xref: /linux/drivers/net/ethernet/ti/icssg/icss_iep.c (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
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  */
icss_iep_get_count_hi(struct icss_iep * iep)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  */
icss_iep_get_count_low(struct icss_iep * iep)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  */
icss_iep_get_ptp_clock_idx(struct icss_iep * iep)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 
icss_iep_set_counter(struct icss_iep * iep,u64 ns)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  */
icss_iep_settime(struct icss_iep * iep,u64 ns)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  */
icss_iep_gettime(struct icss_iep * iep,struct ptp_system_timestamp * sts)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 
icss_iep_enable(struct icss_iep * iep)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 
icss_iep_disable(struct icss_iep * iep)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 
icss_iep_enable_shadow_mode(struct icss_iep * iep)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 		regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
220 				   IEP_CMP_CFG_CMP_EN(cmp), 0);
221 	}
222 
223 	/* enable reset counter on CMP0 event */
224 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
225 			   IEP_CMP_CFG_CMP0_RST_CNT_EN,
226 			   IEP_CMP_CFG_CMP0_RST_CNT_EN);
227 	/* enable compare */
228 	regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
229 			   IEP_CMP_CFG_CMP_EN(0),
230 			   IEP_CMP_CFG_CMP_EN(0));
231 
232 	/* set CMP0 value to cycle time */
233 	regmap_write(iep->map, ICSS_IEP_CMP0_REG0, cycle_time);
234 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
235 		regmap_write(iep->map, ICSS_IEP_CMP0_REG1, cycle_time);
236 
237 	icss_iep_set_counter(iep, 0);
238 	icss_iep_enable(iep);
239 }
240 
icss_iep_set_default_inc(struct icss_iep * iep,u8 def_inc)241 static void icss_iep_set_default_inc(struct icss_iep *iep, u8 def_inc)
242 {
243 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
244 			   IEP_GLOBAL_CFG_DEFAULT_INC_MASK,
245 			   def_inc << IEP_GLOBAL_CFG_DEFAULT_INC_SHIFT);
246 }
247 
icss_iep_set_compensation_inc(struct icss_iep * iep,u16 compen_inc)248 static void icss_iep_set_compensation_inc(struct icss_iep *iep, u16 compen_inc)
249 {
250 	struct device *dev = regmap_get_device(iep->map);
251 
252 	if (compen_inc > IEP_MAX_COMPEN_INC) {
253 		dev_err(dev, "%s: too high compensation inc %d\n",
254 			__func__, compen_inc);
255 		compen_inc = IEP_MAX_COMPEN_INC;
256 	}
257 
258 	regmap_update_bits(iep->map, ICSS_IEP_GLOBAL_CFG_REG,
259 			   IEP_GLOBAL_CFG_COMPEN_INC_MASK,
260 			   compen_inc << IEP_GLOBAL_CFG_COMPEN_INC_SHIFT);
261 }
262 
icss_iep_set_compensation_count(struct icss_iep * iep,u32 compen_count)263 static void icss_iep_set_compensation_count(struct icss_iep *iep,
264 					    u32 compen_count)
265 {
266 	struct device *dev = regmap_get_device(iep->map);
267 
268 	if (compen_count > IEP_MAX_COMPEN_COUNT) {
269 		dev_err(dev, "%s: too high compensation count %d\n",
270 			__func__, compen_count);
271 		compen_count = IEP_MAX_COMPEN_COUNT;
272 	}
273 
274 	regmap_write(iep->map, ICSS_IEP_COMPEN_REG, compen_count);
275 }
276 
icss_iep_set_slow_compensation_count(struct icss_iep * iep,u32 compen_count)277 static void icss_iep_set_slow_compensation_count(struct icss_iep *iep,
278 						 u32 compen_count)
279 {
280 	regmap_write(iep->map, ICSS_IEP_SLOW_COMPEN_REG, compen_count);
281 }
282 
283 /* PTP PHC operations */
icss_iep_ptp_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)284 static int icss_iep_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
285 {
286 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
287 	s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
288 	u32 cyc_count;
289 	u16 cmp_inc;
290 
291 	mutex_lock(&iep->ptp_clk_mutex);
292 
293 	/* ppb is amount of frequency we want to adjust in 1GHz (billion)
294 	 * e.g. 100ppb means we need to speed up clock by 100Hz
295 	 * i.e. at end of 1 second (1 billion ns) clock time, we should be
296 	 * counting 100 more ns.
297 	 * We use IEP slow compensation to achieve continuous freq. adjustment.
298 	 * There are 2 parts. Cycle time and adjustment per cycle.
299 	 * Simplest case would be 1 sec Cycle time. Then adjustment
300 	 * pre cycle would be (def_inc + ppb) value.
301 	 * Cycle time will have to be chosen based on how worse the ppb is.
302 	 * e.g. smaller the ppb, cycle time has to be large.
303 	 * The minimum adjustment we can do is +-1ns per cycle so let's
304 	 * reduce the cycle time to get 1ns per cycle adjustment.
305 	 *	1ppb = 1sec cycle time & 1ns adjust
306 	 *	1000ppb = 1/1000 cycle time & 1ns adjust per cycle
307 	 */
308 
309 	if (iep->cycle_time_ns)
310 		iep->slow_cmp_inc = iep->clk_tick_time;	/* 4ns adj per cycle */
311 	else
312 		iep->slow_cmp_inc = 1;	/* 1ns adjust per cycle */
313 
314 	if (ppb < 0) {
315 		iep->slow_cmp_inc = -iep->slow_cmp_inc;
316 		ppb = -ppb;
317 	}
318 
319 	cyc_count = NSEC_PER_SEC;		/* 1s cycle time @1GHz */
320 	cyc_count /= ppb;		/* cycle time per ppb */
321 
322 	/* slow_cmp_count is decremented every clock cycle, e.g. @250MHz */
323 	if (!iep->cycle_time_ns)
324 		cyc_count /= iep->clk_tick_time;
325 	iep->slow_cmp_count = cyc_count;
326 
327 	/* iep->clk_tick_time is def_inc */
328 	cmp_inc = iep->clk_tick_time + iep->slow_cmp_inc;
329 	icss_iep_set_compensation_inc(iep, cmp_inc);
330 	icss_iep_set_slow_compensation_count(iep, iep->slow_cmp_count);
331 
332 	mutex_unlock(&iep->ptp_clk_mutex);
333 
334 	return 0;
335 }
336 
icss_iep_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)337 static int icss_iep_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
338 {
339 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
340 	s64 ns;
341 
342 	mutex_lock(&iep->ptp_clk_mutex);
343 	if (iep->ops && iep->ops->adjtime) {
344 		iep->ops->adjtime(iep->clockops_data, delta);
345 	} else {
346 		ns = icss_iep_gettime(iep, NULL);
347 		ns += delta;
348 		icss_iep_settime(iep, ns);
349 	}
350 	mutex_unlock(&iep->ptp_clk_mutex);
351 
352 	return 0;
353 }
354 
icss_iep_ptp_gettimeex(struct ptp_clock_info * ptp,struct timespec64 * ts,struct ptp_system_timestamp * sts)355 static int icss_iep_ptp_gettimeex(struct ptp_clock_info *ptp,
356 				  struct timespec64 *ts,
357 				  struct ptp_system_timestamp *sts)
358 {
359 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
360 	u64 ns;
361 
362 	mutex_lock(&iep->ptp_clk_mutex);
363 	ns = icss_iep_gettime(iep, sts);
364 	*ts = ns_to_timespec64(ns);
365 	mutex_unlock(&iep->ptp_clk_mutex);
366 
367 	return 0;
368 }
369 
icss_iep_ptp_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)370 static int icss_iep_ptp_settime(struct ptp_clock_info *ptp,
371 				const struct timespec64 *ts)
372 {
373 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
374 	u64 ns;
375 
376 	mutex_lock(&iep->ptp_clk_mutex);
377 	ns = timespec64_to_ns(ts);
378 	icss_iep_settime(iep, ns);
379 	mutex_unlock(&iep->ptp_clk_mutex);
380 
381 	return 0;
382 }
383 
icss_iep_update_to_next_boundary(struct icss_iep * iep,u64 start_ns)384 static void icss_iep_update_to_next_boundary(struct icss_iep *iep, u64 start_ns)
385 {
386 	u64 ns, p_ns;
387 	u32 offset;
388 
389 	ns = icss_iep_gettime(iep, NULL);
390 	if (start_ns < ns)
391 		start_ns = ns;
392 	p_ns = iep->period;
393 	/* Round up to next period boundary */
394 	start_ns += p_ns - 1;
395 	offset = do_div(start_ns, p_ns);
396 	start_ns = start_ns * p_ns;
397 	/* If it is too close to update, shift to next boundary */
398 	if (p_ns - offset < 10)
399 		start_ns += p_ns;
400 
401 	regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(start_ns));
402 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
403 		regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(start_ns));
404 }
405 
icss_iep_perout_enable_hw(struct icss_iep * iep,struct ptp_perout_request * req,int on)406 static int icss_iep_perout_enable_hw(struct icss_iep *iep,
407 				     struct ptp_perout_request *req, int on)
408 {
409 	struct timespec64 ts;
410 	u64 ns_start;
411 	u64 ns_width;
412 	int ret;
413 	u64 cmp;
414 
415 	/* Calculate width of the signal for PPS/PEROUT handling */
416 	ts.tv_sec = req->on.sec;
417 	ts.tv_nsec = req->on.nsec;
418 	ns_width = timespec64_to_ns(&ts);
419 
420 	if (req->flags & PTP_PEROUT_PHASE) {
421 		ts.tv_sec = req->phase.sec;
422 		ts.tv_nsec = req->phase.nsec;
423 		ns_start = timespec64_to_ns(&ts);
424 	} else {
425 		ns_start = 0;
426 	}
427 
428 	if (iep->ops && iep->ops->perout_enable) {
429 		ret = iep->ops->perout_enable(iep->clockops_data, req, on, &cmp);
430 		if (ret)
431 			return ret;
432 
433 		if (on) {
434 			/* Configure CMP */
435 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, lower_32_bits(cmp));
436 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
437 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, upper_32_bits(cmp));
438 			/* Configure SYNC, based on req on width */
439 			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
440 				     div_u64(ns_width, iep->def_inc));
441 			regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
442 			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
443 				     div_u64(ns_start, iep->def_inc));
444 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0); /* one-shot mode */
445 			/* Enable CMP 1 */
446 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
447 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
448 		} else {
449 			/* Disable CMP 1 */
450 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
451 					   IEP_CMP_CFG_CMP_EN(1), 0);
452 
453 			/* clear regs */
454 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
455 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
456 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
457 		}
458 	} else {
459 		if (on) {
460 			u64 start_ns;
461 
462 			iep->period = ((u64)req->period.sec * NSEC_PER_SEC) +
463 				      req->period.nsec;
464 			start_ns = ((u64)req->period.sec * NSEC_PER_SEC)
465 				   + req->period.nsec;
466 			icss_iep_update_to_next_boundary(iep, start_ns);
467 
468 			regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG,
469 				     div_u64(ns_width, iep->def_inc));
470 			regmap_write(iep->map, ICSS_IEP_SYNC_START_REG,
471 				     div_u64(ns_start, iep->def_inc));
472 			/* Enable Sync in single shot mode  */
473 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG,
474 				     IEP_SYNC_CTRL_SYNC_N_EN(0) | IEP_SYNC_CTRL_SYNC_EN);
475 			/* Enable CMP 1 */
476 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
477 					   IEP_CMP_CFG_CMP_EN(1), IEP_CMP_CFG_CMP_EN(1));
478 		} else {
479 			/* Disable CMP 1 */
480 			regmap_update_bits(iep->map, ICSS_IEP_CMP_CFG_REG,
481 					   IEP_CMP_CFG_CMP_EN(1), 0);
482 
483 			/* clear CMP regs */
484 			regmap_write(iep->map, ICSS_IEP_CMP1_REG0, 0);
485 			if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
486 				regmap_write(iep->map, ICSS_IEP_CMP1_REG1, 0);
487 
488 			/* Disable sync */
489 			regmap_write(iep->map, ICSS_IEP_SYNC_CTRL_REG, 0);
490 		}
491 	}
492 
493 	return 0;
494 }
495 
icss_iep_perout_enable(struct icss_iep * iep,struct ptp_perout_request * req,int on)496 static int icss_iep_perout_enable(struct icss_iep *iep,
497 				  struct ptp_perout_request *req, int on)
498 {
499 	int ret = 0;
500 
501 	/* Reject requests with unsupported flags */
502 	if (req->flags & ~(PTP_PEROUT_DUTY_CYCLE |
503 			  PTP_PEROUT_PHASE))
504 		return -EOPNOTSUPP;
505 
506 	mutex_lock(&iep->ptp_clk_mutex);
507 
508 	if (iep->pps_enabled) {
509 		ret = -EBUSY;
510 		goto exit;
511 	}
512 
513 	if (iep->perout_enabled == !!on)
514 		goto exit;
515 
516 	/* Set default "on" time (1ms) for the signal if not passed by the app */
517 	if (!(req->flags & PTP_PEROUT_DUTY_CYCLE)) {
518 		req->on.sec = 0;
519 		req->on.nsec = NSEC_PER_MSEC;
520 	}
521 
522 	ret = icss_iep_perout_enable_hw(iep, req, on);
523 	if (!ret)
524 		iep->perout_enabled = !!on;
525 
526 exit:
527 	mutex_unlock(&iep->ptp_clk_mutex);
528 
529 	return ret;
530 }
531 
icss_iep_cap_cmp_work(struct work_struct * work)532 static void icss_iep_cap_cmp_work(struct work_struct *work)
533 {
534 	struct icss_iep *iep = container_of(work, struct icss_iep, work);
535 	const u32 *reg_offs = iep->plat_data->reg_offs;
536 	struct ptp_clock_event pevent;
537 	unsigned int val;
538 	u64 ns, ns_next;
539 
540 	mutex_lock(&iep->ptp_clk_mutex);
541 
542 	ns = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
543 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) {
544 		val = readl(iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
545 		ns |= (u64)val << 32;
546 	}
547 	/* set next event */
548 	ns_next = ns + iep->period;
549 	writel(lower_32_bits(ns_next),
550 	       iep->base + reg_offs[ICSS_IEP_CMP1_REG0]);
551 	if (iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT)
552 		writel(upper_32_bits(ns_next),
553 		       iep->base + reg_offs[ICSS_IEP_CMP1_REG1]);
554 
555 	pevent.pps_times.ts_real = ns_to_timespec64(ns);
556 	pevent.type = PTP_CLOCK_PPSUSR;
557 	pevent.index = 0;
558 	ptp_clock_event(iep->ptp_clock, &pevent);
559 	dev_dbg(iep->dev, "IEP:pps ts: %llu next:%llu:\n", ns, ns_next);
560 
561 	mutex_unlock(&iep->ptp_clk_mutex);
562 }
563 
icss_iep_cap_cmp_irq(int irq,void * dev_id)564 static irqreturn_t icss_iep_cap_cmp_irq(int irq, void *dev_id)
565 {
566 	struct icss_iep *iep = (struct icss_iep *)dev_id;
567 	const u32 *reg_offs = iep->plat_data->reg_offs;
568 	unsigned int val;
569 
570 	val = readl(iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
571 	/* The driver only enables CMP1 */
572 	if (val & BIT(1)) {
573 		/* Clear the event */
574 		writel(BIT(1), iep->base + reg_offs[ICSS_IEP_CMP_STAT_REG]);
575 		if (iep->pps_enabled || iep->perout_enabled)
576 			schedule_work(&iep->work);
577 		return IRQ_HANDLED;
578 	}
579 
580 	return IRQ_NONE;
581 }
582 
icss_iep_pps_enable(struct icss_iep * iep,int on)583 static int icss_iep_pps_enable(struct icss_iep *iep, int on)
584 {
585 	struct ptp_clock_request rq;
586 	struct timespec64 ts;
587 	int ret = 0;
588 	u64 ns;
589 
590 	mutex_lock(&iep->ptp_clk_mutex);
591 
592 	if (iep->perout_enabled) {
593 		ret = -EBUSY;
594 		goto exit;
595 	}
596 
597 	if (iep->pps_enabled == !!on)
598 		goto exit;
599 
600 	rq.perout.index = 0;
601 	if (on) {
602 		ns = icss_iep_gettime(iep, NULL);
603 		ts = ns_to_timespec64(ns);
604 		rq.perout.flags = 0;
605 		rq.perout.period.sec = 1;
606 		rq.perout.period.nsec = 0;
607 		rq.perout.start.sec = ts.tv_sec + 2;
608 		rq.perout.start.nsec = 0;
609 		rq.perout.on.sec = 0;
610 		rq.perout.on.nsec = NSEC_PER_MSEC;
611 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
612 	} else {
613 		ret = icss_iep_perout_enable_hw(iep, &rq.perout, on);
614 		if (iep->cap_cmp_irq)
615 			cancel_work_sync(&iep->work);
616 	}
617 
618 	if (!ret)
619 		iep->pps_enabled = !!on;
620 
621 exit:
622 	mutex_unlock(&iep->ptp_clk_mutex);
623 
624 	return ret;
625 }
626 
icss_iep_extts_enable(struct icss_iep * iep,u32 index,int on)627 static int icss_iep_extts_enable(struct icss_iep *iep, u32 index, int on)
628 {
629 	u32 val, cap, ret = 0;
630 
631 	mutex_lock(&iep->ptp_clk_mutex);
632 
633 	if (iep->ops && iep->ops->extts_enable) {
634 		ret = iep->ops->extts_enable(iep->clockops_data, index, on);
635 		goto exit;
636 	}
637 
638 	if (((iep->latch_enable & BIT(index)) >> index) == on)
639 		goto exit;
640 
641 	regmap_read(iep->map, ICSS_IEP_CAPTURE_CFG_REG, &val);
642 	cap = IEP_CAP_CFG_CAP_ASYNC_EN(index) | IEP_CAP_CFG_CAPNR_1ST_EVENT_EN(index);
643 	if (on) {
644 		val |= cap;
645 		iep->latch_enable |= BIT(index);
646 	} else {
647 		val &= ~cap;
648 		iep->latch_enable &= ~BIT(index);
649 	}
650 	regmap_write(iep->map, ICSS_IEP_CAPTURE_CFG_REG, val);
651 
652 exit:
653 	mutex_unlock(&iep->ptp_clk_mutex);
654 
655 	return ret;
656 }
657 
icss_iep_ptp_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)658 static int icss_iep_ptp_enable(struct ptp_clock_info *ptp,
659 			       struct ptp_clock_request *rq, int on)
660 {
661 	struct icss_iep *iep = container_of(ptp, struct icss_iep, ptp_info);
662 
663 	switch (rq->type) {
664 	case PTP_CLK_REQ_PEROUT:
665 		return icss_iep_perout_enable(iep, &rq->perout, on);
666 	case PTP_CLK_REQ_PPS:
667 		return icss_iep_pps_enable(iep, on);
668 	case PTP_CLK_REQ_EXTTS:
669 		return icss_iep_extts_enable(iep, rq->extts.index, on);
670 	default:
671 		break;
672 	}
673 
674 	return -EOPNOTSUPP;
675 }
676 
677 static struct ptp_clock_info icss_iep_ptp_info = {
678 	.owner		= THIS_MODULE,
679 	.name		= "ICSS IEP timer",
680 	.max_adj	= 10000000,
681 	.adjfine	= icss_iep_ptp_adjfine,
682 	.adjtime	= icss_iep_ptp_adjtime,
683 	.gettimex64	= icss_iep_ptp_gettimeex,
684 	.settime64	= icss_iep_ptp_settime,
685 	.enable		= icss_iep_ptp_enable,
686 };
687 
icss_iep_get_idx(struct device_node * np,int idx)688 struct icss_iep *icss_iep_get_idx(struct device_node *np, int idx)
689 {
690 	struct platform_device *pdev;
691 	struct device_node *iep_np;
692 	struct icss_iep *iep;
693 
694 	iep_np = of_parse_phandle(np, "ti,iep", idx);
695 	if (!iep_np || !of_device_is_available(iep_np))
696 		return ERR_PTR(-ENODEV);
697 
698 	pdev = of_find_device_by_node(iep_np);
699 	of_node_put(iep_np);
700 
701 	if (!pdev)
702 		/* probably IEP not yet probed */
703 		return ERR_PTR(-EPROBE_DEFER);
704 
705 	iep = platform_get_drvdata(pdev);
706 	if (!iep)
707 		return ERR_PTR(-EPROBE_DEFER);
708 
709 	device_lock(iep->dev);
710 	if (iep->client_np) {
711 		device_unlock(iep->dev);
712 		dev_err(iep->dev, "IEP is already acquired by %s",
713 			iep->client_np->name);
714 		return ERR_PTR(-EBUSY);
715 	}
716 	iep->client_np = np;
717 	device_unlock(iep->dev);
718 	get_device(iep->dev);
719 
720 	return iep;
721 }
722 EXPORT_SYMBOL_GPL(icss_iep_get_idx);
723 
icss_iep_get(struct device_node * np)724 struct icss_iep *icss_iep_get(struct device_node *np)
725 {
726 	return icss_iep_get_idx(np, 0);
727 }
728 EXPORT_SYMBOL_GPL(icss_iep_get);
729 
icss_iep_put(struct icss_iep * iep)730 void icss_iep_put(struct icss_iep *iep)
731 {
732 	device_lock(iep->dev);
733 	iep->client_np = NULL;
734 	device_unlock(iep->dev);
735 	put_device(iep->dev);
736 }
737 EXPORT_SYMBOL_GPL(icss_iep_put);
738 
icss_iep_init_fw(struct icss_iep * iep)739 void icss_iep_init_fw(struct icss_iep *iep)
740 {
741 	/* start IEP for FW use in raw 64bit mode, no PTP support */
742 	iep->clk_tick_time = iep->def_inc;
743 	iep->cycle_time_ns = 0;
744 	iep->ops = NULL;
745 	iep->clockops_data = NULL;
746 	icss_iep_set_default_inc(iep, iep->def_inc);
747 	icss_iep_set_compensation_inc(iep, iep->def_inc);
748 	icss_iep_set_compensation_count(iep, 0);
749 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
750 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
751 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
752 		icss_iep_set_slow_compensation_count(iep, 0);
753 
754 	icss_iep_enable(iep);
755 	icss_iep_settime(iep, 0);
756 }
757 EXPORT_SYMBOL_GPL(icss_iep_init_fw);
758 
icss_iep_exit_fw(struct icss_iep * iep)759 void icss_iep_exit_fw(struct icss_iep *iep)
760 {
761 	icss_iep_disable(iep);
762 }
763 EXPORT_SYMBOL_GPL(icss_iep_exit_fw);
764 
icss_iep_init(struct icss_iep * iep,const struct icss_iep_clockops * clkops,void * clockops_data,u32 cycle_time_ns)765 int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
766 		  void *clockops_data, u32 cycle_time_ns)
767 {
768 	int ret = 0;
769 
770 	iep->cycle_time_ns = cycle_time_ns;
771 	iep->clk_tick_time = iep->def_inc;
772 	iep->ops = clkops;
773 	iep->clockops_data = clockops_data;
774 	icss_iep_set_default_inc(iep, iep->def_inc);
775 	icss_iep_set_compensation_inc(iep, iep->def_inc);
776 	icss_iep_set_compensation_count(iep, 0);
777 	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
778 	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
779 	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
780 		icss_iep_set_slow_compensation_count(iep, 0);
781 
782 	if (!(iep->plat_data->flags & ICSS_IEP_64BIT_COUNTER_SUPPORT) ||
783 	    !(iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT))
784 		goto skip_perout;
785 
786 	if (iep->ops && iep->ops->perout_enable) {
787 		iep->ptp_info.n_per_out = 1;
788 		iep->ptp_info.pps = 1;
789 	} else if (iep->cap_cmp_irq) {
790 		iep->ptp_info.pps = 1;
791 	}
792 
793 	if (iep->ops && iep->ops->extts_enable)
794 		iep->ptp_info.n_ext_ts = 2;
795 
796 skip_perout:
797 	if (cycle_time_ns)
798 		icss_iep_enable_shadow_mode(iep);
799 	else
800 		icss_iep_enable(iep);
801 	icss_iep_settime(iep, ktime_get_real_ns());
802 
803 	iep->ptp_clock = ptp_clock_register(&iep->ptp_info, iep->dev);
804 	if (IS_ERR(iep->ptp_clock)) {
805 		ret = PTR_ERR(iep->ptp_clock);
806 		iep->ptp_clock = NULL;
807 		dev_err(iep->dev, "Failed to register ptp clk %d\n", ret);
808 	}
809 
810 	return ret;
811 }
812 EXPORT_SYMBOL_GPL(icss_iep_init);
813 
icss_iep_exit(struct icss_iep * iep)814 int icss_iep_exit(struct icss_iep *iep)
815 {
816 	if (iep->ptp_clock) {
817 		ptp_clock_unregister(iep->ptp_clock);
818 		iep->ptp_clock = NULL;
819 	}
820 	icss_iep_disable(iep);
821 
822 	if (iep->pps_enabled)
823 		icss_iep_pps_enable(iep, false);
824 	else if (iep->perout_enabled)
825 		icss_iep_perout_enable(iep, NULL, false);
826 
827 	return 0;
828 }
829 EXPORT_SYMBOL_GPL(icss_iep_exit);
830 
icss_iep_probe(struct platform_device * pdev)831 static int icss_iep_probe(struct platform_device *pdev)
832 {
833 	struct device *dev = &pdev->dev;
834 	struct icss_iep *iep;
835 	struct clk *iep_clk;
836 	int ret, irq;
837 
838 	iep = devm_kzalloc(dev, sizeof(*iep), GFP_KERNEL);
839 	if (!iep)
840 		return -ENOMEM;
841 
842 	iep->dev = dev;
843 	iep->base = devm_platform_ioremap_resource(pdev, 0);
844 	if (IS_ERR(iep->base))
845 		return -ENODEV;
846 
847 	irq = platform_get_irq_byname_optional(pdev, "iep_cap_cmp");
848 	if (irq == -EPROBE_DEFER)
849 		return irq;
850 
851 	if (irq > 0) {
852 		ret = devm_request_irq(dev, irq, icss_iep_cap_cmp_irq,
853 				       IRQF_TRIGGER_HIGH, "iep_cap_cmp", iep);
854 		if (ret) {
855 			dev_info(iep->dev, "cap_cmp irq request failed: %x\n",
856 				 ret);
857 		} else {
858 			iep->cap_cmp_irq = irq;
859 			INIT_WORK(&iep->work, icss_iep_cap_cmp_work);
860 		}
861 	}
862 
863 	iep_clk = devm_clk_get(dev, NULL);
864 	if (IS_ERR(iep_clk))
865 		return PTR_ERR(iep_clk);
866 
867 	iep->refclk_freq = clk_get_rate(iep_clk);
868 
869 	iep->def_inc = NSEC_PER_SEC / iep->refclk_freq;	/* ns per clock tick */
870 	if (iep->def_inc > IEP_MAX_DEF_INC) {
871 		dev_err(dev, "Failed to set def_inc %d.  IEP_clock is too slow to be supported\n",
872 			iep->def_inc);
873 		return -EINVAL;
874 	}
875 
876 	iep->plat_data = device_get_match_data(dev);
877 	if (!iep->plat_data)
878 		return -EINVAL;
879 
880 	iep->map = devm_regmap_init(dev, NULL, iep, iep->plat_data->config);
881 	if (IS_ERR(iep->map)) {
882 		dev_err(dev, "Failed to create regmap for IEP %ld\n",
883 			PTR_ERR(iep->map));
884 		return PTR_ERR(iep->map);
885 	}
886 
887 	iep->ptp_info = icss_iep_ptp_info;
888 	mutex_init(&iep->ptp_clk_mutex);
889 	dev_set_drvdata(dev, iep);
890 	icss_iep_disable(iep);
891 
892 	return 0;
893 }
894 
am654_icss_iep_valid_reg(struct device * dev,unsigned int reg)895 static bool am654_icss_iep_valid_reg(struct device *dev, unsigned int reg)
896 {
897 	switch (reg) {
898 	case ICSS_IEP_GLOBAL_CFG_REG ... ICSS_IEP_SYNC_START_REG:
899 		return true;
900 	default:
901 		return false;
902 	}
903 
904 	return false;
905 }
906 
icss_iep_regmap_write(void * context,unsigned int reg,unsigned int val)907 static int icss_iep_regmap_write(void *context, unsigned int reg,
908 				 unsigned int val)
909 {
910 	struct icss_iep *iep = context;
911 
912 	writel(val, iep->base + iep->plat_data->reg_offs[reg]);
913 
914 	return 0;
915 }
916 
icss_iep_regmap_read(void * context,unsigned int reg,unsigned int * val)917 static int icss_iep_regmap_read(void *context, unsigned int reg,
918 				unsigned int *val)
919 {
920 	struct icss_iep *iep = context;
921 
922 	*val = readl(iep->base + iep->plat_data->reg_offs[reg]);
923 
924 	return 0;
925 }
926 
927 static const struct regmap_config am654_icss_iep_regmap_config = {
928 	.name = "icss iep",
929 	.reg_stride = 1,
930 	.reg_write = icss_iep_regmap_write,
931 	.reg_read = icss_iep_regmap_read,
932 	.writeable_reg = am654_icss_iep_valid_reg,
933 	.readable_reg = am654_icss_iep_valid_reg,
934 	.fast_io = 1,
935 };
936 
937 static const struct icss_iep_plat_data am654_icss_iep_plat_data = {
938 	.flags = ICSS_IEP_64BIT_COUNTER_SUPPORT |
939 		 ICSS_IEP_SLOW_COMPEN_REG_SUPPORT |
940 		 ICSS_IEP_SHADOW_MODE_SUPPORT,
941 	.reg_offs = {
942 		[ICSS_IEP_GLOBAL_CFG_REG] = 0x00,
943 		[ICSS_IEP_COMPEN_REG] = 0x08,
944 		[ICSS_IEP_SLOW_COMPEN_REG] = 0x0C,
945 		[ICSS_IEP_COUNT_REG0] = 0x10,
946 		[ICSS_IEP_COUNT_REG1] = 0x14,
947 		[ICSS_IEP_CAPTURE_CFG_REG] = 0x18,
948 		[ICSS_IEP_CAPTURE_STAT_REG] = 0x1c,
949 
950 		[ICSS_IEP_CAP6_RISE_REG0] = 0x50,
951 		[ICSS_IEP_CAP6_RISE_REG1] = 0x54,
952 
953 		[ICSS_IEP_CAP7_RISE_REG0] = 0x60,
954 		[ICSS_IEP_CAP7_RISE_REG1] = 0x64,
955 
956 		[ICSS_IEP_CMP_CFG_REG] = 0x70,
957 		[ICSS_IEP_CMP_STAT_REG] = 0x74,
958 		[ICSS_IEP_CMP0_REG0] = 0x78,
959 		[ICSS_IEP_CMP0_REG1] = 0x7c,
960 		[ICSS_IEP_CMP1_REG0] = 0x80,
961 		[ICSS_IEP_CMP1_REG1] = 0x84,
962 
963 		[ICSS_IEP_CMP8_REG0] = 0xc0,
964 		[ICSS_IEP_CMP8_REG1] = 0xc4,
965 		[ICSS_IEP_SYNC_CTRL_REG] = 0x180,
966 		[ICSS_IEP_SYNC0_STAT_REG] = 0x188,
967 		[ICSS_IEP_SYNC1_STAT_REG] = 0x18c,
968 		[ICSS_IEP_SYNC_PWIDTH_REG] = 0x190,
969 		[ICSS_IEP_SYNC0_PERIOD_REG] = 0x194,
970 		[ICSS_IEP_SYNC1_DELAY_REG] = 0x198,
971 		[ICSS_IEP_SYNC_START_REG] = 0x19c,
972 	},
973 	.config = &am654_icss_iep_regmap_config,
974 };
975 
976 static const struct of_device_id icss_iep_of_match[] = {
977 	{
978 		.compatible = "ti,am654-icss-iep",
979 		.data = &am654_icss_iep_plat_data,
980 	},
981 	{},
982 };
983 MODULE_DEVICE_TABLE(of, icss_iep_of_match);
984 
985 static struct platform_driver icss_iep_driver = {
986 	.driver = {
987 		.name = "icss-iep",
988 		.of_match_table = icss_iep_of_match,
989 	},
990 	.probe = icss_iep_probe,
991 };
992 module_platform_driver(icss_iep_driver);
993 
994 MODULE_LICENSE("GPL");
995 MODULE_DESCRIPTION("TI ICSS IEP driver");
996 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
997 MODULE_AUTHOR("Md Danish Anwar <danishanwar@ti.com>");
998