xref: /openbmc/linux/drivers/net/ethernet/ti/icssg/icss_iep.c (revision 973421d5862b2297c5d63731c6f313e9a60b0674)
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 	u32 def_inc;
114 	s16 slow_cmp_inc;
115 	u32 slow_cmp_count;
116 	const struct icss_iep_clockops *ops;
117 	void *clockops_data;
118 	u32 cycle_time_ns;
119 	u32 perout_enabled;
120 	bool pps_enabled;
121 	int cap_cmp_irq;
122 	u64 period;
123 	u32 latch_enable;
124 };
125 
126 /**
127  * icss_iep_get_count_hi() - Get the upper 32 bit IEP counter
128  * @iep: Pointer to structure representing IEP.
129  *
130  * Return: upper 32 bit IEP counter
131  */
132 int icss_iep_get_count_hi(struct icss_iep *iep)
133 {
134 	u32 val = 0;
135 
136 	if (iep && (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT))
137 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
138 
139 	return val;
140 }
141 EXPORT_SYMBOL_GPL(icss_iep_get_count_hi);
142 
143 /**
144  * icss_iep_get_count_low() - Get the lower 32 bit IEP counter
145  * @iep: Pointer to structure representing IEP.
146  *
147  * Return: lower 32 bit IEP counter
148  */
149 int icss_iep_get_count_low(struct icss_iep *iep)
150 {
151 	u32 val = 0;
152 
153 	if (iep)
154 		val = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
155 
156 	return val;
157 }
158 EXPORT_SYMBOL_GPL(icss_iep_get_count_low);
159 
160 /**
161  * icss_iep_get_ptp_clock_idx() - Get PTP clock index using IEP driver
162  * @iep: Pointer to structure representing IEP.
163  *
164  * Return: PTP clock index, -1 if not registered
165  */
166 int icss_iep_get_ptp_clock_idx(struct icss_iep *iep)
167 {
168 	if (!iep || !iep->ptp_clock)
169 		return -1;
170 	return ptp_clock_index(iep->ptp_clock);
171 }
172 EXPORT_SYMBOL_GPL(icss_iep_get_ptp_clock_idx);
173 
174 static void icss_iep_set_counter(struct icss_iep *iep, u64 ns)
175 {
176 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
177 		writel(upper_32_bits(ns), iep->base +
178 		       iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
179 	writel(lower_32_bits(ns), iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
180 }
181 
182 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns);
183 
184 /**
185  * icss_iep_settime() - Set time of the PTP clock using IEP driver
186  * @iep: Pointer to structure representing IEP.
187  * @ns: Time to be set in nanoseconds
188  *
189  * This API uses writel() instead of regmap_write() for write operations as
190  * regmap_write() is too slow and this API is time sensitive.
191  */
192 static void icss_iep_settime(struct icss_iep *iep, u64 ns)
193 {
194 	if (iep->ops && iep->ops->settime) {
195 		iep->ops->settime(iep->clockops_data, ns);
196 		return;
197 	}
198 
199 	if (iep->pps_enabled || iep->perout_enabled)
200 		writel(0, iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
201 
202 	icss_iep_set_counter(iep, ns);
203 
204 	if (iep->pps_enabled || iep->perout_enabled) {
205 		icss_iep_update_to_next_boundary(iep, ns);
206 		writel(IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN,
207 		       iep->base + iep->plat_data->reg_offs[ICSS_IEP_SYNC_CTRL_REG]);
208 	}
209 }
210 
211 /**
212  * icss_iep_gettime() - Get time of the PTP clock using IEP driver
213  * @iep: Pointer to structure representing IEP.
214  * @sts: Pointer to structure representing PTP system timestamp.
215  *
216  * This API uses readl() instead of regmap_read() for read operations as
217  * regmap_read() is too slow and this API is time sensitive.
218  *
219  * Return: The current timestamp of the PTP clock using IEP driver
220  */
221 static u64 icss_iep_gettime(struct icss_iep *iep,
222 			    struct ptp_system_timestamp *sts)
223 {
224 	u32 ts_hi = 0, ts_lo;
225 	unsigned long flags;
226 
227 	if (iep->ops && iep->ops->gettime)
228 		return iep->ops->gettime(iep->clockops_data, sts);
229 
230 	/* use local_irq_x() to make it work for both RT/non-RT */
231 	local_irq_save(flags);
232 
233 	/* no need to play with hi-lo, hi is latched when lo is read */
234 	ptp_read_system_prets(sts);
235 	ts_lo = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG0]);
236 	ptp_read_system_postts(sts);
237 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
238 		ts_hi = readl(iep->base + iep->plat_data->reg_offs[ICSS_IEP_COUNT_REG1]);
239 
240 	local_irq_restore(flags);
241 
242 	return (u64)ts_lo | (u64)ts_hi << 32;
243 }
244 
245 static void icss_iep_enable(struct icss_iep *iep)
246 {
247 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
248 			   IEP_GLOBAL_CFG_CNT_ENABLE,
249 			   IEP_GLOBAL_CFG_CNT_ENABLE);
250 }
251 
252 static void icss_iep_disable(struct icss_iep *iep)
253 {
254 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
255 			   IEP_GLOBAL_CFG_CNT_ENABLE,
256 			   0);
257 }
258 
259 static void icss_iep_enable_shadow_mode(struct icss_iep *iep)
260 {
261 	u32 cycle_time;
262 	int cmp;
263 
264 	cycle_time = iep->cycle_time_ns - iep->def_inc;
265 
266 	icss_iep_disable(iep);
267 
268 	/* disable shadow mode */
269 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
270 			   IEP_CMP_CFG_SHADOW_EN, 0);
271 
272 	/* enable shadow mode */
273 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
274 			   IEP_CMP_CFG_SHADOW_EN, IEP_CMP_CFG_SHADOW_EN);
275 
276 	/* clear counters */
277 	icss_iep_set_counter(iep, 0);
278 
279 	/* clear overflow status */
280 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_STATUS_REG,
281 			   IEP_GLOBAL_STATUS_CNT_OVF,
282 			   IEP_GLOBAL_STATUS_CNT_OVF);
283 
284 	/* clear compare status */
285 	for (cmp = IEP_MIN_CMP; cmp < IEP_MAX_CMP; cmp++) {
286 		regmap_update_bits(iep->map, ICSS_IEP_CMP_STAT_REG,
287 				   IEP_CMP_STATUS(cmp), IEP_CMP_STATUS(cmp));
288 
289 		regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
290 				   IEP_CMP_CFG_CMP_EN(cmp), 0);
291 	}
292 
293 	/* enable reset counter on CMP0 event */
294 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
295 			   IEP_CMP_CFG_CMP0_RST_CNT_EN,
296 			   IEP_CMP_CFG_CMP0_RST_CNT_EN);
297 	/* enable compare */
298 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
299 			   IEP_CMP_CFG_CMP_EN(0),
300 			   IEP_CMP_CFG_CMP_EN(0));
301 
302 	/* set CMP0 value to cycle time */
303 	regmap_write(iep->map, ICSS_IEP_CMP0_REG0, cycle_time);
304 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
305 		regmap_write(iep->map, ICSS_IEP_CMP0_REG1, cycle_time);
306 
307 	icss_iep_set_counter(iep, 0);
308 	icss_iep_enable(iep);
309 }
310 
311 static void icss_iep_set_default_inc(struct icss_iep *iep, u8 def_inc)
312 {
313 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
314 			   IEP_GLOBAL_CFG_DEFAULT_INC_MASK,
315 			   def_inc << IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT);
316 }
317 
318 static void icss_iep_set_compensation_inc(struct icss_iep *iep, u16 compen_inc)
319 {
320 	struct device *dev = regmap_get_device(iep->map);
321 
322 	if (compen_inc > IEP_MAX_COMPEN_INC) {
323 		dev_err(dev, "%s: too high compensation inc %d\n",
324 			__func__, compen_inc);
325 		compen_inc = IEP_MAX_COMPEN_INC;
326 	}
327 
328 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
329 			   IEP_GLOBAL_CFG_COMPEN_INC_MASK,
330 			   compen_inc << IEP_GLOBAL_CFG_COMPEN_INC_SHIFT);
331 }
332 
333 static void icss_iep_set_compensation_count(struct icss_iep *iep,
334 					    u32 compen_count)
335 {
336 	struct device *dev = regmap_get_device(iep->map);
337 
338 	if (compen_count > IEP_MAX_COMPEN_COUNT) {
339 		dev_err(dev, "%s: too high compensation count %d\n",
340 			__func__, compen_count);
341 		compen_count = IEP_MAX_COMPEN_COUNT;
342 	}
343 
344 	regmap_write(iep->map, ICSS_IEP_COMPEN_REG, compen_count);
345 }
346 
347 static void icss_iep_set_slow_compensation_count(struct icss_iep *iep,
348 						 u32 compen_count)
349 {
350 	regmap_write(iep->map, ICSS_IEP_SLOW_COMPEN_REG, compen_count);
351 }
352 
353 /* PTP PHC operations */
354 static int icss_iep_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
355 {
356 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
357 	s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
358 	u32 cyc_count;
359 	u16 cmp_inc;
360 
361 	mutex_lock(&iep->ptp_clk_mutex);
362 
363 	/* ppb is amount of frequency we want to adjust in 1GHz (billion)
364 	 * e.g. 100ppb means we need to speed up clock by 100Hz
365 	 * i.e. at end of 1 second (1 billion ns) clock time, we should be
366 	 * counting 100 more ns.
367 	 * We use IEP slow compensation to achieve continuous freq. adjustment.
368 	 * There are 2 parts. Cycle time and adjustment per cycle.
369 	 * Simplest case would be 1 sec Cycle time. Then adjustment
370 	 * pre cycle would be (def_inc + ppb) value.
371 	 * Cycle time will have to be chosen based on how worse the ppb is.
372 	 * e.g. smaller the ppb, cycle time has to be large.
373 	 * The minimum adjustment we can do is +-1ns per cycle so let's
374 	 * reduce the cycle time to get 1ns per cycle adjustment.
375 	 *	1ppb = 1sec cycle time & 1ns adjust
376 	 *	1000ppb = 1/1000 cycle time & 1ns adjust per cycle
377 	 */
378 
379 	if (iep->cycle_time_ns)
380 		iep->slow_cmp_inc = iep->clk_tick_time;	/* 4ns adj per cycle */
381 	else
382 		iep->slow_cmp_inc = 1;	/* 1ns adjust per cycle */
383 
384 	if (ppb < 0) {
385 		iep->slow_cmp_inc = -iep->slow_cmp_inc;
386 		ppb = -ppb;
387 	}
388 
389 	cyc_count = NSEC_PER_SEC;		/* 1s cycle time @1GHz */
390 	cyc_count /= ppb;		/* cycle time per ppb */
391 
392 	/* slow_cmp_count is decremented every clock cycle, e.g. @250MHz */
393 	if (!iep->cycle_time_ns)
394 		cyc_count /= iep->clk_tick_time;
395 	iep->slow_cmp_count = cyc_count;
396 
397 	/* iep->clk_tick_time is def_inc */
398 	cmp_inc = iep->clk_tick_time + iep->slow_cmp_inc;
399 	icss_iep_set_compensation_inc(iep, cmp_inc);
400 	icss_iep_set_slow_compensation_count(iep, iep->slow_cmp_count);
401 
402 	mutex_unlock(&iep->ptp_clk_mutex);
403 
404 	return 0;
405 }
406 
407 static int icss_iep_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
408 {
409 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
410 	s64 ns;
411 
412 	mutex_lock(&iep->ptp_clk_mutex);
413 	if (iep->ops && iep->ops->adjtime) {
414 		iep->ops->adjtime(iep->clockops_data, delta);
415 	} else {
416 		ns = icss_iep_gettime(iep, NULL);
417 		ns += delta;
418 		icss_iep_settime(iep, ns);
419 	}
420 	mutex_unlock(&iep->ptp_clk_mutex);
421 
422 	return 0;
423 }
424 
425 static int icss_iep_ptp_gettimeex(struct ptp_clock_info *ptp,
426 				  struct timespec64 *ts,
427 				  struct ptp_system_timestamp *sts)
428 {
429 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
430 	u64 ns;
431 
432 	mutex_lock(&iep->ptp_clk_mutex);
433 	ns = icss_iep_gettime(iep, sts);
434 	*ts = ns_to_timespec64(ns);
435 	mutex_unlock(&iep->ptp_clk_mutex);
436 
437 	return 0;
438 }
439 
440 static int icss_iep_ptp_settime(struct ptp_clock_info *ptp,
441 				const struct timespec64 *ts)
442 {
443 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
444 	u64 ns;
445 
446 	mutex_lock(&iep->ptp_clk_mutex);
447 	ns = timespec64_to_ns(ts);
448 	icss_iep_settime(iep, ns);
449 	mutex_unlock(&iep->ptp_clk_mutex);
450 
451 	return 0;
452 }
453 
454 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
455 {
456 	u64 ns, p_ns;
457 	u32 offset;
458 
459 	ns = icss_iep_gettime(iep, NULL);
460 	if (start_ns < ns)
461 		start_ns = ns;
462 	p_ns = iep->period;
463 	/* Round up to next period boundary */
464 	start_ns += p_ns - 1;
465 	offset = do_div(start_ns, p_ns);
466 	start_ns = start_ns * p_ns;
467 	/* If it is too close to update, shift to next boundary */
468 	if (p_ns - offset < 10)
469 		start_ns += p_ns;
470 
471 	regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(start_ns));
472 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
473 		regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(start_ns));
474 }
475 
476 static int icss_iep_perout_enable_hw(struct icss_iep *iep,
477 				     struct ptp_perout_request *req, int on)
478 {
479 	int ret;
480 	u64 cmp;
481 
482 	if (iep->ops && iep->ops->perout_enable) {
483 		ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
484 		if (ret)
485 			return ret;
486 
487 		if (on) {
488 			/* Configure CMP */
489 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
490 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
491 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
492 			/* Configure SYNC, 1ms pulse width */
493 			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, 1000000);
494 			regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
495 			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG, 0);
496 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
497 			/* Enable CMP 1 */
498 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
499 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
500 		} else {
501 			/* Disable CMP 1 */
502 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
503 					   IEP_CMP_CFG_CMP_EN(1), 0);
504 
505 			/* clear regs */
506 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
507 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
508 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
509 		}
510 	} else {
511 		if (on) {
512 			u64 start_ns;
513 
514 			iep->period = ((u64)req->period.sec * NSEC_PER_SEC) +
515 				      req->period.nsec;
516 			start_ns = ((u64)req->period.sec * NSEC_PER_SEC)
517 				   + req->period.nsec;
518 			icss_iep_update_to_next_boundary(iep, start_ns);
519 
520 			/* Enable Sync in single shot mode  */
521 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
522 				     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
523 			/* Enable CMP 1 */
524 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
525 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
526 		} else {
527 			/* Disable CMP 1 */
528 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
529 					   IEP_CMP_CFG_CMP_EN(1), 0);
530 
531 			/* clear CMP regs */
532 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
533 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
534 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
535 
536 			/* Disable sync */
537 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0);
538 		}
539 	}
540 
541 	return 0;
542 }
543 
544 static int icss_iep_perout_enable(struct icss_iep *iep,
545 				  struct ptp_perout_request *req, int on)
546 {
547 	return -EOPNOTSUPP;
548 }
549 
550 static int icss_iep_pps_enable(struct icss_iep *iep, int on)
551 {
552 	struct ptp_clock_request rq;
553 	struct timespec64 ts;
554 	int ret = 0;
555 	u64 ns;
556 
557 	mutex_lock(&iep->ptp_clk_mutex);
558 
559 	if (iep->perout_enabled) {
560 		ret = -EBUSY;
561 		goto exit;
562 	}
563 
564 	if (iep->pps_enabled == !!on)
565 		goto exit;
566 
567 	rq.perout.index = 0;
568 	if (on) {
569 		ns = icss_iep_gettime(iep, NULL);
570 		ts = ns_to_timespec64(ns);
571 		rq.perout.period.sec = 1;
572 		rq.perout.period.nsec = 0;
573 		rq.perout.start.sec = ts.tv_sec + 2;
574 		rq.perout.start.nsec = 0;
575 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
576 	} else {
577 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
578 	}
579 
580 	if (!ret)
581 		iep->pps_enabled = !!on;
582 
583 exit:
584 	mutex_unlock(&iep->ptp_clk_mutex);
585 
586 	return ret;
587 }
588 
589 static int icss_iep_extts_enable(struct icss_iep *iep, u32 index, int on)
590 {
591 	u32 val, cap, ret = 0;
592 
593 	mutex_lock(&iep->ptp_clk_mutex);
594 
595 	if (iep->ops && iep->ops->extts_enable) {
596 		ret = iep->ops->extts_enable(iep->clockops_data, index, on);
597 		goto exit;
598 	}
599 
600 	if (((iep->latch_enable & BIT(index)) >> index) == on)
601 		goto exit;
602 
603 	regmap_read(iep->map, ICSS_IEP_CAPTURE_CFG_REG, &val);
604 	cap = IEP_CAP_CFG_CAP_ASYNC_EN(index) | IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(index);
605 	if (on) {
606 		val |= cap;
607 		iep->latch_enable |= BIT(index);
608 	} else {
609 		val &= ~cap;
610 		iep->latch_enable &= ~BIT(index);
611 	}
612 	regmap_write(iep->map, ICSS_IEP_CAPTURE_CFG_REG, val);
613 
614 exit:
615 	mutex_unlock(&iep->ptp_clk_mutex);
616 
617 	return ret;
618 }
619 
620 static int icss_iep_ptp_enable(struct ptp_clock_info *ptp,
621 			       struct ptp_clock_request *rq, int on)
622 {
623 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
624 
625 	switch (rq->type) {
626 	case PTP_CLK_REQ_PEROUT:
627 		return icss_iep_perout_enable(iep, &rq->perout, on);
628 	case PTP_CLK_REQ_PPS:
629 		return icss_iep_pps_enable(iep, on);
630 	case PTP_CLK_REQ_EXTTS:
631 		return icss_iep_extts_enable(iep, rq->extts.index, on);
632 	default:
633 		break;
634 	}
635 
636 	return -EOPNOTSUPP;
637 }
638 
639 static struct ptp_clock_info icss_iep_ptp_info = {
640 	.owner		= THIS_MODULE,
641 	.name		= "ICSS IEP timer",
642 	.max_adj	= 10000000,
643 	.adjfine	= icss_iep_ptp_adjfine,
644 	.adjtime	= icss_iep_ptp_adjtime,
645 	.gettimex64	= icss_iep_ptp_gettimeex,
646 	.settime64	= icss_iep_ptp_settime,
647 	.enable		= icss_iep_ptp_enable,
648 };
649 
650 struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx)
651 {
652 	struct platform_device *pdev;
653 	struct device_node *iep_np;
654 	struct icss_iep *iep;
655 
656 	iep_np = of_parse_phandle(np, "ti,iep", idx);
657 	if (!iep_np || !of_device_is_available(iep_np))
658 		return ERR_PTR(-ENODEV);
659 
660 	pdev = of_find_device_by_node(iep_np);
661 	of_node_put(iep_np);
662 
663 	if (!pdev)
664 		/* probably IEP not yet probed */
665 		return ERR_PTR(-EPROBE_DEFER);
666 
667 	iep = platform_get_drvdata(pdev);
668 	if (!iep)
669 		return ERR_PTR(-EPROBE_DEFER);
670 
671 	device_lock(iep->dev);
672 	if (iep->client_np) {
673 		device_unlock(iep->dev);
674 		dev_err(iep->dev, "IEP is already acquired by %s",
675 			iep->client_np->name);
676 		return ERR_PTR(-EBUSY);
677 	}
678 	iep->client_np = np;
679 	device_unlock(iep->dev);
680 	get_device(iep->dev);
681 
682 	return iep;
683 }
684 EXPORT_SYMBOL_GPL(icss_iep_get_idx);
685 
686 struct icss_iep *icss_iep_get(struct device_node *np)
687 {
688 	return icss_iep_get_idx(np, 0);
689 }
690 EXPORT_SYMBOL_GPL(icss_iep_get);
691 
692 void icss_iep_put(struct icss_iep *iep)
693 {
694 	device_lock(iep->dev);
695 	iep->client_np = NULL;
696 	device_unlock(iep->dev);
697 	put_device(iep->dev);
698 }
699 EXPORT_SYMBOL_GPL(icss_iep_put);
700 
701 void icss_iep_init_fw(struct icss_iep *iep)
702 {
703 	/* start IEP for FW use in raw 64bit mode, no PTP support */
704 	iep->clk_tick_time = iep->def_inc;
705 	iep->cycle_time_ns = 0;
706 	iep->ops = NULL;
707 	iep->clockops_data = NULL;
708 	icss_iep_set_default_inc(iep, iep->def_inc);
709 	icss_iep_set_compensation_inc(iep, iep->def_inc);
710 	icss_iep_set_compensation_count(iep, 0);
711 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
712 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
713 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
714 		icss_iep_set_slow_compensation_count(iep, 0);
715 
716 	icss_iep_enable(iep);
717 	icss_iep_settime(iep, 0);
718 }
719 EXPORT_SYMBOL_GPL(icss_iep_init_fw);
720 
721 void icss_iep_exit_fw(struct icss_iep *iep)
722 {
723 	icss_iep_disable(iep);
724 }
725 EXPORT_SYMBOL_GPL(icss_iep_exit_fw);
726 
727 int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
728 		  void *clockops_data, u32 cycle_time_ns)
729 {
730 	int ret = 0;
731 
732 	iep->cycle_time_ns = cycle_time_ns;
733 	iep->clk_tick_time = iep->def_inc;
734 	iep->ops = clkops;
735 	iep->clockops_data = clockops_data;
736 	icss_iep_set_default_inc(iep, iep->def_inc);
737 	icss_iep_set_compensation_inc(iep, iep->def_inc);
738 	icss_iep_set_compensation_count(iep, 0);
739 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
740 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
741 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
742 		icss_iep_set_slow_compensation_count(iep, 0);
743 
744 	if (!(iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) ||
745 	    !(iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT))
746 		goto skip_perout;
747 
748 	if (iep->ops && iep->ops->perout_enable) {
749 		iep->ptp_info.n_per_out = 1;
750 		iep->ptp_info.pps = 1;
751 	}
752 
753 	if (iep->ops && iep->ops->extts_enable)
754 		iep->ptp_info.n_ext_ts = 2;
755 
756 skip_perout:
757 	if (cycle_time_ns)
758 		icss_iep_enable_shadow_mode(iep);
759 	else
760 		icss_iep_enable(iep);
761 	icss_iep_settime(iep, ktime_get_real_ns());
762 
763 	iep->ptp_clock = ptp_clock_register(&iep->ptp_info, iep->dev);
764 	if (IS_ERR(iep->ptp_clock)) {
765 		ret = PTR_ERR(iep->ptp_clock);
766 		iep->ptp_clock = NULL;
767 		dev_err(iep->dev, "Failed to register ptp clk %d\n", ret);
768 	}
769 
770 	return ret;
771 }
772 EXPORT_SYMBOL_GPL(icss_iep_init);
773 
774 int icss_iep_exit(struct icss_iep *iep)
775 {
776 	if (iep->ptp_clock) {
777 		ptp_clock_unregister(iep->ptp_clock);
778 		iep->ptp_clock = NULL;
779 	}
780 	icss_iep_disable(iep);
781 
782 	if (iep->pps_enabled)
783 		icss_iep_pps_enable(iep, false);
784 	else if (iep->perout_enabled)
785 		icss_iep_perout_enable(iep, NULL, false);
786 
787 	return 0;
788 }
789 EXPORT_SYMBOL_GPL(icss_iep_exit);
790 
791 static int icss_iep_probe(struct platform_device *pdev)
792 {
793 	struct device *dev = &pdev->dev;
794 	struct icss_iep *iep;
795 	struct clk *iep_clk;
796 
797 	iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
798 	if (!iep)
799 		return -ENOMEM;
800 
801 	iep->dev = dev;
802 	iep->base = devm_platform_ioremap_resource(pdev, 0);
803 	if (IS_ERR(iep->base))
804 		return -ENODEV;
805 
806 	iep_clk = devm_clk_get(dev, NULL);
807 	if (IS_ERR(iep_clk))
808 		return PTR_ERR(iep_clk);
809 
810 	iep->refclk_freq = clk_get_rate(iep_clk);
811 
812 	iep->def_inc = NSEC_PER_SEC / iep->refclk_freq;	/* ns per clock tick */
813 	if (iep->def_inc > IEP_MAX_DEF_INC) {
814 		dev_err(dev, "Failed to set def_inc %d.  IEP_clock is too slow to be supported\n",
815 			iep->def_inc);
816 		return -EINVAL;
817 	}
818 
819 	iep->plat_data = device_get_match_data(dev);
820 	if (!iep->plat_data)
821 		return -EINVAL;
822 
823 	iep->map = devm_regmap_init(dev, NULL, iep, iep->plat_data->config);
824 	if (IS_ERR(iep->map)) {
825 		dev_err(dev, "Failed to create regmap for IEP %ld\n",
826 			PTR_ERR(iep->map));
827 		return PTR_ERR(iep->map);
828 	}
829 
830 	iep->ptp_info = icss_iep_ptp_info;
831 	mutex_init(&iep->ptp_clk_mutex);
832 	dev_set_drvdata(dev, iep);
833 	icss_iep_disable(iep);
834 
835 	return 0;
836 }
837 
838 static bool am654_icss_iep_valid_reg(struct device *dev, unsigned int reg)
839 {
840 	switch (reg) {
841 	case ICSS_IEP_GLOBAL_CFG_REG ... ICSS_IEP_SYNC_START_REG:
842 		return true;
843 	default:
844 		return false;
845 	}
846 
847 	return false;
848 }
849 
850 static int icss_iep_regmap_write(void *context, unsigned int reg,
851 				 unsigned int val)
852 {
853 	struct icss_iep *iep = context;
854 
855 	writel(val, iep->base + iep->plat_data->reg_offs[reg]);
856 
857 	return 0;
858 }
859 
860 static int icss_iep_regmap_read(void *context, unsigned int reg,
861 				unsigned int *val)
862 {
863 	struct icss_iep *iep = context;
864 
865 	*val = readl(iep->base + iep->plat_data->reg_offs[reg]);
866 
867 	return 0;
868 }
869 
870 static struct regmap_config am654_icss_iep_regmap_config = {
871 	.name = "icss iep",
872 	.reg_stride = 1,
873 	.reg_write = icss_iep_regmap_write,
874 	.reg_read = icss_iep_regmap_read,
875 	.writeable_reg = am654_icss_iep_valid_reg,
876 	.readable_reg = am654_icss_iep_valid_reg,
877 	.fast_io = 1,
878 };
879 
880 static const struct icss_iep_plat_data am654_icss_iep_plat_data = {
881 	.flags = ICSS_IEP_64BIT_COUNTER_SUPPORT |
882 		 ICSS_IEP_SLOW_COMPEN_REG_SUPPORT |
883 		 ICSS_IEP_SHADOW_MODE_SUPPORT,
884 	.reg_offs = {
885 		[ICSS_IEP_GLOBAL_CFG_REG] = 0x00,
886 		[ICSS_IEP_COMPEN_REG] = 0x08,
887 		[ICSS_IEP_SLOW_COMPEN_REG] = 0x0C,
888 		[ICSS_IEP_COUNT_REG0] = 0x10,
889 		[ICSS_IEP_COUNT_REG1] = 0x14,
890 		[ICSS_IEP_CAPTURE_CFG_REG] = 0x18,
891 		[ICSS_IEP_CAPTURE_STAT_REG] = 0x1c,
892 
893 		[ICSS_IEP_CAP6_RISE_REG0] = 0x50,
894 		[ICSS_IEP_CAP6_RISE_REG1] = 0x54,
895 
896 		[ICSS_IEP_CAP7_RISE_REG0] = 0x60,
897 		[ICSS_IEP_CAP7_RISE_REG1] = 0x64,
898 
899 		[ICSS_IEP_CMP_CFG_REG] = 0x70,
900 		[ICSS_IEP_CMP_STAT_REG] = 0x74,
901 		[ICSS_IEP_CMP0_REG0] = 0x78,
902 		[ICSS_IEP_CMP0_REG1] = 0x7c,
903 		[ICSS_IEP_CMP1_REG0] = 0x80,
904 		[ICSS_IEP_CMP1_REG1] = 0x84,
905 
906 		[ICSS_IEP_CMP8_REG0] = 0xc0,
907 		[ICSS_IEP_CMP8_REG1] = 0xc4,
908 		[ICSS_IEP_SYNC_CTRL_REG] = 0x180,
909 		[ICSS_IEP_SYNC0_STAT_REG] = 0x188,
910 		[ICSS_IEP_SYNC1_STAT_REG] = 0x18c,
911 		[ICSS_IEP_SYNC_PWIDTH_REG] = 0x190,
912 		[ICSS_IEP_SYNC0_PERIOD_REG] = 0x194,
913 		[ICSS_IEP_SYNC1_DELAY_REG] = 0x198,
914 		[ICSS_IEP_SYNC_START_REG] = 0x19c,
915 	},
916 	.config = &am654_icss_iep_regmap_config,
917 };
918 
919 static const struct of_device_id icss_iep_of_match[] = {
920 	{
921 		.compatible = "ti,am654-icss-iep",
922 		.data = &am654_icss_iep_plat_data,
923 	},
924 	{},
925 };
926 MODULE_DEVICE_TABLE(of, icss_iep_of_match);
927 
928 static struct platform_driver icss_iep_driver = {
929 	.driver = {
930 		.name = "icss-iep",
931 		.of_match_table = icss_iep_of_match,
932 	},
933 	.probe = icss_iep_probe,
934 };
935 module_platform_driver(icss_iep_driver);
936 
937 MODULE_LICENSE("GPL");
938 MODULE_DESCRIPTION("TI ICSS IEP driver");
939 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
940 MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
941