1 /*
2  * Copyright (c) 2012 Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 
34 #include <linux/mlx4/device.h>
35 
36 #include "mlx4_en.h"
37 
38 int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
39 {
40 	struct mlx4_en_priv *priv = netdev_priv(dev);
41 	struct mlx4_en_dev *mdev = priv->mdev;
42 	int port_up = 0;
43 	int err = 0;
44 
45 	if (priv->hwtstamp_config.tx_type == tx_type &&
46 	    priv->hwtstamp_config.rx_filter == rx_filter)
47 		return 0;
48 
49 	mutex_lock(&mdev->state_lock);
50 	if (priv->port_up) {
51 		port_up = 1;
52 		mlx4_en_stop_port(dev, 1);
53 	}
54 
55 	mlx4_en_free_resources(priv);
56 
57 	en_warn(priv, "Changing Time Stamp configuration\n");
58 
59 	priv->hwtstamp_config.tx_type = tx_type;
60 	priv->hwtstamp_config.rx_filter = rx_filter;
61 
62 	if (rx_filter != HWTSTAMP_FILTER_NONE)
63 		dev->features &= ~NETIF_F_HW_VLAN_CTAG_RX;
64 	else
65 		dev->features |= NETIF_F_HW_VLAN_CTAG_RX;
66 
67 	err = mlx4_en_alloc_resources(priv);
68 	if (err) {
69 		en_err(priv, "Failed reallocating port resources\n");
70 		goto out;
71 	}
72 	if (port_up) {
73 		err = mlx4_en_start_port(dev);
74 		if (err)
75 			en_err(priv, "Failed starting port\n");
76 	}
77 
78 out:
79 	mutex_unlock(&mdev->state_lock);
80 	netdev_features_change(dev);
81 	return err;
82 }
83 
84 /* mlx4_en_read_clock - read raw cycle counter (to be used by time counter)
85  */
86 static cycle_t mlx4_en_read_clock(const struct cyclecounter *tc)
87 {
88 	struct mlx4_en_dev *mdev =
89 		container_of(tc, struct mlx4_en_dev, cycles);
90 	struct mlx4_dev *dev = mdev->dev;
91 
92 	return mlx4_read_clock(dev) & tc->mask;
93 }
94 
95 u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
96 {
97 	u64 hi, lo;
98 	struct mlx4_ts_cqe *ts_cqe = (struct mlx4_ts_cqe *)cqe;
99 
100 	lo = (u64)be16_to_cpu(ts_cqe->timestamp_lo);
101 	hi = ((u64)be32_to_cpu(ts_cqe->timestamp_hi) + !lo) << 16;
102 
103 	return hi | lo;
104 }
105 
106 void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
107 			    struct skb_shared_hwtstamps *hwts,
108 			    u64 timestamp)
109 {
110 	unsigned long flags;
111 	u64 nsec;
112 
113 	read_lock_irqsave(&mdev->clock_lock, flags);
114 	nsec = timecounter_cyc2time(&mdev->clock, timestamp);
115 	read_unlock_irqrestore(&mdev->clock_lock, flags);
116 
117 	memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
118 	hwts->hwtstamp = ns_to_ktime(nsec);
119 }
120 
121 /**
122  * mlx4_en_remove_timestamp - disable PTP device
123  * @mdev: board private structure
124  *
125  * Stop the PTP support.
126  **/
127 void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev)
128 {
129 	if (mdev->ptp_clock) {
130 		ptp_clock_unregister(mdev->ptp_clock);
131 		mdev->ptp_clock = NULL;
132 		mlx4_info(mdev, "removed PHC\n");
133 	}
134 }
135 
136 void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
137 {
138 	bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
139 					      mdev->overflow_period);
140 	unsigned long flags;
141 
142 	if (timeout) {
143 		write_lock_irqsave(&mdev->clock_lock, flags);
144 		timecounter_read(&mdev->clock);
145 		write_unlock_irqrestore(&mdev->clock_lock, flags);
146 		mdev->last_overflow_check = jiffies;
147 	}
148 }
149 
150 /**
151  * mlx4_en_phc_adjfreq - adjust the frequency of the hardware clock
152  * @ptp: ptp clock structure
153  * @delta: Desired frequency change in parts per billion
154  *
155  * Adjust the frequency of the PHC cycle counter by the indicated delta from
156  * the base frequency.
157  **/
158 static int mlx4_en_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
159 {
160 	u64 adj;
161 	u32 diff, mult;
162 	int neg_adj = 0;
163 	unsigned long flags;
164 	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
165 						ptp_clock_info);
166 
167 	if (delta < 0) {
168 		neg_adj = 1;
169 		delta = -delta;
170 	}
171 	mult = mdev->nominal_c_mult;
172 	adj = mult;
173 	adj *= delta;
174 	diff = div_u64(adj, 1000000000ULL);
175 
176 	write_lock_irqsave(&mdev->clock_lock, flags);
177 	timecounter_read(&mdev->clock);
178 	mdev->cycles.mult = neg_adj ? mult - diff : mult + diff;
179 	write_unlock_irqrestore(&mdev->clock_lock, flags);
180 
181 	return 0;
182 }
183 
184 /**
185  * mlx4_en_phc_adjtime - Shift the time of the hardware clock
186  * @ptp: ptp clock structure
187  * @delta: Desired change in nanoseconds
188  *
189  * Adjust the timer by resetting the timecounter structure.
190  **/
191 static int mlx4_en_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
192 {
193 	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
194 						ptp_clock_info);
195 	unsigned long flags;
196 	s64 now;
197 
198 	write_lock_irqsave(&mdev->clock_lock, flags);
199 	now = timecounter_read(&mdev->clock);
200 	now += delta;
201 	timecounter_init(&mdev->clock, &mdev->cycles, now);
202 	write_unlock_irqrestore(&mdev->clock_lock, flags);
203 
204 	return 0;
205 }
206 
207 /**
208  * mlx4_en_phc_gettime - Reads the current time from the hardware clock
209  * @ptp: ptp clock structure
210  * @ts: timespec structure to hold the current time value
211  *
212  * Read the timecounter and return the correct value in ns after converting
213  * it into a struct timespec.
214  **/
215 static int mlx4_en_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
216 {
217 	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
218 						ptp_clock_info);
219 	unsigned long flags;
220 	u32 remainder;
221 	u64 ns;
222 
223 	write_lock_irqsave(&mdev->clock_lock, flags);
224 	ns = timecounter_read(&mdev->clock);
225 	write_unlock_irqrestore(&mdev->clock_lock, flags);
226 
227 	ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
228 	ts->tv_nsec = remainder;
229 
230 	return 0;
231 }
232 
233 /**
234  * mlx4_en_phc_settime - Set the current time on the hardware clock
235  * @ptp: ptp clock structure
236  * @ts: timespec containing the new time for the cycle counter
237  *
238  * Reset the timecounter to use a new base value instead of the kernel
239  * wall timer value.
240  **/
241 static int mlx4_en_phc_settime(struct ptp_clock_info *ptp,
242 			       const struct timespec *ts)
243 {
244 	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
245 						ptp_clock_info);
246 	u64 ns = timespec_to_ns(ts);
247 	unsigned long flags;
248 
249 	/* reset the timecounter */
250 	write_lock_irqsave(&mdev->clock_lock, flags);
251 	timecounter_init(&mdev->clock, &mdev->cycles, ns);
252 	write_unlock_irqrestore(&mdev->clock_lock, flags);
253 
254 	return 0;
255 }
256 
257 /**
258  * mlx4_en_phc_enable - enable or disable an ancillary feature
259  * @ptp: ptp clock structure
260  * @request: Desired resource to enable or disable
261  * @on: Caller passes one to enable or zero to disable
262  *
263  * Enable (or disable) ancillary features of the PHC subsystem.
264  * Currently, no ancillary features are supported.
265  **/
266 static int mlx4_en_phc_enable(struct ptp_clock_info __always_unused *ptp,
267 			      struct ptp_clock_request __always_unused *request,
268 			      int __always_unused on)
269 {
270 	return -EOPNOTSUPP;
271 }
272 
273 static const struct ptp_clock_info mlx4_en_ptp_clock_info = {
274 	.owner		= THIS_MODULE,
275 	.max_adj	= 100000000,
276 	.n_alarm	= 0,
277 	.n_ext_ts	= 0,
278 	.n_per_out	= 0,
279 	.pps		= 0,
280 	.adjfreq	= mlx4_en_phc_adjfreq,
281 	.adjtime	= mlx4_en_phc_adjtime,
282 	.gettime	= mlx4_en_phc_gettime,
283 	.settime	= mlx4_en_phc_settime,
284 	.enable		= mlx4_en_phc_enable,
285 };
286 
287 void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
288 {
289 	struct mlx4_dev *dev = mdev->dev;
290 	unsigned long flags;
291 	u64 ns;
292 
293 	rwlock_init(&mdev->clock_lock);
294 
295 	memset(&mdev->cycles, 0, sizeof(mdev->cycles));
296 	mdev->cycles.read = mlx4_en_read_clock;
297 	mdev->cycles.mask = CLOCKSOURCE_MASK(48);
298 	/* Using shift to make calculation more accurate. Since current HW
299 	 * clock frequency is 427 MHz, and cycles are given using a 48 bits
300 	 * register, the biggest shift when calculating using u64, is 14
301 	 * (max_cycles * multiplier < 2^64)
302 	 */
303 	mdev->cycles.shift = 14;
304 	mdev->cycles.mult =
305 		clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
306 	mdev->nominal_c_mult = mdev->cycles.mult;
307 
308 	write_lock_irqsave(&mdev->clock_lock, flags);
309 	timecounter_init(&mdev->clock, &mdev->cycles,
310 			 ktime_to_ns(ktime_get_real()));
311 	write_unlock_irqrestore(&mdev->clock_lock, flags);
312 
313 	/* Calculate period in seconds to call the overflow watchdog - to make
314 	 * sure counter is checked at least once every wrap around.
315 	 */
316 	ns = cyclecounter_cyc2ns(&mdev->cycles, mdev->cycles.mask);
317 	do_div(ns, NSEC_PER_SEC / 2 / HZ);
318 	mdev->overflow_period = ns;
319 
320 	/* Configure the PHC */
321 	mdev->ptp_clock_info = mlx4_en_ptp_clock_info;
322 	snprintf(mdev->ptp_clock_info.name, 16, "mlx4 ptp");
323 
324 	mdev->ptp_clock = ptp_clock_register(&mdev->ptp_clock_info,
325 					     &mdev->pdev->dev);
326 	if (IS_ERR(mdev->ptp_clock)) {
327 		mdev->ptp_clock = NULL;
328 		mlx4_err(mdev, "ptp_clock_register failed\n");
329 	} else {
330 		mlx4_info(mdev, "registered PHC clock\n");
331 	}
332 
333 }
334