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v6.13.7
  1// SPDX-License-Identifier: (GPL-2.0 OR MIT)
  2/*
  3 * DSA driver for:
  4 * Hirschmann Hellcreek TSN switch.
  5 *
  6 * Copyright (C) 2019,2020 Hochschule Offenburg
  7 * Copyright (C) 2019,2020 Linutronix GmbH
  8 * Authors: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
  9 *	    Kurt Kanzenbach <kurt@linutronix.de>
 10 */
 11
 12#include <linux/of.h>
 13#include <linux/ptp_clock_kernel.h>
 14#include "hellcreek.h"
 15#include "hellcreek_ptp.h"
 16#include "hellcreek_hwtstamp.h"
 17
 18u16 hellcreek_ptp_read(struct hellcreek *hellcreek, unsigned int offset)
 19{
 20	return readw(hellcreek->ptp_base + offset);
 21}
 22
 23void hellcreek_ptp_write(struct hellcreek *hellcreek, u16 data,
 24			 unsigned int offset)
 25{
 26	writew(data, hellcreek->ptp_base + offset);
 27}
 28
 29/* Get nanoseconds from PTP clock */
 30static u64 hellcreek_ptp_clock_read(struct hellcreek *hellcreek,
 31				    struct ptp_system_timestamp *sts)
 32{
 33	u16 nsl, nsh;
 34
 35	/* Take a snapshot */
 36	hellcreek_ptp_write(hellcreek, PR_COMMAND_C_SS, PR_COMMAND_C);
 37
 38	/* The time of the day is saved as 96 bits. However, due to hardware
 39	 * limitations the seconds are not or only partly kept in the PTP
 40	 * core. Currently only three bits for the seconds are available. That's
 41	 * why only the nanoseconds are used and the seconds are tracked in
 42	 * software. Anyway due to internal locking all five registers should be
 43	 * read.
 44	 */
 45	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 46	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 47	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 48	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 49	ptp_read_system_prets(sts);
 50	nsl = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 51	ptp_read_system_postts(sts);
 52
 53	return (u64)nsl | ((u64)nsh << 16);
 54}
 55
 56static u64 __hellcreek_ptp_gettime(struct hellcreek *hellcreek,
 57				   struct ptp_system_timestamp *sts)
 58{
 59	u64 ns;
 60
 61	ns = hellcreek_ptp_clock_read(hellcreek, sts);
 62	if (ns < hellcreek->last_ts)
 63		hellcreek->seconds++;
 64	hellcreek->last_ts = ns;
 65	ns += hellcreek->seconds * NSEC_PER_SEC;
 66
 67	return ns;
 68}
 69
 70/* Retrieve the seconds parts in nanoseconds for a packet timestamped with @ns.
 71 * There has to be a check whether an overflow occurred between the packet
 72 * arrival and now. If so use the correct seconds (-1) for calculating the
 73 * packet arrival time.
 74 */
 75u64 hellcreek_ptp_gettime_seconds(struct hellcreek *hellcreek, u64 ns)
 76{
 77	u64 s;
 78
 79	__hellcreek_ptp_gettime(hellcreek, NULL);
 80	if (hellcreek->last_ts > ns)
 81		s = hellcreek->seconds * NSEC_PER_SEC;
 82	else
 83		s = (hellcreek->seconds - 1) * NSEC_PER_SEC;
 84
 85	return s;
 86}
 87
 88static int hellcreek_ptp_gettimex(struct ptp_clock_info *ptp,
 89				  struct timespec64 *ts,
 90				  struct ptp_system_timestamp *sts)
 91{
 92	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
 93	u64 ns;
 94
 95	mutex_lock(&hellcreek->ptp_lock);
 96	ns = __hellcreek_ptp_gettime(hellcreek, sts);
 97	mutex_unlock(&hellcreek->ptp_lock);
 98
 99	*ts = ns_to_timespec64(ns);
100
101	return 0;
102}
103
104static int hellcreek_ptp_settime(struct ptp_clock_info *ptp,
105				 const struct timespec64 *ts)
106{
107	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
108	u16 secl, nsh, nsl;
109
110	secl = ts->tv_sec & 0xffff;
111	nsh  = ((u32)ts->tv_nsec & 0xffff0000) >> 16;
112	nsl  = ts->tv_nsec & 0xffff;
113
114	mutex_lock(&hellcreek->ptp_lock);
115
116	/* Update overflow data structure */
117	hellcreek->seconds = ts->tv_sec;
118	hellcreek->last_ts = ts->tv_nsec;
119
120	/* Set time in clock */
121	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
122	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
123	hellcreek_ptp_write(hellcreek, secl, PR_CLOCK_WRITE_C);
124	hellcreek_ptp_write(hellcreek, nsh,  PR_CLOCK_WRITE_C);
125	hellcreek_ptp_write(hellcreek, nsl,  PR_CLOCK_WRITE_C);
126
127	mutex_unlock(&hellcreek->ptp_lock);
128
129	return 0;
130}
131
132static int hellcreek_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
133{
134	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
135	u16 negative = 0, addendh, addendl;
136	u32 addend;
137	u64 adj;
138
139	if (scaled_ppm < 0) {
140		negative = 1;
141		scaled_ppm = -scaled_ppm;
142	}
143
144	/* IP-Core adjusts the nominal frequency by adding or subtracting 1 ns
145	 * from the 8 ns (period of the oscillator) every time the accumulator
146	 * register overflows. The value stored in the addend register is added
147	 * to the accumulator register every 8 ns.
148	 *
149	 * addend value = (2^30 * accumulator_overflow_rate) /
150	 *                oscillator_frequency
151	 * where:
152	 *
153	 * oscillator_frequency = 125 MHz
154	 * accumulator_overflow_rate = 125 MHz * scaled_ppm * 2^-16 * 10^-6 * 8
155	 */
156	adj = scaled_ppm;
157	adj <<= 11;
158	addend = (u32)div_u64(adj, 15625);
159
160	addendh = (addend & 0xffff0000) >> 16;
161	addendl = addend & 0xffff;
162
163	negative = (negative << 15) & 0x8000;
164
165	mutex_lock(&hellcreek->ptp_lock);
166
167	/* Set drift register */
168	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_DRIFT_C);
169	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
170	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
171	hellcreek_ptp_write(hellcreek, addendh,  PR_CLOCK_DRIFT_C);
172	hellcreek_ptp_write(hellcreek, addendl,  PR_CLOCK_DRIFT_C);
173
174	mutex_unlock(&hellcreek->ptp_lock);
175
176	return 0;
177}
178
179static int hellcreek_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
180{
181	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
182	u16 negative = 0, counth, countl;
183	u32 count_val;
184
185	/* If the offset is larger than IP-Core slow offset resources. Don't
186	 * consider slow adjustment. Rather, add the offset directly to the
187	 * current time
188	 */
189	if (abs(delta) > MAX_SLOW_OFFSET_ADJ) {
190		struct timespec64 now, then = ns_to_timespec64(delta);
191
192		hellcreek_ptp_gettimex(ptp, &now, NULL);
193		now = timespec64_add(now, then);
194		hellcreek_ptp_settime(ptp, &now);
195
196		return 0;
197	}
198
199	if (delta < 0) {
200		negative = 1;
201		delta = -delta;
202	}
203
204	/* 'count_val' does not exceed the maximum register size (2^30) */
205	count_val = div_s64(delta, MAX_NS_PER_STEP);
206
207	counth = (count_val & 0xffff0000) >> 16;
208	countl = count_val & 0xffff;
209
210	negative = (negative << 15) & 0x8000;
211
212	mutex_lock(&hellcreek->ptp_lock);
213
214	/* Set offset write register */
215	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_OFFSET_C);
216	hellcreek_ptp_write(hellcreek, MAX_NS_PER_STEP, PR_CLOCK_OFFSET_C);
217	hellcreek_ptp_write(hellcreek, MIN_CLK_CYCLES_BETWEEN_STEPS,
218			    PR_CLOCK_OFFSET_C);
219	hellcreek_ptp_write(hellcreek, countl,  PR_CLOCK_OFFSET_C);
220	hellcreek_ptp_write(hellcreek, counth,  PR_CLOCK_OFFSET_C);
221
222	mutex_unlock(&hellcreek->ptp_lock);
223
224	return 0;
225}
226
227static int hellcreek_ptp_enable(struct ptp_clock_info *ptp,
228				struct ptp_clock_request *rq, int on)
229{
230	return -EOPNOTSUPP;
231}
232
233static void hellcreek_ptp_overflow_check(struct work_struct *work)
234{
235	struct delayed_work *dw = to_delayed_work(work);
236	struct hellcreek *hellcreek;
237
238	hellcreek = dw_overflow_to_hellcreek(dw);
239
240	mutex_lock(&hellcreek->ptp_lock);
241	__hellcreek_ptp_gettime(hellcreek, NULL);
242	mutex_unlock(&hellcreek->ptp_lock);
243
244	schedule_delayed_work(&hellcreek->overflow_work,
245			      HELLCREEK_OVERFLOW_PERIOD);
246}
247
248static enum led_brightness hellcreek_get_brightness(struct hellcreek *hellcreek,
249						    int led)
250{
251	return (hellcreek->status_out & led) ? 1 : 0;
252}
253
254static void hellcreek_set_brightness(struct hellcreek *hellcreek, int led,
255				     enum led_brightness b)
256{
257	mutex_lock(&hellcreek->ptp_lock);
258
259	if (b)
260		hellcreek->status_out |= led;
261	else
262		hellcreek->status_out &= ~led;
263
264	hellcreek_ptp_write(hellcreek, hellcreek->status_out, STATUS_OUT);
265
266	mutex_unlock(&hellcreek->ptp_lock);
267}
268
269static void hellcreek_led_sync_good_set(struct led_classdev *ldev,
270					enum led_brightness b)
271{
272	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
273
274	hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, b);
275}
276
277static enum led_brightness hellcreek_led_sync_good_get(struct led_classdev *ldev)
278{
279	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
280
281	return hellcreek_get_brightness(hellcreek, STATUS_OUT_SYNC_GOOD);
282}
283
284static void hellcreek_led_is_gm_set(struct led_classdev *ldev,
285				    enum led_brightness b)
286{
287	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
288
289	hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, b);
290}
291
292static enum led_brightness hellcreek_led_is_gm_get(struct led_classdev *ldev)
293{
294	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
295
296	return hellcreek_get_brightness(hellcreek, STATUS_OUT_IS_GM);
297}
298
299/* There two available LEDs internally called sync_good and is_gm. However, the
300 * user might want to use a different label and specify the default state. Take
301 * those properties from device tree.
302 */
303static int hellcreek_led_setup(struct hellcreek *hellcreek)
304{
305	struct device_node *leds, *led = NULL;
306	enum led_default_state state;
307	const char *label;
308	int ret = -EINVAL;
309
310	of_node_get(hellcreek->dev->of_node);
311	leds = of_find_node_by_name(hellcreek->dev->of_node, "leds");
312	if (!leds) {
313		dev_err(hellcreek->dev, "No LEDs specified in device tree!\n");
314		return ret;
315	}
316
317	hellcreek->status_out = 0;
318
319	led = of_get_next_available_child(leds, led);
320	if (!led) {
321		dev_err(hellcreek->dev, "First LED not specified!\n");
322		goto out;
323	}
324
325	ret = of_property_read_string(led, "label", &label);
326	hellcreek->led_sync_good.name = ret ? "sync_good" : label;
327
328	state = led_init_default_state_get(of_fwnode_handle(led));
329	switch (state) {
330	case LEDS_DEFSTATE_ON:
331		hellcreek->led_sync_good.brightness = 1;
332		break;
333	case LEDS_DEFSTATE_KEEP:
334		hellcreek->led_sync_good.brightness =
335			hellcreek_get_brightness(hellcreek, STATUS_OUT_SYNC_GOOD);
336		break;
337	default:
338		hellcreek->led_sync_good.brightness = 0;
339	}
340
341	hellcreek->led_sync_good.max_brightness = 1;
342	hellcreek->led_sync_good.brightness_set = hellcreek_led_sync_good_set;
343	hellcreek->led_sync_good.brightness_get = hellcreek_led_sync_good_get;
344
345	led = of_get_next_available_child(leds, led);
346	if (!led) {
347		dev_err(hellcreek->dev, "Second LED not specified!\n");
348		ret = -EINVAL;
349		goto out;
350	}
351
352	ret = of_property_read_string(led, "label", &label);
353	hellcreek->led_is_gm.name = ret ? "is_gm" : label;
354
355	state = led_init_default_state_get(of_fwnode_handle(led));
356	switch (state) {
357	case LEDS_DEFSTATE_ON:
358		hellcreek->led_is_gm.brightness = 1;
359		break;
360	case LEDS_DEFSTATE_KEEP:
361		hellcreek->led_is_gm.brightness =
362			hellcreek_get_brightness(hellcreek, STATUS_OUT_IS_GM);
363		break;
364	default:
365		hellcreek->led_is_gm.brightness = 0;
366	}
367
368	hellcreek->led_is_gm.max_brightness = 1;
369	hellcreek->led_is_gm.brightness_set = hellcreek_led_is_gm_set;
370	hellcreek->led_is_gm.brightness_get = hellcreek_led_is_gm_get;
371
372	/* Set initial state */
373	if (hellcreek->led_sync_good.brightness == 1)
374		hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, 1);
375	if (hellcreek->led_is_gm.brightness == 1)
376		hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, 1);
377
378	/* Register both leds */
379	led_classdev_register(hellcreek->dev, &hellcreek->led_sync_good);
380	led_classdev_register(hellcreek->dev, &hellcreek->led_is_gm);
381
382	ret = 0;
383
384out:
385	of_node_put(leds);
386
387	return ret;
388}
389
390int hellcreek_ptp_setup(struct hellcreek *hellcreek)
391{
392	u16 status;
393	int ret;
394
395	/* Set up the overflow work */
396	INIT_DELAYED_WORK(&hellcreek->overflow_work,
397			  hellcreek_ptp_overflow_check);
398
399	/* Setup PTP clock */
400	hellcreek->ptp_clock_info.owner = THIS_MODULE;
401	snprintf(hellcreek->ptp_clock_info.name,
402		 sizeof(hellcreek->ptp_clock_info.name),
403		 dev_name(hellcreek->dev));
404
405	/* IP-Core can add up to 0.5 ns per 8 ns cycle, which means
406	 * accumulator_overflow_rate shall not exceed 62.5 MHz (which adjusts
407	 * the nominal frequency by 6.25%)
408	 */
409	hellcreek->ptp_clock_info.max_adj     = 62500000;
410	hellcreek->ptp_clock_info.n_alarm     = 0;
411	hellcreek->ptp_clock_info.n_pins      = 0;
412	hellcreek->ptp_clock_info.n_ext_ts    = 0;
413	hellcreek->ptp_clock_info.n_per_out   = 0;
414	hellcreek->ptp_clock_info.pps	      = 0;
415	hellcreek->ptp_clock_info.adjfine     = hellcreek_ptp_adjfine;
416	hellcreek->ptp_clock_info.adjtime     = hellcreek_ptp_adjtime;
417	hellcreek->ptp_clock_info.gettimex64  = hellcreek_ptp_gettimex;
418	hellcreek->ptp_clock_info.settime64   = hellcreek_ptp_settime;
419	hellcreek->ptp_clock_info.enable      = hellcreek_ptp_enable;
420	hellcreek->ptp_clock_info.do_aux_work = hellcreek_hwtstamp_work;
421
422	hellcreek->ptp_clock = ptp_clock_register(&hellcreek->ptp_clock_info,
423						  hellcreek->dev);
424	if (IS_ERR(hellcreek->ptp_clock))
425		return PTR_ERR(hellcreek->ptp_clock);
426
427	/* Enable the offset correction process, if no offset correction is
428	 * already taking place
429	 */
430	status = hellcreek_ptp_read(hellcreek, PR_CLOCK_STATUS_C);
431	if (!(status & PR_CLOCK_STATUS_C_OFS_ACT))
432		hellcreek_ptp_write(hellcreek,
433				    status | PR_CLOCK_STATUS_C_ENA_OFS,
434				    PR_CLOCK_STATUS_C);
435
436	/* Enable the drift correction process */
437	hellcreek_ptp_write(hellcreek, status | PR_CLOCK_STATUS_C_ENA_DRIFT,
438			    PR_CLOCK_STATUS_C);
439
440	/* LED setup */
441	ret = hellcreek_led_setup(hellcreek);
442	if (ret) {
443		if (hellcreek->ptp_clock)
444			ptp_clock_unregister(hellcreek->ptp_clock);
445		return ret;
446	}
447
448	schedule_delayed_work(&hellcreek->overflow_work,
449			      HELLCREEK_OVERFLOW_PERIOD);
450
451	return 0;
452}
453
454void hellcreek_ptp_free(struct hellcreek *hellcreek)
455{
456	led_classdev_unregister(&hellcreek->led_is_gm);
457	led_classdev_unregister(&hellcreek->led_sync_good);
458	cancel_delayed_work_sync(&hellcreek->overflow_work);
459	if (hellcreek->ptp_clock)
460		ptp_clock_unregister(hellcreek->ptp_clock);
461	hellcreek->ptp_clock = NULL;
462}
v5.14.15
  1// SPDX-License-Identifier: (GPL-2.0 OR MIT)
  2/*
  3 * DSA driver for:
  4 * Hirschmann Hellcreek TSN switch.
  5 *
  6 * Copyright (C) 2019,2020 Hochschule Offenburg
  7 * Copyright (C) 2019,2020 Linutronix GmbH
  8 * Authors: Kamil Alkhouri <kamil.alkhouri@hs-offenburg.de>
  9 *	    Kurt Kanzenbach <kurt@linutronix.de>
 10 */
 11
 
 12#include <linux/ptp_clock_kernel.h>
 13#include "hellcreek.h"
 14#include "hellcreek_ptp.h"
 15#include "hellcreek_hwtstamp.h"
 16
 17u16 hellcreek_ptp_read(struct hellcreek *hellcreek, unsigned int offset)
 18{
 19	return readw(hellcreek->ptp_base + offset);
 20}
 21
 22void hellcreek_ptp_write(struct hellcreek *hellcreek, u16 data,
 23			 unsigned int offset)
 24{
 25	writew(data, hellcreek->ptp_base + offset);
 26}
 27
 28/* Get nanoseconds from PTP clock */
 29static u64 hellcreek_ptp_clock_read(struct hellcreek *hellcreek)
 
 30{
 31	u16 nsl, nsh;
 32
 33	/* Take a snapshot */
 34	hellcreek_ptp_write(hellcreek, PR_COMMAND_C_SS, PR_COMMAND_C);
 35
 36	/* The time of the day is saved as 96 bits. However, due to hardware
 37	 * limitations the seconds are not or only partly kept in the PTP
 38	 * core. Currently only three bits for the seconds are available. That's
 39	 * why only the nanoseconds are used and the seconds are tracked in
 40	 * software. Anyway due to internal locking all five registers should be
 41	 * read.
 42	 */
 43	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 44	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 45	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 46	nsh = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 
 47	nsl = hellcreek_ptp_read(hellcreek, PR_SS_SYNC_DATA_C);
 
 48
 49	return (u64)nsl | ((u64)nsh << 16);
 50}
 51
 52static u64 __hellcreek_ptp_gettime(struct hellcreek *hellcreek)
 
 53{
 54	u64 ns;
 55
 56	ns = hellcreek_ptp_clock_read(hellcreek);
 57	if (ns < hellcreek->last_ts)
 58		hellcreek->seconds++;
 59	hellcreek->last_ts = ns;
 60	ns += hellcreek->seconds * NSEC_PER_SEC;
 61
 62	return ns;
 63}
 64
 65/* Retrieve the seconds parts in nanoseconds for a packet timestamped with @ns.
 66 * There has to be a check whether an overflow occurred between the packet
 67 * arrival and now. If so use the correct seconds (-1) for calculating the
 68 * packet arrival time.
 69 */
 70u64 hellcreek_ptp_gettime_seconds(struct hellcreek *hellcreek, u64 ns)
 71{
 72	u64 s;
 73
 74	__hellcreek_ptp_gettime(hellcreek);
 75	if (hellcreek->last_ts > ns)
 76		s = hellcreek->seconds * NSEC_PER_SEC;
 77	else
 78		s = (hellcreek->seconds - 1) * NSEC_PER_SEC;
 79
 80	return s;
 81}
 82
 83static int hellcreek_ptp_gettime(struct ptp_clock_info *ptp,
 84				 struct timespec64 *ts)
 
 85{
 86	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
 87	u64 ns;
 88
 89	mutex_lock(&hellcreek->ptp_lock);
 90	ns = __hellcreek_ptp_gettime(hellcreek);
 91	mutex_unlock(&hellcreek->ptp_lock);
 92
 93	*ts = ns_to_timespec64(ns);
 94
 95	return 0;
 96}
 97
 98static int hellcreek_ptp_settime(struct ptp_clock_info *ptp,
 99				 const struct timespec64 *ts)
100{
101	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
102	u16 secl, nsh, nsl;
103
104	secl = ts->tv_sec & 0xffff;
105	nsh  = ((u32)ts->tv_nsec & 0xffff0000) >> 16;
106	nsl  = ts->tv_nsec & 0xffff;
107
108	mutex_lock(&hellcreek->ptp_lock);
109
110	/* Update overflow data structure */
111	hellcreek->seconds = ts->tv_sec;
112	hellcreek->last_ts = ts->tv_nsec;
113
114	/* Set time in clock */
115	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
116	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_WRITE_C);
117	hellcreek_ptp_write(hellcreek, secl, PR_CLOCK_WRITE_C);
118	hellcreek_ptp_write(hellcreek, nsh,  PR_CLOCK_WRITE_C);
119	hellcreek_ptp_write(hellcreek, nsl,  PR_CLOCK_WRITE_C);
120
121	mutex_unlock(&hellcreek->ptp_lock);
122
123	return 0;
124}
125
126static int hellcreek_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
127{
128	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
129	u16 negative = 0, addendh, addendl;
130	u32 addend;
131	u64 adj;
132
133	if (scaled_ppm < 0) {
134		negative = 1;
135		scaled_ppm = -scaled_ppm;
136	}
137
138	/* IP-Core adjusts the nominal frequency by adding or subtracting 1 ns
139	 * from the 8 ns (period of the oscillator) every time the accumulator
140	 * register overflows. The value stored in the addend register is added
141	 * to the accumulator register every 8 ns.
142	 *
143	 * addend value = (2^30 * accumulator_overflow_rate) /
144	 *                oscillator_frequency
145	 * where:
146	 *
147	 * oscillator_frequency = 125 MHz
148	 * accumulator_overflow_rate = 125 MHz * scaled_ppm * 2^-16 * 10^-6 * 8
149	 */
150	adj = scaled_ppm;
151	adj <<= 11;
152	addend = (u32)div_u64(adj, 15625);
153
154	addendh = (addend & 0xffff0000) >> 16;
155	addendl = addend & 0xffff;
156
157	negative = (negative << 15) & 0x8000;
158
159	mutex_lock(&hellcreek->ptp_lock);
160
161	/* Set drift register */
162	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_DRIFT_C);
163	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
164	hellcreek_ptp_write(hellcreek, 0x00, PR_CLOCK_DRIFT_C);
165	hellcreek_ptp_write(hellcreek, addendh,  PR_CLOCK_DRIFT_C);
166	hellcreek_ptp_write(hellcreek, addendl,  PR_CLOCK_DRIFT_C);
167
168	mutex_unlock(&hellcreek->ptp_lock);
169
170	return 0;
171}
172
173static int hellcreek_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
174{
175	struct hellcreek *hellcreek = ptp_to_hellcreek(ptp);
176	u16 negative = 0, counth, countl;
177	u32 count_val;
178
179	/* If the offset is larger than IP-Core slow offset resources. Don't
180	 * consider slow adjustment. Rather, add the offset directly to the
181	 * current time
182	 */
183	if (abs(delta) > MAX_SLOW_OFFSET_ADJ) {
184		struct timespec64 now, then = ns_to_timespec64(delta);
185
186		hellcreek_ptp_gettime(ptp, &now);
187		now = timespec64_add(now, then);
188		hellcreek_ptp_settime(ptp, &now);
189
190		return 0;
191	}
192
193	if (delta < 0) {
194		negative = 1;
195		delta = -delta;
196	}
197
198	/* 'count_val' does not exceed the maximum register size (2^30) */
199	count_val = div_s64(delta, MAX_NS_PER_STEP);
200
201	counth = (count_val & 0xffff0000) >> 16;
202	countl = count_val & 0xffff;
203
204	negative = (negative << 15) & 0x8000;
205
206	mutex_lock(&hellcreek->ptp_lock);
207
208	/* Set offset write register */
209	hellcreek_ptp_write(hellcreek, negative, PR_CLOCK_OFFSET_C);
210	hellcreek_ptp_write(hellcreek, MAX_NS_PER_STEP, PR_CLOCK_OFFSET_C);
211	hellcreek_ptp_write(hellcreek, MIN_CLK_CYCLES_BETWEEN_STEPS,
212			    PR_CLOCK_OFFSET_C);
213	hellcreek_ptp_write(hellcreek, countl,  PR_CLOCK_OFFSET_C);
214	hellcreek_ptp_write(hellcreek, counth,  PR_CLOCK_OFFSET_C);
215
216	mutex_unlock(&hellcreek->ptp_lock);
217
218	return 0;
219}
220
221static int hellcreek_ptp_enable(struct ptp_clock_info *ptp,
222				struct ptp_clock_request *rq, int on)
223{
224	return -EOPNOTSUPP;
225}
226
227static void hellcreek_ptp_overflow_check(struct work_struct *work)
228{
229	struct delayed_work *dw = to_delayed_work(work);
230	struct hellcreek *hellcreek;
231
232	hellcreek = dw_overflow_to_hellcreek(dw);
233
234	mutex_lock(&hellcreek->ptp_lock);
235	__hellcreek_ptp_gettime(hellcreek);
236	mutex_unlock(&hellcreek->ptp_lock);
237
238	schedule_delayed_work(&hellcreek->overflow_work,
239			      HELLCREEK_OVERFLOW_PERIOD);
240}
241
242static enum led_brightness hellcreek_get_brightness(struct hellcreek *hellcreek,
243						    int led)
244{
245	return (hellcreek->status_out & led) ? 1 : 0;
246}
247
248static void hellcreek_set_brightness(struct hellcreek *hellcreek, int led,
249				     enum led_brightness b)
250{
251	mutex_lock(&hellcreek->ptp_lock);
252
253	if (b)
254		hellcreek->status_out |= led;
255	else
256		hellcreek->status_out &= ~led;
257
258	hellcreek_ptp_write(hellcreek, hellcreek->status_out, STATUS_OUT);
259
260	mutex_unlock(&hellcreek->ptp_lock);
261}
262
263static void hellcreek_led_sync_good_set(struct led_classdev *ldev,
264					enum led_brightness b)
265{
266	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
267
268	hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, b);
269}
270
271static enum led_brightness hellcreek_led_sync_good_get(struct led_classdev *ldev)
272{
273	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_sync_good);
274
275	return hellcreek_get_brightness(hellcreek, STATUS_OUT_SYNC_GOOD);
276}
277
278static void hellcreek_led_is_gm_set(struct led_classdev *ldev,
279				    enum led_brightness b)
280{
281	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
282
283	hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, b);
284}
285
286static enum led_brightness hellcreek_led_is_gm_get(struct led_classdev *ldev)
287{
288	struct hellcreek *hellcreek = led_to_hellcreek(ldev, led_is_gm);
289
290	return hellcreek_get_brightness(hellcreek, STATUS_OUT_IS_GM);
291}
292
293/* There two available LEDs internally called sync_good and is_gm. However, the
294 * user might want to use a different label and specify the default state. Take
295 * those properties from device tree.
296 */
297static int hellcreek_led_setup(struct hellcreek *hellcreek)
298{
299	struct device_node *leds, *led = NULL;
300	const char *label, *state;
 
301	int ret = -EINVAL;
302
 
303	leds = of_find_node_by_name(hellcreek->dev->of_node, "leds");
304	if (!leds) {
305		dev_err(hellcreek->dev, "No LEDs specified in device tree!\n");
306		return ret;
307	}
308
309	hellcreek->status_out = 0;
310
311	led = of_get_next_available_child(leds, led);
312	if (!led) {
313		dev_err(hellcreek->dev, "First LED not specified!\n");
314		goto out;
315	}
316
317	ret = of_property_read_string(led, "label", &label);
318	hellcreek->led_sync_good.name = ret ? "sync_good" : label;
319
320	ret = of_property_read_string(led, "default-state", &state);
321	if (!ret) {
322		if (!strcmp(state, "on"))
323			hellcreek->led_sync_good.brightness = 1;
324		else if (!strcmp(state, "off"))
325			hellcreek->led_sync_good.brightness = 0;
326		else if (!strcmp(state, "keep"))
327			hellcreek->led_sync_good.brightness =
328				hellcreek_get_brightness(hellcreek,
329							 STATUS_OUT_SYNC_GOOD);
 
330	}
331
332	hellcreek->led_sync_good.max_brightness = 1;
333	hellcreek->led_sync_good.brightness_set = hellcreek_led_sync_good_set;
334	hellcreek->led_sync_good.brightness_get = hellcreek_led_sync_good_get;
335
336	led = of_get_next_available_child(leds, led);
337	if (!led) {
338		dev_err(hellcreek->dev, "Second LED not specified!\n");
339		ret = -EINVAL;
340		goto out;
341	}
342
343	ret = of_property_read_string(led, "label", &label);
344	hellcreek->led_is_gm.name = ret ? "is_gm" : label;
345
346	ret = of_property_read_string(led, "default-state", &state);
347	if (!ret) {
348		if (!strcmp(state, "on"))
349			hellcreek->led_is_gm.brightness = 1;
350		else if (!strcmp(state, "off"))
351			hellcreek->led_is_gm.brightness = 0;
352		else if (!strcmp(state, "keep"))
353			hellcreek->led_is_gm.brightness =
354				hellcreek_get_brightness(hellcreek,
355							 STATUS_OUT_IS_GM);
 
356	}
357
358	hellcreek->led_is_gm.max_brightness = 1;
359	hellcreek->led_is_gm.brightness_set = hellcreek_led_is_gm_set;
360	hellcreek->led_is_gm.brightness_get = hellcreek_led_is_gm_get;
361
362	/* Set initial state */
363	if (hellcreek->led_sync_good.brightness == 1)
364		hellcreek_set_brightness(hellcreek, STATUS_OUT_SYNC_GOOD, 1);
365	if (hellcreek->led_is_gm.brightness == 1)
366		hellcreek_set_brightness(hellcreek, STATUS_OUT_IS_GM, 1);
367
368	/* Register both leds */
369	led_classdev_register(hellcreek->dev, &hellcreek->led_sync_good);
370	led_classdev_register(hellcreek->dev, &hellcreek->led_is_gm);
371
372	ret = 0;
373
374out:
375	of_node_put(leds);
376
377	return ret;
378}
379
380int hellcreek_ptp_setup(struct hellcreek *hellcreek)
381{
382	u16 status;
383	int ret;
384
385	/* Set up the overflow work */
386	INIT_DELAYED_WORK(&hellcreek->overflow_work,
387			  hellcreek_ptp_overflow_check);
388
389	/* Setup PTP clock */
390	hellcreek->ptp_clock_info.owner = THIS_MODULE;
391	snprintf(hellcreek->ptp_clock_info.name,
392		 sizeof(hellcreek->ptp_clock_info.name),
393		 dev_name(hellcreek->dev));
394
395	/* IP-Core can add up to 0.5 ns per 8 ns cycle, which means
396	 * accumulator_overflow_rate shall not exceed 62.5 MHz (which adjusts
397	 * the nominal frequency by 6.25%)
398	 */
399	hellcreek->ptp_clock_info.max_adj     = 62500000;
400	hellcreek->ptp_clock_info.n_alarm     = 0;
401	hellcreek->ptp_clock_info.n_pins      = 0;
402	hellcreek->ptp_clock_info.n_ext_ts    = 0;
403	hellcreek->ptp_clock_info.n_per_out   = 0;
404	hellcreek->ptp_clock_info.pps	      = 0;
405	hellcreek->ptp_clock_info.adjfine     = hellcreek_ptp_adjfine;
406	hellcreek->ptp_clock_info.adjtime     = hellcreek_ptp_adjtime;
407	hellcreek->ptp_clock_info.gettime64   = hellcreek_ptp_gettime;
408	hellcreek->ptp_clock_info.settime64   = hellcreek_ptp_settime;
409	hellcreek->ptp_clock_info.enable      = hellcreek_ptp_enable;
410	hellcreek->ptp_clock_info.do_aux_work = hellcreek_hwtstamp_work;
411
412	hellcreek->ptp_clock = ptp_clock_register(&hellcreek->ptp_clock_info,
413						  hellcreek->dev);
414	if (IS_ERR(hellcreek->ptp_clock))
415		return PTR_ERR(hellcreek->ptp_clock);
416
417	/* Enable the offset correction process, if no offset correction is
418	 * already taking place
419	 */
420	status = hellcreek_ptp_read(hellcreek, PR_CLOCK_STATUS_C);
421	if (!(status & PR_CLOCK_STATUS_C_OFS_ACT))
422		hellcreek_ptp_write(hellcreek,
423				    status | PR_CLOCK_STATUS_C_ENA_OFS,
424				    PR_CLOCK_STATUS_C);
425
426	/* Enable the drift correction process */
427	hellcreek_ptp_write(hellcreek, status | PR_CLOCK_STATUS_C_ENA_DRIFT,
428			    PR_CLOCK_STATUS_C);
429
430	/* LED setup */
431	ret = hellcreek_led_setup(hellcreek);
432	if (ret) {
433		if (hellcreek->ptp_clock)
434			ptp_clock_unregister(hellcreek->ptp_clock);
435		return ret;
436	}
437
438	schedule_delayed_work(&hellcreek->overflow_work,
439			      HELLCREEK_OVERFLOW_PERIOD);
440
441	return 0;
442}
443
444void hellcreek_ptp_free(struct hellcreek *hellcreek)
445{
446	led_classdev_unregister(&hellcreek->led_is_gm);
447	led_classdev_unregister(&hellcreek->led_sync_good);
448	cancel_delayed_work_sync(&hellcreek->overflow_work);
449	if (hellcreek->ptp_clock)
450		ptp_clock_unregister(hellcreek->ptp_clock);
451	hellcreek->ptp_clock = NULL;
452}