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_gettimex - Reads the current time from the hardware clock and
165 * system clock
166 * @ptp: ptp clock structure
167 * @ts: timespec structure to hold the current PHC time
168 * @sts: structure to hold the current system time
169 *
170 * Read the timecounter and return the correct value in ns after converting
171 * it into a struct timespec.
172 **/
e1000e_phc_gettimex(struct ptp_clock_info * ptp,struct timespec64 * ts,struct ptp_system_timestamp * sts)173 static int e1000e_phc_gettimex(struct ptp_clock_info *ptp,
174 struct timespec64 *ts,
175 struct ptp_system_timestamp *sts)
176 {
177 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
178 ptp_clock_info);
179 unsigned long flags;
180 u64 cycles, ns;
181
182 spin_lock_irqsave(&adapter->systim_lock, flags);
183
184 /* NOTE: Non-monotonic SYSTIM readings may be returned */
185 cycles = e1000e_read_systim(adapter, sts);
186 ns = timecounter_cyc2time(&adapter->tc, cycles);
187
188 spin_unlock_irqrestore(&adapter->systim_lock, flags);
189
190 *ts = ns_to_timespec64(ns);
191
192 return 0;
193 }
194
195 /**
196 * e1000e_phc_settime - Set the current time on the hardware clock
197 * @ptp: ptp clock structure
198 * @ts: timespec containing the new time for the cycle counter
199 *
200 * Reset the timecounter to use a new base value instead of the kernel
201 * wall timer value.
202 **/
e1000e_phc_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)203 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
204 const struct timespec64 *ts)
205 {
206 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
207 ptp_clock_info);
208 unsigned long flags;
209 u64 ns;
210
211 ns = timespec64_to_ns(ts);
212
213 /* reset the timecounter */
214 spin_lock_irqsave(&adapter->systim_lock, flags);
215 timecounter_init(&adapter->tc, &adapter->cc, ns);
216 spin_unlock_irqrestore(&adapter->systim_lock, flags);
217
218 return 0;
219 }
220
221 /**
222 * e1000e_phc_enable - enable or disable an ancillary feature
223 * @ptp: ptp clock structure
224 * @request: Desired resource to enable or disable
225 * @on: Caller passes one to enable or zero to disable
226 *
227 * Enable (or disable) ancillary features of the PHC subsystem.
228 * Currently, no ancillary features are supported.
229 **/
e1000e_phc_enable(struct ptp_clock_info __always_unused * ptp,struct ptp_clock_request __always_unused * request,int __always_unused on)230 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
231 struct ptp_clock_request __always_unused *request,
232 int __always_unused on)
233 {
234 return -EOPNOTSUPP;
235 }
236
e1000e_systim_overflow_work(struct work_struct * work)237 static void e1000e_systim_overflow_work(struct work_struct *work)
238 {
239 struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
240 systim_overflow_work.work);
241 struct e1000_hw *hw = &adapter->hw;
242 struct timespec64 ts;
243 u64 ns;
244
245 /* Update the timecounter */
246 ns = timecounter_read(&adapter->tc);
247
248 ts = ns_to_timespec64(ns);
249 e_dbg("SYSTIM overflow check at %lld.%09lu\n",
250 (long long) ts.tv_sec, ts.tv_nsec);
251
252 schedule_delayed_work(&adapter->systim_overflow_work,
253 E1000_SYSTIM_OVERFLOW_PERIOD);
254 }
255
256 static const struct ptp_clock_info e1000e_ptp_clock_info = {
257 .owner = THIS_MODULE,
258 .n_alarm = 0,
259 .n_ext_ts = 0,
260 .n_per_out = 0,
261 .n_pins = 0,
262 .pps = 0,
263 .adjfreq = e1000e_phc_adjfreq,
264 .adjtime = e1000e_phc_adjtime,
265 .gettimex64 = e1000e_phc_gettimex,
266 .settime64 = e1000e_phc_settime,
267 .enable = e1000e_phc_enable,
268 };
269
270 /**
271 * e1000e_ptp_init - initialize PTP for devices which support it
272 * @adapter: board private structure
273 *
274 * This function performs the required steps for enabling PTP support.
275 * If PTP support has already been loaded it simply calls the cyclecounter
276 * init routine and exits.
277 **/
e1000e_ptp_init(struct e1000_adapter * adapter)278 void e1000e_ptp_init(struct e1000_adapter *adapter)
279 {
280 struct e1000_hw *hw = &adapter->hw;
281
282 adapter->ptp_clock = NULL;
283
284 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
285 return;
286
287 adapter->ptp_clock_info = e1000e_ptp_clock_info;
288
289 snprintf(adapter->ptp_clock_info.name,
290 sizeof(adapter->ptp_clock_info.name), "%pm",
291 adapter->netdev->perm_addr);
292
293 switch (hw->mac.type) {
294 case e1000_pch2lan:
295 case e1000_pch_lpt:
296 case e1000_pch_spt:
297 case e1000_pch_cnp:
298 if ((hw->mac.type < e1000_pch_lpt) ||
299 (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
300 adapter->ptp_clock_info.max_adj = 24000000 - 1;
301 break;
302 }
303 /* fall-through */
304 case e1000_82574:
305 case e1000_82583:
306 adapter->ptp_clock_info.max_adj = 600000000 - 1;
307 break;
308 default:
309 break;
310 }
311
312 #ifdef CONFIG_E1000E_HWTS
313 /* CPU must have ART and GBe must be from Sunrise Point or greater */
314 if (hw->mac.type >= e1000_pch_spt && boot_cpu_has(X86_FEATURE_ART))
315 adapter->ptp_clock_info.getcrosststamp =
316 e1000e_phc_getcrosststamp;
317 #endif/*CONFIG_E1000E_HWTS*/
318
319 INIT_DELAYED_WORK(&adapter->systim_overflow_work,
320 e1000e_systim_overflow_work);
321
322 schedule_delayed_work(&adapter->systim_overflow_work,
323 E1000_SYSTIM_OVERFLOW_PERIOD);
324
325 adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
326 &adapter->pdev->dev);
327 if (IS_ERR(adapter->ptp_clock)) {
328 adapter->ptp_clock = NULL;
329 e_err("ptp_clock_register failed\n");
330 } else if (adapter->ptp_clock) {
331 e_info("registered PHC clock\n");
332 }
333 }
334
335 /**
336 * e1000e_ptp_remove - disable PTP device and stop the overflow check
337 * @adapter: board private structure
338 *
339 * Stop the PTP support, and cancel the delayed work.
340 **/
e1000e_ptp_remove(struct e1000_adapter * adapter)341 void e1000e_ptp_remove(struct e1000_adapter *adapter)
342 {
343 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
344 return;
345
346 cancel_delayed_work_sync(&adapter->systim_overflow_work);
347
348 if (adapter->ptp_clock) {
349 ptp_clock_unregister(adapter->ptp_clock);
350 adapter->ptp_clock = NULL;
351 e_info("removed PHC\n");
352 }
353 }
354
