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_adjfine - adjust the frequency of the hardware clock
19 * @ptp: ptp clock structure
20 * @delta: Desired frequency chance in scaled parts per million
21 *
22 * Adjust the frequency of the PHC cycle counter by the indicated delta from
23 * the base frequency.
24 *
25 * Scaled parts per million is ppm but with a 16 bit binary fractional field.
26 **/
27static int e1000e_phc_adjfine(struct ptp_clock_info *ptp, long delta)
28{
29 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
30 ptp_clock_info);
31 struct e1000_hw *hw = &adapter->hw;
32 unsigned long flags;
33 u64 incvalue;
34 u32 timinca;
35 s32 ret_val;
36
37 /* Get the System Time Register SYSTIM base frequency */
38 ret_val = e1000e_get_base_timinca(adapter, timinca: &timinca);
39 if (ret_val)
40 return ret_val;
41
42 spin_lock_irqsave(&adapter->systim_lock, flags);
43
44 incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;
45 incvalue = adjust_by_scaled_ppm(base: incvalue, scaled_ppm: delta);
46
47 timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
48 timinca |= incvalue;
49
50 ew32(TIMINCA, timinca);
51
52 adapter->ptp_delta = delta;
53
54 spin_unlock_irqrestore(lock: &adapter->systim_lock, flags);
55
56 return 0;
57}
58
59/**
60 * e1000e_phc_adjtime - Shift the time of the hardware clock
61 * @ptp: ptp clock structure
62 * @delta: Desired change in nanoseconds
63 *
64 * Adjust the timer by resetting the timecounter structure.
65 **/
66static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
67{
68 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
69 ptp_clock_info);
70 unsigned long flags;
71
72 spin_lock_irqsave(&adapter->systim_lock, flags);
73 timecounter_adjtime(tc: &adapter->tc, delta);
74 spin_unlock_irqrestore(lock: &adapter->systim_lock, flags);
75
76 return 0;
77}
78
79#ifdef CONFIG_E1000E_HWTS
80#define MAX_HW_WAIT_COUNT (3)
81
82/**
83 * e1000e_phc_get_syncdevicetime - Callback given to timekeeping code reads system/device registers
84 * @device: current device time
85 * @system: system counter value read synchronously with device time
86 * @ctx: context provided by timekeeping code
87 *
88 * Read device and system (ART) clock simultaneously and return the corrected
89 * clock values in ns.
90 **/
91static int e1000e_phc_get_syncdevicetime(ktime_t *device,
92 struct system_counterval_t *system,
93 void *ctx)
94{
95 struct e1000_adapter *adapter = (struct e1000_adapter *)ctx;
96 struct e1000_hw *hw = &adapter->hw;
97 unsigned long flags;
98 int i;
99 u32 tsync_ctrl;
100 u64 dev_cycles;
101 u64 sys_cycles;
102
103 tsync_ctrl = er32(TSYNCTXCTL);
104 tsync_ctrl |= E1000_TSYNCTXCTL_START_SYNC |
105 E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK;
106 ew32(TSYNCTXCTL, tsync_ctrl);
107 for (i = 0; i < MAX_HW_WAIT_COUNT; ++i) {
108 udelay(usec: 1);
109 tsync_ctrl = er32(TSYNCTXCTL);
110 if (tsync_ctrl & E1000_TSYNCTXCTL_SYNC_COMP)
111 break;
112 }
113
114 if (i == MAX_HW_WAIT_COUNT)
115 return -ETIMEDOUT;
116
117 dev_cycles = er32(SYSSTMPH);
118 dev_cycles <<= 32;
119 dev_cycles |= er32(SYSSTMPL);
120 spin_lock_irqsave(&adapter->systim_lock, flags);
121 *device = ns_to_ktime(ns: timecounter_cyc2time(tc: &adapter->tc, cycle_tstamp: dev_cycles));
122 spin_unlock_irqrestore(lock: &adapter->systim_lock, flags);
123
124 sys_cycles = er32(PLTSTMPH);
125 sys_cycles <<= 32;
126 sys_cycles |= er32(PLTSTMPL);
127 system->cycles = sys_cycles;
128 system->cs_id = CSID_X86_ART;
129
130 return 0;
131}
132
133/**
134 * e1000e_phc_getcrosststamp - Reads the current system/device cross timestamp
135 * @ptp: ptp clock structure
136 * @xtstamp: structure containing timestamp
137 *
138 * Read device and system (ART) clock simultaneously and return the scaled
139 * clock values in ns.
140 **/
141static int e1000e_phc_getcrosststamp(struct ptp_clock_info *ptp,
142 struct system_device_crosststamp *xtstamp)
143{
144 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
145 ptp_clock_info);
146
147 return get_device_system_crosststamp(get_time_fn: e1000e_phc_get_syncdevicetime,
148 ctx: adapter, NULL, xtstamp);
149}
150#endif/*CONFIG_E1000E_HWTS*/
151
152/**
153 * e1000e_phc_gettimex - Reads the current time from the hardware clock and
154 * system clock
155 * @ptp: ptp clock structure
156 * @ts: timespec structure to hold the current PHC time
157 * @sts: structure to hold the current system time
158 *
159 * Read the timecounter and return the correct value in ns after converting
160 * it into a struct timespec.
161 **/
162static int e1000e_phc_gettimex(struct ptp_clock_info *ptp,
163 struct timespec64 *ts,
164 struct ptp_system_timestamp *sts)
165{
166 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
167 ptp_clock_info);
168 unsigned long flags;
169 u64 cycles, ns;
170
171 spin_lock_irqsave(&adapter->systim_lock, flags);
172
173 /* NOTE: Non-monotonic SYSTIM readings may be returned */
174 cycles = e1000e_read_systim(adapter, sts);
175 ns = timecounter_cyc2time(tc: &adapter->tc, cycle_tstamp: cycles);
176
177 spin_unlock_irqrestore(lock: &adapter->systim_lock, flags);
178
179 *ts = ns_to_timespec64(nsec: ns);
180
181 return 0;
182}
183
184/**
185 * e1000e_phc_settime - Set the current time on the hardware clock
186 * @ptp: ptp clock structure
187 * @ts: timespec containing the new time for the cycle counter
188 *
189 * Reset the timecounter to use a new base value instead of the kernel
190 * wall timer value.
191 **/
192static int e1000e_phc_settime(struct ptp_clock_info *ptp,
193 const struct timespec64 *ts)
194{
195 struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
196 ptp_clock_info);
197 unsigned long flags;
198 u64 ns;
199
200 ns = timespec64_to_ns(ts);
201
202 /* reset the timecounter */
203 spin_lock_irqsave(&adapter->systim_lock, flags);
204 timecounter_init(tc: &adapter->tc, cc: &adapter->cc, start_tstamp: ns);
205 spin_unlock_irqrestore(lock: &adapter->systim_lock, flags);
206
207 return 0;
208}
209
210/**
211 * e1000e_phc_enable - enable or disable an ancillary feature
212 * @ptp: ptp clock structure
213 * @request: Desired resource to enable or disable
214 * @on: Caller passes one to enable or zero to disable
215 *
216 * Enable (or disable) ancillary features of the PHC subsystem.
217 * Currently, no ancillary features are supported.
218 **/
219static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
220 struct ptp_clock_request __always_unused *request,
221 int __always_unused on)
222{
223 return -EOPNOTSUPP;
224}
225
226static void e1000e_systim_overflow_work(struct work_struct *work)
227{
228 struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
229 systim_overflow_work.work);
230 struct e1000_hw *hw = &adapter->hw;
231 struct timespec64 ts;
232 u64 ns;
233
234 /* Update the timecounter */
235 ns = timecounter_read(tc: &adapter->tc);
236
237 ts = ns_to_timespec64(nsec: ns);
238 e_dbg("SYSTIM overflow check at %lld.%09lu\n",
239 (long long) ts.tv_sec, ts.tv_nsec);
240
241 schedule_delayed_work(dwork: &adapter->systim_overflow_work,
242 E1000_SYSTIM_OVERFLOW_PERIOD);
243}
244
245static const struct ptp_clock_info e1000e_ptp_clock_info = {
246 .owner = THIS_MODULE,
247 .n_alarm = 0,
248 .n_ext_ts = 0,
249 .n_per_out = 0,
250 .n_pins = 0,
251 .pps = 0,
252 .adjfine = e1000e_phc_adjfine,
253 .adjtime = e1000e_phc_adjtime,
254 .gettimex64 = e1000e_phc_gettimex,
255 .settime64 = e1000e_phc_settime,
256 .enable = e1000e_phc_enable,
257};
258
259/**
260 * e1000e_ptp_init - initialize PTP for devices which support it
261 * @adapter: board private structure
262 *
263 * This function performs the required steps for enabling PTP support.
264 * If PTP support has already been loaded it simply calls the cyclecounter
265 * init routine and exits.
266 **/
267void e1000e_ptp_init(struct e1000_adapter *adapter)
268{
269 struct e1000_hw *hw = &adapter->hw;
270
271 adapter->ptp_clock = NULL;
272
273 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
274 return;
275
276 adapter->ptp_clock_info = e1000e_ptp_clock_info;
277
278 snprintf(buf: adapter->ptp_clock_info.name,
279 size: sizeof(adapter->ptp_clock_info.name), fmt: "%pm",
280 adapter->netdev->perm_addr);
281
282 switch (hw->mac.type) {
283 case e1000_pch2lan:
284 adapter->ptp_clock_info.max_adj = MAX_PPB_96MHZ;
285 break;
286 case e1000_pch_lpt:
287 if (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)
288 adapter->ptp_clock_info.max_adj = MAX_PPB_96MHZ;
289 else
290 adapter->ptp_clock_info.max_adj = MAX_PPB_25MHZ;
291 break;
292 case e1000_pch_spt:
293 adapter->ptp_clock_info.max_adj = MAX_PPB_24MHZ;
294 break;
295 case e1000_pch_cnp:
296 case e1000_pch_tgp:
297 case e1000_pch_adp:
298 case e1000_pch_nvp:
299 if (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)
300 adapter->ptp_clock_info.max_adj = MAX_PPB_24MHZ;
301 else
302 adapter->ptp_clock_info.max_adj = MAX_PPB_38400KHZ;
303 break;
304 case e1000_pch_mtp:
305 case e1000_pch_lnp:
306 case e1000_pch_ptp:
307 adapter->ptp_clock_info.max_adj = MAX_PPB_38400KHZ;
308 break;
309 case e1000_82574:
310 case e1000_82583:
311 adapter->ptp_clock_info.max_adj = MAX_PPB_25MHZ;
312 break;
313 default:
314 break;
315 }
316
317#ifdef CONFIG_E1000E_HWTS
318 /* CPU must have ART and GBe must be from Sunrise Point or greater */
319 if (hw->mac.type >= e1000_pch_spt && boot_cpu_has(X86_FEATURE_ART))
320 adapter->ptp_clock_info.getcrosststamp =
321 e1000e_phc_getcrosststamp;
322#endif/*CONFIG_E1000E_HWTS*/
323
324 INIT_DELAYED_WORK(&adapter->systim_overflow_work,
325 e1000e_systim_overflow_work);
326
327 schedule_delayed_work(dwork: &adapter->systim_overflow_work,
328 E1000_SYSTIM_OVERFLOW_PERIOD);
329
330 adapter->ptp_clock = ptp_clock_register(info: &adapter->ptp_clock_info,
331 parent: &adapter->pdev->dev);
332 if (IS_ERR(ptr: adapter->ptp_clock)) {
333 adapter->ptp_clock = NULL;
334 e_err("ptp_clock_register failed\n");
335 } else if (adapter->ptp_clock) {
336 e_info("registered PHC clock\n");
337 }
338}
339
340/**
341 * e1000e_ptp_remove - disable PTP device and stop the overflow check
342 * @adapter: board private structure
343 *
344 * Stop the PTP support, and cancel the delayed work.
345 **/
346void e1000e_ptp_remove(struct e1000_adapter *adapter)
347{
348 if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
349 return;
350
351 cancel_delayed_work_sync(dwork: &adapter->systim_overflow_work);
352
353 if (adapter->ptp_clock) {
354 ptp_clock_unregister(ptp: adapter->ptp_clock);
355 adapter->ptp_clock = NULL;
356 e_info("removed PHC\n");
357 }
358}
359