1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
4  *
5  * Description: CoreSight System Trace Macrocell driver
6  *
7  * Initial implementation by Pratik Patel
8  * (C) 2014-2015 Pratik Patel <pratikp@codeaurora.org>
9  *
10  * Serious refactoring, code cleanup and upgrading to the Coresight upstream
11  * framework by Mathieu Poirier
12  * (C) 2015-2016 Mathieu Poirier <mathieu.poirier@linaro.org>
13  *
14  * Guaranteed timing and support for various packet type coming from the
15  * generic STM API by Chunyan Zhang
16  * (C) 2015-2016 Chunyan Zhang <zhang.chunyan@linaro.org>
17  */
18 #include <asm/local.h>
19 #include <linux/acpi.h>
20 #include <linux/amba/bus.h>
21 #include <linux/bitmap.h>
22 #include <linux/clk.h>
23 #include <linux/coresight.h>
24 #include <linux/coresight-stm.h>
25 #include <linux/err.h>
26 #include <linux/kernel.h>
27 #include <linux/moduleparam.h>
28 #include <linux/of_address.h>
29 #include <linux/perf_event.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/stm.h>
32 
33 #include "coresight-priv.h"
34 
35 #define STMDMASTARTR			0xc04
36 #define STMDMASTOPR			0xc08
37 #define STMDMASTATR			0xc0c
38 #define STMDMACTLR			0xc10
39 #define STMDMAIDR			0xcfc
40 #define STMHEER				0xd00
41 #define STMHETER			0xd20
42 #define STMHEBSR			0xd60
43 #define STMHEMCR			0xd64
44 #define STMHEMASTR			0xdf4
45 #define STMHEFEAT1R			0xdf8
46 #define STMHEIDR			0xdfc
47 #define STMSPER				0xe00
48 #define STMSPTER			0xe20
49 #define STMPRIVMASKR			0xe40
50 #define STMSPSCR			0xe60
51 #define STMSPMSCR			0xe64
52 #define STMSPOVERRIDER			0xe68
53 #define STMSPMOVERRIDER			0xe6c
54 #define STMSPTRIGCSR			0xe70
55 #define STMTCSR				0xe80
56 #define STMTSSTIMR			0xe84
57 #define STMTSFREQR			0xe8c
58 #define STMSYNCR			0xe90
59 #define STMAUXCR			0xe94
60 #define STMSPFEAT1R			0xea0
61 #define STMSPFEAT2R			0xea4
62 #define STMSPFEAT3R			0xea8
63 #define STMITTRIGGER			0xee8
64 #define STMITATBDATA0			0xeec
65 #define STMITATBCTR2			0xef0
66 #define STMITATBID			0xef4
67 #define STMITATBCTR0			0xef8
68 
69 #define STM_32_CHANNEL			32
70 #define BYTES_PER_CHANNEL		256
71 #define STM_TRACE_BUF_SIZE		4096
72 #define STM_SW_MASTER_END		127
73 
74 /* Register bit definition */
75 #define STMTCSR_BUSY_BIT		23
76 /* Reserve the first 10 channels for kernel usage */
77 #define STM_CHANNEL_OFFSET		0
78 
79 enum stm_pkt_type {
80 	STM_PKT_TYPE_DATA	= 0x98,
81 	STM_PKT_TYPE_FLAG	= 0xE8,
82 	STM_PKT_TYPE_TRIG	= 0xF8,
83 };
84 
85 #define stm_channel_addr(drvdata, ch)	(drvdata->chs.base +	\
86 					(ch * BYTES_PER_CHANNEL))
87 #define stm_channel_off(type, opts)	(type & ~opts)
88 
89 static int boot_nr_channel;
90 
91 /*
92  * Not really modular but using module_param is the easiest way to
93  * remain consistent with existing use cases for now.
94  */
95 module_param_named(
96 	boot_nr_channel, boot_nr_channel, int, S_IRUGO
97 );
98 
99 /*
100  * struct channel_space - central management entity for extended ports
101  * @base:		memory mapped base address where channels start.
102  * @phys:		physical base address of channel region.
103  * @guaraneed:		is the channel delivery guaranteed.
104  */
105 struct channel_space {
106 	void __iomem		*base;
107 	phys_addr_t		phys;
108 	unsigned long		*guaranteed;
109 };
110 
111 DEFINE_CORESIGHT_DEVLIST(stm_devs, "stm");
112 
113 /**
114  * struct stm_drvdata - specifics associated to an STM component
115  * @base:		memory mapped base address for this component.
116  * @atclk:		optional clock for the core parts of the STM.
117  * @csdev:		component vitals needed by the framework.
118  * @spinlock:		only one at a time pls.
119  * @chs:		the channels accociated to this STM.
120  * @stm:		structure associated to the generic STM interface.
121  * @mode:		this tracer's mode, i.e sysFS, or disabled.
122  * @traceid:		value of the current ID for this component.
123  * @write_bytes:	Maximus bytes this STM can write at a time.
124  * @stmsper:		settings for register STMSPER.
125  * @stmspscr:		settings for register STMSPSCR.
126  * @numsp:		the total number of stimulus port support by this STM.
127  * @stmheer:		settings for register STMHEER.
128  * @stmheter:		settings for register STMHETER.
129  * @stmhebsr:		settings for register STMHEBSR.
130  */
131 struct stm_drvdata {
132 	void __iomem		*base;
133 	struct clk		*atclk;
134 	struct coresight_device	*csdev;
135 	spinlock_t		spinlock;
136 	struct channel_space	chs;
137 	struct stm_data		stm;
138 	local_t			mode;
139 	u8			traceid;
140 	u32			write_bytes;
141 	u32			stmsper;
142 	u32			stmspscr;
143 	u32			numsp;
144 	u32			stmheer;
145 	u32			stmheter;
146 	u32			stmhebsr;
147 };
148 
149 static void stm_hwevent_enable_hw(struct stm_drvdata *drvdata)
150 {
151 	CS_UNLOCK(drvdata->base);
152 
153 	writel_relaxed(drvdata->stmhebsr, drvdata->base + STMHEBSR);
154 	writel_relaxed(drvdata->stmheter, drvdata->base + STMHETER);
155 	writel_relaxed(drvdata->stmheer, drvdata->base + STMHEER);
156 	writel_relaxed(0x01 |	/* Enable HW event tracing */
157 		       0x04,	/* Error detection on event tracing */
158 		       drvdata->base + STMHEMCR);
159 
160 	CS_LOCK(drvdata->base);
161 }
162 
163 static void stm_port_enable_hw(struct stm_drvdata *drvdata)
164 {
165 	CS_UNLOCK(drvdata->base);
166 	/* ATB trigger enable on direct writes to TRIG locations */
167 	writel_relaxed(0x10,
168 		       drvdata->base + STMSPTRIGCSR);
169 	writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
170 	writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
171 
172 	CS_LOCK(drvdata->base);
173 }
174 
175 static void stm_enable_hw(struct stm_drvdata *drvdata)
176 {
177 	if (drvdata->stmheer)
178 		stm_hwevent_enable_hw(drvdata);
179 
180 	stm_port_enable_hw(drvdata);
181 
182 	CS_UNLOCK(drvdata->base);
183 
184 	/* 4096 byte between synchronisation packets */
185 	writel_relaxed(0xFFF, drvdata->base + STMSYNCR);
186 	writel_relaxed((drvdata->traceid << 16 | /* trace id */
187 			0x02 |			 /* timestamp enable */
188 			0x01),			 /* global STM enable */
189 			drvdata->base + STMTCSR);
190 
191 	CS_LOCK(drvdata->base);
192 }
193 
194 static int stm_enable(struct coresight_device *csdev,
195 		      struct perf_event *event, u32 mode)
196 {
197 	u32 val;
198 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
199 
200 	if (mode != CS_MODE_SYSFS)
201 		return -EINVAL;
202 
203 	val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode);
204 
205 	/* Someone is already using the tracer */
206 	if (val)
207 		return -EBUSY;
208 
209 	pm_runtime_get_sync(csdev->dev.parent);
210 
211 	spin_lock(&drvdata->spinlock);
212 	stm_enable_hw(drvdata);
213 	spin_unlock(&drvdata->spinlock);
214 
215 	dev_dbg(&csdev->dev, "STM tracing enabled\n");
216 	return 0;
217 }
218 
219 static void stm_hwevent_disable_hw(struct stm_drvdata *drvdata)
220 {
221 	CS_UNLOCK(drvdata->base);
222 
223 	writel_relaxed(0x0, drvdata->base + STMHEMCR);
224 	writel_relaxed(0x0, drvdata->base + STMHEER);
225 	writel_relaxed(0x0, drvdata->base + STMHETER);
226 
227 	CS_LOCK(drvdata->base);
228 }
229 
230 static void stm_port_disable_hw(struct stm_drvdata *drvdata)
231 {
232 	CS_UNLOCK(drvdata->base);
233 
234 	writel_relaxed(0x0, drvdata->base + STMSPER);
235 	writel_relaxed(0x0, drvdata->base + STMSPTRIGCSR);
236 
237 	CS_LOCK(drvdata->base);
238 }
239 
240 static void stm_disable_hw(struct stm_drvdata *drvdata)
241 {
242 	u32 val;
243 
244 	CS_UNLOCK(drvdata->base);
245 
246 	val = readl_relaxed(drvdata->base + STMTCSR);
247 	val &= ~0x1; /* clear global STM enable [0] */
248 	writel_relaxed(val, drvdata->base + STMTCSR);
249 
250 	CS_LOCK(drvdata->base);
251 
252 	stm_port_disable_hw(drvdata);
253 	if (drvdata->stmheer)
254 		stm_hwevent_disable_hw(drvdata);
255 }
256 
257 static void stm_disable(struct coresight_device *csdev,
258 			struct perf_event *event)
259 {
260 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
261 
262 	/*
263 	 * For as long as the tracer isn't disabled another entity can't
264 	 * change its status.  As such we can read the status here without
265 	 * fearing it will change under us.
266 	 */
267 	if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
268 		spin_lock(&drvdata->spinlock);
269 		stm_disable_hw(drvdata);
270 		spin_unlock(&drvdata->spinlock);
271 
272 		/* Wait until the engine has completely stopped */
273 		coresight_timeout(drvdata->base, STMTCSR, STMTCSR_BUSY_BIT, 0);
274 
275 		pm_runtime_put(csdev->dev.parent);
276 
277 		local_set(&drvdata->mode, CS_MODE_DISABLED);
278 		dev_dbg(&csdev->dev, "STM tracing disabled\n");
279 	}
280 }
281 
282 static int stm_trace_id(struct coresight_device *csdev)
283 {
284 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
285 
286 	return drvdata->traceid;
287 }
288 
289 static const struct coresight_ops_source stm_source_ops = {
290 	.trace_id	= stm_trace_id,
291 	.enable		= stm_enable,
292 	.disable	= stm_disable,
293 };
294 
295 static const struct coresight_ops stm_cs_ops = {
296 	.source_ops	= &stm_source_ops,
297 };
298 
299 static inline bool stm_addr_unaligned(const void *addr, u8 write_bytes)
300 {
301 	return ((unsigned long)addr & (write_bytes - 1));
302 }
303 
304 static void stm_send(void __iomem *addr, const void *data,
305 		     u32 size, u8 write_bytes)
306 {
307 	u8 paload[8];
308 
309 	if (stm_addr_unaligned(data, write_bytes)) {
310 		memcpy(paload, data, size);
311 		data = paload;
312 	}
313 
314 	/* now we are 64bit/32bit aligned */
315 	switch (size) {
316 #ifdef CONFIG_64BIT
317 	case 8:
318 		writeq_relaxed(*(u64 *)data, addr);
319 		break;
320 #endif
321 	case 4:
322 		writel_relaxed(*(u32 *)data, addr);
323 		break;
324 	case 2:
325 		writew_relaxed(*(u16 *)data, addr);
326 		break;
327 	case 1:
328 		writeb_relaxed(*(u8 *)data, addr);
329 		break;
330 	default:
331 		break;
332 	}
333 }
334 
335 static int stm_generic_link(struct stm_data *stm_data,
336 			    unsigned int master,  unsigned int channel)
337 {
338 	struct stm_drvdata *drvdata = container_of(stm_data,
339 						   struct stm_drvdata, stm);
340 	if (!drvdata || !drvdata->csdev)
341 		return -EINVAL;
342 
343 	return coresight_enable(drvdata->csdev);
344 }
345 
346 static void stm_generic_unlink(struct stm_data *stm_data,
347 			       unsigned int master,  unsigned int channel)
348 {
349 	struct stm_drvdata *drvdata = container_of(stm_data,
350 						   struct stm_drvdata, stm);
351 	if (!drvdata || !drvdata->csdev)
352 		return;
353 
354 	coresight_disable(drvdata->csdev);
355 }
356 
357 static phys_addr_t
358 stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
359 	      unsigned int channel, unsigned int nr_chans)
360 {
361 	struct stm_drvdata *drvdata = container_of(stm_data,
362 						   struct stm_drvdata, stm);
363 	phys_addr_t addr;
364 
365 	addr = drvdata->chs.phys + channel * BYTES_PER_CHANNEL;
366 
367 	if (offset_in_page(addr) ||
368 	    offset_in_page(nr_chans * BYTES_PER_CHANNEL))
369 		return 0;
370 
371 	return addr;
372 }
373 
374 static long stm_generic_set_options(struct stm_data *stm_data,
375 				    unsigned int master,
376 				    unsigned int channel,
377 				    unsigned int nr_chans,
378 				    unsigned long options)
379 {
380 	struct stm_drvdata *drvdata = container_of(stm_data,
381 						   struct stm_drvdata, stm);
382 	if (!(drvdata && local_read(&drvdata->mode)))
383 		return -EINVAL;
384 
385 	if (channel >= drvdata->numsp)
386 		return -EINVAL;
387 
388 	switch (options) {
389 	case STM_OPTION_GUARANTEED:
390 		set_bit(channel, drvdata->chs.guaranteed);
391 		break;
392 
393 	case STM_OPTION_INVARIANT:
394 		clear_bit(channel, drvdata->chs.guaranteed);
395 		break;
396 
397 	default:
398 		return -EINVAL;
399 	}
400 
401 	return 0;
402 }
403 
404 static ssize_t notrace stm_generic_packet(struct stm_data *stm_data,
405 				  unsigned int master,
406 				  unsigned int channel,
407 				  unsigned int packet,
408 				  unsigned int flags,
409 				  unsigned int size,
410 				  const unsigned char *payload)
411 {
412 	void __iomem *ch_addr;
413 	struct stm_drvdata *drvdata = container_of(stm_data,
414 						   struct stm_drvdata, stm);
415 	unsigned int stm_flags;
416 
417 	if (!(drvdata && local_read(&drvdata->mode)))
418 		return -EACCES;
419 
420 	if (channel >= drvdata->numsp)
421 		return -EINVAL;
422 
423 	ch_addr = stm_channel_addr(drvdata, channel);
424 
425 	stm_flags = (flags & STP_PACKET_TIMESTAMPED) ?
426 			STM_FLAG_TIMESTAMPED : 0;
427 	stm_flags |= test_bit(channel, drvdata->chs.guaranteed) ?
428 			   STM_FLAG_GUARANTEED : 0;
429 
430 	if (size > drvdata->write_bytes)
431 		size = drvdata->write_bytes;
432 	else
433 		size = rounddown_pow_of_two(size);
434 
435 	switch (packet) {
436 	case STP_PACKET_FLAG:
437 		ch_addr += stm_channel_off(STM_PKT_TYPE_FLAG, stm_flags);
438 
439 		/*
440 		 * The generic STM core sets a size of '0' on flag packets.
441 		 * As such send a flag packet of size '1' and tell the
442 		 * core we did so.
443 		 */
444 		stm_send(ch_addr, payload, 1, drvdata->write_bytes);
445 		size = 1;
446 		break;
447 
448 	case STP_PACKET_DATA:
449 		stm_flags |= (flags & STP_PACKET_MARKED) ? STM_FLAG_MARKED : 0;
450 		ch_addr += stm_channel_off(STM_PKT_TYPE_DATA, stm_flags);
451 		stm_send(ch_addr, payload, size,
452 				drvdata->write_bytes);
453 		break;
454 
455 	default:
456 		return -ENOTSUPP;
457 	}
458 
459 	return size;
460 }
461 
462 static ssize_t hwevent_enable_show(struct device *dev,
463 				   struct device_attribute *attr, char *buf)
464 {
465 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
466 	unsigned long val = drvdata->stmheer;
467 
468 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
469 }
470 
471 static ssize_t hwevent_enable_store(struct device *dev,
472 				    struct device_attribute *attr,
473 				    const char *buf, size_t size)
474 {
475 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
476 	unsigned long val;
477 	int ret = 0;
478 
479 	ret = kstrtoul(buf, 16, &val);
480 	if (ret)
481 		return -EINVAL;
482 
483 	drvdata->stmheer = val;
484 	/* HW event enable and trigger go hand in hand */
485 	drvdata->stmheter = val;
486 
487 	return size;
488 }
489 static DEVICE_ATTR_RW(hwevent_enable);
490 
491 static ssize_t hwevent_select_show(struct device *dev,
492 				   struct device_attribute *attr, char *buf)
493 {
494 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
495 	unsigned long val = drvdata->stmhebsr;
496 
497 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
498 }
499 
500 static ssize_t hwevent_select_store(struct device *dev,
501 				    struct device_attribute *attr,
502 				    const char *buf, size_t size)
503 {
504 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
505 	unsigned long val;
506 	int ret = 0;
507 
508 	ret = kstrtoul(buf, 16, &val);
509 	if (ret)
510 		return -EINVAL;
511 
512 	drvdata->stmhebsr = val;
513 
514 	return size;
515 }
516 static DEVICE_ATTR_RW(hwevent_select);
517 
518 static ssize_t port_select_show(struct device *dev,
519 				struct device_attribute *attr, char *buf)
520 {
521 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
522 	unsigned long val;
523 
524 	if (!local_read(&drvdata->mode)) {
525 		val = drvdata->stmspscr;
526 	} else {
527 		spin_lock(&drvdata->spinlock);
528 		val = readl_relaxed(drvdata->base + STMSPSCR);
529 		spin_unlock(&drvdata->spinlock);
530 	}
531 
532 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
533 }
534 
535 static ssize_t port_select_store(struct device *dev,
536 				 struct device_attribute *attr,
537 				 const char *buf, size_t size)
538 {
539 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
540 	unsigned long val, stmsper;
541 	int ret = 0;
542 
543 	ret = kstrtoul(buf, 16, &val);
544 	if (ret)
545 		return ret;
546 
547 	spin_lock(&drvdata->spinlock);
548 	drvdata->stmspscr = val;
549 
550 	if (local_read(&drvdata->mode)) {
551 		CS_UNLOCK(drvdata->base);
552 		/* Process as per ARM's TRM recommendation */
553 		stmsper = readl_relaxed(drvdata->base + STMSPER);
554 		writel_relaxed(0x0, drvdata->base + STMSPER);
555 		writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
556 		writel_relaxed(stmsper, drvdata->base + STMSPER);
557 		CS_LOCK(drvdata->base);
558 	}
559 	spin_unlock(&drvdata->spinlock);
560 
561 	return size;
562 }
563 static DEVICE_ATTR_RW(port_select);
564 
565 static ssize_t port_enable_show(struct device *dev,
566 				struct device_attribute *attr, char *buf)
567 {
568 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
569 	unsigned long val;
570 
571 	if (!local_read(&drvdata->mode)) {
572 		val = drvdata->stmsper;
573 	} else {
574 		spin_lock(&drvdata->spinlock);
575 		val = readl_relaxed(drvdata->base + STMSPER);
576 		spin_unlock(&drvdata->spinlock);
577 	}
578 
579 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
580 }
581 
582 static ssize_t port_enable_store(struct device *dev,
583 				 struct device_attribute *attr,
584 				 const char *buf, size_t size)
585 {
586 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
587 	unsigned long val;
588 	int ret = 0;
589 
590 	ret = kstrtoul(buf, 16, &val);
591 	if (ret)
592 		return ret;
593 
594 	spin_lock(&drvdata->spinlock);
595 	drvdata->stmsper = val;
596 
597 	if (local_read(&drvdata->mode)) {
598 		CS_UNLOCK(drvdata->base);
599 		writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
600 		CS_LOCK(drvdata->base);
601 	}
602 	spin_unlock(&drvdata->spinlock);
603 
604 	return size;
605 }
606 static DEVICE_ATTR_RW(port_enable);
607 
608 static ssize_t traceid_show(struct device *dev,
609 			    struct device_attribute *attr, char *buf)
610 {
611 	unsigned long val;
612 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
613 
614 	val = drvdata->traceid;
615 	return sprintf(buf, "%#lx\n", val);
616 }
617 
618 static ssize_t traceid_store(struct device *dev,
619 			     struct device_attribute *attr,
620 			     const char *buf, size_t size)
621 {
622 	int ret;
623 	unsigned long val;
624 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
625 
626 	ret = kstrtoul(buf, 16, &val);
627 	if (ret)
628 		return ret;
629 
630 	/* traceid field is 7bit wide on STM32 */
631 	drvdata->traceid = val & 0x7f;
632 	return size;
633 }
634 static DEVICE_ATTR_RW(traceid);
635 
636 #define coresight_stm_reg(name, offset)	\
637 	coresight_simple_reg32(struct stm_drvdata, name, offset)
638 
639 coresight_stm_reg(tcsr, STMTCSR);
640 coresight_stm_reg(tsfreqr, STMTSFREQR);
641 coresight_stm_reg(syncr, STMSYNCR);
642 coresight_stm_reg(sper, STMSPER);
643 coresight_stm_reg(spter, STMSPTER);
644 coresight_stm_reg(privmaskr, STMPRIVMASKR);
645 coresight_stm_reg(spscr, STMSPSCR);
646 coresight_stm_reg(spmscr, STMSPMSCR);
647 coresight_stm_reg(spfeat1r, STMSPFEAT1R);
648 coresight_stm_reg(spfeat2r, STMSPFEAT2R);
649 coresight_stm_reg(spfeat3r, STMSPFEAT3R);
650 coresight_stm_reg(devid, CORESIGHT_DEVID);
651 
652 static struct attribute *coresight_stm_attrs[] = {
653 	&dev_attr_hwevent_enable.attr,
654 	&dev_attr_hwevent_select.attr,
655 	&dev_attr_port_enable.attr,
656 	&dev_attr_port_select.attr,
657 	&dev_attr_traceid.attr,
658 	NULL,
659 };
660 
661 static struct attribute *coresight_stm_mgmt_attrs[] = {
662 	&dev_attr_tcsr.attr,
663 	&dev_attr_tsfreqr.attr,
664 	&dev_attr_syncr.attr,
665 	&dev_attr_sper.attr,
666 	&dev_attr_spter.attr,
667 	&dev_attr_privmaskr.attr,
668 	&dev_attr_spscr.attr,
669 	&dev_attr_spmscr.attr,
670 	&dev_attr_spfeat1r.attr,
671 	&dev_attr_spfeat2r.attr,
672 	&dev_attr_spfeat3r.attr,
673 	&dev_attr_devid.attr,
674 	NULL,
675 };
676 
677 static const struct attribute_group coresight_stm_group = {
678 	.attrs = coresight_stm_attrs,
679 };
680 
681 static const struct attribute_group coresight_stm_mgmt_group = {
682 	.attrs = coresight_stm_mgmt_attrs,
683 	.name = "mgmt",
684 };
685 
686 static const struct attribute_group *coresight_stm_groups[] = {
687 	&coresight_stm_group,
688 	&coresight_stm_mgmt_group,
689 	NULL,
690 };
691 
692 #ifdef CONFIG_OF
693 static int of_stm_get_stimulus_area(struct device *dev, struct resource *res)
694 {
695 	const char *name = NULL;
696 	int index = 0, found = 0;
697 	struct device_node *np = dev->of_node;
698 
699 	while (!of_property_read_string_index(np, "reg-names", index, &name)) {
700 		if (strcmp("stm-stimulus-base", name)) {
701 			index++;
702 			continue;
703 		}
704 
705 		/* We have a match and @index is where it's at */
706 		found = 1;
707 		break;
708 	}
709 
710 	if (!found)
711 		return -EINVAL;
712 
713 	return of_address_to_resource(np, index, res);
714 }
715 #else
716 static inline int of_stm_get_stimulus_area(struct device *dev,
717 					   struct resource *res)
718 {
719 	return -ENOENT;
720 }
721 #endif
722 
723 #ifdef CONFIG_ACPI
724 static int acpi_stm_get_stimulus_area(struct device *dev, struct resource *res)
725 {
726 	int rc;
727 	bool found_base = false;
728 	struct resource_entry *rent;
729 	LIST_HEAD(res_list);
730 
731 	struct acpi_device *adev = ACPI_COMPANION(dev);
732 
733 	rc = acpi_dev_get_resources(adev, &res_list, NULL, NULL);
734 	if (rc < 0)
735 		return rc;
736 
737 	/*
738 	 * The stimulus base for STM device must be listed as the second memory
739 	 * resource, followed by the programming base address as described in
740 	 * "Section 2.3 Resources" in ACPI for CoreSightTM 1.0 Platform Design
741 	 * document (DEN0067).
742 	 */
743 	rc = -ENOENT;
744 	list_for_each_entry(rent, &res_list, node) {
745 		if (resource_type(rent->res) != IORESOURCE_MEM)
746 			continue;
747 		if (found_base) {
748 			*res = *rent->res;
749 			rc = 0;
750 			break;
751 		}
752 
753 		found_base = true;
754 	}
755 
756 	acpi_dev_free_resource_list(&res_list);
757 	return rc;
758 }
759 #else
760 static inline int acpi_stm_get_stimulus_area(struct device *dev,
761 					     struct resource *res)
762 {
763 	return -ENOENT;
764 }
765 #endif
766 
767 static int stm_get_stimulus_area(struct device *dev, struct resource *res)
768 {
769 	struct fwnode_handle *fwnode = dev_fwnode(dev);
770 
771 	if (is_of_node(fwnode))
772 		return of_stm_get_stimulus_area(dev, res);
773 	else if (is_acpi_node(fwnode))
774 		return acpi_stm_get_stimulus_area(dev, res);
775 	return -ENOENT;
776 }
777 
778 static u32 stm_fundamental_data_size(struct stm_drvdata *drvdata)
779 {
780 	u32 stmspfeat2r;
781 
782 	if (!IS_ENABLED(CONFIG_64BIT))
783 		return 4;
784 
785 	stmspfeat2r = readl_relaxed(drvdata->base + STMSPFEAT2R);
786 
787 	/*
788 	 * bit[15:12] represents the fundamental data size
789 	 * 0 - 32-bit data
790 	 * 1 - 64-bit data
791 	 */
792 	return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
793 }
794 
795 static u32 stm_num_stimulus_port(struct stm_drvdata *drvdata)
796 {
797 	u32 numsp;
798 
799 	numsp = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
800 	/*
801 	 * NUMPS in STMDEVID is 17 bit long and if equal to 0x0,
802 	 * 32 stimulus ports are supported.
803 	 */
804 	numsp &= 0x1ffff;
805 	if (!numsp)
806 		numsp = STM_32_CHANNEL;
807 	return numsp;
808 }
809 
810 static void stm_init_default_data(struct stm_drvdata *drvdata)
811 {
812 	/* Don't use port selection */
813 	drvdata->stmspscr = 0x0;
814 	/*
815 	 * Enable all channel regardless of their number.  When port
816 	 * selection isn't used (see above) STMSPER applies to all
817 	 * 32 channel group available, hence setting all 32 bits to 1
818 	 */
819 	drvdata->stmsper = ~0x0;
820 
821 	/*
822 	 * The trace ID value for *ETM* tracers start at CPU_ID * 2 + 0x10 and
823 	 * anything equal to or higher than 0x70 is reserved.  Since 0x00 is
824 	 * also reserved the STM trace ID needs to be higher than 0x00 and
825 	 * lowner than 0x10.
826 	 */
827 	drvdata->traceid = 0x1;
828 
829 	/* Set invariant transaction timing on all channels */
830 	bitmap_clear(drvdata->chs.guaranteed, 0, drvdata->numsp);
831 }
832 
833 static void stm_init_generic_data(struct stm_drvdata *drvdata,
834 				  const char *name)
835 {
836 	drvdata->stm.name = name;
837 
838 	/*
839 	 * MasterIDs are assigned at HW design phase. As such the core is
840 	 * using a single master for interaction with this device.
841 	 */
842 	drvdata->stm.sw_start = 1;
843 	drvdata->stm.sw_end = 1;
844 	drvdata->stm.hw_override = true;
845 	drvdata->stm.sw_nchannels = drvdata->numsp;
846 	drvdata->stm.sw_mmiosz = BYTES_PER_CHANNEL;
847 	drvdata->stm.packet = stm_generic_packet;
848 	drvdata->stm.mmio_addr = stm_mmio_addr;
849 	drvdata->stm.link = stm_generic_link;
850 	drvdata->stm.unlink = stm_generic_unlink;
851 	drvdata->stm.set_options = stm_generic_set_options;
852 }
853 
854 static int stm_probe(struct amba_device *adev, const struct amba_id *id)
855 {
856 	int ret;
857 	void __iomem *base;
858 	unsigned long *guaranteed;
859 	struct device *dev = &adev->dev;
860 	struct coresight_platform_data *pdata = NULL;
861 	struct stm_drvdata *drvdata;
862 	struct resource *res = &adev->res;
863 	struct resource ch_res;
864 	size_t bitmap_size;
865 	struct coresight_desc desc = { 0 };
866 
867 	desc.name = coresight_alloc_device_name(&stm_devs, dev);
868 	if (!desc.name)
869 		return -ENOMEM;
870 
871 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
872 	if (!drvdata)
873 		return -ENOMEM;
874 
875 	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
876 	if (!IS_ERR(drvdata->atclk)) {
877 		ret = clk_prepare_enable(drvdata->atclk);
878 		if (ret)
879 			return ret;
880 	}
881 	dev_set_drvdata(dev, drvdata);
882 
883 	base = devm_ioremap_resource(dev, res);
884 	if (IS_ERR(base))
885 		return PTR_ERR(base);
886 	drvdata->base = base;
887 
888 	ret = stm_get_stimulus_area(dev, &ch_res);
889 	if (ret)
890 		return ret;
891 	drvdata->chs.phys = ch_res.start;
892 
893 	base = devm_ioremap_resource(dev, &ch_res);
894 	if (IS_ERR(base))
895 		return PTR_ERR(base);
896 	drvdata->chs.base = base;
897 
898 	drvdata->write_bytes = stm_fundamental_data_size(drvdata);
899 
900 	if (boot_nr_channel)
901 		drvdata->numsp = boot_nr_channel;
902 	else
903 		drvdata->numsp = stm_num_stimulus_port(drvdata);
904 
905 	bitmap_size = BITS_TO_LONGS(drvdata->numsp) * sizeof(long);
906 
907 	guaranteed = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
908 	if (!guaranteed)
909 		return -ENOMEM;
910 	drvdata->chs.guaranteed = guaranteed;
911 
912 	spin_lock_init(&drvdata->spinlock);
913 
914 	stm_init_default_data(drvdata);
915 	stm_init_generic_data(drvdata, desc.name);
916 
917 	if (stm_register_device(dev, &drvdata->stm, THIS_MODULE)) {
918 		dev_info(dev,
919 			 "%s : stm_register_device failed, probing deferred\n",
920 			 desc.name);
921 		return -EPROBE_DEFER;
922 	}
923 
924 	pdata = coresight_get_platform_data(dev);
925 	if (IS_ERR(pdata)) {
926 		ret = PTR_ERR(pdata);
927 		goto stm_unregister;
928 	}
929 	adev->dev.platform_data = pdata;
930 
931 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
932 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE;
933 	desc.ops = &stm_cs_ops;
934 	desc.pdata = pdata;
935 	desc.dev = dev;
936 	desc.groups = coresight_stm_groups;
937 	drvdata->csdev = coresight_register(&desc);
938 	if (IS_ERR(drvdata->csdev)) {
939 		ret = PTR_ERR(drvdata->csdev);
940 		goto stm_unregister;
941 	}
942 
943 	pm_runtime_put(&adev->dev);
944 
945 	dev_info(&drvdata->csdev->dev, "%s initialized\n",
946 		 (char *)coresight_get_uci_data(id));
947 	return 0;
948 
949 stm_unregister:
950 	stm_unregister_device(&drvdata->stm);
951 	return ret;
952 }
953 
954 static void stm_remove(struct amba_device *adev)
955 {
956 	struct stm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
957 
958 	coresight_unregister(drvdata->csdev);
959 
960 	stm_unregister_device(&drvdata->stm);
961 }
962 
963 #ifdef CONFIG_PM
964 static int stm_runtime_suspend(struct device *dev)
965 {
966 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
967 
968 	if (drvdata && !IS_ERR(drvdata->atclk))
969 		clk_disable_unprepare(drvdata->atclk);
970 
971 	return 0;
972 }
973 
974 static int stm_runtime_resume(struct device *dev)
975 {
976 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
977 
978 	if (drvdata && !IS_ERR(drvdata->atclk))
979 		clk_prepare_enable(drvdata->atclk);
980 
981 	return 0;
982 }
983 #endif
984 
985 static const struct dev_pm_ops stm_dev_pm_ops = {
986 	SET_RUNTIME_PM_OPS(stm_runtime_suspend, stm_runtime_resume, NULL)
987 };
988 
989 static const struct amba_id stm_ids[] = {
990 	CS_AMBA_ID_DATA(0x000bb962, "STM32"),
991 	CS_AMBA_ID_DATA(0x000bb963, "STM500"),
992 	{ 0, 0},
993 };
994 
995 MODULE_DEVICE_TABLE(amba, stm_ids);
996 
997 static struct amba_driver stm_driver = {
998 	.drv = {
999 		.name   = "coresight-stm",
1000 		.owner	= THIS_MODULE,
1001 		.pm	= &stm_dev_pm_ops,
1002 		.suppress_bind_attrs = true,
1003 	},
1004 	.probe          = stm_probe,
1005 	.remove         = stm_remove,
1006 	.id_table	= stm_ids,
1007 };
1008 
1009 module_amba_driver(stm_driver);
1010 
1011 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
1012 MODULE_DESCRIPTION("Arm CoreSight System Trace Macrocell driver");
1013 MODULE_LICENSE("GPL v2");
1014