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  **/
37 static 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  **/
88 static 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  **/
109 static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
110 {
111 	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
112 						     ptp_clock_info);
113 	unsigned long flags;
114 	u32 remainder;
115 	u64 ns;
116 
117 	spin_lock_irqsave(&adapter->systim_lock, flags);
118 	ns = timecounter_read(&adapter->tc);
119 	spin_unlock_irqrestore(&adapter->systim_lock, flags);
120 
121 	ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
122 	ts->tv_nsec = remainder;
123 
124 	return 0;
125 }
126 
127 /**
128  * e1000e_phc_settime - Set the current time on the hardware clock
129  * @ptp: ptp clock structure
130  * @ts: timespec containing the new time for the cycle counter
131  *
132  * Reset the timecounter to use a new base value instead of the kernel
133  * wall timer value.
134  **/
135 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
136 			      const struct timespec *ts)
137 {
138 	struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
139 						     ptp_clock_info);
140 	unsigned long flags;
141 	u64 ns;
142 
143 	ns = timespec_to_ns(ts);
144 
145 	/* reset the timecounter */
146 	spin_lock_irqsave(&adapter->systim_lock, flags);
147 	timecounter_init(&adapter->tc, &adapter->cc, ns);
148 	spin_unlock_irqrestore(&adapter->systim_lock, flags);
149 
150 	return 0;
151 }
152 
153 /**
154  * e1000e_phc_enable - enable or disable an ancillary feature
155  * @ptp: ptp clock structure
156  * @request: Desired resource to enable or disable
157  * @on: Caller passes one to enable or zero to disable
158  *
159  * Enable (or disable) ancillary features of the PHC subsystem.
160  * Currently, no ancillary features are supported.
161  **/
162 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
163 			     struct ptp_clock_request __always_unused *request,
164 			     int __always_unused on)
165 {
166 	return -EOPNOTSUPP;
167 }
168 
169 static void e1000e_systim_overflow_work(struct work_struct *work)
170 {
171 	struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
172 						     systim_overflow_work.work);
173 	struct e1000_hw *hw = &adapter->hw;
174 	struct timespec ts;
175 
176 	adapter->ptp_clock_info.gettime(&adapter->ptp_clock_info, &ts);
177 
178 	e_dbg("SYSTIM overflow check at %ld.%09lu\n", ts.tv_sec, ts.tv_nsec);
179 
180 	schedule_delayed_work(&adapter->systim_overflow_work,
181 			      E1000_SYSTIM_OVERFLOW_PERIOD);
182 }
183 
184 static const struct ptp_clock_info e1000e_ptp_clock_info = {
185 	.owner		= THIS_MODULE,
186 	.n_alarm	= 0,
187 	.n_ext_ts	= 0,
188 	.n_per_out	= 0,
189 	.n_pins		= 0,
190 	.pps		= 0,
191 	.adjfreq	= e1000e_phc_adjfreq,
192 	.adjtime	= e1000e_phc_adjtime,
193 	.gettime	= e1000e_phc_gettime,
194 	.settime	= e1000e_phc_settime,
195 	.enable		= e1000e_phc_enable,
196 };
197 
198 /**
199  * e1000e_ptp_init - initialize PTP for devices which support it
200  * @adapter: board private structure
201  *
202  * This function performs the required steps for enabling PTP support.
203  * If PTP support has already been loaded it simply calls the cyclecounter
204  * init routine and exits.
205  **/
206 void e1000e_ptp_init(struct e1000_adapter *adapter)
207 {
208 	struct e1000_hw *hw = &adapter->hw;
209 
210 	adapter->ptp_clock = NULL;
211 
212 	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
213 		return;
214 
215 	adapter->ptp_clock_info = e1000e_ptp_clock_info;
216 
217 	snprintf(adapter->ptp_clock_info.name,
218 		 sizeof(adapter->ptp_clock_info.name), "%pm",
219 		 adapter->netdev->perm_addr);
220 
221 	switch (hw->mac.type) {
222 	case e1000_pch2lan:
223 	case e1000_pch_lpt:
224 		if ((hw->mac.type != e1000_pch_lpt) ||
225 		    (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
226 			adapter->ptp_clock_info.max_adj = 24000000 - 1;
227 			break;
228 		}
229 		/* fall-through */
230 	case e1000_82574:
231 	case e1000_82583:
232 		adapter->ptp_clock_info.max_adj = 600000000 - 1;
233 		break;
234 	default:
235 		break;
236 	}
237 
238 	INIT_DELAYED_WORK(&adapter->systim_overflow_work,
239 			  e1000e_systim_overflow_work);
240 
241 	schedule_delayed_work(&adapter->systim_overflow_work,
242 			      E1000_SYSTIM_OVERFLOW_PERIOD);
243 
244 	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
245 						&adapter->pdev->dev);
246 	if (IS_ERR(adapter->ptp_clock)) {
247 		adapter->ptp_clock = NULL;
248 		e_err("ptp_clock_register failed\n");
249 	} else {
250 		e_info("registered PHC clock\n");
251 	}
252 }
253 
254 /**
255  * e1000e_ptp_remove - disable PTP device and stop the overflow check
256  * @adapter: board private structure
257  *
258  * Stop the PTP support, and cancel the delayed work.
259  **/
260 void e1000e_ptp_remove(struct e1000_adapter *adapter)
261 {
262 	if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
263 		return;
264 
265 	cancel_delayed_work_sync(&adapter->systim_overflow_work);
266 
267 	if (adapter->ptp_clock) {
268 		ptp_clock_unregister(adapter->ptp_clock);
269 		adapter->ptp_clock = NULL;
270 		e_info("removed PHC\n");
271 	}
272 }
273