1 /* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
2  *
3  * Description: CoreSight System Trace Macrocell driver
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 and
7  * only version 2 as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * Initial implementation by Pratik Patel
15  * (C) 2014-2015 Pratik Patel <pratikp@codeaurora.org>
16  *
17  * Serious refactoring, code cleanup and upgrading to the Coresight upstream
18  * framework by Mathieu Poirier
19  * (C) 2015-2016 Mathieu Poirier <mathieu.poirier@linaro.org>
20  *
21  * Guaranteed timing and support for various packet type coming from the
22  * generic STM API by Chunyan Zhang
23  * (C) 2015-2016 Chunyan Zhang <zhang.chunyan@linaro.org>
24  */
25 #include <asm/local.h>
26 #include <linux/amba/bus.h>
27 #include <linux/bitmap.h>
28 #include <linux/clk.h>
29 #include <linux/coresight.h>
30 #include <linux/coresight-stm.h>
31 #include <linux/err.h>
32 #include <linux/kernel.h>
33 #include <linux/moduleparam.h>
34 #include <linux/of_address.h>
35 #include <linux/perf_event.h>
36 #include <linux/pm_runtime.h>
37 #include <linux/stm.h>
38 
39 #include "coresight-priv.h"
40 
41 #define STMDMASTARTR			0xc04
42 #define STMDMASTOPR			0xc08
43 #define STMDMASTATR			0xc0c
44 #define STMDMACTLR			0xc10
45 #define STMDMAIDR			0xcfc
46 #define STMHEER				0xd00
47 #define STMHETER			0xd20
48 #define STMHEBSR			0xd60
49 #define STMHEMCR			0xd64
50 #define STMHEMASTR			0xdf4
51 #define STMHEFEAT1R			0xdf8
52 #define STMHEIDR			0xdfc
53 #define STMSPER				0xe00
54 #define STMSPTER			0xe20
55 #define STMPRIVMASKR			0xe40
56 #define STMSPSCR			0xe60
57 #define STMSPMSCR			0xe64
58 #define STMSPOVERRIDER			0xe68
59 #define STMSPMOVERRIDER			0xe6c
60 #define STMSPTRIGCSR			0xe70
61 #define STMTCSR				0xe80
62 #define STMTSSTIMR			0xe84
63 #define STMTSFREQR			0xe8c
64 #define STMSYNCR			0xe90
65 #define STMAUXCR			0xe94
66 #define STMSPFEAT1R			0xea0
67 #define STMSPFEAT2R			0xea4
68 #define STMSPFEAT3R			0xea8
69 #define STMITTRIGGER			0xee8
70 #define STMITATBDATA0			0xeec
71 #define STMITATBCTR2			0xef0
72 #define STMITATBID			0xef4
73 #define STMITATBCTR0			0xef8
74 
75 #define STM_32_CHANNEL			32
76 #define BYTES_PER_CHANNEL		256
77 #define STM_TRACE_BUF_SIZE		4096
78 #define STM_SW_MASTER_END		127
79 
80 /* Register bit definition */
81 #define STMTCSR_BUSY_BIT		23
82 /* Reserve the first 10 channels for kernel usage */
83 #define STM_CHANNEL_OFFSET		0
84 
85 enum stm_pkt_type {
86 	STM_PKT_TYPE_DATA	= 0x98,
87 	STM_PKT_TYPE_FLAG	= 0xE8,
88 	STM_PKT_TYPE_TRIG	= 0xF8,
89 };
90 
91 #define stm_channel_addr(drvdata, ch)	(drvdata->chs.base +	\
92 					(ch * BYTES_PER_CHANNEL))
93 #define stm_channel_off(type, opts)	(type & ~opts)
94 
95 static int boot_nr_channel;
96 
97 /*
98  * Not really modular but using module_param is the easiest way to
99  * remain consistent with existing use cases for now.
100  */
101 module_param_named(
102 	boot_nr_channel, boot_nr_channel, int, S_IRUGO
103 );
104 
105 /**
106  * struct channel_space - central management entity for extended ports
107  * @base:		memory mapped base address where channels start.
108  * @phys:		physical base address of channel region.
109  * @guaraneed:		is the channel delivery guaranteed.
110  */
111 struct channel_space {
112 	void __iomem		*base;
113 	phys_addr_t		phys;
114 	unsigned long		*guaranteed;
115 };
116 
117 /**
118  * struct stm_drvdata - specifics associated to an STM component
119  * @base:		memory mapped base address for this component.
120  * @dev:		the device entity associated to this component.
121  * @atclk:		optional clock for the core parts of the STM.
122  * @csdev:		component vitals needed by the framework.
123  * @spinlock:		only one at a time pls.
124  * @chs:		the channels accociated to this STM.
125  * @stm:		structure associated to the generic STM interface.
126  * @mode:		this tracer's mode, i.e sysFS, or disabled.
127  * @traceid:		value of the current ID for this component.
128  * @write_bytes:	Maximus bytes this STM can write at a time.
129  * @stmsper:		settings for register STMSPER.
130  * @stmspscr:		settings for register STMSPSCR.
131  * @numsp:		the total number of stimulus port support by this STM.
132  * @stmheer:		settings for register STMHEER.
133  * @stmheter:		settings for register STMHETER.
134  * @stmhebsr:		settings for register STMHEBSR.
135  */
136 struct stm_drvdata {
137 	void __iomem		*base;
138 	struct device		*dev;
139 	struct clk		*atclk;
140 	struct coresight_device	*csdev;
141 	spinlock_t		spinlock;
142 	struct channel_space	chs;
143 	struct stm_data		stm;
144 	local_t			mode;
145 	u8			traceid;
146 	u32			write_bytes;
147 	u32			stmsper;
148 	u32			stmspscr;
149 	u32			numsp;
150 	u32			stmheer;
151 	u32			stmheter;
152 	u32			stmhebsr;
153 };
154 
155 static void stm_hwevent_enable_hw(struct stm_drvdata *drvdata)
156 {
157 	CS_UNLOCK(drvdata->base);
158 
159 	writel_relaxed(drvdata->stmhebsr, drvdata->base + STMHEBSR);
160 	writel_relaxed(drvdata->stmheter, drvdata->base + STMHETER);
161 	writel_relaxed(drvdata->stmheer, drvdata->base + STMHEER);
162 	writel_relaxed(0x01 |	/* Enable HW event tracing */
163 		       0x04,	/* Error detection on event tracing */
164 		       drvdata->base + STMHEMCR);
165 
166 	CS_LOCK(drvdata->base);
167 }
168 
169 static void stm_port_enable_hw(struct stm_drvdata *drvdata)
170 {
171 	CS_UNLOCK(drvdata->base);
172 	/* ATB trigger enable on direct writes to TRIG locations */
173 	writel_relaxed(0x10,
174 		       drvdata->base + STMSPTRIGCSR);
175 	writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
176 	writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
177 
178 	CS_LOCK(drvdata->base);
179 }
180 
181 static void stm_enable_hw(struct stm_drvdata *drvdata)
182 {
183 	if (drvdata->stmheer)
184 		stm_hwevent_enable_hw(drvdata);
185 
186 	stm_port_enable_hw(drvdata);
187 
188 	CS_UNLOCK(drvdata->base);
189 
190 	/* 4096 byte between synchronisation packets */
191 	writel_relaxed(0xFFF, drvdata->base + STMSYNCR);
192 	writel_relaxed((drvdata->traceid << 16 | /* trace id */
193 			0x02 |			 /* timestamp enable */
194 			0x01),			 /* global STM enable */
195 			drvdata->base + STMTCSR);
196 
197 	CS_LOCK(drvdata->base);
198 }
199 
200 static int stm_enable(struct coresight_device *csdev,
201 		      struct perf_event *event, u32 mode)
202 {
203 	u32 val;
204 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
205 
206 	if (mode != CS_MODE_SYSFS)
207 		return -EINVAL;
208 
209 	val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode);
210 
211 	/* Someone is already using the tracer */
212 	if (val)
213 		return -EBUSY;
214 
215 	pm_runtime_get_sync(drvdata->dev);
216 
217 	spin_lock(&drvdata->spinlock);
218 	stm_enable_hw(drvdata);
219 	spin_unlock(&drvdata->spinlock);
220 
221 	dev_info(drvdata->dev, "STM tracing enabled\n");
222 	return 0;
223 }
224 
225 static void stm_hwevent_disable_hw(struct stm_drvdata *drvdata)
226 {
227 	CS_UNLOCK(drvdata->base);
228 
229 	writel_relaxed(0x0, drvdata->base + STMHEMCR);
230 	writel_relaxed(0x0, drvdata->base + STMHEER);
231 	writel_relaxed(0x0, drvdata->base + STMHETER);
232 
233 	CS_LOCK(drvdata->base);
234 }
235 
236 static void stm_port_disable_hw(struct stm_drvdata *drvdata)
237 {
238 	CS_UNLOCK(drvdata->base);
239 
240 	writel_relaxed(0x0, drvdata->base + STMSPER);
241 	writel_relaxed(0x0, drvdata->base + STMSPTRIGCSR);
242 
243 	CS_LOCK(drvdata->base);
244 }
245 
246 static void stm_disable_hw(struct stm_drvdata *drvdata)
247 {
248 	u32 val;
249 
250 	CS_UNLOCK(drvdata->base);
251 
252 	val = readl_relaxed(drvdata->base + STMTCSR);
253 	val &= ~0x1; /* clear global STM enable [0] */
254 	writel_relaxed(val, drvdata->base + STMTCSR);
255 
256 	CS_LOCK(drvdata->base);
257 
258 	stm_port_disable_hw(drvdata);
259 	if (drvdata->stmheer)
260 		stm_hwevent_disable_hw(drvdata);
261 }
262 
263 static void stm_disable(struct coresight_device *csdev,
264 			struct perf_event *event)
265 {
266 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
267 
268 	/*
269 	 * For as long as the tracer isn't disabled another entity can't
270 	 * change its status.  As such we can read the status here without
271 	 * fearing it will change under us.
272 	 */
273 	if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
274 		spin_lock(&drvdata->spinlock);
275 		stm_disable_hw(drvdata);
276 		spin_unlock(&drvdata->spinlock);
277 
278 		/* Wait until the engine has completely stopped */
279 		coresight_timeout(drvdata, STMTCSR, STMTCSR_BUSY_BIT, 0);
280 
281 		pm_runtime_put(drvdata->dev);
282 
283 		local_set(&drvdata->mode, CS_MODE_DISABLED);
284 		dev_info(drvdata->dev, "STM tracing disabled\n");
285 	}
286 }
287 
288 static int stm_trace_id(struct coresight_device *csdev)
289 {
290 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
291 
292 	return drvdata->traceid;
293 }
294 
295 static const struct coresight_ops_source stm_source_ops = {
296 	.trace_id	= stm_trace_id,
297 	.enable		= stm_enable,
298 	.disable	= stm_disable,
299 };
300 
301 static const struct coresight_ops stm_cs_ops = {
302 	.source_ops	= &stm_source_ops,
303 };
304 
305 static inline bool stm_addr_unaligned(const void *addr, u8 write_bytes)
306 {
307 	return ((unsigned long)addr & (write_bytes - 1));
308 }
309 
310 static void stm_send(void *addr, const void *data, u32 size, u8 write_bytes)
311 {
312 	u8 paload[8];
313 
314 	if (stm_addr_unaligned(data, write_bytes)) {
315 		memcpy(paload, data, size);
316 		data = paload;
317 	}
318 
319 	/* now we are 64bit/32bit aligned */
320 	switch (size) {
321 #ifdef CONFIG_64BIT
322 	case 8:
323 		writeq_relaxed(*(u64 *)data, addr);
324 		break;
325 #endif
326 	case 4:
327 		writel_relaxed(*(u32 *)data, addr);
328 		break;
329 	case 2:
330 		writew_relaxed(*(u16 *)data, addr);
331 		break;
332 	case 1:
333 		writeb_relaxed(*(u8 *)data, addr);
334 		break;
335 	default:
336 		break;
337 	}
338 }
339 
340 static int stm_generic_link(struct stm_data *stm_data,
341 			    unsigned int master,  unsigned int channel)
342 {
343 	struct stm_drvdata *drvdata = container_of(stm_data,
344 						   struct stm_drvdata, stm);
345 	if (!drvdata || !drvdata->csdev)
346 		return -EINVAL;
347 
348 	return coresight_enable(drvdata->csdev);
349 }
350 
351 static void stm_generic_unlink(struct stm_data *stm_data,
352 			       unsigned int master,  unsigned int channel)
353 {
354 	struct stm_drvdata *drvdata = container_of(stm_data,
355 						   struct stm_drvdata, stm);
356 	if (!drvdata || !drvdata->csdev)
357 		return;
358 
359 	coresight_disable(drvdata->csdev);
360 }
361 
362 static phys_addr_t
363 stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
364 	      unsigned int channel, unsigned int nr_chans)
365 {
366 	struct stm_drvdata *drvdata = container_of(stm_data,
367 						   struct stm_drvdata, stm);
368 	phys_addr_t addr;
369 
370 	addr = drvdata->chs.phys + channel * BYTES_PER_CHANNEL;
371 
372 	if (offset_in_page(addr) ||
373 	    offset_in_page(nr_chans * BYTES_PER_CHANNEL))
374 		return 0;
375 
376 	return addr;
377 }
378 
379 static long stm_generic_set_options(struct stm_data *stm_data,
380 				    unsigned int master,
381 				    unsigned int channel,
382 				    unsigned int nr_chans,
383 				    unsigned long options)
384 {
385 	struct stm_drvdata *drvdata = container_of(stm_data,
386 						   struct stm_drvdata, stm);
387 	if (!(drvdata && local_read(&drvdata->mode)))
388 		return -EINVAL;
389 
390 	if (channel >= drvdata->numsp)
391 		return -EINVAL;
392 
393 	switch (options) {
394 	case STM_OPTION_GUARANTEED:
395 		set_bit(channel, drvdata->chs.guaranteed);
396 		break;
397 
398 	case STM_OPTION_INVARIANT:
399 		clear_bit(channel, drvdata->chs.guaranteed);
400 		break;
401 
402 	default:
403 		return -EINVAL;
404 	}
405 
406 	return 0;
407 }
408 
409 static ssize_t notrace stm_generic_packet(struct stm_data *stm_data,
410 				  unsigned int master,
411 				  unsigned int channel,
412 				  unsigned int packet,
413 				  unsigned int flags,
414 				  unsigned int size,
415 				  const unsigned char *payload)
416 {
417 	unsigned long ch_addr;
418 	struct stm_drvdata *drvdata = container_of(stm_data,
419 						   struct stm_drvdata, stm);
420 
421 	if (!(drvdata && local_read(&drvdata->mode)))
422 		return -EACCES;
423 
424 	if (channel >= drvdata->numsp)
425 		return -EINVAL;
426 
427 	ch_addr = (unsigned long)stm_channel_addr(drvdata, channel);
428 
429 	flags = (flags == STP_PACKET_TIMESTAMPED) ? STM_FLAG_TIMESTAMPED : 0;
430 	flags |= test_bit(channel, drvdata->chs.guaranteed) ?
431 			   STM_FLAG_GUARANTEED : 0;
432 
433 	if (size > drvdata->write_bytes)
434 		size = drvdata->write_bytes;
435 	else
436 		size = rounddown_pow_of_two(size);
437 
438 	switch (packet) {
439 	case STP_PACKET_FLAG:
440 		ch_addr |= stm_channel_off(STM_PKT_TYPE_FLAG, flags);
441 
442 		/*
443 		 * The generic STM core sets a size of '0' on flag packets.
444 		 * As such send a flag packet of size '1' and tell the
445 		 * core we did so.
446 		 */
447 		stm_send((void *)ch_addr, payload, 1, drvdata->write_bytes);
448 		size = 1;
449 		break;
450 
451 	case STP_PACKET_DATA:
452 		ch_addr |= stm_channel_off(STM_PKT_TYPE_DATA, flags);
453 		stm_send((void *)ch_addr, payload, size,
454 				drvdata->write_bytes);
455 		break;
456 
457 	default:
458 		return -ENOTSUPP;
459 	}
460 
461 	return size;
462 }
463 
464 static ssize_t hwevent_enable_show(struct device *dev,
465 				   struct device_attribute *attr, char *buf)
466 {
467 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
468 	unsigned long val = drvdata->stmheer;
469 
470 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
471 }
472 
473 static ssize_t hwevent_enable_store(struct device *dev,
474 				    struct device_attribute *attr,
475 				    const char *buf, size_t size)
476 {
477 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
478 	unsigned long val;
479 	int ret = 0;
480 
481 	ret = kstrtoul(buf, 16, &val);
482 	if (ret)
483 		return -EINVAL;
484 
485 	drvdata->stmheer = val;
486 	/* HW event enable and trigger go hand in hand */
487 	drvdata->stmheter = val;
488 
489 	return size;
490 }
491 static DEVICE_ATTR_RW(hwevent_enable);
492 
493 static ssize_t hwevent_select_show(struct device *dev,
494 				   struct device_attribute *attr, char *buf)
495 {
496 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
497 	unsigned long val = drvdata->stmhebsr;
498 
499 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
500 }
501 
502 static ssize_t hwevent_select_store(struct device *dev,
503 				    struct device_attribute *attr,
504 				    const char *buf, size_t size)
505 {
506 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
507 	unsigned long val;
508 	int ret = 0;
509 
510 	ret = kstrtoul(buf, 16, &val);
511 	if (ret)
512 		return -EINVAL;
513 
514 	drvdata->stmhebsr = val;
515 
516 	return size;
517 }
518 static DEVICE_ATTR_RW(hwevent_select);
519 
520 static ssize_t port_select_show(struct device *dev,
521 				struct device_attribute *attr, char *buf)
522 {
523 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
524 	unsigned long val;
525 
526 	if (!local_read(&drvdata->mode)) {
527 		val = drvdata->stmspscr;
528 	} else {
529 		spin_lock(&drvdata->spinlock);
530 		val = readl_relaxed(drvdata->base + STMSPSCR);
531 		spin_unlock(&drvdata->spinlock);
532 	}
533 
534 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
535 }
536 
537 static ssize_t port_select_store(struct device *dev,
538 				 struct device_attribute *attr,
539 				 const char *buf, size_t size)
540 {
541 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
542 	unsigned long val, stmsper;
543 	int ret = 0;
544 
545 	ret = kstrtoul(buf, 16, &val);
546 	if (ret)
547 		return ret;
548 
549 	spin_lock(&drvdata->spinlock);
550 	drvdata->stmspscr = val;
551 
552 	if (local_read(&drvdata->mode)) {
553 		CS_UNLOCK(drvdata->base);
554 		/* Process as per ARM's TRM recommendation */
555 		stmsper = readl_relaxed(drvdata->base + STMSPER);
556 		writel_relaxed(0x0, drvdata->base + STMSPER);
557 		writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
558 		writel_relaxed(stmsper, drvdata->base + STMSPER);
559 		CS_LOCK(drvdata->base);
560 	}
561 	spin_unlock(&drvdata->spinlock);
562 
563 	return size;
564 }
565 static DEVICE_ATTR_RW(port_select);
566 
567 static ssize_t port_enable_show(struct device *dev,
568 				struct device_attribute *attr, char *buf)
569 {
570 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
571 	unsigned long val;
572 
573 	if (!local_read(&drvdata->mode)) {
574 		val = drvdata->stmsper;
575 	} else {
576 		spin_lock(&drvdata->spinlock);
577 		val = readl_relaxed(drvdata->base + STMSPER);
578 		spin_unlock(&drvdata->spinlock);
579 	}
580 
581 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
582 }
583 
584 static ssize_t port_enable_store(struct device *dev,
585 				 struct device_attribute *attr,
586 				 const char *buf, size_t size)
587 {
588 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
589 	unsigned long val;
590 	int ret = 0;
591 
592 	ret = kstrtoul(buf, 16, &val);
593 	if (ret)
594 		return ret;
595 
596 	spin_lock(&drvdata->spinlock);
597 	drvdata->stmsper = val;
598 
599 	if (local_read(&drvdata->mode)) {
600 		CS_UNLOCK(drvdata->base);
601 		writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
602 		CS_LOCK(drvdata->base);
603 	}
604 	spin_unlock(&drvdata->spinlock);
605 
606 	return size;
607 }
608 static DEVICE_ATTR_RW(port_enable);
609 
610 static ssize_t traceid_show(struct device *dev,
611 			    struct device_attribute *attr, char *buf)
612 {
613 	unsigned long val;
614 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
615 
616 	val = drvdata->traceid;
617 	return sprintf(buf, "%#lx\n", val);
618 }
619 
620 static ssize_t traceid_store(struct device *dev,
621 			     struct device_attribute *attr,
622 			     const char *buf, size_t size)
623 {
624 	int ret;
625 	unsigned long val;
626 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
627 
628 	ret = kstrtoul(buf, 16, &val);
629 	if (ret)
630 		return ret;
631 
632 	/* traceid field is 7bit wide on STM32 */
633 	drvdata->traceid = val & 0x7f;
634 	return size;
635 }
636 static DEVICE_ATTR_RW(traceid);
637 
638 #define coresight_stm_simple_func(name, offset)	\
639 	coresight_simple_func(struct stm_drvdata, NULL, name, offset)
640 
641 coresight_stm_simple_func(tcsr, STMTCSR);
642 coresight_stm_simple_func(tsfreqr, STMTSFREQR);
643 coresight_stm_simple_func(syncr, STMSYNCR);
644 coresight_stm_simple_func(sper, STMSPER);
645 coresight_stm_simple_func(spter, STMSPTER);
646 coresight_stm_simple_func(privmaskr, STMPRIVMASKR);
647 coresight_stm_simple_func(spscr, STMSPSCR);
648 coresight_stm_simple_func(spmscr, STMSPMSCR);
649 coresight_stm_simple_func(spfeat1r, STMSPFEAT1R);
650 coresight_stm_simple_func(spfeat2r, STMSPFEAT2R);
651 coresight_stm_simple_func(spfeat3r, STMSPFEAT3R);
652 coresight_stm_simple_func(devid, CORESIGHT_DEVID);
653 
654 static struct attribute *coresight_stm_attrs[] = {
655 	&dev_attr_hwevent_enable.attr,
656 	&dev_attr_hwevent_select.attr,
657 	&dev_attr_port_enable.attr,
658 	&dev_attr_port_select.attr,
659 	&dev_attr_traceid.attr,
660 	NULL,
661 };
662 
663 static struct attribute *coresight_stm_mgmt_attrs[] = {
664 	&dev_attr_tcsr.attr,
665 	&dev_attr_tsfreqr.attr,
666 	&dev_attr_syncr.attr,
667 	&dev_attr_sper.attr,
668 	&dev_attr_spter.attr,
669 	&dev_attr_privmaskr.attr,
670 	&dev_attr_spscr.attr,
671 	&dev_attr_spmscr.attr,
672 	&dev_attr_spfeat1r.attr,
673 	&dev_attr_spfeat2r.attr,
674 	&dev_attr_spfeat3r.attr,
675 	&dev_attr_devid.attr,
676 	NULL,
677 };
678 
679 static const struct attribute_group coresight_stm_group = {
680 	.attrs = coresight_stm_attrs,
681 };
682 
683 static const struct attribute_group coresight_stm_mgmt_group = {
684 	.attrs = coresight_stm_mgmt_attrs,
685 	.name = "mgmt",
686 };
687 
688 static const struct attribute_group *coresight_stm_groups[] = {
689 	&coresight_stm_group,
690 	&coresight_stm_mgmt_group,
691 	NULL,
692 };
693 
694 static int stm_get_resource_byname(struct device_node *np,
695 				   char *ch_base, struct resource *res)
696 {
697 	const char *name = NULL;
698 	int index = 0, found = 0;
699 
700 	while (!of_property_read_string_index(np, "reg-names", index, &name)) {
701 		if (strcmp(ch_base, name)) {
702 			index++;
703 			continue;
704 		}
705 
706 		/* We have a match and @index is where it's at */
707 		found = 1;
708 		break;
709 	}
710 
711 	if (!found)
712 		return -EINVAL;
713 
714 	return of_address_to_resource(np, index, res);
715 }
716 
717 static u32 stm_fundamental_data_size(struct stm_drvdata *drvdata)
718 {
719 	u32 stmspfeat2r;
720 
721 	if (!IS_ENABLED(CONFIG_64BIT))
722 		return 4;
723 
724 	stmspfeat2r = readl_relaxed(drvdata->base + STMSPFEAT2R);
725 
726 	/*
727 	 * bit[15:12] represents the fundamental data size
728 	 * 0 - 32-bit data
729 	 * 1 - 64-bit data
730 	 */
731 	return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
732 }
733 
734 static u32 stm_num_stimulus_port(struct stm_drvdata *drvdata)
735 {
736 	u32 numsp;
737 
738 	numsp = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
739 	/*
740 	 * NUMPS in STMDEVID is 17 bit long and if equal to 0x0,
741 	 * 32 stimulus ports are supported.
742 	 */
743 	numsp &= 0x1ffff;
744 	if (!numsp)
745 		numsp = STM_32_CHANNEL;
746 	return numsp;
747 }
748 
749 static void stm_init_default_data(struct stm_drvdata *drvdata)
750 {
751 	/* Don't use port selection */
752 	drvdata->stmspscr = 0x0;
753 	/*
754 	 * Enable all channel regardless of their number.  When port
755 	 * selection isn't used (see above) STMSPER applies to all
756 	 * 32 channel group available, hence setting all 32 bits to 1
757 	 */
758 	drvdata->stmsper = ~0x0;
759 
760 	/*
761 	 * The trace ID value for *ETM* tracers start at CPU_ID * 2 + 0x10 and
762 	 * anything equal to or higher than 0x70 is reserved.  Since 0x00 is
763 	 * also reserved the STM trace ID needs to be higher than 0x00 and
764 	 * lowner than 0x10.
765 	 */
766 	drvdata->traceid = 0x1;
767 
768 	/* Set invariant transaction timing on all channels */
769 	bitmap_clear(drvdata->chs.guaranteed, 0, drvdata->numsp);
770 }
771 
772 static void stm_init_generic_data(struct stm_drvdata *drvdata)
773 {
774 	drvdata->stm.name = dev_name(drvdata->dev);
775 
776 	/*
777 	 * MasterIDs are assigned at HW design phase. As such the core is
778 	 * using a single master for interaction with this device.
779 	 */
780 	drvdata->stm.sw_start = 1;
781 	drvdata->stm.sw_end = 1;
782 	drvdata->stm.hw_override = true;
783 	drvdata->stm.sw_nchannels = drvdata->numsp;
784 	drvdata->stm.sw_mmiosz = BYTES_PER_CHANNEL;
785 	drvdata->stm.packet = stm_generic_packet;
786 	drvdata->stm.mmio_addr = stm_mmio_addr;
787 	drvdata->stm.link = stm_generic_link;
788 	drvdata->stm.unlink = stm_generic_unlink;
789 	drvdata->stm.set_options = stm_generic_set_options;
790 }
791 
792 static int stm_probe(struct amba_device *adev, const struct amba_id *id)
793 {
794 	int ret;
795 	void __iomem *base;
796 	unsigned long *guaranteed;
797 	struct device *dev = &adev->dev;
798 	struct coresight_platform_data *pdata = NULL;
799 	struct stm_drvdata *drvdata;
800 	struct resource *res = &adev->res;
801 	struct resource ch_res;
802 	size_t res_size, bitmap_size;
803 	struct coresight_desc desc = { 0 };
804 	struct device_node *np = adev->dev.of_node;
805 
806 	if (np) {
807 		pdata = of_get_coresight_platform_data(dev, np);
808 		if (IS_ERR(pdata))
809 			return PTR_ERR(pdata);
810 		adev->dev.platform_data = pdata;
811 	}
812 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
813 	if (!drvdata)
814 		return -ENOMEM;
815 
816 	drvdata->dev = &adev->dev;
817 	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
818 	if (!IS_ERR(drvdata->atclk)) {
819 		ret = clk_prepare_enable(drvdata->atclk);
820 		if (ret)
821 			return ret;
822 	}
823 	dev_set_drvdata(dev, drvdata);
824 
825 	base = devm_ioremap_resource(dev, res);
826 	if (IS_ERR(base))
827 		return PTR_ERR(base);
828 	drvdata->base = base;
829 
830 	ret = stm_get_resource_byname(np, "stm-stimulus-base", &ch_res);
831 	if (ret)
832 		return ret;
833 	drvdata->chs.phys = ch_res.start;
834 
835 	base = devm_ioremap_resource(dev, &ch_res);
836 	if (IS_ERR(base))
837 		return PTR_ERR(base);
838 	drvdata->chs.base = base;
839 
840 	drvdata->write_bytes = stm_fundamental_data_size(drvdata);
841 
842 	if (boot_nr_channel) {
843 		drvdata->numsp = boot_nr_channel;
844 		res_size = min((resource_size_t)(boot_nr_channel *
845 				  BYTES_PER_CHANNEL), resource_size(res));
846 	} else {
847 		drvdata->numsp = stm_num_stimulus_port(drvdata);
848 		res_size = min((resource_size_t)(drvdata->numsp *
849 				 BYTES_PER_CHANNEL), resource_size(res));
850 	}
851 	bitmap_size = BITS_TO_LONGS(drvdata->numsp) * sizeof(long);
852 
853 	guaranteed = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
854 	if (!guaranteed)
855 		return -ENOMEM;
856 	drvdata->chs.guaranteed = guaranteed;
857 
858 	spin_lock_init(&drvdata->spinlock);
859 
860 	stm_init_default_data(drvdata);
861 	stm_init_generic_data(drvdata);
862 
863 	if (stm_register_device(dev, &drvdata->stm, THIS_MODULE)) {
864 		dev_info(dev,
865 			 "stm_register_device failed, probing deffered\n");
866 		return -EPROBE_DEFER;
867 	}
868 
869 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
870 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE;
871 	desc.ops = &stm_cs_ops;
872 	desc.pdata = pdata;
873 	desc.dev = dev;
874 	desc.groups = coresight_stm_groups;
875 	drvdata->csdev = coresight_register(&desc);
876 	if (IS_ERR(drvdata->csdev)) {
877 		ret = PTR_ERR(drvdata->csdev);
878 		goto stm_unregister;
879 	}
880 
881 	pm_runtime_put(&adev->dev);
882 
883 	dev_info(dev, "%s initialized\n", (char *)id->data);
884 	return 0;
885 
886 stm_unregister:
887 	stm_unregister_device(&drvdata->stm);
888 	return ret;
889 }
890 
891 #ifdef CONFIG_PM
892 static int stm_runtime_suspend(struct device *dev)
893 {
894 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
895 
896 	if (drvdata && !IS_ERR(drvdata->atclk))
897 		clk_disable_unprepare(drvdata->atclk);
898 
899 	return 0;
900 }
901 
902 static int stm_runtime_resume(struct device *dev)
903 {
904 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
905 
906 	if (drvdata && !IS_ERR(drvdata->atclk))
907 		clk_prepare_enable(drvdata->atclk);
908 
909 	return 0;
910 }
911 #endif
912 
913 static const struct dev_pm_ops stm_dev_pm_ops = {
914 	SET_RUNTIME_PM_OPS(stm_runtime_suspend, stm_runtime_resume, NULL)
915 };
916 
917 static struct amba_id stm_ids[] = {
918 	{
919 		.id     = 0x0003b962,
920 		.mask   = 0x0003ffff,
921 		.data	= "STM32",
922 	},
923 	{
924 		.id	= 0x0003b963,
925 		.mask	= 0x0003ffff,
926 		.data	= "STM500",
927 	},
928 	{ 0, 0},
929 };
930 
931 static struct amba_driver stm_driver = {
932 	.drv = {
933 		.name   = "coresight-stm",
934 		.owner	= THIS_MODULE,
935 		.pm	= &stm_dev_pm_ops,
936 		.suppress_bind_attrs = true,
937 	},
938 	.probe          = stm_probe,
939 	.id_table	= stm_ids,
940 };
941 
942 builtin_amba_driver(stm_driver);
943