTSUPP;
}

/* structure describing a PTP hardware clock */
static struct ptp_clock_info stmmac_ptp_clock_ops = {
	.owner = THIS_MODULE,
	.name = "stmmac_ptp_clock",
	.max_adj = 62500000,
	.n_alarm = 0,
	.n_ext_ts = 0,
	.n_per_out = 0,
	.n_pins = 0,
	.pps = 0,
	.adjfreq = stmmac_adjust_freq,
	.adjtime = stmmac_adjust_time,
	.gettime64 = stmmac_get_time,
	.settime64 = stmmac_set_time,
	.enable = stmmac_enable,
};

/**
 * stmmac_ptp_register
 * @priv: driver private structure
 * Description: this function will register the ptp clock driver
 * to kernel. It also does some house keeping work.
 */
void stmmac_ptp_register(struct stmmac_priv *priv)
{
	spin_lock_init(&priv->ptp_lock);
	priv->ptp_clock_ops = stmmac_ptp_clock_ops;

	priv->ptp_clock = ptp_clock_register(&priv->ptp_clock_ops,
					     priv->device);
	if (IS_ERR(priv->ptp_clock)) {
		netdev_err(priv->dev, "ptp_clock_register failed\n");
		priv->ptp_clock = NULL;
	} else if (priv->ptp_clock)
		netdev_info(priv->dev, "registered PTP clock\n");
}

/**
 * stmmac_ptp_unregister
 * @priv: driver private structure
 * Description: this function will remove/unregister the ptp clock driver
 * from the kernel.
 */
void stmmac_ptp_unregister(struct stmmac_priv *priv)
{
	if (priv->ptp_clock) {
		ptp_clock_unregister(priv->ptp_clock);
		priv->ptp_clock = NULL;
		pr_debug("Removed PTP HW clock successfully on %s\n",
			 priv->dev->name);
	}
}