xref: /openbmc/linux/drivers/hwtracing/coresight/coresight-stm.c (revision 93707cbabcc8baf2b2b5f4a99c1f08ee83eb7abd)
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->base, 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 __iomem *addr, const void *data,
311 		     u32 size, u8 write_bytes)
312 {
313 	u8 paload[8];
314 
315 	if (stm_addr_unaligned(data, write_bytes)) {
316 		memcpy(paload, data, size);
317 		data = paload;
318 	}
319 
320 	/* now we are 64bit/32bit aligned */
321 	switch (size) {
322 #ifdef CONFIG_64BIT
323 	case 8:
324 		writeq_relaxed(*(u64 *)data, addr);
325 		break;
326 #endif
327 	case 4:
328 		writel_relaxed(*(u32 *)data, addr);
329 		break;
330 	case 2:
331 		writew_relaxed(*(u16 *)data, addr);
332 		break;
333 	case 1:
334 		writeb_relaxed(*(u8 *)data, addr);
335 		break;
336 	default:
337 		break;
338 	}
339 }
340 
341 static int stm_generic_link(struct stm_data *stm_data,
342 			    unsigned int master,  unsigned int channel)
343 {
344 	struct stm_drvdata *drvdata = container_of(stm_data,
345 						   struct stm_drvdata, stm);
346 	if (!drvdata || !drvdata->csdev)
347 		return -EINVAL;
348 
349 	return coresight_enable(drvdata->csdev);
350 }
351 
352 static void stm_generic_unlink(struct stm_data *stm_data,
353 			       unsigned int master,  unsigned int channel)
354 {
355 	struct stm_drvdata *drvdata = container_of(stm_data,
356 						   struct stm_drvdata, stm);
357 	if (!drvdata || !drvdata->csdev)
358 		return;
359 
360 	coresight_disable(drvdata->csdev);
361 }
362 
363 static phys_addr_t
364 stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
365 	      unsigned int channel, unsigned int nr_chans)
366 {
367 	struct stm_drvdata *drvdata = container_of(stm_data,
368 						   struct stm_drvdata, stm);
369 	phys_addr_t addr;
370 
371 	addr = drvdata->chs.phys + channel * BYTES_PER_CHANNEL;
372 
373 	if (offset_in_page(addr) ||
374 	    offset_in_page(nr_chans * BYTES_PER_CHANNEL))
375 		return 0;
376 
377 	return addr;
378 }
379 
380 static long stm_generic_set_options(struct stm_data *stm_data,
381 				    unsigned int master,
382 				    unsigned int channel,
383 				    unsigned int nr_chans,
384 				    unsigned long options)
385 {
386 	struct stm_drvdata *drvdata = container_of(stm_data,
387 						   struct stm_drvdata, stm);
388 	if (!(drvdata && local_read(&drvdata->mode)))
389 		return -EINVAL;
390 
391 	if (channel >= drvdata->numsp)
392 		return -EINVAL;
393 
394 	switch (options) {
395 	case STM_OPTION_GUARANTEED:
396 		set_bit(channel, drvdata->chs.guaranteed);
397 		break;
398 
399 	case STM_OPTION_INVARIANT:
400 		clear_bit(channel, drvdata->chs.guaranteed);
401 		break;
402 
403 	default:
404 		return -EINVAL;
405 	}
406 
407 	return 0;
408 }
409 
410 static ssize_t notrace stm_generic_packet(struct stm_data *stm_data,
411 				  unsigned int master,
412 				  unsigned int channel,
413 				  unsigned int packet,
414 				  unsigned int flags,
415 				  unsigned int size,
416 				  const unsigned char *payload)
417 {
418 	void __iomem *ch_addr;
419 	struct stm_drvdata *drvdata = container_of(stm_data,
420 						   struct stm_drvdata, stm);
421 
422 	if (!(drvdata && local_read(&drvdata->mode)))
423 		return -EACCES;
424 
425 	if (channel >= drvdata->numsp)
426 		return -EINVAL;
427 
428 	ch_addr = stm_channel_addr(drvdata, channel);
429 
430 	flags = (flags == STP_PACKET_TIMESTAMPED) ? STM_FLAG_TIMESTAMPED : 0;
431 	flags |= test_bit(channel, drvdata->chs.guaranteed) ?
432 			   STM_FLAG_GUARANTEED : 0;
433 
434 	if (size > drvdata->write_bytes)
435 		size = drvdata->write_bytes;
436 	else
437 		size = rounddown_pow_of_two(size);
438 
439 	switch (packet) {
440 	case STP_PACKET_FLAG:
441 		ch_addr += stm_channel_off(STM_PKT_TYPE_FLAG, flags);
442 
443 		/*
444 		 * The generic STM core sets a size of '0' on flag packets.
445 		 * As such send a flag packet of size '1' and tell the
446 		 * core we did so.
447 		 */
448 		stm_send(ch_addr, payload, 1, drvdata->write_bytes);
449 		size = 1;
450 		break;
451 
452 	case STP_PACKET_DATA:
453 		ch_addr += stm_channel_off(STM_PKT_TYPE_DATA, flags);
454 		stm_send(ch_addr, payload, size,
455 				drvdata->write_bytes);
456 		break;
457 
458 	default:
459 		return -ENOTSUPP;
460 	}
461 
462 	return size;
463 }
464 
465 static ssize_t hwevent_enable_show(struct device *dev,
466 				   struct device_attribute *attr, char *buf)
467 {
468 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
469 	unsigned long val = drvdata->stmheer;
470 
471 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
472 }
473 
474 static ssize_t hwevent_enable_store(struct device *dev,
475 				    struct device_attribute *attr,
476 				    const char *buf, size_t size)
477 {
478 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
479 	unsigned long val;
480 	int ret = 0;
481 
482 	ret = kstrtoul(buf, 16, &val);
483 	if (ret)
484 		return -EINVAL;
485 
486 	drvdata->stmheer = val;
487 	/* HW event enable and trigger go hand in hand */
488 	drvdata->stmheter = val;
489 
490 	return size;
491 }
492 static DEVICE_ATTR_RW(hwevent_enable);
493 
494 static ssize_t hwevent_select_show(struct device *dev,
495 				   struct device_attribute *attr, char *buf)
496 {
497 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
498 	unsigned long val = drvdata->stmhebsr;
499 
500 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
501 }
502 
503 static ssize_t hwevent_select_store(struct device *dev,
504 				    struct device_attribute *attr,
505 				    const char *buf, size_t size)
506 {
507 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
508 	unsigned long val;
509 	int ret = 0;
510 
511 	ret = kstrtoul(buf, 16, &val);
512 	if (ret)
513 		return -EINVAL;
514 
515 	drvdata->stmhebsr = val;
516 
517 	return size;
518 }
519 static DEVICE_ATTR_RW(hwevent_select);
520 
521 static ssize_t port_select_show(struct device *dev,
522 				struct device_attribute *attr, char *buf)
523 {
524 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
525 	unsigned long val;
526 
527 	if (!local_read(&drvdata->mode)) {
528 		val = drvdata->stmspscr;
529 	} else {
530 		spin_lock(&drvdata->spinlock);
531 		val = readl_relaxed(drvdata->base + STMSPSCR);
532 		spin_unlock(&drvdata->spinlock);
533 	}
534 
535 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
536 }
537 
538 static ssize_t port_select_store(struct device *dev,
539 				 struct device_attribute *attr,
540 				 const char *buf, size_t size)
541 {
542 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
543 	unsigned long val, stmsper;
544 	int ret = 0;
545 
546 	ret = kstrtoul(buf, 16, &val);
547 	if (ret)
548 		return ret;
549 
550 	spin_lock(&drvdata->spinlock);
551 	drvdata->stmspscr = val;
552 
553 	if (local_read(&drvdata->mode)) {
554 		CS_UNLOCK(drvdata->base);
555 		/* Process as per ARM's TRM recommendation */
556 		stmsper = readl_relaxed(drvdata->base + STMSPER);
557 		writel_relaxed(0x0, drvdata->base + STMSPER);
558 		writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
559 		writel_relaxed(stmsper, drvdata->base + STMSPER);
560 		CS_LOCK(drvdata->base);
561 	}
562 	spin_unlock(&drvdata->spinlock);
563 
564 	return size;
565 }
566 static DEVICE_ATTR_RW(port_select);
567 
568 static ssize_t port_enable_show(struct device *dev,
569 				struct device_attribute *attr, char *buf)
570 {
571 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
572 	unsigned long val;
573 
574 	if (!local_read(&drvdata->mode)) {
575 		val = drvdata->stmsper;
576 	} else {
577 		spin_lock(&drvdata->spinlock);
578 		val = readl_relaxed(drvdata->base + STMSPER);
579 		spin_unlock(&drvdata->spinlock);
580 	}
581 
582 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
583 }
584 
585 static ssize_t port_enable_store(struct device *dev,
586 				 struct device_attribute *attr,
587 				 const char *buf, size_t size)
588 {
589 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
590 	unsigned long val;
591 	int ret = 0;
592 
593 	ret = kstrtoul(buf, 16, &val);
594 	if (ret)
595 		return ret;
596 
597 	spin_lock(&drvdata->spinlock);
598 	drvdata->stmsper = val;
599 
600 	if (local_read(&drvdata->mode)) {
601 		CS_UNLOCK(drvdata->base);
602 		writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
603 		CS_LOCK(drvdata->base);
604 	}
605 	spin_unlock(&drvdata->spinlock);
606 
607 	return size;
608 }
609 static DEVICE_ATTR_RW(port_enable);
610 
611 static ssize_t traceid_show(struct device *dev,
612 			    struct device_attribute *attr, char *buf)
613 {
614 	unsigned long val;
615 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
616 
617 	val = drvdata->traceid;
618 	return sprintf(buf, "%#lx\n", val);
619 }
620 
621 static ssize_t traceid_store(struct device *dev,
622 			     struct device_attribute *attr,
623 			     const char *buf, size_t size)
624 {
625 	int ret;
626 	unsigned long val;
627 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
628 
629 	ret = kstrtoul(buf, 16, &val);
630 	if (ret)
631 		return ret;
632 
633 	/* traceid field is 7bit wide on STM32 */
634 	drvdata->traceid = val & 0x7f;
635 	return size;
636 }
637 static DEVICE_ATTR_RW(traceid);
638 
639 #define coresight_stm_reg(name, offset)	\
640 	coresight_simple_reg32(struct stm_drvdata, name, offset)
641 
642 coresight_stm_reg(tcsr, STMTCSR);
643 coresight_stm_reg(tsfreqr, STMTSFREQR);
644 coresight_stm_reg(syncr, STMSYNCR);
645 coresight_stm_reg(sper, STMSPER);
646 coresight_stm_reg(spter, STMSPTER);
647 coresight_stm_reg(privmaskr, STMPRIVMASKR);
648 coresight_stm_reg(spscr, STMSPSCR);
649 coresight_stm_reg(spmscr, STMSPMSCR);
650 coresight_stm_reg(spfeat1r, STMSPFEAT1R);
651 coresight_stm_reg(spfeat2r, STMSPFEAT2R);
652 coresight_stm_reg(spfeat3r, STMSPFEAT3R);
653 coresight_stm_reg(devid, CORESIGHT_DEVID);
654 
655 static struct attribute *coresight_stm_attrs[] = {
656 	&dev_attr_hwevent_enable.attr,
657 	&dev_attr_hwevent_select.attr,
658 	&dev_attr_port_enable.attr,
659 	&dev_attr_port_select.attr,
660 	&dev_attr_traceid.attr,
661 	NULL,
662 };
663 
664 static struct attribute *coresight_stm_mgmt_attrs[] = {
665 	&dev_attr_tcsr.attr,
666 	&dev_attr_tsfreqr.attr,
667 	&dev_attr_syncr.attr,
668 	&dev_attr_sper.attr,
669 	&dev_attr_spter.attr,
670 	&dev_attr_privmaskr.attr,
671 	&dev_attr_spscr.attr,
672 	&dev_attr_spmscr.attr,
673 	&dev_attr_spfeat1r.attr,
674 	&dev_attr_spfeat2r.attr,
675 	&dev_attr_spfeat3r.attr,
676 	&dev_attr_devid.attr,
677 	NULL,
678 };
679 
680 static const struct attribute_group coresight_stm_group = {
681 	.attrs = coresight_stm_attrs,
682 };
683 
684 static const struct attribute_group coresight_stm_mgmt_group = {
685 	.attrs = coresight_stm_mgmt_attrs,
686 	.name = "mgmt",
687 };
688 
689 static const struct attribute_group *coresight_stm_groups[] = {
690 	&coresight_stm_group,
691 	&coresight_stm_mgmt_group,
692 	NULL,
693 };
694 
695 static int stm_get_resource_byname(struct device_node *np,
696 				   char *ch_base, struct resource *res)
697 {
698 	const char *name = NULL;
699 	int index = 0, found = 0;
700 
701 	while (!of_property_read_string_index(np, "reg-names", index, &name)) {
702 		if (strcmp(ch_base, name)) {
703 			index++;
704 			continue;
705 		}
706 
707 		/* We have a match and @index is where it's at */
708 		found = 1;
709 		break;
710 	}
711 
712 	if (!found)
713 		return -EINVAL;
714 
715 	return of_address_to_resource(np, index, res);
716 }
717 
718 static u32 stm_fundamental_data_size(struct stm_drvdata *drvdata)
719 {
720 	u32 stmspfeat2r;
721 
722 	if (!IS_ENABLED(CONFIG_64BIT))
723 		return 4;
724 
725 	stmspfeat2r = readl_relaxed(drvdata->base + STMSPFEAT2R);
726 
727 	/*
728 	 * bit[15:12] represents the fundamental data size
729 	 * 0 - 32-bit data
730 	 * 1 - 64-bit data
731 	 */
732 	return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
733 }
734 
735 static u32 stm_num_stimulus_port(struct stm_drvdata *drvdata)
736 {
737 	u32 numsp;
738 
739 	numsp = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
740 	/*
741 	 * NUMPS in STMDEVID is 17 bit long and if equal to 0x0,
742 	 * 32 stimulus ports are supported.
743 	 */
744 	numsp &= 0x1ffff;
745 	if (!numsp)
746 		numsp = STM_32_CHANNEL;
747 	return numsp;
748 }
749 
750 static void stm_init_default_data(struct stm_drvdata *drvdata)
751 {
752 	/* Don't use port selection */
753 	drvdata->stmspscr = 0x0;
754 	/*
755 	 * Enable all channel regardless of their number.  When port
756 	 * selection isn't used (see above) STMSPER applies to all
757 	 * 32 channel group available, hence setting all 32 bits to 1
758 	 */
759 	drvdata->stmsper = ~0x0;
760 
761 	/*
762 	 * The trace ID value for *ETM* tracers start at CPU_ID * 2 + 0x10 and
763 	 * anything equal to or higher than 0x70 is reserved.  Since 0x00 is
764 	 * also reserved the STM trace ID needs to be higher than 0x00 and
765 	 * lowner than 0x10.
766 	 */
767 	drvdata->traceid = 0x1;
768 
769 	/* Set invariant transaction timing on all channels */
770 	bitmap_clear(drvdata->chs.guaranteed, 0, drvdata->numsp);
771 }
772 
773 static void stm_init_generic_data(struct stm_drvdata *drvdata)
774 {
775 	drvdata->stm.name = dev_name(drvdata->dev);
776 
777 	/*
778 	 * MasterIDs are assigned at HW design phase. As such the core is
779 	 * using a single master for interaction with this device.
780 	 */
781 	drvdata->stm.sw_start = 1;
782 	drvdata->stm.sw_end = 1;
783 	drvdata->stm.hw_override = true;
784 	drvdata->stm.sw_nchannels = drvdata->numsp;
785 	drvdata->stm.sw_mmiosz = BYTES_PER_CHANNEL;
786 	drvdata->stm.packet = stm_generic_packet;
787 	drvdata->stm.mmio_addr = stm_mmio_addr;
788 	drvdata->stm.link = stm_generic_link;
789 	drvdata->stm.unlink = stm_generic_unlink;
790 	drvdata->stm.set_options = stm_generic_set_options;
791 }
792 
793 static int stm_probe(struct amba_device *adev, const struct amba_id *id)
794 {
795 	int ret;
796 	void __iomem *base;
797 	unsigned long *guaranteed;
798 	struct device *dev = &adev->dev;
799 	struct coresight_platform_data *pdata = NULL;
800 	struct stm_drvdata *drvdata;
801 	struct resource *res = &adev->res;
802 	struct resource ch_res;
803 	size_t res_size, bitmap_size;
804 	struct coresight_desc desc = { 0 };
805 	struct device_node *np = adev->dev.of_node;
806 
807 	if (np) {
808 		pdata = of_get_coresight_platform_data(dev, np);
809 		if (IS_ERR(pdata))
810 			return PTR_ERR(pdata);
811 		adev->dev.platform_data = pdata;
812 	}
813 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
814 	if (!drvdata)
815 		return -ENOMEM;
816 
817 	drvdata->dev = &adev->dev;
818 	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
819 	if (!IS_ERR(drvdata->atclk)) {
820 		ret = clk_prepare_enable(drvdata->atclk);
821 		if (ret)
822 			return ret;
823 	}
824 	dev_set_drvdata(dev, drvdata);
825 
826 	base = devm_ioremap_resource(dev, res);
827 	if (IS_ERR(base))
828 		return PTR_ERR(base);
829 	drvdata->base = base;
830 
831 	ret = stm_get_resource_byname(np, "stm-stimulus-base", &ch_res);
832 	if (ret)
833 		return ret;
834 	drvdata->chs.phys = ch_res.start;
835 
836 	base = devm_ioremap_resource(dev, &ch_res);
837 	if (IS_ERR(base))
838 		return PTR_ERR(base);
839 	drvdata->chs.base = base;
840 
841 	drvdata->write_bytes = stm_fundamental_data_size(drvdata);
842 
843 	if (boot_nr_channel) {
844 		drvdata->numsp = boot_nr_channel;
845 		res_size = min((resource_size_t)(boot_nr_channel *
846 				  BYTES_PER_CHANNEL), resource_size(res));
847 	} else {
848 		drvdata->numsp = stm_num_stimulus_port(drvdata);
849 		res_size = min((resource_size_t)(drvdata->numsp *
850 				 BYTES_PER_CHANNEL), resource_size(res));
851 	}
852 	bitmap_size = BITS_TO_LONGS(drvdata->numsp) * sizeof(long);
853 
854 	guaranteed = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
855 	if (!guaranteed)
856 		return -ENOMEM;
857 	drvdata->chs.guaranteed = guaranteed;
858 
859 	spin_lock_init(&drvdata->spinlock);
860 
861 	stm_init_default_data(drvdata);
862 	stm_init_generic_data(drvdata);
863 
864 	if (stm_register_device(dev, &drvdata->stm, THIS_MODULE)) {
865 		dev_info(dev,
866 			 "stm_register_device failed, probing deffered\n");
867 		return -EPROBE_DEFER;
868 	}
869 
870 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
871 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE;
872 	desc.ops = &stm_cs_ops;
873 	desc.pdata = pdata;
874 	desc.dev = dev;
875 	desc.groups = coresight_stm_groups;
876 	drvdata->csdev = coresight_register(&desc);
877 	if (IS_ERR(drvdata->csdev)) {
878 		ret = PTR_ERR(drvdata->csdev);
879 		goto stm_unregister;
880 	}
881 
882 	pm_runtime_put(&adev->dev);
883 
884 	dev_info(dev, "%s initialized\n", (char *)id->data);
885 	return 0;
886 
887 stm_unregister:
888 	stm_unregister_device(&drvdata->stm);
889 	return ret;
890 }
891 
892 #ifdef CONFIG_PM
893 static int stm_runtime_suspend(struct device *dev)
894 {
895 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
896 
897 	if (drvdata && !IS_ERR(drvdata->atclk))
898 		clk_disable_unprepare(drvdata->atclk);
899 
900 	return 0;
901 }
902 
903 static int stm_runtime_resume(struct device *dev)
904 {
905 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
906 
907 	if (drvdata && !IS_ERR(drvdata->atclk))
908 		clk_prepare_enable(drvdata->atclk);
909 
910 	return 0;
911 }
912 #endif
913 
914 static const struct dev_pm_ops stm_dev_pm_ops = {
915 	SET_RUNTIME_PM_OPS(stm_runtime_suspend, stm_runtime_resume, NULL)
916 };
917 
918 static const struct amba_id stm_ids[] = {
919 	{
920 		.id     = 0x000bb962,
921 		.mask   = 0x000fffff,
922 		.data	= "STM32",
923 	},
924 	{
925 		.id	= 0x000bb963,
926 		.mask	= 0x000fffff,
927 		.data	= "STM500",
928 	},
929 	{ 0, 0},
930 };
931 
932 static struct amba_driver stm_driver = {
933 	.drv = {
934 		.name   = "coresight-stm",
935 		.owner	= THIS_MODULE,
936 		.pm	= &stm_dev_pm_ops,
937 		.suppress_bind_attrs = true,
938 	},
939 	.probe          = stm_probe,
940 	.id_table	= stm_ids,
941 };
942 
943 builtin_amba_driver(stm_driver);
944