xref: /linux/drivers/hwtracing/coresight/coresight-stm.c (revision 45d8b572fac3aa8b49d53c946b3685eaf78a2824)
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 #include "coresight-trace-id.h"
35 
36 #define STMDMASTARTR			0xc04
37 #define STMDMASTOPR			0xc08
38 #define STMDMASTATR			0xc0c
39 #define STMDMACTLR			0xc10
40 #define STMDMAIDR			0xcfc
41 #define STMHEER				0xd00
42 #define STMHETER			0xd20
43 #define STMHEBSR			0xd60
44 #define STMHEMCR			0xd64
45 #define STMHEMASTR			0xdf4
46 #define STMHEFEAT1R			0xdf8
47 #define STMHEIDR			0xdfc
48 #define STMSPER				0xe00
49 #define STMSPTER			0xe20
50 #define STMPRIVMASKR			0xe40
51 #define STMSPSCR			0xe60
52 #define STMSPMSCR			0xe64
53 #define STMSPOVERRIDER			0xe68
54 #define STMSPMOVERRIDER			0xe6c
55 #define STMSPTRIGCSR			0xe70
56 #define STMTCSR				0xe80
57 #define STMTSSTIMR			0xe84
58 #define STMTSFREQR			0xe8c
59 #define STMSYNCR			0xe90
60 #define STMAUXCR			0xe94
61 #define STMSPFEAT1R			0xea0
62 #define STMSPFEAT2R			0xea4
63 #define STMSPFEAT3R			0xea8
64 #define STMITTRIGGER			0xee8
65 #define STMITATBDATA0			0xeec
66 #define STMITATBCTR2			0xef0
67 #define STMITATBID			0xef4
68 #define STMITATBCTR0			0xef8
69 
70 #define STM_32_CHANNEL			32
71 #define BYTES_PER_CHANNEL		256
72 #define STM_TRACE_BUF_SIZE		4096
73 #define STM_SW_MASTER_END		127
74 
75 /* Register bit definition */
76 #define STMTCSR_BUSY_BIT		23
77 /* Reserve the first 10 channels for kernel usage */
78 #define STM_CHANNEL_OFFSET		0
79 
80 enum stm_pkt_type {
81 	STM_PKT_TYPE_DATA	= 0x98,
82 	STM_PKT_TYPE_FLAG	= 0xE8,
83 	STM_PKT_TYPE_TRIG	= 0xF8,
84 };
85 
86 #define stm_channel_addr(drvdata, ch)	(drvdata->chs.base +	\
87 					(ch * BYTES_PER_CHANNEL))
88 #define stm_channel_off(type, opts)	(type & ~opts)
89 
90 static int boot_nr_channel;
91 
92 /*
93  * Not really modular but using module_param is the easiest way to
94  * remain consistent with existing use cases for now.
95  */
96 module_param_named(
97 	boot_nr_channel, boot_nr_channel, int, S_IRUGO
98 );
99 
100 /*
101  * struct channel_space - central management entity for extended ports
102  * @base:		memory mapped base address where channels start.
103  * @phys:		physical base address of channel region.
104  * @guaraneed:		is the channel delivery guaranteed.
105  */
106 struct channel_space {
107 	void __iomem		*base;
108 	phys_addr_t		phys;
109 	unsigned long		*guaranteed;
110 };
111 
112 DEFINE_CORESIGHT_DEVLIST(stm_devs, "stm");
113 
114 /**
115  * struct stm_drvdata - specifics associated to an STM component
116  * @base:		memory mapped base address for this component.
117  * @atclk:		optional clock for the core parts of the STM.
118  * @csdev:		component vitals needed by the framework.
119  * @spinlock:		only one at a time pls.
120  * @chs:		the channels accociated to this STM.
121  * @stm:		structure associated to the generic STM interface.
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 	u8			traceid;
139 	u32			write_bytes;
140 	u32			stmsper;
141 	u32			stmspscr;
142 	u32			numsp;
143 	u32			stmheer;
144 	u32			stmheter;
145 	u32			stmhebsr;
146 };
147 
148 static void stm_hwevent_enable_hw(struct stm_drvdata *drvdata)
149 {
150 	CS_UNLOCK(drvdata->base);
151 
152 	writel_relaxed(drvdata->stmhebsr, drvdata->base + STMHEBSR);
153 	writel_relaxed(drvdata->stmheter, drvdata->base + STMHETER);
154 	writel_relaxed(drvdata->stmheer, drvdata->base + STMHEER);
155 	writel_relaxed(0x01 |	/* Enable HW event tracing */
156 		       0x04,	/* Error detection on event tracing */
157 		       drvdata->base + STMHEMCR);
158 
159 	CS_LOCK(drvdata->base);
160 }
161 
162 static void stm_port_enable_hw(struct stm_drvdata *drvdata)
163 {
164 	CS_UNLOCK(drvdata->base);
165 	/* ATB trigger enable on direct writes to TRIG locations */
166 	writel_relaxed(0x10,
167 		       drvdata->base + STMSPTRIGCSR);
168 	writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
169 	writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
170 
171 	CS_LOCK(drvdata->base);
172 }
173 
174 static void stm_enable_hw(struct stm_drvdata *drvdata)
175 {
176 	if (drvdata->stmheer)
177 		stm_hwevent_enable_hw(drvdata);
178 
179 	stm_port_enable_hw(drvdata);
180 
181 	CS_UNLOCK(drvdata->base);
182 
183 	/* 4096 byte between synchronisation packets */
184 	writel_relaxed(0xFFF, drvdata->base + STMSYNCR);
185 	writel_relaxed((drvdata->traceid << 16 | /* trace id */
186 			0x02 |			 /* timestamp enable */
187 			0x01),			 /* global STM enable */
188 			drvdata->base + STMTCSR);
189 
190 	CS_LOCK(drvdata->base);
191 }
192 
193 static int stm_enable(struct coresight_device *csdev, struct perf_event *event,
194 		      enum cs_mode mode)
195 {
196 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
197 
198 	if (mode != CS_MODE_SYSFS)
199 		return -EINVAL;
200 
201 	if (!coresight_take_mode(csdev, mode)) {
202 		/* Someone is already using the tracer */
203 		return -EBUSY;
204 	}
205 
206 	pm_runtime_get_sync(csdev->dev.parent);
207 
208 	spin_lock(&drvdata->spinlock);
209 	stm_enable_hw(drvdata);
210 	spin_unlock(&drvdata->spinlock);
211 
212 	dev_dbg(&csdev->dev, "STM tracing enabled\n");
213 	return 0;
214 }
215 
216 static void stm_hwevent_disable_hw(struct stm_drvdata *drvdata)
217 {
218 	CS_UNLOCK(drvdata->base);
219 
220 	writel_relaxed(0x0, drvdata->base + STMHEMCR);
221 	writel_relaxed(0x0, drvdata->base + STMHEER);
222 	writel_relaxed(0x0, drvdata->base + STMHETER);
223 
224 	CS_LOCK(drvdata->base);
225 }
226 
227 static void stm_port_disable_hw(struct stm_drvdata *drvdata)
228 {
229 	CS_UNLOCK(drvdata->base);
230 
231 	writel_relaxed(0x0, drvdata->base + STMSPER);
232 	writel_relaxed(0x0, drvdata->base + STMSPTRIGCSR);
233 
234 	CS_LOCK(drvdata->base);
235 }
236 
237 static void stm_disable_hw(struct stm_drvdata *drvdata)
238 {
239 	u32 val;
240 
241 	CS_UNLOCK(drvdata->base);
242 
243 	val = readl_relaxed(drvdata->base + STMTCSR);
244 	val &= ~0x1; /* clear global STM enable [0] */
245 	writel_relaxed(val, drvdata->base + STMTCSR);
246 
247 	CS_LOCK(drvdata->base);
248 
249 	stm_port_disable_hw(drvdata);
250 	if (drvdata->stmheer)
251 		stm_hwevent_disable_hw(drvdata);
252 }
253 
254 static void stm_disable(struct coresight_device *csdev,
255 			struct perf_event *event)
256 {
257 	struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
258 	struct csdev_access *csa = &csdev->access;
259 
260 	/*
261 	 * For as long as the tracer isn't disabled another entity can't
262 	 * change its status.  As such we can read the status here without
263 	 * fearing it will change under us.
264 	 */
265 	if (coresight_get_mode(csdev) == CS_MODE_SYSFS) {
266 		spin_lock(&drvdata->spinlock);
267 		stm_disable_hw(drvdata);
268 		spin_unlock(&drvdata->spinlock);
269 
270 		/* Wait until the engine has completely stopped */
271 		coresight_timeout(csa, STMTCSR, STMTCSR_BUSY_BIT, 0);
272 
273 		pm_runtime_put(csdev->dev.parent);
274 
275 		coresight_set_mode(csdev, CS_MODE_DISABLED);
276 		dev_dbg(&csdev->dev, "STM tracing disabled\n");
277 	}
278 }
279 
280 static const struct coresight_ops_source stm_source_ops = {
281 	.enable		= stm_enable,
282 	.disable	= stm_disable,
283 };
284 
285 static const struct coresight_ops stm_cs_ops = {
286 	.source_ops	= &stm_source_ops,
287 };
288 
289 static inline bool stm_addr_unaligned(const void *addr, u8 write_bytes)
290 {
291 	return ((unsigned long)addr & (write_bytes - 1));
292 }
293 
294 static void stm_send(void __iomem *addr, const void *data,
295 		     u32 size, u8 write_bytes)
296 {
297 	u8 paload[8];
298 
299 	if (stm_addr_unaligned(data, write_bytes)) {
300 		memcpy(paload, data, size);
301 		data = paload;
302 	}
303 
304 	/* now we are 64bit/32bit aligned */
305 	switch (size) {
306 #ifdef CONFIG_64BIT
307 	case 8:
308 		writeq_relaxed(*(u64 *)data, addr);
309 		break;
310 #endif
311 	case 4:
312 		writel_relaxed(*(u32 *)data, addr);
313 		break;
314 	case 2:
315 		writew_relaxed(*(u16 *)data, addr);
316 		break;
317 	case 1:
318 		writeb_relaxed(*(u8 *)data, addr);
319 		break;
320 	default:
321 		break;
322 	}
323 }
324 
325 static int stm_generic_link(struct stm_data *stm_data,
326 			    unsigned int master,  unsigned int channel)
327 {
328 	struct stm_drvdata *drvdata = container_of(stm_data,
329 						   struct stm_drvdata, stm);
330 	if (!drvdata || !drvdata->csdev)
331 		return -EINVAL;
332 
333 	return coresight_enable_sysfs(drvdata->csdev);
334 }
335 
336 static void stm_generic_unlink(struct stm_data *stm_data,
337 			       unsigned int master,  unsigned int channel)
338 {
339 	struct stm_drvdata *drvdata = container_of(stm_data,
340 						   struct stm_drvdata, stm);
341 	if (!drvdata || !drvdata->csdev)
342 		return;
343 
344 	coresight_disable_sysfs(drvdata->csdev);
345 }
346 
347 static phys_addr_t
348 stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
349 	      unsigned int channel, unsigned int nr_chans)
350 {
351 	struct stm_drvdata *drvdata = container_of(stm_data,
352 						   struct stm_drvdata, stm);
353 	phys_addr_t addr;
354 
355 	addr = drvdata->chs.phys + channel * BYTES_PER_CHANNEL;
356 
357 	if (offset_in_page(addr) ||
358 	    offset_in_page(nr_chans * BYTES_PER_CHANNEL))
359 		return 0;
360 
361 	return addr;
362 }
363 
364 static long stm_generic_set_options(struct stm_data *stm_data,
365 				    unsigned int master,
366 				    unsigned int channel,
367 				    unsigned int nr_chans,
368 				    unsigned long options)
369 {
370 	struct stm_drvdata *drvdata = container_of(stm_data,
371 						   struct stm_drvdata, stm);
372 	if (!(drvdata && coresight_get_mode(drvdata->csdev)))
373 		return -EINVAL;
374 
375 	if (channel >= drvdata->numsp)
376 		return -EINVAL;
377 
378 	switch (options) {
379 	case STM_OPTION_GUARANTEED:
380 		set_bit(channel, drvdata->chs.guaranteed);
381 		break;
382 
383 	case STM_OPTION_INVARIANT:
384 		clear_bit(channel, drvdata->chs.guaranteed);
385 		break;
386 
387 	default:
388 		return -EINVAL;
389 	}
390 
391 	return 0;
392 }
393 
394 static ssize_t notrace stm_generic_packet(struct stm_data *stm_data,
395 				  unsigned int master,
396 				  unsigned int channel,
397 				  unsigned int packet,
398 				  unsigned int flags,
399 				  unsigned int size,
400 				  const unsigned char *payload)
401 {
402 	void __iomem *ch_addr;
403 	struct stm_drvdata *drvdata = container_of(stm_data,
404 						   struct stm_drvdata, stm);
405 	unsigned int stm_flags;
406 
407 	if (!(drvdata && coresight_get_mode(drvdata->csdev)))
408 		return -EACCES;
409 
410 	if (channel >= drvdata->numsp)
411 		return -EINVAL;
412 
413 	ch_addr = stm_channel_addr(drvdata, channel);
414 
415 	stm_flags = (flags & STP_PACKET_TIMESTAMPED) ?
416 			STM_FLAG_TIMESTAMPED : 0;
417 	stm_flags |= test_bit(channel, drvdata->chs.guaranteed) ?
418 			   STM_FLAG_GUARANTEED : 0;
419 
420 	if (size > drvdata->write_bytes)
421 		size = drvdata->write_bytes;
422 	else
423 		size = rounddown_pow_of_two(size);
424 
425 	switch (packet) {
426 	case STP_PACKET_FLAG:
427 		ch_addr += stm_channel_off(STM_PKT_TYPE_FLAG, stm_flags);
428 
429 		/*
430 		 * The generic STM core sets a size of '0' on flag packets.
431 		 * As such send a flag packet of size '1' and tell the
432 		 * core we did so.
433 		 */
434 		stm_send(ch_addr, payload, 1, drvdata->write_bytes);
435 		size = 1;
436 		break;
437 
438 	case STP_PACKET_DATA:
439 		stm_flags |= (flags & STP_PACKET_MARKED) ? STM_FLAG_MARKED : 0;
440 		ch_addr += stm_channel_off(STM_PKT_TYPE_DATA, stm_flags);
441 		stm_send(ch_addr, payload, size,
442 				drvdata->write_bytes);
443 		break;
444 
445 	default:
446 		return -ENOTSUPP;
447 	}
448 
449 	return size;
450 }
451 
452 static ssize_t hwevent_enable_show(struct device *dev,
453 				   struct device_attribute *attr, char *buf)
454 {
455 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
456 	unsigned long val = drvdata->stmheer;
457 
458 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
459 }
460 
461 static ssize_t hwevent_enable_store(struct device *dev,
462 				    struct device_attribute *attr,
463 				    const char *buf, size_t size)
464 {
465 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
466 	unsigned long val;
467 	int ret = 0;
468 
469 	ret = kstrtoul(buf, 16, &val);
470 	if (ret)
471 		return -EINVAL;
472 
473 	drvdata->stmheer = val;
474 	/* HW event enable and trigger go hand in hand */
475 	drvdata->stmheter = val;
476 
477 	return size;
478 }
479 static DEVICE_ATTR_RW(hwevent_enable);
480 
481 static ssize_t hwevent_select_show(struct device *dev,
482 				   struct device_attribute *attr, char *buf)
483 {
484 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
485 	unsigned long val = drvdata->stmhebsr;
486 
487 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
488 }
489 
490 static ssize_t hwevent_select_store(struct device *dev,
491 				    struct device_attribute *attr,
492 				    const char *buf, size_t size)
493 {
494 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
495 	unsigned long val;
496 	int ret = 0;
497 
498 	ret = kstrtoul(buf, 16, &val);
499 	if (ret)
500 		return -EINVAL;
501 
502 	drvdata->stmhebsr = val;
503 
504 	return size;
505 }
506 static DEVICE_ATTR_RW(hwevent_select);
507 
508 static ssize_t port_select_show(struct device *dev,
509 				struct device_attribute *attr, char *buf)
510 {
511 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
512 	unsigned long val;
513 
514 	if (!coresight_get_mode(drvdata->csdev)) {
515 		val = drvdata->stmspscr;
516 	} else {
517 		spin_lock(&drvdata->spinlock);
518 		val = readl_relaxed(drvdata->base + STMSPSCR);
519 		spin_unlock(&drvdata->spinlock);
520 	}
521 
522 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
523 }
524 
525 static ssize_t port_select_store(struct device *dev,
526 				 struct device_attribute *attr,
527 				 const char *buf, size_t size)
528 {
529 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
530 	unsigned long val, stmsper;
531 	int ret = 0;
532 
533 	ret = kstrtoul(buf, 16, &val);
534 	if (ret)
535 		return ret;
536 
537 	spin_lock(&drvdata->spinlock);
538 	drvdata->stmspscr = val;
539 
540 	if (coresight_get_mode(drvdata->csdev)) {
541 		CS_UNLOCK(drvdata->base);
542 		/* Process as per ARM's TRM recommendation */
543 		stmsper = readl_relaxed(drvdata->base + STMSPER);
544 		writel_relaxed(0x0, drvdata->base + STMSPER);
545 		writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
546 		writel_relaxed(stmsper, drvdata->base + STMSPER);
547 		CS_LOCK(drvdata->base);
548 	}
549 	spin_unlock(&drvdata->spinlock);
550 
551 	return size;
552 }
553 static DEVICE_ATTR_RW(port_select);
554 
555 static ssize_t port_enable_show(struct device *dev,
556 				struct device_attribute *attr, char *buf)
557 {
558 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
559 	unsigned long val;
560 
561 	if (!coresight_get_mode(drvdata->csdev)) {
562 		val = drvdata->stmsper;
563 	} else {
564 		spin_lock(&drvdata->spinlock);
565 		val = readl_relaxed(drvdata->base + STMSPER);
566 		spin_unlock(&drvdata->spinlock);
567 	}
568 
569 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
570 }
571 
572 static ssize_t port_enable_store(struct device *dev,
573 				 struct device_attribute *attr,
574 				 const char *buf, size_t size)
575 {
576 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
577 	unsigned long val;
578 	int ret = 0;
579 
580 	ret = kstrtoul(buf, 16, &val);
581 	if (ret)
582 		return ret;
583 
584 	spin_lock(&drvdata->spinlock);
585 	drvdata->stmsper = val;
586 
587 	if (coresight_get_mode(drvdata->csdev)) {
588 		CS_UNLOCK(drvdata->base);
589 		writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
590 		CS_LOCK(drvdata->base);
591 	}
592 	spin_unlock(&drvdata->spinlock);
593 
594 	return size;
595 }
596 static DEVICE_ATTR_RW(port_enable);
597 
598 static ssize_t traceid_show(struct device *dev,
599 			    struct device_attribute *attr, char *buf)
600 {
601 	unsigned long val;
602 	struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
603 
604 	val = drvdata->traceid;
605 	return sprintf(buf, "%#lx\n", val);
606 }
607 static DEVICE_ATTR_RO(traceid);
608 
609 static struct attribute *coresight_stm_attrs[] = {
610 	&dev_attr_hwevent_enable.attr,
611 	&dev_attr_hwevent_select.attr,
612 	&dev_attr_port_enable.attr,
613 	&dev_attr_port_select.attr,
614 	&dev_attr_traceid.attr,
615 	NULL,
616 };
617 
618 static struct attribute *coresight_stm_mgmt_attrs[] = {
619 	coresight_simple_reg32(tcsr, STMTCSR),
620 	coresight_simple_reg32(tsfreqr, STMTSFREQR),
621 	coresight_simple_reg32(syncr, STMSYNCR),
622 	coresight_simple_reg32(sper, STMSPER),
623 	coresight_simple_reg32(spter, STMSPTER),
624 	coresight_simple_reg32(privmaskr, STMPRIVMASKR),
625 	coresight_simple_reg32(spscr, STMSPSCR),
626 	coresight_simple_reg32(spmscr, STMSPMSCR),
627 	coresight_simple_reg32(spfeat1r, STMSPFEAT1R),
628 	coresight_simple_reg32(spfeat2r, STMSPFEAT2R),
629 	coresight_simple_reg32(spfeat3r, STMSPFEAT3R),
630 	coresight_simple_reg32(devid, CORESIGHT_DEVID),
631 	NULL,
632 };
633 
634 static const struct attribute_group coresight_stm_group = {
635 	.attrs = coresight_stm_attrs,
636 };
637 
638 static const struct attribute_group coresight_stm_mgmt_group = {
639 	.attrs = coresight_stm_mgmt_attrs,
640 	.name = "mgmt",
641 };
642 
643 static const struct attribute_group *coresight_stm_groups[] = {
644 	&coresight_stm_group,
645 	&coresight_stm_mgmt_group,
646 	NULL,
647 };
648 
649 #ifdef CONFIG_OF
650 static int of_stm_get_stimulus_area(struct device *dev, struct resource *res)
651 {
652 	const char *name = NULL;
653 	int index = 0, found = 0;
654 	struct device_node *np = dev->of_node;
655 
656 	while (!of_property_read_string_index(np, "reg-names", index, &name)) {
657 		if (strcmp("stm-stimulus-base", name)) {
658 			index++;
659 			continue;
660 		}
661 
662 		/* We have a match and @index is where it's at */
663 		found = 1;
664 		break;
665 	}
666 
667 	if (!found)
668 		return -EINVAL;
669 
670 	return of_address_to_resource(np, index, res);
671 }
672 #else
673 static inline int of_stm_get_stimulus_area(struct device *dev,
674 					   struct resource *res)
675 {
676 	return -ENOENT;
677 }
678 #endif
679 
680 #ifdef CONFIG_ACPI
681 static int acpi_stm_get_stimulus_area(struct device *dev, struct resource *res)
682 {
683 	int rc;
684 	bool found_base = false;
685 	struct resource_entry *rent;
686 	LIST_HEAD(res_list);
687 
688 	struct acpi_device *adev = ACPI_COMPANION(dev);
689 
690 	rc = acpi_dev_get_resources(adev, &res_list, NULL, NULL);
691 	if (rc < 0)
692 		return rc;
693 
694 	/*
695 	 * The stimulus base for STM device must be listed as the second memory
696 	 * resource, followed by the programming base address as described in
697 	 * "Section 2.3 Resources" in ACPI for CoreSightTM 1.0 Platform Design
698 	 * document (DEN0067).
699 	 */
700 	rc = -ENOENT;
701 	list_for_each_entry(rent, &res_list, node) {
702 		if (resource_type(rent->res) != IORESOURCE_MEM)
703 			continue;
704 		if (found_base) {
705 			*res = *rent->res;
706 			rc = 0;
707 			break;
708 		}
709 
710 		found_base = true;
711 	}
712 
713 	acpi_dev_free_resource_list(&res_list);
714 	return rc;
715 }
716 #else
717 static inline int acpi_stm_get_stimulus_area(struct device *dev,
718 					     struct resource *res)
719 {
720 	return -ENOENT;
721 }
722 #endif
723 
724 static int stm_get_stimulus_area(struct device *dev, struct resource *res)
725 {
726 	struct fwnode_handle *fwnode = dev_fwnode(dev);
727 
728 	if (is_of_node(fwnode))
729 		return of_stm_get_stimulus_area(dev, res);
730 	else if (is_acpi_node(fwnode))
731 		return acpi_stm_get_stimulus_area(dev, res);
732 	return -ENOENT;
733 }
734 
735 static u32 stm_fundamental_data_size(struct stm_drvdata *drvdata)
736 {
737 	u32 stmspfeat2r;
738 
739 	if (!IS_ENABLED(CONFIG_64BIT))
740 		return 4;
741 
742 	stmspfeat2r = readl_relaxed(drvdata->base + STMSPFEAT2R);
743 
744 	/*
745 	 * bit[15:12] represents the fundamental data size
746 	 * 0 - 32-bit data
747 	 * 1 - 64-bit data
748 	 */
749 	return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
750 }
751 
752 static u32 stm_num_stimulus_port(struct stm_drvdata *drvdata)
753 {
754 	u32 numsp;
755 
756 	numsp = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
757 	/*
758 	 * NUMPS in STMDEVID is 17 bit long and if equal to 0x0,
759 	 * 32 stimulus ports are supported.
760 	 */
761 	numsp &= 0x1ffff;
762 	if (!numsp)
763 		numsp = STM_32_CHANNEL;
764 	return numsp;
765 }
766 
767 static void stm_init_default_data(struct stm_drvdata *drvdata)
768 {
769 	/* Don't use port selection */
770 	drvdata->stmspscr = 0x0;
771 	/*
772 	 * Enable all channel regardless of their number.  When port
773 	 * selection isn't used (see above) STMSPER applies to all
774 	 * 32 channel group available, hence setting all 32 bits to 1
775 	 */
776 	drvdata->stmsper = ~0x0;
777 
778 	/* Set invariant transaction timing on all channels */
779 	bitmap_clear(drvdata->chs.guaranteed, 0, drvdata->numsp);
780 }
781 
782 static void stm_init_generic_data(struct stm_drvdata *drvdata,
783 				  const char *name)
784 {
785 	drvdata->stm.name = name;
786 
787 	/*
788 	 * MasterIDs are assigned at HW design phase. As such the core is
789 	 * using a single master for interaction with this device.
790 	 */
791 	drvdata->stm.sw_start = 1;
792 	drvdata->stm.sw_end = 1;
793 	drvdata->stm.hw_override = true;
794 	drvdata->stm.sw_nchannels = drvdata->numsp;
795 	drvdata->stm.sw_mmiosz = BYTES_PER_CHANNEL;
796 	drvdata->stm.packet = stm_generic_packet;
797 	drvdata->stm.mmio_addr = stm_mmio_addr;
798 	drvdata->stm.link = stm_generic_link;
799 	drvdata->stm.unlink = stm_generic_unlink;
800 	drvdata->stm.set_options = stm_generic_set_options;
801 }
802 
803 static int stm_probe(struct amba_device *adev, const struct amba_id *id)
804 {
805 	int ret, trace_id;
806 	void __iomem *base;
807 	struct device *dev = &adev->dev;
808 	struct coresight_platform_data *pdata = NULL;
809 	struct stm_drvdata *drvdata;
810 	struct resource *res = &adev->res;
811 	struct resource ch_res;
812 	struct coresight_desc desc = { 0 };
813 
814 	desc.name = coresight_alloc_device_name(&stm_devs, dev);
815 	if (!desc.name)
816 		return -ENOMEM;
817 
818 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
819 	if (!drvdata)
820 		return -ENOMEM;
821 
822 	drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
823 	if (!IS_ERR(drvdata->atclk)) {
824 		ret = clk_prepare_enable(drvdata->atclk);
825 		if (ret)
826 			return ret;
827 	}
828 	dev_set_drvdata(dev, drvdata);
829 
830 	base = devm_ioremap_resource(dev, res);
831 	if (IS_ERR(base))
832 		return PTR_ERR(base);
833 	drvdata->base = base;
834 	desc.access = CSDEV_ACCESS_IOMEM(base);
835 
836 	ret = stm_get_stimulus_area(dev, &ch_res);
837 	if (ret)
838 		return ret;
839 	drvdata->chs.phys = ch_res.start;
840 
841 	base = devm_ioremap_resource(dev, &ch_res);
842 	if (IS_ERR(base))
843 		return PTR_ERR(base);
844 	drvdata->chs.base = base;
845 
846 	drvdata->write_bytes = stm_fundamental_data_size(drvdata);
847 
848 	if (boot_nr_channel)
849 		drvdata->numsp = boot_nr_channel;
850 	else
851 		drvdata->numsp = stm_num_stimulus_port(drvdata);
852 
853 	drvdata->chs.guaranteed = devm_bitmap_zalloc(dev, drvdata->numsp,
854 						     GFP_KERNEL);
855 	if (!drvdata->chs.guaranteed)
856 		return -ENOMEM;
857 
858 	spin_lock_init(&drvdata->spinlock);
859 
860 	stm_init_default_data(drvdata);
861 	stm_init_generic_data(drvdata, desc.name);
862 
863 	if (stm_register_device(dev, &drvdata->stm, THIS_MODULE)) {
864 		dev_info(dev,
865 			 "%s : stm_register_device failed, probing deferred\n",
866 			 desc.name);
867 		return -EPROBE_DEFER;
868 	}
869 
870 	pdata = coresight_get_platform_data(dev);
871 	if (IS_ERR(pdata)) {
872 		ret = PTR_ERR(pdata);
873 		goto stm_unregister;
874 	}
875 	adev->dev.platform_data = pdata;
876 
877 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
878 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE;
879 	desc.ops = &stm_cs_ops;
880 	desc.pdata = pdata;
881 	desc.dev = dev;
882 	desc.groups = coresight_stm_groups;
883 	drvdata->csdev = coresight_register(&desc);
884 	if (IS_ERR(drvdata->csdev)) {
885 		ret = PTR_ERR(drvdata->csdev);
886 		goto stm_unregister;
887 	}
888 
889 	trace_id = coresight_trace_id_get_system_id();
890 	if (trace_id < 0) {
891 		ret = trace_id;
892 		goto cs_unregister;
893 	}
894 	drvdata->traceid = (u8)trace_id;
895 
896 	pm_runtime_put(&adev->dev);
897 
898 	dev_info(&drvdata->csdev->dev, "%s initialized\n",
899 		 (char *)coresight_get_uci_data(id));
900 	return 0;
901 
902 cs_unregister:
903 	coresight_unregister(drvdata->csdev);
904 
905 stm_unregister:
906 	stm_unregister_device(&drvdata->stm);
907 	return ret;
908 }
909 
910 static void stm_remove(struct amba_device *adev)
911 {
912 	struct stm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
913 
914 	coresight_trace_id_put_system_id(drvdata->traceid);
915 	coresight_unregister(drvdata->csdev);
916 
917 	stm_unregister_device(&drvdata->stm);
918 }
919 
920 #ifdef CONFIG_PM
921 static int stm_runtime_suspend(struct device *dev)
922 {
923 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
924 
925 	if (drvdata && !IS_ERR(drvdata->atclk))
926 		clk_disable_unprepare(drvdata->atclk);
927 
928 	return 0;
929 }
930 
931 static int stm_runtime_resume(struct device *dev)
932 {
933 	struct stm_drvdata *drvdata = dev_get_drvdata(dev);
934 
935 	if (drvdata && !IS_ERR(drvdata->atclk))
936 		clk_prepare_enable(drvdata->atclk);
937 
938 	return 0;
939 }
940 #endif
941 
942 static const struct dev_pm_ops stm_dev_pm_ops = {
943 	SET_RUNTIME_PM_OPS(stm_runtime_suspend, stm_runtime_resume, NULL)
944 };
945 
946 static const struct amba_id stm_ids[] = {
947 	CS_AMBA_ID_DATA(0x000bb962, "STM32"),
948 	CS_AMBA_ID_DATA(0x000bb963, "STM500"),
949 	{ 0, 0, NULL },
950 };
951 
952 MODULE_DEVICE_TABLE(amba, stm_ids);
953 
954 static struct amba_driver stm_driver = {
955 	.drv = {
956 		.name   = "coresight-stm",
957 		.owner	= THIS_MODULE,
958 		.pm	= &stm_dev_pm_ops,
959 		.suppress_bind_attrs = true,
960 	},
961 	.probe          = stm_probe,
962 	.remove         = stm_remove,
963 	.id_table	= stm_ids,
964 };
965 
966 module_amba_driver(stm_driver);
967 
968 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
969 MODULE_DESCRIPTION("Arm CoreSight System Trace Macrocell driver");
970 MODULE_LICENSE("GPL v2");
971