xref: /linux/drivers/net/ethernet/ti/icssg/icss_iep.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /* Texas Instruments ICSSG Industrial Ethernet Peripheral (IEP) Driver
4  *
5  * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com
6  *
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/err.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_platform.h>
16 #include <linux/platform_device.h>
17 #include <linux/timekeeping.h>
18 #include <linux/interrupt.h>
19 #include <linux/of_irq.h>
20 #include <linux/workqueue.h>
21 
22 #include "icss_iep.h"
23 
24 #define IEP_MAX_DEF_INC		0xf
25 #define IEP_MAX_COMPEN_INC		0xfff
26 #define IEP_MAX_COMPEN_COUNT	0xffffff
27 
28 #define IEP_GLOBAL_CFG_CNT_ENABLE	BIT(0)
29 #define IEP_GLOBAL_CFG_DEFAULT_INC_MASK		GENMASK(7, 4)
30 #define IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT	4
31 #define IEP_GLOBAL_CFG_COMPEN_INC_MASK		GENMASK(19, 8)
32 #define IEP_GLOBAL_CFG_COMPEN_INC_SHIFT		8
33 
34 #define IEP_GLOBAL_STATUS_CNT_OVF	BIT(0)
35 
36 #define IEP_CMP_CFG_SHADOW_EN		BIT(17)
37 #define IEP_CMP_CFG_CMP0_RST_CNT_EN	BIT(0)
38 #define IEP_CMP_CFG_CMP_EN(cmp)		(GENMASK(16, 1) & (1 << ((cmp) + 1)))
39 
40 #define IEP_CMP_STATUS(cmp)		(1 << (cmp))
41 
42 #define IEP_SYNC_CTRL_SYNC_EN		BIT(0)
43 #define IEP_SYNC_CTRL_SYNC_N_EN(n)	(GENMASK(2, 1) & (BIT(1) << (n)))
44 
45 #define IEP_MIN_CMP	0
46 #define IEP_MAX_CMP	15
47 
48 #define ICSS_IEP_64BIT_COUNTER_SUPPORT		BIT(0)
49 #define ICSS_IEP_SLOW_COMPEN_REG_SUPPORT	BIT(1)
50 #define ICSS_IEP_SHADOW_MODE_SUPPORT		BIT(2)
51 
52 #define LATCH_INDEX(ts_index)			((ts_index) + 6)
53 #define IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(n)	BIT(LATCH_INDEX(n))
54 #define IEP_CAP_CFG_CAP_ASYNC_EN(n)		BIT(LATCH_INDEX(n) + 10)
55 
56 /**
57  * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
58  * @iep: Pointer to structure representing IEP.
59  *
60  * Return: upper 32 bit IEP counter
61  */
62 int icss_iep_get_count_hi(struct icss_iep *iep)
63 {
64 	u32 val = 0;
65 
66 	if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
67 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
68 
69 	return val;
70 }
71 EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
72 
73 /**
74  * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
75  * @iep: Pointer to structure representing IEP.
76  *
77  * Return: lower 32 bit IEP counter
78  */
79 int icss_iep_get_count_low(struct icss_iep *iep)
80 {
81 	u32 val = 0;
82 
83 	if (iep)
84 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
85 
86 	return val;
87 }
88 EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
89 
90 /**
91  * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
92  * @iep: Pointer to structure representing IEP.
93  *
94  * Return: PTP clock index, -1 if not registered
95  */
96 int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
97 {
98 	if (!iep || !iep->ptp_clock)
99 		return -1;
100 	return ptp_clock_index(iep->ptp_clock);
101 }
102 EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
103 
104 static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
105 {
106 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
107 		writel(upper_32_bits(ns), iep->base +
108 		       iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
109 	writel(lower_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
110 }
111 
112 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
113 
114 /**
115  * icss_iep_settime() - Set time of the PTP clock using IEP driver
116  * @iep: Pointer to structure representing IEP.
117  * @ns: Time to be set in nanoseconds
118  *
119  * This API uses writel() instead of regmap_write() for write operations as
120  * regmap_write() is too slow and this API is time sensitive.
121  */
122 static void icss_iep_settime(struct icss_iep *iep, u64 ns)
123 {
124 	if (iep->ops && iep->ops->settime) {
125 		iep->ops->settime(iep->clockops_data, ns);
126 		return;
127 	}
128 
129 	if (iep->pps_enabled || iep->perout_enabled)
130 		writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
131 
132 	icss_iep_set_counter(iep, ns);
133 
134 	if (iep->pps_enabled || iep->perout_enabled) {
135 		icss_iep_update_to_next_boundary(iep, ns);
136 		writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
137 		       iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
138 	}
139 }
140 
141 /**
142  * icss_iep_gettime() - Get time of the PTP clock using IEP driver
143  * @iep: Pointer to structure representing IEP.
144  * @sts: Pointer to structure representing PTP system timestamp.
145  *
146  * This API uses readl() instead of regmap_read() for read operations as
147  * regmap_read() is too slow and this API is time sensitive.
148  *
149  * Return: The current timestamp of the PTP clock using IEP driver
150  */
151 static u64 icss_iep_gettime(struct icss_iep *iep,
152 			    struct ptp_system_timestamp *sts)
153 {
154 	u32 ts_hi = 0, ts_lo;
155 	unsigned long flags;
156 
157 	if (iep->ops && iep->ops->gettime)
158 		return iep->ops->gettime(iep->clockops_data, sts);
159 
160 	/* use local_irq_x() to make it work for both RT/non-RT */
161 	local_irq_save(flags);
162 
163 	/* no need to play with hi-lo, hi is latched when lo is read */
164 	ptp_read_system_prets(sts);
165 	ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
166 	ptp_read_system_postts(sts);
167 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
168 		ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
169 
170 	local_irq_restore(flags);
171 
172 	return (u64)ts_lo | (u64)ts_hi << 32;
173 }
174 
175 static void icss_iep_enable(struct icss_iep *iep)
176 {
177 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
178 			   IEP_GLOBAL_CFG_CNT_ENABLE,
179 			   IEP_GLOBAL_CFG_CNT_ENABLE);
180 }
181 
182 static void icss_iep_disable(struct icss_iep *iep)
183 {
184 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
185 			   IEP_GLOBAL_CFG_CNT_ENABLE,
186 			   0);
187 }
188 
189 static void icss_iep_enable_shadow_mode(struct icss_iep *iep)
190 {
191 	u32 cycle_time;
192 	int cmp;
193 
194 	cycle_time = iep->cycle_time_ns - iep->def_inc;
195 
196 	icss_iep_disable(iep);
197 
198 	/* disable shadow mode */
199 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
200 			   IEP_CMP_CFG_SHADOW_EN, 0);
201 
202 	/* enable shadow mode */
203 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
204 			   IEP_CMP_CFG_SHADOW_EN, IEP_CMP_CFG_SHADOW_EN);
205 
206 	/* clear counters */
207 	icss_iep_set_counter(iep, 0);
208 
209 	/* clear overflow status */
210 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_STATUS_REG,
211 			   IEP_GLOBAL_STATUS_CNT_OVF,
212 			   IEP_GLOBAL_STATUS_CNT_OVF);
213 
214 	/* clear compare status */
215 	for (cmp = IEP_MIN_CMP; cmp < IEP_MAX_CMP; cmp++) {
216 		regmap_update_bits(iep->map, ICSS_IEP_CMP_STAT_REG,
217 				   IEP_CMP_STATUS(cmp), IEP_CMP_STATUS(cmp));
218 	}
219 
220 	/* enable reset counter on CMP0 event */
221 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
222 			   IEP_CMP_CFG_CMP0_RST_CNT_EN,
223 			   IEP_CMP_CFG_CMP0_RST_CNT_EN);
224 	/* enable compare */
225 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
226 			   IEP_CMP_CFG_CMP_EN(0),
227 			   IEP_CMP_CFG_CMP_EN(0));
228 
229 	/* set CMP0 value to cycle time */
230 	regmap_write(iep->map, ICSS_IEP_CMP0_REG0, cycle_time);
231 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
232 		regmap_write(iep->map, ICSS_IEP_CMP0_REG1, cycle_time);
233 
234 	icss_iep_set_counter(iep, 0);
235 	icss_iep_enable(iep);
236 }
237 
238 static void icss_iep_set_default_inc(struct icss_iep *iep, u8 def_inc)
239 {
240 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
241 			   IEP_GLOBAL_CFG_DEFAULT_INC_MASK,
242 			   def_inc << IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT);
243 }
244 
245 static void icss_iep_set_compensation_inc(struct icss_iep *iep, u16 compen_inc)
246 {
247 	struct device *dev = regmap_get_device(iep->map);
248 
249 	if (compen_inc > IEP_MAX_COMPEN_INC) {
250 		dev_err(dev, "%s: too high compensation inc %d\n",
251 			__func__, compen_inc);
252 		compen_inc = IEP_MAX_COMPEN_INC;
253 	}
254 
255 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
256 			   IEP_GLOBAL_CFG_COMPEN_INC_MASK,
257 			   compen_inc << IEP_GLOBAL_CFG_COMPEN_INC_SHIFT);
258 }
259 
260 static void icss_iep_set_compensation_count(struct icss_iep *iep,
261 					    u32 compen_count)
262 {
263 	struct device *dev = regmap_get_device(iep->map);
264 
265 	if (compen_count > IEP_MAX_COMPEN_COUNT) {
266 		dev_err(dev, "%s: too high compensation count %d\n",
267 			__func__, compen_count);
268 		compen_count = IEP_MAX_COMPEN_COUNT;
269 	}
270 
271 	regmap_write(iep->map, ICSS_IEP_COMPEN_REG, compen_count);
272 }
273 
274 static void icss_iep_set_slow_compensation_count(struct icss_iep *iep,
275 						 u32 compen_count)
276 {
277 	regmap_write(iep->map, ICSS_IEP_SLOW_COMPEN_REG, compen_count);
278 }
279 
280 /* PTP PHC operations */
281 static int icss_iep_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
282 {
283 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
284 	s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
285 	u32 cyc_count;
286 	u16 cmp_inc;
287 
288 	mutex_lock(&iep->ptp_clk_mutex);
289 
290 	/* ppb is amount of frequency we want to adjust in 1GHz (billion)
291 	 * e.g. 100ppb means we need to speed up clock by 100Hz
292 	 * i.e. at end of 1 second (1 billion ns) clock time, we should be
293 	 * counting 100 more ns.
294 	 * We use IEP slow compensation to achieve continuous freq. adjustment.
295 	 * There are 2 parts. Cycle time and adjustment per cycle.
296 	 * Simplest case would be 1 sec Cycle time. Then adjustment
297 	 * pre cycle would be (def_inc + ppb) value.
298 	 * Cycle time will have to be chosen based on how worse the ppb is.
299 	 * e.g. smaller the ppb, cycle time has to be large.
300 	 * The minimum adjustment we can do is +-1ns per cycle so let's
301 	 * reduce the cycle time to get 1ns per cycle adjustment.
302 	 *	1ppb = 1sec cycle time & 1ns adjust
303 	 *	1000ppb = 1/1000 cycle time & 1ns adjust per cycle
304 	 */
305 
306 	if (iep->cycle_time_ns)
307 		iep->slow_cmp_inc = iep->clk_tick_time;	/* 4ns adj per cycle */
308 	else
309 		iep->slow_cmp_inc = 1;	/* 1ns adjust per cycle */
310 
311 	if (ppb < 0) {
312 		iep->slow_cmp_inc = -iep->slow_cmp_inc;
313 		ppb = -ppb;
314 	}
315 
316 	cyc_count = NSEC_PER_SEC;		/* 1s cycle time @1GHz */
317 	cyc_count /= ppb;		/* cycle time per ppb */
318 
319 	/* slow_cmp_count is decremented every clock cycle, e.g. @250MHz */
320 	if (!iep->cycle_time_ns)
321 		cyc_count /= iep->clk_tick_time;
322 	iep->slow_cmp_count = cyc_count;
323 
324 	/* iep->clk_tick_time is def_inc */
325 	cmp_inc = iep->clk_tick_time + iep->slow_cmp_inc;
326 	icss_iep_set_compensation_inc(iep, cmp_inc);
327 	icss_iep_set_slow_compensation_count(iep, iep->slow_cmp_count);
328 
329 	mutex_unlock(&iep->ptp_clk_mutex);
330 
331 	return 0;
332 }
333 
334 static int icss_iep_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
335 {
336 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
337 	s64 ns;
338 
339 	mutex_lock(&iep->ptp_clk_mutex);
340 	if (iep->ops && iep->ops->adjtime) {
341 		iep->ops->adjtime(iep->clockops_data, delta);
342 	} else {
343 		ns = icss_iep_gettime(iep, NULL);
344 		ns += delta;
345 		icss_iep_settime(iep, ns);
346 	}
347 	mutex_unlock(&iep->ptp_clk_mutex);
348 
349 	return 0;
350 }
351 
352 static int icss_iep_ptp_gettimeex(struct ptp_clock_info *ptp,
353 				  struct timespec64 *ts,
354 				  struct ptp_system_timestamp *sts)
355 {
356 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
357 	u64 ns;
358 
359 	mutex_lock(&iep->ptp_clk_mutex);
360 	ns = icss_iep_gettime(iep, sts);
361 	*ts = ns_to_timespec64(ns);
362 	mutex_unlock(&iep->ptp_clk_mutex);
363 
364 	return 0;
365 }
366 
367 static int icss_iep_ptp_settime(struct ptp_clock_info *ptp,
368 				const struct timespec64 *ts)
369 {
370 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
371 	u64 ns;
372 
373 	mutex_lock(&iep->ptp_clk_mutex);
374 	ns = timespec64_to_ns(ts);
375 	icss_iep_settime(iep, ns);
376 	mutex_unlock(&iep->ptp_clk_mutex);
377 
378 	return 0;
379 }
380 
381 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
382 {
383 	u64 ns, p_ns;
384 	u32 offset;
385 
386 	ns = icss_iep_gettime(iep, NULL);
387 	if (start_ns < ns)
388 		start_ns = ns;
389 	p_ns = iep->period;
390 	/* Round up to next period boundary */
391 	start_ns += p_ns - 1;
392 	offset = do_div(start_ns, p_ns);
393 	start_ns = start_ns * p_ns;
394 	/* If it is too close to update, shift to next boundary */
395 	if (p_ns - offset < 10)
396 		start_ns += p_ns;
397 
398 	regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(start_ns));
399 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
400 		regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(start_ns));
401 }
402 
403 static int icss_iep_perout_enable_hw(struct icss_iep *iep,
404 				     struct ptp_perout_request *req, int on)
405 {
406 	int ret;
407 	u64 cmp;
408 
409 	if (iep->ops && iep->ops->perout_enable) {
410 		ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
411 		if (ret)
412 			return ret;
413 
414 		if (on) {
415 			/* Configure CMP */
416 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
417 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
418 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
419 			/* Configure SYNC, 1ms pulse width */
420 			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, 1000000);
421 			regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
422 			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
423 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
424 			/* Enable CMP 1 */
425 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
426 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
427 		} else {
428 			/* Disable CMP 1 */
429 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
430 					   IEP_CMP_CFG_CMP_EN(1), 0);
431 
432 			/* clear regs */
433 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
434 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
435 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
436 		}
437 	} else {
438 		if (on) {
439 			u64 start_ns;
440 
441 			iep->period = ((u64)req->period.sec * NSEC_PER_SEC) +
442 				      req->period.nsec;
443 			start_ns = ((u64)req->period.sec * NSEC_PER_SEC)
444 				   + req->period.nsec;
445 			icss_iep_update_to_next_boundary(iep, start_ns);
446 
447 			/* Enable Sync in single shot mode  */
448 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
449 				     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
450 			/* Enable CMP 1 */
451 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
452 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
453 		} else {
454 			/* Disable CMP 1 */
455 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
456 					   IEP_CMP_CFG_CMP_EN(1), 0);
457 
458 			/* clear CMP regs */
459 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
460 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
461 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
462 
463 			/* Disable sync */
464 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0);
465 		}
466 	}
467 
468 	return 0;
469 }
470 
471 static int icss_iep_perout_enable(struct icss_iep *iep,
472 				  struct ptp_perout_request *req, int on)
473 {
474 	int ret = 0;
475 
476 	mutex_lock(&iep->ptp_clk_mutex);
477 
478 	if (iep->pps_enabled) {
479 		ret = -EBUSY;
480 		goto exit;
481 	}
482 
483 	if (iep->perout_enabled == !!on)
484 		goto exit;
485 
486 	ret = icss_iep_perout_enable_hw(iep, req, on);
487 	if (!ret)
488 		iep->perout_enabled = !!on;
489 
490 exit:
491 	mutex_unlock(&iep->ptp_clk_mutex);
492 
493 	return ret;
494 }
495 
496 static void icss_iep_cap_cmp_work(struct work_struct *work)
497 {
498 	struct icss_iep *iep = container_of(work, struct icss_iep, work);
499 	const u32 *reg_offs = iep->plat_data->reg_offs;
500 	struct ptp_clock_event pevent;
501 	unsigned int val;
502 	u64 ns, ns_next;
503 
504 	mutex_lock(&iep->ptp_clk_mutex);
505 
506 	ns = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
507 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) {
508 		val = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
509 		ns |= (u64)val << 32;
510 	}
511 	/* set next event */
512 	ns_next = ns + iep->period;
513 	writel(lower_32_bits(ns_next),
514 	       iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
515 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
516 		writel(upper_32_bits(ns_next),
517 		       iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
518 
519 	pevent.pps_times.ts_real = ns_to_timespec64(ns);
520 	pevent.type = PTP_CLOCK_PPSUSR;
521 	pevent.index = 0;
522 	ptp_clock_event(iep->ptp_clock, &pevent);
523 	dev_dbg(iep->dev, "IEP:pps ts: %llu next:%llu:\n", ns, ns_next);
524 
525 	mutex_unlock(&iep->ptp_clk_mutex);
526 }
527 
528 static irqreturn_t icss_iep_cap_cmp_irq(int irq, void *dev_id)
529 {
530 	struct icss_iep *iep = (struct icss_iep *)dev_id;
531 	const u32 *reg_offs = iep->plat_data->reg_offs;
532 	unsigned int val;
533 
534 	val = readl(iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
535 	/* The driver only enables CMP1 */
536 	if (val & BIT(1)) {
537 		/* Clear the event */
538 		writel(BIT(1), iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
539 		if (iep->pps_enabled || iep->perout_enabled)
540 			schedule_work(&iep->work);
541 		return IRQ_HANDLED;
542 	}
543 
544 	return IRQ_NONE;
545 }
546 
547 static int icss_iep_pps_enable(struct icss_iep *iep, int on)
548 {
549 	struct ptp_clock_request rq;
550 	struct timespec64 ts;
551 	int ret = 0;
552 	u64 ns;
553 
554 	mutex_lock(&iep->ptp_clk_mutex);
555 
556 	if (iep->perout_enabled) {
557 		ret = -EBUSY;
558 		goto exit;
559 	}
560 
561 	if (iep->pps_enabled == !!on)
562 		goto exit;
563 
564 	rq.perout.index = 0;
565 	if (on) {
566 		ns = icss_iep_gettime(iep, NULL);
567 		ts = ns_to_timespec64(ns);
568 		rq.perout.period.sec = 1;
569 		rq.perout.period.nsec = 0;
570 		rq.perout.start.sec = ts.tv_sec + 2;
571 		rq.perout.start.nsec = 0;
572 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
573 	} else {
574 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
575 		if (iep->cap_cmp_irq)
576 			cancel_work_sync(&iep->work);
577 	}
578 
579 	if (!ret)
580 		iep->pps_enabled = !!on;
581 
582 exit:
583 	mutex_unlock(&iep->ptp_clk_mutex);
584 
585 	return ret;
586 }
587 
588 static int icss_iep_extts_enable(struct icss_iep *iep, u32 index, int on)
589 {
590 	u32 val, cap, ret = 0;
591 
592 	mutex_lock(&iep->ptp_clk_mutex);
593 
594 	if (iep->ops && iep->ops->extts_enable) {
595 		ret = iep->ops->extts_enable(iep->clockops_data, index, on);
596 		goto exit;
597 	}
598 
599 	if (((iep->latch_enable & BIT(index)) >> index) == on)
600 		goto exit;
601 
602 	regmap_read(iep->map, ICSS_IEP_CAPTURE_CFG_REG, &val);
603 	cap = IEP_CAP_CFG_CAP_ASYNC_EN(index) | IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(index);
604 	if (on) {
605 		val |= cap;
606 		iep->latch_enable |= BIT(index);
607 	} else {
608 		val &= ~cap;
609 		iep->latch_enable &= ~BIT(index);
610 	}
611 	regmap_write(iep->map, ICSS_IEP_CAPTURE_CFG_REG, val);
612 
613 exit:
614 	mutex_unlock(&iep->ptp_clk_mutex);
615 
616 	return ret;
617 }
618 
619 static int icss_iep_ptp_enable(struct ptp_clock_info *ptp,
620 			       struct ptp_clock_request *rq, int on)
621 {
622 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
623 
624 	switch (rq->type) {
625 	case PTP_CLK_REQ_PEROUT:
626 		return icss_iep_perout_enable(iep, &rq->perout, on);
627 	case PTP_CLK_REQ_PPS:
628 		return icss_iep_pps_enable(iep, on);
629 	case PTP_CLK_REQ_EXTTS:
630 		return icss_iep_extts_enable(iep, rq->extts.index, on);
631 	default:
632 		break;
633 	}
634 
635 	return -EOPNOTSUPP;
636 }
637 
638 static struct ptp_clock_info icss_iep_ptp_info = {
639 	.owner		= THIS_MODULE,
640 	.name		= "ICSS IEP timer",
641 	.max_adj	= 10000000,
642 	.adjfine	= icss_iep_ptp_adjfine,
643 	.adjtime	= icss_iep_ptp_adjtime,
644 	.gettimex64	= icss_iep_ptp_gettimeex,
645 	.settime64	= icss_iep_ptp_settime,
646 	.enable		= icss_iep_ptp_enable,
647 };
648 
649 struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx)
650 {
651 	struct platform_device *pdev;
652 	struct device_node *iep_np;
653 	struct icss_iep *iep;
654 
655 	iep_np = of_parse_phandle(np, "ti,iep", idx);
656 	if (!iep_np || !of_device_is_available(iep_np))
657 		return ERR_PTR(-ENODEV);
658 
659 	pdev = of_find_device_by_node(iep_np);
660 	of_node_put(iep_np);
661 
662 	if (!pdev)
663 		/* probably IEP not yet probed */
664 		return ERR_PTR(-EPROBE_DEFER);
665 
666 	iep = platform_get_drvdata(pdev);
667 	if (!iep)
668 		return ERR_PTR(-EPROBE_DEFER);
669 
670 	device_lock(iep->dev);
671 	if (iep->client_np) {
672 		device_unlock(iep->dev);
673 		dev_err(iep->dev, "IEP is already acquired by %s",
674 			iep->client_np->name);
675 		return ERR_PTR(-EBUSY);
676 	}
677 	iep->client_np = np;
678 	device_unlock(iep->dev);
679 	get_device(iep->dev);
680 
681 	return iep;
682 }
683 EXPORT_SYMBOL_GPL(icss_iep_get_idx);
684 
685 struct icss_iep *icss_iep_get(struct device_node *np)
686 {
687 	return icss_iep_get_idx(np, 0);
688 }
689 EXPORT_SYMBOL_GPL(icss_iep_get);
690 
691 void icss_iep_put(struct icss_iep *iep)
692 {
693 	device_lock(iep->dev);
694 	iep->client_np = NULL;
695 	device_unlock(iep->dev);
696 	put_device(iep->dev);
697 }
698 EXPORT_SYMBOL_GPL(icss_iep_put);
699 
700 void icss_iep_init_fw(struct icss_iep *iep)
701 {
702 	/* start IEP for FW use in raw 64bit mode, no PTP support */
703 	iep->clk_tick_time = iep->def_inc;
704 	iep->cycle_time_ns = 0;
705 	iep->ops = NULL;
706 	iep->clockops_data = NULL;
707 	icss_iep_set_default_inc(iep, iep->def_inc);
708 	icss_iep_set_compensation_inc(iep, iep->def_inc);
709 	icss_iep_set_compensation_count(iep, 0);
710 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
711 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
712 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
713 		icss_iep_set_slow_compensation_count(iep, 0);
714 
715 	icss_iep_enable(iep);
716 	icss_iep_settime(iep, 0);
717 }
718 EXPORT_SYMBOL_GPL(icss_iep_init_fw);
719 
720 void icss_iep_exit_fw(struct icss_iep *iep)
721 {
722 	icss_iep_disable(iep);
723 }
724 EXPORT_SYMBOL_GPL(icss_iep_exit_fw);
725 
726 int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
727 		  void *clockops_data, u32 cycle_time_ns)
728 {
729 	int ret = 0;
730 
731 	iep->cycle_time_ns = cycle_time_ns;
732 	iep->clk_tick_time = iep->def_inc;
733 	iep->ops = clkops;
734 	iep->clockops_data = clockops_data;
735 	icss_iep_set_default_inc(iep, iep->def_inc);
736 	icss_iep_set_compensation_inc(iep, iep->def_inc);
737 	icss_iep_set_compensation_count(iep, 0);
738 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
739 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
740 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
741 		icss_iep_set_slow_compensation_count(iep, 0);
742 
743 	if (!(iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) ||
744 	    !(iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT))
745 		goto skip_perout;
746 
747 	if (iep->ops && iep->ops->perout_enable) {
748 		iep->ptp_info.n_per_out = 1;
749 		iep->ptp_info.pps = 1;
750 	} else if (iep->cap_cmp_irq) {
751 		iep->ptp_info.pps = 1;
752 	}
753 
754 	if (iep->ops && iep->ops->extts_enable)
755 		iep->ptp_info.n_ext_ts = 2;
756 
757 skip_perout:
758 	if (cycle_time_ns)
759 		icss_iep_enable_shadow_mode(iep);
760 	else
761 		icss_iep_enable(iep);
762 	icss_iep_settime(iep, ktime_get_real_ns());
763 
764 	iep->ptp_clock = ptp_clock_register(&iep->ptp_info, iep->dev);
765 	if (IS_ERR(iep->ptp_clock)) {
766 		ret = PTR_ERR(iep->ptp_clock);
767 		iep->ptp_clock = NULL;
768 		dev_err(iep->dev, "Failed to register ptp clk %d\n", ret);
769 	}
770 
771 	return ret;
772 }
773 EXPORT_SYMBOL_GPL(icss_iep_init);
774 
775 int icss_iep_exit(struct icss_iep *iep)
776 {
777 	if (iep->ptp_clock) {
778 		ptp_clock_unregister(iep->ptp_clock);
779 		iep->ptp_clock = NULL;
780 	}
781 	icss_iep_disable(iep);
782 
783 	return 0;
784 }
785 EXPORT_SYMBOL_GPL(icss_iep_exit);
786 
787 static int icss_iep_probe(struct platform_device *pdev)
788 {
789 	struct device *dev = &pdev->dev;
790 	struct icss_iep *iep;
791 	struct clk *iep_clk;
792 	int ret, irq;
793 
794 	iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
795 	if (!iep)
796 		return -ENOMEM;
797 
798 	iep->dev = dev;
799 	iep->base = devm_platform_ioremap_resource(pdev, 0);
800 	if (IS_ERR(iep->base))
801 		return -ENODEV;
802 
803 	irq = platform_get_irq_byname_optional(pdev, "iep_cap_cmp");
804 	if (irq == -EPROBE_DEFER)
805 		return irq;
806 
807 	if (irq > 0) {
808 		ret = devm_request_irq(dev, irq, icss_iep_cap_cmp_irq,
809 				       IRQF_TRIGGER_HIGH, "iep_cap_cmp", iep);
810 		if (ret) {
811 			dev_info(iep->dev, "cap_cmp irq request failed: %x\n",
812 				 ret);
813 		} else {
814 			iep->cap_cmp_irq = irq;
815 			INIT_WORK(&iep->work, icss_iep_cap_cmp_work);
816 		}
817 	}
818 
819 	iep_clk = devm_clk_get(dev, NULL);
820 	if (IS_ERR(iep_clk))
821 		return PTR_ERR(iep_clk);
822 
823 	iep->refclk_freq = clk_get_rate(iep_clk);
824 
825 	iep->def_inc = NSEC_PER_SEC / iep->refclk_freq;	/* ns per clock tick */
826 	if (iep->def_inc > IEP_MAX_DEF_INC) {
827 		dev_err(dev, "Failed to set def_inc %d.  IEP_clock is too slow to be supported\n",
828 			iep->def_inc);
829 		return -EINVAL;
830 	}
831 
832 	iep->plat_data = device_get_match_data(dev);
833 	if (!iep->plat_data)
834 		return -EINVAL;
835 
836 	iep->map = devm_regmap_init(dev, NULL, iep, iep->plat_data->config);
837 	if (IS_ERR(iep->map)) {
838 		dev_err(dev, "Failed to create regmap for IEP %ld\n",
839 			PTR_ERR(iep->map));
840 		return PTR_ERR(iep->map);
841 	}
842 
843 	iep->ptp_info = icss_iep_ptp_info;
844 	mutex_init(&iep->ptp_clk_mutex);
845 	dev_set_drvdata(dev, iep);
846 	icss_iep_disable(iep);
847 
848 	return 0;
849 }
850 
851 static bool am654_icss_iep_valid_reg(struct device *dev, unsigned int reg)
852 {
853 	switch (reg) {
854 	case ICSS_IEP_GLOBAL_CFG_REG ... ICSS_IEP_SYNC_START_REG:
855 		return true;
856 	default:
857 		return false;
858 	}
859 
860 	return false;
861 }
862 
863 static int icss_iep_regmap_write(void *context, unsigned int reg,
864 				 unsigned int val)
865 {
866 	struct icss_iep *iep = context;
867 
868 	writel(val, iep->base + iep->plat_data->reg_offs[reg]);
869 
870 	return 0;
871 }
872 
873 static int icss_iep_regmap_read(void *context, unsigned int reg,
874 				unsigned int *val)
875 {
876 	struct icss_iep *iep = context;
877 
878 	*val = readl(iep->base + iep->plat_data->reg_offs[reg]);
879 
880 	return 0;
881 }
882 
883 static const struct regmap_config am654_icss_iep_regmap_config = {
884 	.name = "icss iep",
885 	.reg_stride = 1,
886 	.reg_write = icss_iep_regmap_write,
887 	.reg_read = icss_iep_regmap_read,
888 	.writeable_reg = am654_icss_iep_valid_reg,
889 	.readable_reg = am654_icss_iep_valid_reg,
890 	.fast_io = 1,
891 };
892 
893 static const struct icss_iep_plat_data am654_icss_iep_plat_data = {
894 	.flags = ICSS_IEP_64BIT_COUNTER_SUPPORT |
895 		 ICSS_IEP_SLOW_COMPEN_REG_SUPPORT |
896 		 ICSS_IEP_SHADOW_MODE_SUPPORT,
897 	.reg_offs = {
898 		[ICSS_IEP_GLOBAL_CFG_REG] = 0x00,
899 		[ICSS_IEP_COMPEN_REG] = 0x08,
900 		[ICSS_IEP_SLOW_COMPEN_REG] = 0x0C,
901 		[ICSS_IEP_COUNT_REG0] = 0x10,
902 		[ICSS_IEP_COUNT_REG1] = 0x14,
903 		[ICSS_IEP_CAPTURE_CFG_REG] = 0x18,
904 		[ICSS_IEP_CAPTURE_STAT_REG] = 0x1c,
905 
906 		[ICSS_IEP_CAP6_RISE_REG0] = 0x50,
907 		[ICSS_IEP_CAP6_RISE_REG1] = 0x54,
908 
909 		[ICSS_IEP_CAP7_RISE_REG0] = 0x60,
910 		[ICSS_IEP_CAP7_RISE_REG1] = 0x64,
911 
912 		[ICSS_IEP_CMP_CFG_REG] = 0x70,
913 		[ICSS_IEP_CMP_STAT_REG] = 0x74,
914 		[ICSS_IEP_CMP0_REG0] = 0x78,
915 		[ICSS_IEP_CMP0_REG1] = 0x7c,
916 		[ICSS_IEP_CMP1_REG0] = 0x80,
917 		[ICSS_IEP_CMP1_REG1] = 0x84,
918 
919 		[ICSS_IEP_CMP8_REG0] = 0xc0,
920 		[ICSS_IEP_CMP8_REG1] = 0xc4,
921 		[ICSS_IEP_SYNC_CTRL_REG] = 0x180,
922 		[ICSS_IEP_SYNC0_STAT_REG] = 0x188,
923 		[ICSS_IEP_SYNC1_STAT_REG] = 0x18c,
924 		[ICSS_IEP_SYNC_PWIDTH_REG] = 0x190,
925 		[ICSS_IEP_SYNC0_PERIOD_REG] = 0x194,
926 		[ICSS_IEP_SYNC1_DELAY_REG] = 0x198,
927 		[ICSS_IEP_SYNC_START_REG] = 0x19c,
928 	},
929 	.config = &am654_icss_iep_regmap_config,
930 };
931 
932 static const struct of_device_id icss_iep_of_match[] = {
933 	{
934 		.compatible = "ti,am654-icss-iep",
935 		.data = &am654_icss_iep_plat_data,
936 	},
937 	{},
938 };
939 MODULE_DEVICE_TABLE(of, icss_iep_of_match);
940 
941 static struct platform_driver icss_iep_driver = {
942 	.driver = {
943 		.name = "icss-iep",
944 		.of_match_table = icss_iep_of_match,
945 	},
946 	.probe = icss_iep_probe,
947 };
948 module_platform_driver(icss_iep_driver);
949 
950 MODULE_LICENSE("GPL");
951 MODULE_DESCRIPTION("TI ICSS IEP driver");
952 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
953 MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
954