ptp.c 7.65 KB
Newer Older
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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
/*******************************************************************************

  Intel PRO/1000 Linux driver
  Copyright(c) 1999 - 2012 Intel Corporation.

  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".

  Contact Information:
  Linux NICS <linux.nics@intel.com>
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

*******************************************************************************/

/* PTP 1588 Hardware Clock (PHC)
 * Derived from PTP Hardware Clock driver for Intel 82576 and 82580 (igb)
 * Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com>
 */

#include "e1000.h"

/**
 * e1000e_phc_adjfreq - adjust the frequency of the hardware clock
 * @ptp: ptp clock structure
 * @delta: Desired frequency change in parts per billion
 *
 * Adjust the frequency of the PHC cycle counter by the indicated delta from
 * the base frequency.
 **/
static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
{
	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
						     ptp_clock_info);
	struct e1000_hw *hw = &adapter->hw;
	bool neg_adj = false;
	u64 adjustment;
	u32 timinca, incvalue;
	s32 ret_val;

	if ((delta > ptp->max_adj) || (delta <= -1000000000))
		return -EINVAL;

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

	/* Get the System Time Register SYSTIM base frequency */
	ret_val = e1000e_get_base_timinca(adapter, &timinca);
	if (ret_val)
		return ret_val;

	incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;

	adjustment = incvalue;
	adjustment *= delta;
	adjustment = div_u64(adjustment, 1000000000);

	incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment);

	timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
	timinca |= incvalue;

	ew32(TIMINCA, timinca);

	return 0;
}

/**
 * e1000e_phc_adjtime - Shift the time of the hardware clock
 * @ptp: ptp clock structure
 * @delta: Desired change in nanoseconds
 *
 * Adjust the timer by resetting the timecounter structure.
 **/
static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
						     ptp_clock_info);
	unsigned long flags;
	s64 now;

	spin_lock_irqsave(&adapter->systim_lock, flags);
	now = timecounter_read(&adapter->tc);
	now += delta;
	timecounter_init(&adapter->tc, &adapter->cc, now);
	spin_unlock_irqrestore(&adapter->systim_lock, flags);

	return 0;
}

/**
 * e1000e_phc_gettime - Reads the current time from the hardware clock
 * @ptp: ptp clock structure
 * @ts: timespec structure to hold the current time value
 *
 * Read the timecounter and return the correct value in ns after converting
 * it into a struct timespec.
 **/
static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
{
	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
						     ptp_clock_info);
	unsigned long flags;
	u32 remainder;
	u64 ns;

	spin_lock_irqsave(&adapter->systim_lock, flags);
	ns = timecounter_read(&adapter->tc);
	spin_unlock_irqrestore(&adapter->systim_lock, flags);

	ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
	ts->tv_nsec = remainder;

	return 0;
}

/**
 * e1000e_phc_settime - Set the current time on the hardware clock
 * @ptp: ptp clock structure
 * @ts: timespec containing the new time for the cycle counter
 *
 * Reset the timecounter to use a new base value instead of the kernel
 * wall timer value.
 **/
static int e1000e_phc_settime(struct ptp_clock_info *ptp,
			      const struct timespec *ts)
{
	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
						     ptp_clock_info);
	unsigned long flags;
	u64 ns;

	ns = ts->tv_sec * NSEC_PER_SEC;
	ns += ts->tv_nsec;

	/* reset the timecounter */
	spin_lock_irqsave(&adapter->systim_lock, flags);
	timecounter_init(&adapter->tc, &adapter->cc, ns);
	spin_unlock_irqrestore(&adapter->systim_lock, flags);

	return 0;
}

/**
 * e1000e_phc_enable - enable or disable an ancillary feature
 * @ptp: ptp clock structure
 * @request: Desired resource to enable or disable
 * @on: Caller passes one to enable or zero to disable
 *
 * Enable (or disable) ancillary features of the PHC subsystem.
 * Currently, no ancillary features are supported.
 **/
static int e1000e_phc_enable(struct ptp_clock_info *ptp,
			     struct ptp_clock_request *request, int on)
{
	return -EOPNOTSUPP;
}

static void e1000e_systim_overflow_work(struct work_struct *work)
{
	struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
						     systim_overflow_work.work);
	struct e1000_hw *hw = &adapter->hw;
	struct timespec ts;

	adapter->ptp_clock_info.gettime(&adapter->ptp_clock_info, &ts);

	e_dbg("SYSTIM overflow check at %ld.%09lu\n", ts.tv_sec, ts.tv_nsec);

	schedule_delayed_work(&adapter->systim_overflow_work,
			      E1000_SYSTIM_OVERFLOW_PERIOD);
}

static const struct ptp_clock_info e1000e_ptp_clock_info = {
	.owner		= THIS_MODULE,
	.n_alarm	= 0,
	.n_ext_ts	= 0,
	.n_per_out	= 0,
	.pps		= 0,
	.adjfreq	= e1000e_phc_adjfreq,
	.adjtime	= e1000e_phc_adjtime,
	.gettime	= e1000e_phc_gettime,
	.settime	= e1000e_phc_settime,
	.enable		= e1000e_phc_enable,
};

/**
 * e1000e_ptp_init - initialize PTP for devices which support it
 * @adapter: board private structure
 *
 * This function performs the required steps for enabling PTP support.
 * If PTP support has already been loaded it simply calls the cyclecounter
 * init routine and exits.
 **/
void e1000e_ptp_init(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;

	adapter->ptp_clock = NULL;

	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
		return;

	adapter->ptp_clock_info = e1000e_ptp_clock_info;

	snprintf(adapter->ptp_clock_info.name,
		 sizeof(adapter->ptp_clock_info.name), "%pm",
		 adapter->netdev->perm_addr);

	switch (hw->mac.type) {
	case e1000_pch2lan:
	case e1000_pch_lpt:
		if ((hw->mac.type != e1000_pch_lpt) ||
		    (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
			adapter->ptp_clock_info.max_adj = 24000000 - 1;
			break;
		}
		/* fall-through */
	case e1000_82574:
	case e1000_82583:
		adapter->ptp_clock_info.max_adj = 600000000 - 1;
		break;
	default:
		break;
	}

	INIT_DELAYED_WORK(&adapter->systim_overflow_work,
			  e1000e_systim_overflow_work);

	schedule_delayed_work(&adapter->systim_overflow_work,
			      E1000_SYSTIM_OVERFLOW_PERIOD);

	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
						&adapter->pdev->dev);
	if (IS_ERR(adapter->ptp_clock)) {
		adapter->ptp_clock = NULL;
		e_err("ptp_clock_register failed\n");
	} else {
		e_info("registered PHC clock\n");
	}
}

/**
 * e1000e_ptp_remove - disable PTP device and stop the overflow check
 * @adapter: board private structure
 *
 * Stop the PTP support, and cancel the delayed work.
 **/
void e1000e_ptp_remove(struct e1000_adapter *adapter)
{
	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
		return;

	cancel_delayed_work_sync(&adapter->systim_overflow_work);

	if (adapter->ptp_clock) {
		ptp_clock_unregister(adapter->ptp_clock);
		adapter->ptp_clock = NULL;
		e_info("removed PHC\n");
	}
}