1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 1999 - 2018 Intel Corporation. */
3
4 /* PTP 1588 Hardware Clock (PHC)
5 * Derived from PTP Hardware Clock driver for Intel 82576 and 82580 (igb)
6 * Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com>
7 */
8
9 #include "e1000.h"
10
11 #ifdef CONFIG_E1000E_HWTS
12 #include <linux/clocksource.h>
13 #include <linux/ktime.h>
14 #include <asm/tsc.h>
15 #endif
16
17 /**
18 * e1000e_phc_adjfreq - adjust the frequency of the hardware clock
19 * @ptp: ptp clock structure
20 * @delta: Desired frequency change in parts per billion
21 *
22 * Adjust the frequency of the PHC cycle counter by the indicated delta from
23 * the base frequency.
24 **/
e1000e_phc_adjfreq(struct ptp_clock_info * ptp,s32 delta)25 static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
26 {
27 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
28 ptp_clock_info);
29 struct e1000_hw *hw = &adapter->hw;
30 bool neg_adj = false;
31 unsigned long flags;
32 u64 adjustment;
33 u32 timinca, incvalue;
34 s32 ret_val;
35
36 if ((delta > ptp->max_adj) || (delta <= -1000000000))
37 return -EINVAL;
38
39 if (delta < 0) {
40 neg_adj = true;
41 delta = -delta;
42 }
43
44 /* Get the System Time Register SYSTIM base frequency */
45 ret_val = e1000e_get_base_timinca(adapter, &timinca);
46 if (ret_val)
47 return ret_val;
48
49 spin_lock_irqsave(&adapter->systim_lock, flags);
50
51 incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;
52
53 adjustment = incvalue;
54 adjustment *= delta;
55 adjustment = div_u64(adjustment, 1000000000);
56
57 incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment);
58
59 timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
60 timinca |= incvalue;
61
62 ew32(TIMINCA, timinca);
63
64 adapter->ptp_delta = delta;
65
66 spin_unlock_irqrestore(&adapter->systim_lock, flags);
67
68 return 0;
69 }
70
71 /**
72 * e1000e_phc_adjtime - Shift the time of the hardware clock
73 * @ptp: ptp clock structure
74 * @delta: Desired change in nanoseconds
75 *
76 * Adjust the timer by resetting the timecounter structure.
77 **/
e1000e_phc_adjtime(struct ptp_clock_info * ptp,s64 delta)78 static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
79 {
80 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
81 ptp_clock_info);
82 unsigned long flags;
83
84 spin_lock_irqsave(&adapter->systim_lock, flags);
85 timecounter_adjtime(&adapter->tc, delta);
86 spin_unlock_irqrestore(&adapter->systim_lock, flags);
87
88 return 0;
89 }
90
91 #ifdef CONFIG_E1000E_HWTS
92 #define MAX_HW_WAIT_COUNT (3)
93
94 /**
95 * e1000e_phc_get_syncdevicetime - Callback given to timekeeping code reads system/device registers
96 * @device: current device time
97 * @system: system counter value read synchronously with device time
98 * @ctx: context provided by timekeeping code
99 *
100 * Read device and system (ART) clock simultaneously and return the corrected
101 * clock values in ns.
102 **/
e1000e_phc_get_syncdevicetime(ktime_t * device,struct system_counterval_t * system,void * ctx)103 static int e1000e_phc_get_syncdevicetime(ktime_t *device,
104 struct system_counterval_t *system,
105 void *ctx)
106 {
107 struct e1000_adapter *adapter = (struct e1000_adapter *)ctx;
108 struct e1000_hw *hw = &adapter->hw;
109 unsigned long flags;
110 int i;
111 u32 tsync_ctrl;
112 u64 dev_cycles;
113 u64 sys_cycles;
114
115 tsync_ctrl = er32(TSYNCTXCTL);
116 tsync_ctrl |= E1000_TSYNCTXCTL_START_SYNC |
117 E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK;
118 ew32(TSYNCTXCTL, tsync_ctrl);
119 for (i = 0; i < MAX_HW_WAIT_COUNT; ++i) {
120 udelay(1);
121 tsync_ctrl = er32(TSYNCTXCTL);
122 if (tsync_ctrl & E1000_TSYNCTXCTL_SYNC_COMP)
123 break;
124 }
125
126 if (i == MAX_HW_WAIT_COUNT)
127 return -ETIMEDOUT;
128
129 dev_cycles = er32(SYSSTMPH);
130 dev_cycles <<= 32;
131 dev_cycles |= er32(SYSSTMPL);
132 spin_lock_irqsave(&adapter->systim_lock, flags);
133 *device = ns_to_ktime(timecounter_cyc2time(&adapter->tc, dev_cycles));
134 spin_unlock_irqrestore(&adapter->systim_lock, flags);
135
136 sys_cycles = er32(PLTSTMPH);
137 sys_cycles <<= 32;
138 sys_cycles |= er32(PLTSTMPL);
139 *system = convert_art_to_tsc(sys_cycles);
140
141 return 0;
142 }
143
144 /**
145 * e1000e_phc_getsynctime - Reads the current system/device cross timestamp
146 * @ptp: ptp clock structure
147 * @cts: structure containing timestamp
148 *
149 * Read device and system (ART) clock simultaneously and return the scaled
150 * clock values in ns.
151 **/
e1000e_phc_getcrosststamp(struct ptp_clock_info * ptp,struct system_device_crosststamp * xtstamp)152 static int e1000e_phc_getcrosststamp(struct ptp_clock_info *ptp,
153 struct system_device_crosststamp *xtstamp)
154 {
155 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
156 ptp_clock_info);
157
158 return get_device_system_crosststamp(e1000e_phc_get_syncdevicetime,
159 adapter, NULL, xtstamp);
160 }
161 #endif/*CONFIG_E1000E_HWTS*/
162
163 /**
164 * e1000e_phc_gettime - Reads the current time from the hardware clock
165 * @ptp: ptp clock structure
166 * @ts: timespec structure to hold the current time value
167 *
168 * Read the timecounter and return the correct value in ns after converting
169 * it into a struct timespec.
170 **/
e1000e_phc_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)171 static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
172 {
173 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
174 ptp_clock_info);
175 unsigned long flags;
176 u64 cycles, ns;
177
178 spin_lock_irqsave(&adapter->systim_lock, flags);
179
180 /* Use timecounter_cyc2time() to allow non-monotonic SYSTIM readings */
181 cycles = adapter->cc.read(&adapter->cc);
182 ns = timecounter_cyc2time(&adapter->tc, cycles);
183
184 spin_unlock_irqrestore(&adapter->systim_lock, flags);
185
186 *ts = ns_to_timespec64(ns);
187
188 return 0;
189 }
190
191 /**
192 * e1000e_phc_settime - Set the current time on the hardware clock
193 * @ptp: ptp clock structure
194 * @ts: timespec containing the new time for the cycle counter
195 *
196 * Reset the timecounter to use a new base value instead of the kernel
197 * wall timer value.
198 **/
e1000e_phc_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)199 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
200 const struct timespec64 *ts)
201 {
202 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
203 ptp_clock_info);
204 unsigned long flags;
205 u64 ns;
206
207 ns = timespec64_to_ns(ts);
208
209 /* reset the timecounter */
210 spin_lock_irqsave(&adapter->systim_lock, flags);
211 timecounter_init(&adapter->tc, &adapter->cc, ns);
212 spin_unlock_irqrestore(&adapter->systim_lock, flags);
213
214 return 0;
215 }
216
217 /**
218 * e1000e_phc_enable - enable or disable an ancillary feature
219 * @ptp: ptp clock structure
220 * @request: Desired resource to enable or disable
221 * @on: Caller passes one to enable or zero to disable
222 *
223 * Enable (or disable) ancillary features of the PHC subsystem.
224 * Currently, no ancillary features are supported.
225 **/
e1000e_phc_enable(struct ptp_clock_info __always_unused * ptp,struct ptp_clock_request __always_unused * request,int __always_unused on)226 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
227 struct ptp_clock_request __always_unused *request,
228 int __always_unused on)
229 {
230 return -EOPNOTSUPP;
231 }
232
e1000e_systim_overflow_work(struct work_struct * work)233 static void e1000e_systim_overflow_work(struct work_struct *work)
234 {
235 struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
236 systim_overflow_work.work);
237 struct e1000_hw *hw = &adapter->hw;
238 struct timespec64 ts;
239 u64 ns;
240
241 /* Update the timecounter */
242 ns = timecounter_read(&adapter->tc);
243
244 ts = ns_to_timespec64(ns);
245 e_dbg("SYSTIM overflow check at %lld.%09lu\n",
246 (long long) ts.tv_sec, ts.tv_nsec);
247
248 schedule_delayed_work(&adapter->systim_overflow_work,
249 E1000_SYSTIM_OVERFLOW_PERIOD);
250 }
251
252 static const struct ptp_clock_info e1000e_ptp_clock_info = {
253 .owner = THIS_MODULE,
254 .n_alarm = 0,
255 .n_ext_ts = 0,
256 .n_per_out = 0,
257 .n_pins = 0,
258 .pps = 0,
259 .adjfreq = e1000e_phc_adjfreq,
260 .adjtime = e1000e_phc_adjtime,
261 .gettime64 = e1000e_phc_gettime,
262 .settime64 = e1000e_phc_settime,
263 .enable = e1000e_phc_enable,
264 };
265
266 /**
267 * e1000e_ptp_init - initialize PTP for devices which support it
268 * @adapter: board private structure
269 *
270 * This function performs the required steps for enabling PTP support.
271 * If PTP support has already been loaded it simply calls the cyclecounter
272 * init routine and exits.
273 **/
e1000e_ptp_init(struct e1000_adapter * adapter)274 void e1000e_ptp_init(struct e1000_adapter *adapter)
275 {
276 struct e1000_hw *hw = &adapter->hw;
277
278 adapter->ptp_clock = NULL;
279
280 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
281 return;
282
283 adapter->ptp_clock_info = e1000e_ptp_clock_info;
284
285 snprintf(adapter->ptp_clock_info.name,
286 sizeof(adapter->ptp_clock_info.name), "%pm",
287 adapter->netdev->perm_addr);
288
289 switch (hw->mac.type) {
290 case e1000_pch2lan:
291 case e1000_pch_lpt:
292 case e1000_pch_spt:
293 case e1000_pch_cnp:
294 if ((hw->mac.type < e1000_pch_lpt) ||
295 (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
296 adapter->ptp_clock_info.max_adj = 24000000 - 1;
297 break;
298 }
299 /* fall-through */
300 case e1000_82574:
301 case e1000_82583:
302 adapter->ptp_clock_info.max_adj = 600000000 - 1;
303 break;
304 default:
305 break;
306 }
307
308 #ifdef CONFIG_E1000E_HWTS
309 /* CPU must have ART and GBe must be from Sunrise Point or greater */
310 if (hw->mac.type >= e1000_pch_spt && boot_cpu_has(X86_FEATURE_ART))
311 adapter->ptp_clock_info.getcrosststamp =
312 e1000e_phc_getcrosststamp;
313 #endif/*CONFIG_E1000E_HWTS*/
314
315 INIT_DELAYED_WORK(&adapter->systim_overflow_work,
316 e1000e_systim_overflow_work);
317
318 schedule_delayed_work(&adapter->systim_overflow_work,
319 E1000_SYSTIM_OVERFLOW_PERIOD);
320
321 adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
322 &adapter->pdev->dev);
323 if (IS_ERR(adapter->ptp_clock)) {
324 adapter->ptp_clock = NULL;
325 e_err("ptp_clock_register failed\n");
326 } else if (adapter->ptp_clock) {
327 e_info("registered PHC clock\n");
328 }
329 }
330
331 /**
332 * e1000e_ptp_remove - disable PTP device and stop the overflow check
333 * @adapter: board private structure
334 *
335 * Stop the PTP support, and cancel the delayed work.
336 **/
e1000e_ptp_remove(struct e1000_adapter * adapter)337 void e1000e_ptp_remove(struct e1000_adapter *adapter)
338 {
339 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
340 return;
341
342 cancel_delayed_work_sync(&adapter->systim_overflow_work);
343
344 if (adapter->ptp_clock) {
345 ptp_clock_unregister(adapter->ptp_clock);
346 adapter->ptp_clock = NULL;
347 e_info("removed PHC\n");
348 }
349 }
350