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 
21 #include "icss_iep.h"
22 
23 #define IEP_MAX_DEF_INC		0xf
24 #define IEP_MAX_COMPEN_INC		0xfff
25 #define IEP_MAX_COMPEN_COUNT	0xffffff
26 
27 #define IEP_GLOBAL_CFG_CNT_ENABLE	BIT(0)
28 #define IEP_GLOBAL_CFG_DEFAULT_INC_MASK		GENMASK(7, 4)
29 #define IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT	4
30 #define IEP_GLOBAL_CFG_COMPEN_INC_MASK		GENMASK(19, 8)
31 #define IEP_GLOBAL_CFG_COMPEN_INC_SHIFT		8
32 
33 #define IEP_GLOBAL_STATUS_CNT_OVF	BIT(0)
34 
35 #define IEP_CMP_CFG_SHADOW_EN		BIT(17)
36 #define IEP_CMP_CFG_CMP0_RST_CNT_EN	BIT(0)
37 #define IEP_CMP_CFG_CMP_EN(cmp)		(GENMASK(16, 1) & (1 << ((cmp) + 1)))
38 
39 #define IEP_CMP_STATUS(cmp)		(1 << (cmp))
40 
41 #define IEP_SYNC_CTRL_SYNC_EN		BIT(0)
42 #define IEP_SYNC_CTRL_SYNC_N_EN(n)	(GENMASK(2, 1) & (BIT(1) << (n)))
43 
44 #define IEP_MIN_CMP	0
45 #define IEP_MAX_CMP	15
46 
47 #define ICSS_IEP_64BIT_COUNTER_SUPPORT		BIT(0)
48 #define ICSS_IEP_SLOW_COMPEN_REG_SUPPORT	BIT(1)
49 #define ICSS_IEP_SHADOW_MODE_SUPPORT		BIT(2)
50 
51 #define LATCH_INDEX(ts_index)			((ts_index) + 6)
52 #define IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(n)	BIT(LATCH_INDEX(n))
53 #define IEP_CAP_CFG_CAP_ASYNC_EN(n)		BIT(LATCH_INDEX(n) + 10)
54 
55 enum {
56 	ICSS_IEP_GLOBAL_CFG_REG,
57 	ICSS_IEP_GLOBAL_STATUS_REG,
58 	ICSS_IEP_COMPEN_REG,
59 	ICSS_IEP_SLOW_COMPEN_REG,
60 	ICSS_IEP_COUNT_REG0,
61 	ICSS_IEP_COUNT_REG1,
62 	ICSS_IEP_CAPTURE_CFG_REG,
63 	ICSS_IEP_CAPTURE_STAT_REG,
64 
65 	ICSS_IEP_CAP6_RISE_REG0,
66 	ICSS_IEP_CAP6_RISE_REG1,
67 
68 	ICSS_IEP_CAP7_RISE_REG0,
69 	ICSS_IEP_CAP7_RISE_REG1,
70 
71 	ICSS_IEP_CMP_CFG_REG,
72 	ICSS_IEP_CMP_STAT_REG,
73 	ICSS_IEP_CMP0_REG0,
74 	ICSS_IEP_CMP0_REG1,
75 	ICSS_IEP_CMP1_REG0,
76 	ICSS_IEP_CMP1_REG1,
77 
78 	ICSS_IEP_CMP8_REG0,
79 	ICSS_IEP_CMP8_REG1,
80 	ICSS_IEP_SYNC_CTRL_REG,
81 	ICSS_IEP_SYNC0_STAT_REG,
82 	ICSS_IEP_SYNC1_STAT_REG,
83 	ICSS_IEP_SYNC_PWIDTH_REG,
84 	ICSS_IEP_SYNC0_PERIOD_REG,
85 	ICSS_IEP_SYNC1_DELAY_REG,
86 	ICSS_IEP_SYNC_START_REG,
87 	ICSS_IEP_MAX_REGS,
88 };
89 
90 /**
91  * struct icss_iep_plat_data - Plat data to handle SoC variants
92  * @config: Regmap configuration data
93  * @reg_offs: register offsets to capture offset differences across SoCs
94  * @flags: Flags to represent IEP properties
95  */
96 struct icss_iep_plat_data {
97 	struct regmap_config *config;
98 	u32 reg_offs[ICSS_IEP_MAX_REGS];
99 	u32 flags;
100 };
101 
102 struct icss_iep {
103 	struct device *dev;
104 	void __iomem *base;
105 	const struct icss_iep_plat_data *plat_data;
106 	struct regmap *map;
107 	struct device_node *client_np;
108 	unsigned long refclk_freq;
109 	int clk_tick_time;	/* one refclk tick time in ns */
110 	struct ptp_clock_info ptp_info;
111 	struct ptp_clock *ptp_clock;
112 	struct mutex ptp_clk_mutex;	/* PHC access serializer */
113 	spinlock_t irq_lock; /* CMP IRQ vs icss_iep_ptp_enable access */
114 	u32 def_inc;
115 	s16 slow_cmp_inc;
116 	u32 slow_cmp_count;
117 	const struct icss_iep_clockops *ops;
118 	void *clockops_data;
119 	u32 cycle_time_ns;
120 	u32 perout_enabled;
121 	bool pps_enabled;
122 	int cap_cmp_irq;
123 	u64 period;
124 	u32 latch_enable;
125 };
126 
127 /**
128  * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
129  * @iep: Pointer to structure representing IEP.
130  *
131  * Return: upper 32 bit IEP counter
132  */
133 int icss_iep_get_count_hi(struct icss_iep *iep)
134 {
135 	u32 val = 0;
136 
137 	if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
138 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
139 
140 	return val;
141 }
142 EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
143 
144 /**
145  * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
146  * @iep: Pointer to structure representing IEP.
147  *
148  * Return: lower 32 bit IEP counter
149  */
150 int icss_iep_get_count_low(struct icss_iep *iep)
151 {
152 	u32 val = 0;
153 
154 	if (iep)
155 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
156 
157 	return val;
158 }
159 EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
160 
161 /**
162  * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
163  * @iep: Pointer to structure representing IEP.
164  *
165  * Return: PTP clock index, -1 if not registered
166  */
167 int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
168 {
169 	if (!iep || !iep->ptp_clock)
170 		return -1;
171 	return ptp_clock_index(iep->ptp_clock);
172 }
173 EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
174 
175 static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
176 {
177 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
178 		writel(upper_32_bits(ns), iep->base +
179 		       iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
180 	writel(lower_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
181 }
182 
183 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
184 
185 /**
186  * icss_iep_settime() - Set time of the PTP clock using IEP driver
187  * @iep: Pointer to structure representing IEP.
188  * @ns: Time to be set in nanoseconds
189  *
190  * This API uses writel() instead of regmap_write() for write operations as
191  * regmap_write() is too slow and this API is time sensitive.
192  */
193 static void icss_iep_settime(struct icss_iep *iep, u64 ns)
194 {
195 	unsigned long flags;
196 
197 	if (iep->ops && iep->ops->settime) {
198 		iep->ops->settime(iep->clockops_data, ns);
199 		return;
200 	}
201 
202 	spin_lock_irqsave(&iep->irq_lock, flags);
203 	if (iep->pps_enabled || iep->perout_enabled)
204 		writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
205 
206 	icss_iep_set_counter(iep, ns);
207 
208 	if (iep->pps_enabled || iep->perout_enabled) {
209 		icss_iep_update_to_next_boundary(iep, ns);
210 		writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
211 		       iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
212 	}
213 	spin_unlock_irqrestore(&iep->irq_lock, flags);
214 }
215 
216 /**
217  * icss_iep_gettime() - Get time of the PTP clock using IEP driver
218  * @iep: Pointer to structure representing IEP.
219  * @sts: Pointer to structure representing PTP system timestamp.
220  *
221  * This API uses readl() instead of regmap_read() for read operations as
222  * regmap_read() is too slow and this API is time sensitive.
223  *
224  * Return: The current timestamp of the PTP clock using IEP driver
225  */
226 static u64 icss_iep_gettime(struct icss_iep *iep,
227 			    struct ptp_system_timestamp *sts)
228 {
229 	u32 ts_hi = 0, ts_lo;
230 	unsigned long flags;
231 
232 	if (iep->ops && iep->ops->gettime)
233 		return iep->ops->gettime(iep->clockops_data, sts);
234 
235 	/* use local_irq_x() to make it work for both RT/non-RT */
236 	local_irq_save(flags);
237 
238 	/* no need to play with hi-lo, hi is latched when lo is read */
239 	ptp_read_system_prets(sts);
240 	ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
241 	ptp_read_system_postts(sts);
242 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
243 		ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
244 
245 	local_irq_restore(flags);
246 
247 	return (u64)ts_lo | (u64)ts_hi << 32;
248 }
249 
250 static void icss_iep_enable(struct icss_iep *iep)
251 {
252 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
253 			   IEP_GLOBAL_CFG_CNT_ENABLE,
254 			   IEP_GLOBAL_CFG_CNT_ENABLE);
255 }
256 
257 static void icss_iep_disable(struct icss_iep *iep)
258 {
259 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
260 			   IEP_GLOBAL_CFG_CNT_ENABLE,
261 			   0);
262 }
263 
264 static void icss_iep_enable_shadow_mode(struct icss_iep *iep)
265 {
266 	u32 cycle_time;
267 	int cmp;
268 
269 	cycle_time = iep->cycle_time_ns - iep->def_inc;
270 
271 	icss_iep_disable(iep);
272 
273 	/* disable shadow mode */
274 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
275 			   IEP_CMP_CFG_SHADOW_EN, 0);
276 
277 	/* enable shadow mode */
278 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
279 			   IEP_CMP_CFG_SHADOW_EN, IEP_CMP_CFG_SHADOW_EN);
280 
281 	/* clear counters */
282 	icss_iep_set_counter(iep, 0);
283 
284 	/* clear overflow status */
285 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_STATUS_REG,
286 			   IEP_GLOBAL_STATUS_CNT_OVF,
287 			   IEP_GLOBAL_STATUS_CNT_OVF);
288 
289 	/* clear compare status */
290 	for (cmp = IEP_MIN_CMP; cmp < IEP_MAX_CMP; cmp++) {
291 		regmap_update_bits(iep->map, ICSS_IEP_CMP_STAT_REG,
292 				   IEP_CMP_STATUS(cmp), IEP_CMP_STATUS(cmp));
293 	}
294 
295 	/* enable reset counter on CMP0 event */
296 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
297 			   IEP_CMP_CFG_CMP0_RST_CNT_EN,
298 			   IEP_CMP_CFG_CMP0_RST_CNT_EN);
299 	/* enable compare */
300 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
301 			   IEP_CMP_CFG_CMP_EN(0),
302 			   IEP_CMP_CFG_CMP_EN(0));
303 
304 	/* set CMP0 value to cycle time */
305 	regmap_write(iep->map, ICSS_IEP_CMP0_REG0, cycle_time);
306 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
307 		regmap_write(iep->map, ICSS_IEP_CMP0_REG1, cycle_time);
308 
309 	icss_iep_set_counter(iep, 0);
310 	icss_iep_enable(iep);
311 }
312 
313 static void icss_iep_set_default_inc(struct icss_iep *iep, u8 def_inc)
314 {
315 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
316 			   IEP_GLOBAL_CFG_DEFAULT_INC_MASK,
317 			   def_inc << IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT);
318 }
319 
320 static void icss_iep_set_compensation_inc(struct icss_iep *iep, u16 compen_inc)
321 {
322 	struct device *dev = regmap_get_device(iep->map);
323 
324 	if (compen_inc > IEP_MAX_COMPEN_INC) {
325 		dev_err(dev, "%s: too high compensation inc %d\n",
326 			__func__, compen_inc);
327 		compen_inc = IEP_MAX_COMPEN_INC;
328 	}
329 
330 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
331 			   IEP_GLOBAL_CFG_COMPEN_INC_MASK,
332 			   compen_inc << IEP_GLOBAL_CFG_COMPEN_INC_SHIFT);
333 }
334 
335 static void icss_iep_set_compensation_count(struct icss_iep *iep,
336 					    u32 compen_count)
337 {
338 	struct device *dev = regmap_get_device(iep->map);
339 
340 	if (compen_count > IEP_MAX_COMPEN_COUNT) {
341 		dev_err(dev, "%s: too high compensation count %d\n",
342 			__func__, compen_count);
343 		compen_count = IEP_MAX_COMPEN_COUNT;
344 	}
345 
346 	regmap_write(iep->map, ICSS_IEP_COMPEN_REG, compen_count);
347 }
348 
349 static void icss_iep_set_slow_compensation_count(struct icss_iep *iep,
350 						 u32 compen_count)
351 {
352 	regmap_write(iep->map, ICSS_IEP_SLOW_COMPEN_REG, compen_count);
353 }
354 
355 /* PTP PHC operations */
356 static int icss_iep_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
357 {
358 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
359 	s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
360 	u32 cyc_count;
361 	u16 cmp_inc;
362 
363 	mutex_lock(&iep->ptp_clk_mutex);
364 
365 	/* ppb is amount of frequency we want to adjust in 1GHz (billion)
366 	 * e.g. 100ppb means we need to speed up clock by 100Hz
367 	 * i.e. at end of 1 second (1 billion ns) clock time, we should be
368 	 * counting 100 more ns.
369 	 * We use IEP slow compensation to achieve continuous freq. adjustment.
370 	 * There are 2 parts. Cycle time and adjustment per cycle.
371 	 * Simplest case would be 1 sec Cycle time. Then adjustment
372 	 * pre cycle would be (def_inc + ppb) value.
373 	 * Cycle time will have to be chosen based on how worse the ppb is.
374 	 * e.g. smaller the ppb, cycle time has to be large.
375 	 * The minimum adjustment we can do is +-1ns per cycle so let's
376 	 * reduce the cycle time to get 1ns per cycle adjustment.
377 	 *	1ppb = 1sec cycle time & 1ns adjust
378 	 *	1000ppb = 1/1000 cycle time & 1ns adjust per cycle
379 	 */
380 
381 	if (iep->cycle_time_ns)
382 		iep->slow_cmp_inc = iep->clk_tick_time;	/* 4ns adj per cycle */
383 	else
384 		iep->slow_cmp_inc = 1;	/* 1ns adjust per cycle */
385 
386 	if (ppb < 0) {
387 		iep->slow_cmp_inc = -iep->slow_cmp_inc;
388 		ppb = -ppb;
389 	}
390 
391 	cyc_count = NSEC_PER_SEC;		/* 1s cycle time @1GHz */
392 	cyc_count /= ppb;		/* cycle time per ppb */
393 
394 	/* slow_cmp_count is decremented every clock cycle, e.g. @250MHz */
395 	if (!iep->cycle_time_ns)
396 		cyc_count /= iep->clk_tick_time;
397 	iep->slow_cmp_count = cyc_count;
398 
399 	/* iep->clk_tick_time is def_inc */
400 	cmp_inc = iep->clk_tick_time + iep->slow_cmp_inc;
401 	icss_iep_set_compensation_inc(iep, cmp_inc);
402 	icss_iep_set_slow_compensation_count(iep, iep->slow_cmp_count);
403 
404 	mutex_unlock(&iep->ptp_clk_mutex);
405 
406 	return 0;
407 }
408 
409 static int icss_iep_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
410 {
411 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
412 	s64 ns;
413 
414 	mutex_lock(&iep->ptp_clk_mutex);
415 	if (iep->ops && iep->ops->adjtime) {
416 		iep->ops->adjtime(iep->clockops_data, delta);
417 	} else {
418 		ns = icss_iep_gettime(iep, NULL);
419 		ns += delta;
420 		icss_iep_settime(iep, ns);
421 	}
422 	mutex_unlock(&iep->ptp_clk_mutex);
423 
424 	return 0;
425 }
426 
427 static int icss_iep_ptp_gettimeex(struct ptp_clock_info *ptp,
428 				  struct timespec64 *ts,
429 				  struct ptp_system_timestamp *sts)
430 {
431 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
432 	u64 ns;
433 
434 	mutex_lock(&iep->ptp_clk_mutex);
435 	ns = icss_iep_gettime(iep, sts);
436 	*ts = ns_to_timespec64(ns);
437 	mutex_unlock(&iep->ptp_clk_mutex);
438 
439 	return 0;
440 }
441 
442 static int icss_iep_ptp_settime(struct ptp_clock_info *ptp,
443 				const struct timespec64 *ts)
444 {
445 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
446 	u64 ns;
447 
448 	mutex_lock(&iep->ptp_clk_mutex);
449 	ns = timespec64_to_ns(ts);
450 	icss_iep_settime(iep, ns);
451 	mutex_unlock(&iep->ptp_clk_mutex);
452 
453 	return 0;
454 }
455 
456 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
457 {
458 	u64 ns, p_ns;
459 	u32 offset;
460 
461 	ns = icss_iep_gettime(iep, NULL);
462 	if (start_ns < ns)
463 		start_ns = ns;
464 	p_ns = iep->period;
465 	/* Round up to next period boundary */
466 	start_ns += p_ns - 1;
467 	offset = do_div(start_ns, p_ns);
468 	start_ns = start_ns * p_ns;
469 	/* If it is too close to update, shift to next boundary */
470 	if (p_ns - offset < 10)
471 		start_ns += p_ns;
472 
473 	regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(start_ns));
474 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
475 		regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(start_ns));
476 }
477 
478 static int icss_iep_perout_enable_hw(struct icss_iep *iep,
479 				     struct ptp_perout_request *req, int on)
480 {
481 	int ret;
482 	u64 cmp;
483 
484 	if (iep->ops && iep->ops->perout_enable) {
485 		ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
486 		if (ret)
487 			return ret;
488 
489 		if (on) {
490 			/* Configure CMP */
491 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
492 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
493 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
494 			/* Configure SYNC, 1ms pulse width */
495 			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, 1000000);
496 			regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
497 			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
498 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
499 			/* Enable CMP 1 */
500 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
501 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
502 		} else {
503 			/* Disable CMP 1 */
504 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
505 					   IEP_CMP_CFG_CMP_EN(1), 0);
506 
507 			/* clear regs */
508 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
509 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
510 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
511 		}
512 	} else {
513 		if (on) {
514 			u64 start_ns;
515 
516 			iep->period = ((u64)req->period.sec * NSEC_PER_SEC) +
517 				      req->period.nsec;
518 			start_ns = ((u64)req->period.sec * NSEC_PER_SEC)
519 				   + req->period.nsec;
520 			icss_iep_update_to_next_boundary(iep, start_ns);
521 
522 			/* Enable Sync in single shot mode  */
523 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
524 				     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
525 			/* Enable CMP 1 */
526 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
527 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
528 		} else {
529 			/* Disable CMP 1 */
530 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
531 					   IEP_CMP_CFG_CMP_EN(1), 0);
532 
533 			/* clear CMP regs */
534 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
535 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
536 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
537 
538 			/* Disable sync */
539 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0);
540 		}
541 	}
542 
543 	return 0;
544 }
545 
546 static int icss_iep_perout_enable(struct icss_iep *iep,
547 				  struct ptp_perout_request *req, int on)
548 {
549 	unsigned long flags;
550 	int ret = 0;
551 
552 	mutex_lock(&iep->ptp_clk_mutex);
553 
554 	if (iep->pps_enabled) {
555 		ret = -EBUSY;
556 		goto exit;
557 	}
558 
559 	if (iep->perout_enabled == !!on)
560 		goto exit;
561 
562 	spin_lock_irqsave(&iep->irq_lock, flags);
563 	ret = icss_iep_perout_enable_hw(iep, req, on);
564 	if (!ret)
565 		iep->perout_enabled = !!on;
566 	spin_unlock_irqrestore(&iep->irq_lock, flags);
567 
568 exit:
569 	mutex_unlock(&iep->ptp_clk_mutex);
570 
571 	return ret;
572 }
573 
574 static int icss_iep_pps_enable(struct icss_iep *iep, int on)
575 {
576 	struct ptp_clock_request rq;
577 	struct timespec64 ts;
578 	unsigned long flags;
579 	int ret = 0;
580 	u64 ns;
581 
582 	mutex_lock(&iep->ptp_clk_mutex);
583 
584 	if (iep->perout_enabled) {
585 		ret = -EBUSY;
586 		goto exit;
587 	}
588 
589 	if (iep->pps_enabled == !!on)
590 		goto exit;
591 
592 	spin_lock_irqsave(&iep->irq_lock, flags);
593 
594 	rq.perout.index = 0;
595 	if (on) {
596 		ns = icss_iep_gettime(iep, NULL);
597 		ts = ns_to_timespec64(ns);
598 		rq.perout.period.sec = 1;
599 		rq.perout.period.nsec = 0;
600 		rq.perout.start.sec = ts.tv_sec + 2;
601 		rq.perout.start.nsec = 0;
602 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
603 	} else {
604 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
605 	}
606 
607 	if (!ret)
608 		iep->pps_enabled = !!on;
609 
610 	spin_unlock_irqrestore(&iep->irq_lock, flags);
611 
612 exit:
613 	mutex_unlock(&iep->ptp_clk_mutex);
614 
615 	return ret;
616 }
617 
618 static int icss_iep_extts_enable(struct icss_iep *iep, u32 index, int on)
619 {
620 	u32 val, cap, ret = 0;
621 
622 	mutex_lock(&iep->ptp_clk_mutex);
623 
624 	if (iep->ops && iep->ops->extts_enable) {
625 		ret = iep->ops->extts_enable(iep->clockops_data, index, on);
626 		goto exit;
627 	}
628 
629 	if (((iep->latch_enable & BIT(index)) >> index) == on)
630 		goto exit;
631 
632 	regmap_read(iep->map, ICSS_IEP_CAPTURE_CFG_REG, &val);
633 	cap = IEP_CAP_CFG_CAP_ASYNC_EN(index) | IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(index);
634 	if (on) {
635 		val |= cap;
636 		iep->latch_enable |= BIT(index);
637 	} else {
638 		val &= ~cap;
639 		iep->latch_enable &= ~BIT(index);
640 	}
641 	regmap_write(iep->map, ICSS_IEP_CAPTURE_CFG_REG, val);
642 
643 exit:
644 	mutex_unlock(&iep->ptp_clk_mutex);
645 
646 	return ret;
647 }
648 
649 static int icss_iep_ptp_enable(struct ptp_clock_info *ptp,
650 			       struct ptp_clock_request *rq, int on)
651 {
652 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
653 
654 	switch (rq->type) {
655 	case PTP_CLK_REQ_PEROUT:
656 		return icss_iep_perout_enable(iep, &rq->perout, on);
657 	case PTP_CLK_REQ_PPS:
658 		return icss_iep_pps_enable(iep, on);
659 	case PTP_CLK_REQ_EXTTS:
660 		return icss_iep_extts_enable(iep, rq->extts.index, on);
661 	default:
662 		break;
663 	}
664 
665 	return -EOPNOTSUPP;
666 }
667 
668 static struct ptp_clock_info icss_iep_ptp_info = {
669 	.owner		= THIS_MODULE,
670 	.name		= "ICSS IEP timer",
671 	.max_adj	= 10000000,
672 	.adjfine	= icss_iep_ptp_adjfine,
673 	.adjtime	= icss_iep_ptp_adjtime,
674 	.gettimex64	= icss_iep_ptp_gettimeex,
675 	.settime64	= icss_iep_ptp_settime,
676 	.enable		= icss_iep_ptp_enable,
677 };
678 
679 struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx)
680 {
681 	struct platform_device *pdev;
682 	struct device_node *iep_np;
683 	struct icss_iep *iep;
684 
685 	iep_np = of_parse_phandle(np, "ti,iep", idx);
686 	if (!iep_np || !of_device_is_available(iep_np))
687 		return ERR_PTR(-ENODEV);
688 
689 	pdev = of_find_device_by_node(iep_np);
690 	of_node_put(iep_np);
691 
692 	if (!pdev)
693 		/* probably IEP not yet probed */
694 		return ERR_PTR(-EPROBE_DEFER);
695 
696 	iep = platform_get_drvdata(pdev);
697 	if (!iep)
698 		return ERR_PTR(-EPROBE_DEFER);
699 
700 	device_lock(iep->dev);
701 	if (iep->client_np) {
702 		device_unlock(iep->dev);
703 		dev_err(iep->dev, "IEP is already acquired by %s",
704 			iep->client_np->name);
705 		return ERR_PTR(-EBUSY);
706 	}
707 	iep->client_np = np;
708 	device_unlock(iep->dev);
709 	get_device(iep->dev);
710 
711 	return iep;
712 }
713 EXPORT_SYMBOL_GPL(icss_iep_get_idx);
714 
715 struct icss_iep *icss_iep_get(struct device_node *np)
716 {
717 	return icss_iep_get_idx(np, 0);
718 }
719 EXPORT_SYMBOL_GPL(icss_iep_get);
720 
721 void icss_iep_put(struct icss_iep *iep)
722 {
723 	device_lock(iep->dev);
724 	iep->client_np = NULL;
725 	device_unlock(iep->dev);
726 	put_device(iep->dev);
727 }
728 EXPORT_SYMBOL_GPL(icss_iep_put);
729 
730 void icss_iep_init_fw(struct icss_iep *iep)
731 {
732 	/* start IEP for FW use in raw 64bit mode, no PTP support */
733 	iep->clk_tick_time = iep->def_inc;
734 	iep->cycle_time_ns = 0;
735 	iep->ops = NULL;
736 	iep->clockops_data = NULL;
737 	icss_iep_set_default_inc(iep, iep->def_inc);
738 	icss_iep_set_compensation_inc(iep, iep->def_inc);
739 	icss_iep_set_compensation_count(iep, 0);
740 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
741 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
742 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
743 		icss_iep_set_slow_compensation_count(iep, 0);
744 
745 	icss_iep_enable(iep);
746 	icss_iep_settime(iep, 0);
747 }
748 EXPORT_SYMBOL_GPL(icss_iep_init_fw);
749 
750 void icss_iep_exit_fw(struct icss_iep *iep)
751 {
752 	icss_iep_disable(iep);
753 }
754 EXPORT_SYMBOL_GPL(icss_iep_exit_fw);
755 
756 int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
757 		  void *clockops_data, u32 cycle_time_ns)
758 {
759 	int ret = 0;
760 
761 	iep->cycle_time_ns = cycle_time_ns;
762 	iep->clk_tick_time = iep->def_inc;
763 	iep->ops = clkops;
764 	iep->clockops_data = clockops_data;
765 	icss_iep_set_default_inc(iep, iep->def_inc);
766 	icss_iep_set_compensation_inc(iep, iep->def_inc);
767 	icss_iep_set_compensation_count(iep, 0);
768 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
769 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
770 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
771 		icss_iep_set_slow_compensation_count(iep, 0);
772 
773 	if (!(iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) ||
774 	    !(iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT))
775 		goto skip_perout;
776 
777 	if (iep->ops && iep->ops->perout_enable) {
778 		iep->ptp_info.n_per_out = 1;
779 		iep->ptp_info.pps = 1;
780 	}
781 
782 	if (iep->ops && iep->ops->extts_enable)
783 		iep->ptp_info.n_ext_ts = 2;
784 
785 skip_perout:
786 	if (cycle_time_ns)
787 		icss_iep_enable_shadow_mode(iep);
788 	else
789 		icss_iep_enable(iep);
790 	icss_iep_settime(iep, ktime_get_real_ns());
791 
792 	iep->ptp_clock = ptp_clock_register(&iep->ptp_info, iep->dev);
793 	if (IS_ERR(iep->ptp_clock)) {
794 		ret = PTR_ERR(iep->ptp_clock);
795 		iep->ptp_clock = NULL;
796 		dev_err(iep->dev, "Failed to register ptp clk %d\n", ret);
797 	}
798 
799 	return ret;
800 }
801 EXPORT_SYMBOL_GPL(icss_iep_init);
802 
803 int icss_iep_exit(struct icss_iep *iep)
804 {
805 	if (iep->ptp_clock) {
806 		ptp_clock_unregister(iep->ptp_clock);
807 		iep->ptp_clock = NULL;
808 	}
809 	icss_iep_disable(iep);
810 
811 	return 0;
812 }
813 EXPORT_SYMBOL_GPL(icss_iep_exit);
814 
815 static int icss_iep_probe(struct platform_device *pdev)
816 {
817 	struct device *dev = &pdev->dev;
818 	struct icss_iep *iep;
819 	struct clk *iep_clk;
820 
821 	iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
822 	if (!iep)
823 		return -ENOMEM;
824 
825 	iep->dev = dev;
826 	iep->base = devm_platform_ioremap_resource(pdev, 0);
827 	if (IS_ERR(iep->base))
828 		return -ENODEV;
829 
830 	iep_clk = devm_clk_get(dev, NULL);
831 	if (IS_ERR(iep_clk))
832 		return PTR_ERR(iep_clk);
833 
834 	iep->refclk_freq = clk_get_rate(iep_clk);
835 
836 	iep->def_inc = NSEC_PER_SEC / iep->refclk_freq;	/* ns per clock tick */
837 	if (iep->def_inc > IEP_MAX_DEF_INC) {
838 		dev_err(dev, "Failed to set def_inc %d.  IEP_clock is too slow to be supported\n",
839 			iep->def_inc);
840 		return -EINVAL;
841 	}
842 
843 	iep->plat_data = device_get_match_data(dev);
844 	if (!iep->plat_data)
845 		return -EINVAL;
846 
847 	iep->map = devm_regmap_init(dev, NULL, iep, iep->plat_data->config);
848 	if (IS_ERR(iep->map)) {
849 		dev_err(dev, "Failed to create regmap for IEP %ld\n",
850 			PTR_ERR(iep->map));
851 		return PTR_ERR(iep->map);
852 	}
853 
854 	iep->ptp_info = icss_iep_ptp_info;
855 	mutex_init(&iep->ptp_clk_mutex);
856 	spin_lock_init(&iep->irq_lock);
857 	dev_set_drvdata(dev, iep);
858 	icss_iep_disable(iep);
859 
860 	return 0;
861 }
862 
863 static bool am654_icss_iep_valid_reg(struct device *dev, unsigned int reg)
864 {
865 	switch (reg) {
866 	case ICSS_IEP_GLOBAL_CFG_REG ... ICSS_IEP_SYNC_START_REG:
867 		return true;
868 	default:
869 		return false;
870 	}
871 
872 	return false;
873 }
874 
875 static int icss_iep_regmap_write(void *context, unsigned int reg,
876 				 unsigned int val)
877 {
878 	struct icss_iep *iep = context;
879 
880 	writel(val, iep->base + iep->plat_data->reg_offs[reg]);
881 
882 	return 0;
883 }
884 
885 static int icss_iep_regmap_read(void *context, unsigned int reg,
886 				unsigned int *val)
887 {
888 	struct icss_iep *iep = context;
889 
890 	*val = readl(iep->base + iep->plat_data->reg_offs[reg]);
891 
892 	return 0;
893 }
894 
895 static struct regmap_config am654_icss_iep_regmap_config = {
896 	.name = "icss iep",
897 	.reg_stride = 1,
898 	.reg_write = icss_iep_regmap_write,
899 	.reg_read = icss_iep_regmap_read,
900 	.writeable_reg = am654_icss_iep_valid_reg,
901 	.readable_reg = am654_icss_iep_valid_reg,
902 	.fast_io = 1,
903 };
904 
905 static const struct icss_iep_plat_data am654_icss_iep_plat_data = {
906 	.flags = ICSS_IEP_64BIT_COUNTER_SUPPORT |
907 		 ICSS_IEP_SLOW_COMPEN_REG_SUPPORT |
908 		 ICSS_IEP_SHADOW_MODE_SUPPORT,
909 	.reg_offs = {
910 		[ICSS_IEP_GLOBAL_CFG_REG] = 0x00,
911 		[ICSS_IEP_COMPEN_REG] = 0x08,
912 		[ICSS_IEP_SLOW_COMPEN_REG] = 0x0C,
913 		[ICSS_IEP_COUNT_REG0] = 0x10,
914 		[ICSS_IEP_COUNT_REG1] = 0x14,
915 		[ICSS_IEP_CAPTURE_CFG_REG] = 0x18,
916 		[ICSS_IEP_CAPTURE_STAT_REG] = 0x1c,
917 
918 		[ICSS_IEP_CAP6_RISE_REG0] = 0x50,
919 		[ICSS_IEP_CAP6_RISE_REG1] = 0x54,
920 
921 		[ICSS_IEP_CAP7_RISE_REG0] = 0x60,
922 		[ICSS_IEP_CAP7_RISE_REG1] = 0x64,
923 
924 		[ICSS_IEP_CMP_CFG_REG] = 0x70,
925 		[ICSS_IEP_CMP_STAT_REG] = 0x74,
926 		[ICSS_IEP_CMP0_REG0] = 0x78,
927 		[ICSS_IEP_CMP0_REG1] = 0x7c,
928 		[ICSS_IEP_CMP1_REG0] = 0x80,
929 		[ICSS_IEP_CMP1_REG1] = 0x84,
930 
931 		[ICSS_IEP_CMP8_REG0] = 0xc0,
932 		[ICSS_IEP_CMP8_REG1] = 0xc4,
933 		[ICSS_IEP_SYNC_CTRL_REG] = 0x180,
934 		[ICSS_IEP_SYNC0_STAT_REG] = 0x188,
935 		[ICSS_IEP_SYNC1_STAT_REG] = 0x18c,
936 		[ICSS_IEP_SYNC_PWIDTH_REG] = 0x190,
937 		[ICSS_IEP_SYNC0_PERIOD_REG] = 0x194,
938 		[ICSS_IEP_SYNC1_DELAY_REG] = 0x198,
939 		[ICSS_IEP_SYNC_START_REG] = 0x19c,
940 	},
941 	.config = &am654_icss_iep_regmap_config,
942 };
943 
944 static const struct of_device_id icss_iep_of_match[] = {
945 	{
946 		.compatible = "ti,am654-icss-iep",
947 		.data = &am654_icss_iep_plat_data,
948 	},
949 	{},
950 };
951 MODULE_DEVICE_TABLE(of, icss_iep_of_match);
952 
953 static struct platform_driver icss_iep_driver = {
954 	.driver = {
955 		.name = "icss-iep",
956 		.of_match_table = icss_iep_of_match,
957 	},
958 	.probe = icss_iep_probe,
959 };
960 module_platform_driver(icss_iep_driver);
961 
962 MODULE_LICENSE("GPL");
963 MODULE_DESCRIPTION("TI ICSS IEP driver");
964 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
965 MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
966