1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright(C) 2015 Linaro Limited. All rights reserved.
  4 * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
  5 */
  6
  7#include <linux/bitfield.h>
  8#include <linux/coresight.h>
  9#include <linux/coresight-pmu.h>
 10#include <linux/cpumask.h>
 11#include <linux/device.h>
 12#include <linux/list.h>
 13#include <linux/mm.h>
 14#include <linux/init.h>
 15#include <linux/perf_event.h>
 16#include <linux/percpu-defs.h>
 17#include <linux/slab.h>
 18#include <linux/stringhash.h>
 19#include <linux/types.h>
 20#include <linux/workqueue.h>
 21
 22#include "coresight-config.h"
 23#include "coresight-etm-perf.h"
 24#include "coresight-priv.h"
 25#include "coresight-syscfg.h"
 26#include "coresight-trace-id.h"
 27
 28static struct pmu etm_pmu;
 29static bool etm_perf_up;
 30
 31/*
 32 * An ETM context for a running event includes the perf aux handle
 33 * and aux_data. For ETM, the aux_data (etm_event_data), consists of
 34 * the trace path and the sink configuration. The event data is accessible
 35 * via perf_get_aux(handle). However, a sink could "end" a perf output
 36 * handle via the IRQ handler. And if the "sink" encounters a failure
 37 * to "begin" another session (e.g due to lack of space in the buffer),
 38 * the handle will be cleared. Thus, the event_data may not be accessible
 39 * from the handle when we get to the etm_event_stop(), which is required
 40 * for stopping the trace path. The event_data is guaranteed to stay alive
 41 * until "free_aux()", which cannot happen as long as the event is active on
 42 * the ETM. Thus the event_data for the session must be part of the ETM context
 43 * to make sure we can disable the trace path.
 44 */
 45struct etm_ctxt {
 46	struct perf_output_handle handle;
 47	struct etm_event_data *event_data;
 48};
 49
 50static DEFINE_PER_CPU(struct etm_ctxt, etm_ctxt);
 51static DEFINE_PER_CPU(struct coresight_device *, csdev_src);
 52
 53/*
 54 * The PMU formats were orignally for ETMv3.5/PTM's ETMCR 'config';
 55 * now take them as general formats and apply on all ETMs.
 56 */
 57PMU_FORMAT_ATTR(branch_broadcast, "config:"__stringify(ETM_OPT_BRANCH_BROADCAST));
 58PMU_FORMAT_ATTR(cycacc,		"config:" __stringify(ETM_OPT_CYCACC));
 59/* contextid1 enables tracing CONTEXTIDR_EL1 for ETMv4 */
 60PMU_FORMAT_ATTR(contextid1,	"config:" __stringify(ETM_OPT_CTXTID));
 61/* contextid2 enables tracing CONTEXTIDR_EL2 for ETMv4 */
 62PMU_FORMAT_ATTR(contextid2,	"config:" __stringify(ETM_OPT_CTXTID2));
 63PMU_FORMAT_ATTR(timestamp,	"config:" __stringify(ETM_OPT_TS));
 64PMU_FORMAT_ATTR(retstack,	"config:" __stringify(ETM_OPT_RETSTK));
 65/* preset - if sink ID is used as a configuration selector */
 66PMU_FORMAT_ATTR(preset,		"config:0-3");
 67/* Sink ID - same for all ETMs */
 68PMU_FORMAT_ATTR(sinkid,		"config2:0-31");
 69/* config ID - set if a system configuration is selected */
 70PMU_FORMAT_ATTR(configid,	"config2:32-63");
 71PMU_FORMAT_ATTR(cc_threshold,	"config3:0-11");
 72
 73
 74/*
 75 * contextid always traces the "PID".  The PID is in CONTEXTIDR_EL1
 76 * when the kernel is running at EL1; when the kernel is at EL2,
 77 * the PID is in CONTEXTIDR_EL2.
 78 */
 79static ssize_t format_attr_contextid_show(struct device *dev,
 80					  struct device_attribute *attr,
 81					  char *page)
 82{
 83	int pid_fmt = ETM_OPT_CTXTID;
 84
 85#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X)
 86	pid_fmt = is_kernel_in_hyp_mode() ? ETM_OPT_CTXTID2 : ETM_OPT_CTXTID;
 87#endif
 88	return sprintf(page, "config:%d\n", pid_fmt);
 89}
 90
 91static struct device_attribute format_attr_contextid =
 92	__ATTR(contextid, 0444, format_attr_contextid_show, NULL);
 93
 94static struct attribute *etm_config_formats_attr[] = {
 95	&format_attr_cycacc.attr,
 96	&format_attr_contextid.attr,
 97	&format_attr_contextid1.attr,
 98	&format_attr_contextid2.attr,
 99	&format_attr_timestamp.attr,
100	&format_attr_retstack.attr,
101	&format_attr_sinkid.attr,
102	&format_attr_preset.attr,
103	&format_attr_configid.attr,
104	&format_attr_branch_broadcast.attr,
105	&format_attr_cc_threshold.attr,
106	NULL,
107};
108
109static const struct attribute_group etm_pmu_format_group = {
110	.name   = "format",
111	.attrs  = etm_config_formats_attr,
112};
113
114static struct attribute *etm_config_sinks_attr[] = {
115	NULL,
116};
117
118static const struct attribute_group etm_pmu_sinks_group = {
119	.name   = "sinks",
120	.attrs  = etm_config_sinks_attr,
121};
122
123static struct attribute *etm_config_events_attr[] = {
124	NULL,
125};
126
127static const struct attribute_group etm_pmu_events_group = {
128	.name   = "events",
129	.attrs  = etm_config_events_attr,
130};
131
132static const struct attribute_group *etm_pmu_attr_groups[] = {
133	&etm_pmu_format_group,
134	&etm_pmu_sinks_group,
135	&etm_pmu_events_group,
136	NULL,
137};
138
139static inline struct list_head **
140etm_event_cpu_path_ptr(struct etm_event_data *data, int cpu)
141{
142	return per_cpu_ptr(data->path, cpu);
143}
144
145static inline struct list_head *
146etm_event_cpu_path(struct etm_event_data *data, int cpu)
147{
148	return *etm_event_cpu_path_ptr(data, cpu);
149}
150
151static void etm_event_read(struct perf_event *event) {}
152
153static int etm_addr_filters_alloc(struct perf_event *event)
154{
155	struct etm_filters *filters;
156	int node = event->cpu == -1 ? -1 : cpu_to_node(event->cpu);
157
158	filters = kzalloc_node(sizeof(struct etm_filters), GFP_KERNEL, node);
159	if (!filters)
160		return -ENOMEM;
161
162	if (event->parent)
163		memcpy(filters, event->parent->hw.addr_filters,
164		       sizeof(*filters));
165
166	event->hw.addr_filters = filters;
167
168	return 0;
169}
170
171static void etm_event_destroy(struct perf_event *event)
172{
173	kfree(event->hw.addr_filters);
174	event->hw.addr_filters = NULL;
175}
176
177static int etm_event_init(struct perf_event *event)
178{
179	int ret = 0;
180
181	if (event->attr.type != etm_pmu.type) {
182		ret = -ENOENT;
183		goto out;
184	}
185
186	ret = etm_addr_filters_alloc(event);
187	if (ret)
188		goto out;
189
190	event->destroy = etm_event_destroy;
191out:
192	return ret;
193}
194
195static void free_sink_buffer(struct etm_event_data *event_data)
196{
197	int cpu;
198	cpumask_t *mask = &event_data->mask;
199	struct coresight_device *sink;
200
201	if (!event_data->snk_config)
202		return;
203
204	if (WARN_ON(cpumask_empty(mask)))
205		return;
206
207	cpu = cpumask_first(mask);
208	sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu));
209	sink_ops(sink)->free_buffer(event_data->snk_config);
210}
211
212static void free_event_data(struct work_struct *work)
213{
214	int cpu;
215	cpumask_t *mask;
216	struct etm_event_data *event_data;
217
218	event_data = container_of(work, struct etm_event_data, work);
219	mask = &event_data->mask;
220
221	/* Free the sink buffers, if there are any */
222	free_sink_buffer(event_data);
223
224	/* clear any configuration we were using */
225	if (event_data->cfg_hash)
226		cscfg_deactivate_config(event_data->cfg_hash);
227
228	for_each_cpu(cpu, mask) {
229		struct list_head **ppath;
230
231		ppath = etm_event_cpu_path_ptr(event_data, cpu);
232		if (!(IS_ERR_OR_NULL(*ppath))) {
233			struct coresight_device *sink = coresight_get_sink(*ppath);
234
235			/*
236			 * Mark perf event as done for trace id allocator, but don't call
237			 * coresight_trace_id_put_cpu_id_map() on individual IDs. Perf sessions
238			 * never free trace IDs to ensure that the ID associated with a CPU
239			 * cannot change during their and other's concurrent sessions. Instead,
240			 * a refcount is used so that the last event to call
241			 * coresight_trace_id_perf_stop() frees all IDs.
242			 */
243			coresight_trace_id_perf_stop(&sink->perf_sink_id_map);
244
245			coresight_release_path(*ppath);
246		}
247		*ppath = NULL;
 
248	}
249
 
 
 
250	free_percpu(event_data->path);
251	kfree(event_data);
252}
253
254static void *alloc_event_data(int cpu)
255{
256	cpumask_t *mask;
257	struct etm_event_data *event_data;
258
259	/* First get memory for the session's data */
260	event_data = kzalloc(sizeof(struct etm_event_data), GFP_KERNEL);
261	if (!event_data)
262		return NULL;
263
264
265	mask = &event_data->mask;
266	if (cpu != -1)
267		cpumask_set_cpu(cpu, mask);
268	else
269		cpumask_copy(mask, cpu_present_mask);
270
271	/*
272	 * Each CPU has a single path between source and destination.  As such
273	 * allocate an array using CPU numbers as indexes.  That way a path
274	 * for any CPU can easily be accessed at any given time.  We proceed
275	 * the same way for sessions involving a single CPU.  The cost of
276	 * unused memory when dealing with single CPU trace scenarios is small
277	 * compared to the cost of searching through an optimized array.
278	 */
279	event_data->path = alloc_percpu(struct list_head *);
280
281	if (!event_data->path) {
282		kfree(event_data);
283		return NULL;
284	}
285
286	return event_data;
287}
288
289static void etm_free_aux(void *data)
290{
291	struct etm_event_data *event_data = data;
292
293	schedule_work(&event_data->work);
294}
295
296/*
297 * Check if two given sinks are compatible with each other,
298 * so that they can use the same sink buffers, when an event
299 * moves around.
300 */
301static bool sinks_compatible(struct coresight_device *a,
302			     struct coresight_device *b)
303{
304	if (!a || !b)
305		return false;
306	/*
307	 * If the sinks are of the same subtype and driven
308	 * by the same driver, we can use the same buffer
309	 * on these sinks.
310	 */
311	return (a->subtype.sink_subtype == b->subtype.sink_subtype) &&
312	       (sink_ops(a) == sink_ops(b));
313}
314
315static void *etm_setup_aux(struct perf_event *event, void **pages,
316			   int nr_pages, bool overwrite)
317{
318	u32 id, cfg_hash;
319	int cpu = event->cpu;
320	int trace_id;
321	cpumask_t *mask;
322	struct coresight_device *sink = NULL;
323	struct coresight_device *user_sink = NULL, *last_sink = NULL;
324	struct etm_event_data *event_data = NULL;
325
326	event_data = alloc_event_data(cpu);
327	if (!event_data)
328		return NULL;
329	INIT_WORK(&event_data->work, free_event_data);
330
331	/* First get the selected sink from user space. */
332	if (event->attr.config2 & GENMASK_ULL(31, 0)) {
333		id = (u32)event->attr.config2;
334		sink = user_sink = coresight_get_sink_by_id(id);
335	}
336
 
 
 
337	/* check if user wants a coresight configuration selected */
338	cfg_hash = (u32)((event->attr.config2 & GENMASK_ULL(63, 32)) >> 32);
339	if (cfg_hash) {
340		if (cscfg_activate_config(cfg_hash))
341			goto err;
342		event_data->cfg_hash = cfg_hash;
343	}
344
345	mask = &event_data->mask;
346
347	/*
348	 * Setup the path for each CPU in a trace session. We try to build
349	 * trace path for each CPU in the mask. If we don't find an ETM
350	 * for the CPU or fail to build a path, we clear the CPU from the
351	 * mask and continue with the rest. If ever we try to trace on those
352	 * CPUs, we can handle it and fail the session.
353	 */
354	for_each_cpu(cpu, mask) {
355		struct list_head *path;
356		struct coresight_device *csdev;
357
358		csdev = per_cpu(csdev_src, cpu);
359		/*
360		 * If there is no ETM associated with this CPU clear it from
361		 * the mask and continue with the rest. If ever we try to trace
362		 * on this CPU, we handle it accordingly.
363		 */
364		if (!csdev) {
365			cpumask_clear_cpu(cpu, mask);
366			continue;
367		}
368
369		/*
370		 * No sink provided - look for a default sink for all the ETMs,
371		 * where this event can be scheduled.
372		 * We allocate the sink specific buffers only once for this
373		 * event. If the ETMs have different default sink devices, we
374		 * can only use a single "type" of sink as the event can carry
375		 * only one sink specific buffer. Thus we have to make sure
376		 * that the sinks are of the same type and driven by the same
377		 * driver, as the one we allocate the buffer for. As such
378		 * we choose the first sink and check if the remaining ETMs
379		 * have a compatible default sink. We don't trace on a CPU
380		 * if the sink is not compatible.
381		 */
382		if (!user_sink) {
383			/* Find the default sink for this ETM */
384			sink = coresight_find_default_sink(csdev);
385			if (!sink) {
386				cpumask_clear_cpu(cpu, mask);
387				continue;
388			}
389
390			/* Check if this sink compatible with the last sink */
391			if (last_sink && !sinks_compatible(last_sink, sink)) {
392				cpumask_clear_cpu(cpu, mask);
393				continue;
394			}
395			last_sink = sink;
396		}
397
398		/*
399		 * Building a path doesn't enable it, it simply builds a
400		 * list of devices from source to sink that can be
401		 * referenced later when the path is actually needed.
402		 */
403		path = coresight_build_path(csdev, sink);
404		if (IS_ERR(path)) {
405			cpumask_clear_cpu(cpu, mask);
406			continue;
407		}
408
409		/* ensure we can allocate a trace ID for this CPU */
410		trace_id = coresight_trace_id_get_cpu_id_map(cpu, &sink->perf_sink_id_map);
411		if (!IS_VALID_CS_TRACE_ID(trace_id)) {
412			cpumask_clear_cpu(cpu, mask);
413			coresight_release_path(path);
414			continue;
415		}
416
417		coresight_trace_id_perf_start(&sink->perf_sink_id_map);
418		*etm_event_cpu_path_ptr(event_data, cpu) = path;
419	}
420
421	/* no sink found for any CPU - cannot trace */
422	if (!sink)
423		goto err;
424
425	/* If we don't have any CPUs ready for tracing, abort */
426	cpu = cpumask_first(mask);
427	if (cpu >= nr_cpu_ids)
428		goto err;
429
430	if (!sink_ops(sink)->alloc_buffer || !sink_ops(sink)->free_buffer)
431		goto err;
432
433	/*
434	 * Allocate the sink buffer for this session. All the sinks
435	 * where this event can be scheduled are ensured to be of the
436	 * same type. Thus the same sink configuration is used by the
437	 * sinks.
438	 */
439	event_data->snk_config =
440			sink_ops(sink)->alloc_buffer(sink, event, pages,
441						     nr_pages, overwrite);
442	if (!event_data->snk_config)
443		goto err;
444
445out:
446	return event_data;
447
448err:
449	etm_free_aux(event_data);
450	event_data = NULL;
451	goto out;
452}
453
454static void etm_event_start(struct perf_event *event, int flags)
455{
456	int cpu = smp_processor_id();
457	struct etm_event_data *event_data;
458	struct etm_ctxt *ctxt = this_cpu_ptr(&etm_ctxt);
459	struct perf_output_handle *handle = &ctxt->handle;
460	struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
461	struct list_head *path;
462	u64 hw_id;
463	u8 trace_id;
464
465	if (!csdev)
466		goto fail;
467
468	/* Have we messed up our tracking ? */
469	if (WARN_ON(ctxt->event_data))
470		goto fail;
471
472	/*
473	 * Deal with the ring buffer API and get a handle on the
474	 * session's information.
475	 */
476	event_data = perf_aux_output_begin(handle, event);
477	if (!event_data)
478		goto fail;
479
480	/*
481	 * Check if this ETM is allowed to trace, as decided
482	 * at etm_setup_aux(). This could be due to an unreachable
483	 * sink from this ETM. We can't do much in this case if
484	 * the sink was specified or hinted to the driver. For
485	 * now, simply don't record anything on this ETM.
486	 *
487	 * As such we pretend that everything is fine, and let
488	 * it continue without actually tracing. The event could
489	 * continue tracing when it moves to a CPU where it is
490	 * reachable to a sink.
491	 */
492	if (!cpumask_test_cpu(cpu, &event_data->mask))
493		goto out;
494
495	path = etm_event_cpu_path(event_data, cpu);
496	/* We need a sink, no need to continue without one */
497	sink = coresight_get_sink(path);
498	if (WARN_ON_ONCE(!sink))
499		goto fail_end_stop;
500
501	/* Nothing will happen without a path */
502	if (coresight_enable_path(path, CS_MODE_PERF, handle))
503		goto fail_end_stop;
504
505	/* Finally enable the tracer */
506	if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF,
507				      &sink->perf_sink_id_map))
508		goto fail_disable_path;
509
510	/*
511	 * output cpu / trace ID in perf record, once for the lifetime
512	 * of the event.
513	 */
514	if (!cpumask_test_cpu(cpu, &event_data->aux_hwid_done)) {
515		cpumask_set_cpu(cpu, &event_data->aux_hwid_done);
516
517		trace_id = coresight_trace_id_read_cpu_id_map(cpu, &sink->perf_sink_id_map);
518
519		hw_id = FIELD_PREP(CS_AUX_HW_ID_MAJOR_VERSION_MASK,
520				CS_AUX_HW_ID_MAJOR_VERSION);
521		hw_id |= FIELD_PREP(CS_AUX_HW_ID_MINOR_VERSION_MASK,
522				CS_AUX_HW_ID_MINOR_VERSION);
523		hw_id |= FIELD_PREP(CS_AUX_HW_ID_TRACE_ID_MASK, trace_id);
524		hw_id |= FIELD_PREP(CS_AUX_HW_ID_SINK_ID_MASK, coresight_get_sink_id(sink));
525
526		perf_report_aux_output_id(event, hw_id);
527	}
528
529out:
530	/* Tell the perf core the event is alive */
531	event->hw.state = 0;
532	/* Save the event_data for this ETM */
533	ctxt->event_data = event_data;
534	return;
535
536fail_disable_path:
537	coresight_disable_path(path);
538fail_end_stop:
539	/*
540	 * Check if the handle is still associated with the event,
541	 * to handle cases where if the sink failed to start the
542	 * trace and TRUNCATED the handle already.
543	 */
544	if (READ_ONCE(handle->event)) {
545		perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);
546		perf_aux_output_end(handle, 0);
547	}
548fail:
549	event->hw.state = PERF_HES_STOPPED;
550	return;
551}
552
553static void etm_event_stop(struct perf_event *event, int mode)
554{
555	int cpu = smp_processor_id();
556	unsigned long size;
557	struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
558	struct etm_ctxt *ctxt = this_cpu_ptr(&etm_ctxt);
559	struct perf_output_handle *handle = &ctxt->handle;
560	struct etm_event_data *event_data;
561	struct list_head *path;
562
563	/*
564	 * If we still have access to the event_data via handle,
565	 * confirm that we haven't messed up the tracking.
566	 */
567	if (handle->event &&
568	    WARN_ON(perf_get_aux(handle) != ctxt->event_data))
569		return;
570
571	event_data = ctxt->event_data;
572	/* Clear the event_data as this ETM is stopping the trace. */
573	ctxt->event_data = NULL;
574
575	if (event->hw.state == PERF_HES_STOPPED)
576		return;
577
578	/* We must have a valid event_data for a running event */
579	if (WARN_ON(!event_data))
580		return;
581
582	/*
583	 * Check if this ETM was allowed to trace, as decided at
584	 * etm_setup_aux(). If it wasn't allowed to trace, then
585	 * nothing needs to be torn down other than outputting a
586	 * zero sized record.
587	 */
588	if (handle->event && (mode & PERF_EF_UPDATE) &&
589	    !cpumask_test_cpu(cpu, &event_data->mask)) {
590		event->hw.state = PERF_HES_STOPPED;
591		perf_aux_output_end(handle, 0);
592		return;
593	}
594
595	if (!csdev)
596		return;
597
598	path = etm_event_cpu_path(event_data, cpu);
599	if (!path)
600		return;
601
602	sink = coresight_get_sink(path);
603	if (!sink)
604		return;
605
606	/* stop tracer */
607	coresight_disable_source(csdev, event);
608
609	/* tell the core */
610	event->hw.state = PERF_HES_STOPPED;
611
612	/*
613	 * If the handle is not bound to an event anymore
614	 * (e.g, the sink driver was unable to restart the
615	 * handle due to lack of buffer space), we don't
616	 * have to do anything here.
617	 */
618	if (handle->event && (mode & PERF_EF_UPDATE)) {
619		if (WARN_ON_ONCE(handle->event != event))
620			return;
621
622		/* update trace information */
623		if (!sink_ops(sink)->update_buffer)
624			return;
625
626		size = sink_ops(sink)->update_buffer(sink, handle,
627					      event_data->snk_config);
628		/*
629		 * Make sure the handle is still valid as the
630		 * sink could have closed it from an IRQ.
631		 * The sink driver must handle the race with
632		 * update_buffer() and IRQ. Thus either we
633		 * should get a valid handle and valid size
634		 * (which may be 0).
635		 *
636		 * But we should never get a non-zero size with
637		 * an invalid handle.
638		 */
639		if (READ_ONCE(handle->event))
640			perf_aux_output_end(handle, size);
641		else
642			WARN_ON(size);
643	}
644
645	/* Disabling the path make its elements available to other sessions */
646	coresight_disable_path(path);
647}
648
649static int etm_event_add(struct perf_event *event, int mode)
650{
651	int ret = 0;
652	struct hw_perf_event *hwc = &event->hw;
653
654	if (mode & PERF_EF_START) {
655		etm_event_start(event, 0);
656		if (hwc->state & PERF_HES_STOPPED)
657			ret = -EINVAL;
658	} else {
659		hwc->state = PERF_HES_STOPPED;
660	}
661
662	return ret;
663}
664
665static void etm_event_del(struct perf_event *event, int mode)
666{
667	etm_event_stop(event, PERF_EF_UPDATE);
668}
669
670static int etm_addr_filters_validate(struct list_head *filters)
671{
672	bool range = false, address = false;
673	int index = 0;
674	struct perf_addr_filter *filter;
675
676	list_for_each_entry(filter, filters, entry) {
677		/*
678		 * No need to go further if there's no more
679		 * room for filters.
680		 */
681		if (++index > ETM_ADDR_CMP_MAX)
682			return -EOPNOTSUPP;
683
684		/* filter::size==0 means single address trigger */
685		if (filter->size) {
686			/*
687			 * The existing code relies on START/STOP filters
688			 * being address filters.
689			 */
690			if (filter->action == PERF_ADDR_FILTER_ACTION_START ||
691			    filter->action == PERF_ADDR_FILTER_ACTION_STOP)
692				return -EOPNOTSUPP;
693
694			range = true;
695		} else
696			address = true;
697
698		/*
699		 * At this time we don't allow range and start/stop filtering
700		 * to cohabitate, they have to be mutually exclusive.
701		 */
702		if (range && address)
703			return -EOPNOTSUPP;
704	}
705
706	return 0;
707}
708
709static void etm_addr_filters_sync(struct perf_event *event)
710{
711	struct perf_addr_filters_head *head = perf_event_addr_filters(event);
712	unsigned long start, stop;
713	struct perf_addr_filter_range *fr = event->addr_filter_ranges;
714	struct etm_filters *filters = event->hw.addr_filters;
715	struct etm_filter *etm_filter;
716	struct perf_addr_filter *filter;
717	int i = 0;
718
719	list_for_each_entry(filter, &head->list, entry) {
720		start = fr[i].start;
721		stop = start + fr[i].size;
722		etm_filter = &filters->etm_filter[i];
723
724		switch (filter->action) {
725		case PERF_ADDR_FILTER_ACTION_FILTER:
726			etm_filter->start_addr = start;
727			etm_filter->stop_addr = stop;
728			etm_filter->type = ETM_ADDR_TYPE_RANGE;
729			break;
730		case PERF_ADDR_FILTER_ACTION_START:
731			etm_filter->start_addr = start;
732			etm_filter->type = ETM_ADDR_TYPE_START;
733			break;
734		case PERF_ADDR_FILTER_ACTION_STOP:
735			etm_filter->stop_addr = stop;
736			etm_filter->type = ETM_ADDR_TYPE_STOP;
737			break;
738		}
739		i++;
740	}
741
742	filters->nr_filters = i;
743}
744
745int etm_perf_symlink(struct coresight_device *csdev, bool link)
746{
747	char entry[sizeof("cpu9999999")];
748	int ret = 0, cpu = source_ops(csdev)->cpu_id(csdev);
749	struct device *pmu_dev = etm_pmu.dev;
750	struct device *cs_dev = &csdev->dev;
751
752	sprintf(entry, "cpu%d", cpu);
753
754	if (!etm_perf_up)
755		return -EPROBE_DEFER;
756
757	if (link) {
758		ret = sysfs_create_link(&pmu_dev->kobj, &cs_dev->kobj, entry);
759		if (ret)
760			return ret;
761		per_cpu(csdev_src, cpu) = csdev;
762	} else {
763		sysfs_remove_link(&pmu_dev->kobj, entry);
764		per_cpu(csdev_src, cpu) = NULL;
765	}
766
767	return 0;
768}
769EXPORT_SYMBOL_GPL(etm_perf_symlink);
770
771static ssize_t etm_perf_sink_name_show(struct device *dev,
772				       struct device_attribute *dattr,
773				       char *buf)
774{
775	struct dev_ext_attribute *ea;
776
777	ea = container_of(dattr, struct dev_ext_attribute, attr);
778	return scnprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)(ea->var));
779}
780
781static struct dev_ext_attribute *
782etm_perf_add_symlink_group(struct device *dev, const char *name, const char *group_name)
783{
784	struct dev_ext_attribute *ea;
785	unsigned long hash;
786	int ret;
787	struct device *pmu_dev = etm_pmu.dev;
788
789	if (!etm_perf_up)
790		return ERR_PTR(-EPROBE_DEFER);
791
792	ea = devm_kzalloc(dev, sizeof(*ea), GFP_KERNEL);
793	if (!ea)
794		return ERR_PTR(-ENOMEM);
795
796	/*
797	 * If this function is called adding a sink then the hash is used for
798	 * sink selection - see function coresight_get_sink_by_id().
799	 * If adding a configuration then the hash is used for selection in
800	 * cscfg_activate_config()
801	 */
802	hash = hashlen_hash(hashlen_string(NULL, name));
803
804	sysfs_attr_init(&ea->attr.attr);
805	ea->attr.attr.name = devm_kstrdup(dev, name, GFP_KERNEL);
806	if (!ea->attr.attr.name)
807		return ERR_PTR(-ENOMEM);
808
809	ea->attr.attr.mode = 0444;
810	ea->var = (unsigned long *)hash;
811
812	ret = sysfs_add_file_to_group(&pmu_dev->kobj,
813				      &ea->attr.attr, group_name);
814
815	return ret ? ERR_PTR(ret) : ea;
816}
817
818int etm_perf_add_symlink_sink(struct coresight_device *csdev)
819{
820	const char *name;
821	struct device *dev = &csdev->dev;
822	int err = 0;
823
824	if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
825	    csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
826		return -EINVAL;
827
828	if (csdev->ea != NULL)
829		return -EINVAL;
830
831	name = dev_name(dev);
832	csdev->ea = etm_perf_add_symlink_group(dev, name, "sinks");
833	if (IS_ERR(csdev->ea)) {
834		err = PTR_ERR(csdev->ea);
835		csdev->ea = NULL;
836	} else
837		csdev->ea->attr.show = etm_perf_sink_name_show;
838
839	return err;
840}
841
842static void etm_perf_del_symlink_group(struct dev_ext_attribute *ea, const char *group_name)
843{
844	struct device *pmu_dev = etm_pmu.dev;
845
846	sysfs_remove_file_from_group(&pmu_dev->kobj,
847				     &ea->attr.attr, group_name);
848}
849
850void etm_perf_del_symlink_sink(struct coresight_device *csdev)
851{
852	if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
853	    csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
854		return;
855
856	if (!csdev->ea)
857		return;
858
859	etm_perf_del_symlink_group(csdev->ea, "sinks");
860	csdev->ea = NULL;
861}
862
863static ssize_t etm_perf_cscfg_event_show(struct device *dev,
864					 struct device_attribute *dattr,
865					 char *buf)
866{
867	struct dev_ext_attribute *ea;
868
869	ea = container_of(dattr, struct dev_ext_attribute, attr);
870	return scnprintf(buf, PAGE_SIZE, "configid=0x%lx\n", (unsigned long)(ea->var));
871}
872
873int etm_perf_add_symlink_cscfg(struct device *dev, struct cscfg_config_desc *config_desc)
874{
875	int err = 0;
876
877	if (config_desc->event_ea != NULL)
878		return 0;
879
880	config_desc->event_ea = etm_perf_add_symlink_group(dev, config_desc->name, "events");
881
882	/* set the show function to the custom cscfg event */
883	if (!IS_ERR(config_desc->event_ea))
884		config_desc->event_ea->attr.show = etm_perf_cscfg_event_show;
885	else {
886		err = PTR_ERR(config_desc->event_ea);
887		config_desc->event_ea = NULL;
888	}
889
890	return err;
891}
892
893void etm_perf_del_symlink_cscfg(struct cscfg_config_desc *config_desc)
894{
895	if (!config_desc->event_ea)
896		return;
897
898	etm_perf_del_symlink_group(config_desc->event_ea, "events");
899	config_desc->event_ea = NULL;
900}
901
902int __init etm_perf_init(void)
903{
904	int ret;
905
906	etm_pmu.capabilities		= (PERF_PMU_CAP_EXCLUSIVE |
907					   PERF_PMU_CAP_ITRACE);
908
909	etm_pmu.attr_groups		= etm_pmu_attr_groups;
910	etm_pmu.task_ctx_nr		= perf_sw_context;
911	etm_pmu.read			= etm_event_read;
912	etm_pmu.event_init		= etm_event_init;
913	etm_pmu.setup_aux		= etm_setup_aux;
914	etm_pmu.free_aux		= etm_free_aux;
915	etm_pmu.start			= etm_event_start;
916	etm_pmu.stop			= etm_event_stop;
917	etm_pmu.add			= etm_event_add;
918	etm_pmu.del			= etm_event_del;
919	etm_pmu.addr_filters_sync	= etm_addr_filters_sync;
920	etm_pmu.addr_filters_validate	= etm_addr_filters_validate;
921	etm_pmu.nr_addr_filters		= ETM_ADDR_CMP_MAX;
922	etm_pmu.module			= THIS_MODULE;
923
924	ret = perf_pmu_register(&etm_pmu, CORESIGHT_ETM_PMU_NAME, -1);
925	if (ret == 0)
926		etm_perf_up = true;
927
928	return ret;
929}
930
931void etm_perf_exit(void)
932{
933	perf_pmu_unregister(&etm_pmu);
934}