1/* Intel PRO/1000 Linux driver
2 * Copyright(c) 1999 - 2014 Intel Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11 * more details.
12 *
13 * The full GNU General Public License is included in this distribution in
14 * the file called "COPYING".
15 *
16 * Contact Information:
17 * Linux NICS <linux.nics@intel.com>
18 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
19 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
20 */
21
22/* PTP 1588 Hardware Clock (PHC)
23 * Derived from PTP Hardware Clock driver for Intel 82576 and 82580 (igb)
24 * Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com>
25 */
26
27#include "e1000.h"
28
29/**
30 * e1000e_phc_adjfreq - adjust the frequency of the hardware clock
31 * @ptp: ptp clock structure
32 * @delta: Desired frequency change in parts per billion
33 *
34 * Adjust the frequency of the PHC cycle counter by the indicated delta from
35 * the base frequency.
36 **/
37static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
38{
39	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
40						     ptp_clock_info);
41	struct e1000_hw *hw = &adapter->hw;
42	bool neg_adj = false;
43	unsigned long flags;
44	u64 adjustment;
45	u32 timinca, incvalue;
46	s32 ret_val;
47
48	if ((delta > ptp->max_adj) || (delta <= -1000000000))
49		return -EINVAL;
50
51	if (delta < 0) {
52		neg_adj = true;
53		delta = -delta;
54	}
55
56	/* Get the System Time Register SYSTIM base frequency */
57	ret_val = e1000e_get_base_timinca(adapter, &timinca);
58	if (ret_val)
59		return ret_val;
60
61	spin_lock_irqsave(&adapter->systim_lock, flags);
62
63	incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;
64
65	adjustment = incvalue;
66	adjustment *= delta;
67	adjustment = div_u64(adjustment, 1000000000);
68
69	incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment);
70
71	timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
72	timinca |= incvalue;
73
74	ew32(TIMINCA, timinca);
75
76	spin_unlock_irqrestore(&adapter->systim_lock, flags);
77
78	return 0;
79}
80
81/**
82 * e1000e_phc_adjtime - Shift the time of the hardware clock
83 * @ptp: ptp clock structure
84 * @delta: Desired change in nanoseconds
85 *
86 * Adjust the timer by resetting the timecounter structure.
87 **/
88static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
89{
90	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
91						     ptp_clock_info);
92	unsigned long flags;
93
94	spin_lock_irqsave(&adapter->systim_lock, flags);
95	timecounter_adjtime(&adapter->tc, delta);
96	spin_unlock_irqrestore(&adapter->systim_lock, flags);
97
98	return 0;
99}
100
101/**
102 * e1000e_phc_gettime - Reads the current time from the hardware clock
103 * @ptp: ptp clock structure
104 * @ts: timespec structure to hold the current time value
105 *
106 * Read the timecounter and return the correct value in ns after converting
107 * it into a struct timespec.
108 **/
109static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
110{
111	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
112						     ptp_clock_info);
113	unsigned long flags;
114	u64 ns;
115
116	spin_lock_irqsave(&adapter->systim_lock, flags);
117	ns = timecounter_read(&adapter->tc);
118	spin_unlock_irqrestore(&adapter->systim_lock, flags);
119
120	*ts = ns_to_timespec64(ns);
121
122	return 0;
123}
124
125/**
126 * e1000e_phc_settime - Set the current time on the hardware clock
127 * @ptp: ptp clock structure
128 * @ts: timespec containing the new time for the cycle counter
129 *
130 * Reset the timecounter to use a new base value instead of the kernel
131 * wall timer value.
132 **/
133static int e1000e_phc_settime(struct ptp_clock_info *ptp,
134			      const struct timespec64 *ts)
135{
136	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
137						     ptp_clock_info);
138	unsigned long flags;
139	u64 ns;
140
141	ns = timespec64_to_ns(ts);
142
143	/* reset the timecounter */
144	spin_lock_irqsave(&adapter->systim_lock, flags);
145	timecounter_init(&adapter->tc, &adapter->cc, ns);
146	spin_unlock_irqrestore(&adapter->systim_lock, flags);
147
148	return 0;
149}
150
151/**
152 * e1000e_phc_enable - enable or disable an ancillary feature
153 * @ptp: ptp clock structure
154 * @request: Desired resource to enable or disable
155 * @on: Caller passes one to enable or zero to disable
156 *
157 * Enable (or disable) ancillary features of the PHC subsystem.
158 * Currently, no ancillary features are supported.
159 **/
160static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
161			     struct ptp_clock_request __always_unused *request,
162			     int __always_unused on)
163{
164	return -EOPNOTSUPP;
165}
166
167static void e1000e_systim_overflow_work(struct work_struct *work)
168{
169	struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
170						     systim_overflow_work.work);
171	struct e1000_hw *hw = &adapter->hw;
172	struct timespec64 ts;
173
174	adapter->ptp_clock_info.gettime64(&adapter->ptp_clock_info, &ts);
175
176	e_dbg("SYSTIM overflow check at %lld.%09lu\n",
177	      (long long) ts.tv_sec, ts.tv_nsec);
178
179	schedule_delayed_work(&adapter->systim_overflow_work,
180			      E1000_SYSTIM_OVERFLOW_PERIOD);
181}
182
183static const struct ptp_clock_info e1000e_ptp_clock_info = {
184	.owner		= THIS_MODULE,
185	.n_alarm	= 0,
186	.n_ext_ts	= 0,
187	.n_per_out	= 0,
188	.n_pins		= 0,
189	.pps		= 0,
190	.adjfreq	= e1000e_phc_adjfreq,
191	.adjtime	= e1000e_phc_adjtime,
192	.gettime64	= e1000e_phc_gettime,
193	.settime64	= e1000e_phc_settime,
194	.enable		= e1000e_phc_enable,
195};
196
197/**
198 * e1000e_ptp_init - initialize PTP for devices which support it
199 * @adapter: board private structure
200 *
201 * This function performs the required steps for enabling PTP support.
202 * If PTP support has already been loaded it simply calls the cyclecounter
203 * init routine and exits.
204 **/
205void e1000e_ptp_init(struct e1000_adapter *adapter)
206{
207	struct e1000_hw *hw = &adapter->hw;
208
209	adapter->ptp_clock = NULL;
210
211	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
212		return;
213
214	adapter->ptp_clock_info = e1000e_ptp_clock_info;
215
216	snprintf(adapter->ptp_clock_info.name,
217		 sizeof(adapter->ptp_clock_info.name), "%pm",
218		 adapter->netdev->perm_addr);
219
220	switch (hw->mac.type) {
221	case e1000_pch2lan:
222	case e1000_pch_lpt:
223	case e1000_pch_spt:
224		if (((hw->mac.type != e1000_pch_lpt) &&
225		     (hw->mac.type != e1000_pch_spt)) ||
226		    (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
227			adapter->ptp_clock_info.max_adj = 24000000 - 1;
228			break;
229		}
230		/* fall-through */
231	case e1000_82574:
232	case e1000_82583:
233		adapter->ptp_clock_info.max_adj = 600000000 - 1;
234		break;
235	default:
236		break;
237	}
238
239	INIT_DELAYED_WORK(&adapter->systim_overflow_work,
240			  e1000e_systim_overflow_work);
241
242	schedule_delayed_work(&adapter->systim_overflow_work,
243			      E1000_SYSTIM_OVERFLOW_PERIOD);
244
245	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
246						&adapter->pdev->dev);
247	if (IS_ERR(adapter->ptp_clock)) {
248		adapter->ptp_clock = NULL;
249		e_err("ptp_clock_register failed\n");
250	} else {
251		e_info("registered PHC clock\n");
252	}
253}
254
255/**
256 * e1000e_ptp_remove - disable PTP device and stop the overflow check
257 * @adapter: board private structure
258 *
259 * Stop the PTP support, and cancel the delayed work.
260 **/
261void e1000e_ptp_remove(struct e1000_adapter *adapter)
262{
263	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
264		return;
265
266	cancel_delayed_work_sync(&adapter->systim_overflow_work);
267
268	if (adapter->ptp_clock) {
269		ptp_clock_unregister(adapter->ptp_clock);
270		adapter->ptp_clock = NULL;
271		e_info("removed PHC\n");
272	}
273}
274