1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2018 Linaro Limited, All rights reserved.
4 * Author: Mike Leach <mike.leach@linaro.org>
5 */
6
7#include <linux/amba/bus.h>
8#include <linux/atomic.h>
9#include <linux/bits.h>
10#include <linux/coresight.h>
11#include <linux/cpu_pm.h>
12#include <linux/cpuhotplug.h>
13#include <linux/device.h>
14#include <linux/io.h>
15#include <linux/kernel.h>
16#include <linux/list.h>
17#include <linux/mutex.h>
18#include <linux/pm_runtime.h>
19#include <linux/property.h>
20#include <linux/spinlock.h>
21
22#include "coresight-priv.h"
23#include "coresight-cti.h"
24
25/*
26 * CTI devices can be associated with a PE, or be connected to CoreSight
27 * hardware. We have a list of all CTIs irrespective of CPU bound or
28 * otherwise.
29 *
30 * We assume that the non-CPU CTIs are always powered as we do with sinks etc.
31 *
32 * We leave the client to figure out if all the CTIs are interconnected with
33 * the same CTM, in general this is the case but does not always have to be.
34 */
35
36/* net of CTI devices connected via CTM */
37static LIST_HEAD(ect_net);
38
39/* protect the list */
40static DEFINE_MUTEX(ect_mutex);
41
42#define csdev_to_cti_drvdata(csdev)	\
43	dev_get_drvdata(csdev->dev.parent)
44
45/* power management handling */
46static int nr_cti_cpu;
47
48/* quick lookup list for CPU bound CTIs when power handling */
49static struct cti_drvdata *cti_cpu_drvdata[NR_CPUS];
50
51/*
52 * CTI naming. CTI bound to cores will have the name cti_cpu<N> where
53 * N is the CPU ID. System CTIs will have the name cti_sys<I> where I
54 * is an index allocated by order of discovery.
55 *
56 * CTI device name list - for CTI not bound to cores.
57 */
58DEFINE_CORESIGHT_DEVLIST(cti_sys_devs, "cti_sys");
59
60/* write set of regs to hardware - call with spinlock claimed */
61void cti_write_all_hw_regs(struct cti_drvdata *drvdata)
62{
63	struct cti_config *config = &drvdata->config;
64	int i;
65
66	CS_UNLOCK(drvdata->base);
67
68	/* disable CTI before writing registers */
69	writel_relaxed(0, drvdata->base + CTICONTROL);
70
71	/* write the CTI trigger registers */
72	for (i = 0; i < config->nr_trig_max; i++) {
73		writel_relaxed(config->ctiinen[i], drvdata->base + CTIINEN(i));
74		writel_relaxed(config->ctiouten[i],
75			       drvdata->base + CTIOUTEN(i));
76	}
77
78	/* other regs */
79	writel_relaxed(config->ctigate, drvdata->base + CTIGATE);
80	writel_relaxed(config->asicctl, drvdata->base + ASICCTL);
81	writel_relaxed(config->ctiappset, drvdata->base + CTIAPPSET);
82
83	/* re-enable CTI */
84	writel_relaxed(1, drvdata->base + CTICONTROL);
85
86	CS_LOCK(drvdata->base);
87}
88
89/* write regs to hardware and enable */
90static int cti_enable_hw(struct cti_drvdata *drvdata)
91{
92	struct cti_config *config = &drvdata->config;
93	unsigned long flags;
94	int rc = 0;
95
96	spin_lock_irqsave(&drvdata->spinlock, flags);
97
98	/* no need to do anything if enabled or unpowered*/
99	if (config->hw_enabled || !config->hw_powered)
100		goto cti_state_unchanged;
101
102	/* claim the device */
103	rc = coresight_claim_device(drvdata->csdev);
104	if (rc)
105		goto cti_err_not_enabled;
106
107	cti_write_all_hw_regs(drvdata);
108
109	config->hw_enabled = true;
110	drvdata->config.enable_req_count++;
111	spin_unlock_irqrestore(&drvdata->spinlock, flags);
112	return rc;
113
114cti_state_unchanged:
115	drvdata->config.enable_req_count++;
116
117	/* cannot enable due to error */
118cti_err_not_enabled:
119	spin_unlock_irqrestore(&drvdata->spinlock, flags);
120	return rc;
121}
122
123/* re-enable CTI on CPU when using CPU hotplug */
124static void cti_cpuhp_enable_hw(struct cti_drvdata *drvdata)
125{
126	struct cti_config *config = &drvdata->config;
127
128	spin_lock(&drvdata->spinlock);
129	config->hw_powered = true;
130
131	/* no need to do anything if no enable request */
132	if (!drvdata->config.enable_req_count)
133		goto cti_hp_not_enabled;
134
135	/* try to claim the device */
136	if (coresight_claim_device(drvdata->csdev))
137		goto cti_hp_not_enabled;
138
139	cti_write_all_hw_regs(drvdata);
140	config->hw_enabled = true;
141	spin_unlock(&drvdata->spinlock);
142	return;
143
144	/* did not re-enable due to no claim / no request */
145cti_hp_not_enabled:
146	spin_unlock(&drvdata->spinlock);
147}
148
149/* disable hardware */
150static int cti_disable_hw(struct cti_drvdata *drvdata)
151{
152	struct cti_config *config = &drvdata->config;
153	struct coresight_device *csdev = drvdata->csdev;
154	int ret = 0;
155
156	spin_lock(&drvdata->spinlock);
157
158	/* don't allow negative refcounts, return an error */
159	if (!drvdata->config.enable_req_count) {
160		ret = -EINVAL;
161		goto cti_not_disabled;
162	}
163
164	/* check refcount - disable on 0 */
165	if (--drvdata->config.enable_req_count > 0)
166		goto cti_not_disabled;
167
168	/* no need to do anything if disabled or cpu unpowered */
169	if (!config->hw_enabled || !config->hw_powered)
170		goto cti_not_disabled;
171
172	CS_UNLOCK(drvdata->base);
173
174	/* disable CTI */
175	writel_relaxed(0, drvdata->base + CTICONTROL);
176	config->hw_enabled = false;
177
178	coresight_disclaim_device_unlocked(csdev);
179	CS_LOCK(drvdata->base);
180	spin_unlock(&drvdata->spinlock);
181	return ret;
182
183	/* not disabled this call */
184cti_not_disabled:
185	spin_unlock(&drvdata->spinlock);
186	return ret;
187}
188
189void cti_write_single_reg(struct cti_drvdata *drvdata, int offset, u32 value)
190{
191	CS_UNLOCK(drvdata->base);
192	writel_relaxed(value, drvdata->base + offset);
193	CS_LOCK(drvdata->base);
194}
195
196void cti_write_intack(struct device *dev, u32 ackval)
197{
198	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
199	struct cti_config *config = &drvdata->config;
200
201	spin_lock(&drvdata->spinlock);
202	/* write if enabled */
203	if (cti_active(config))
204		cti_write_single_reg(drvdata, CTIINTACK, ackval);
205	spin_unlock(&drvdata->spinlock);
206}
207
208/*
209 * Look at the HW DEVID register for some of the HW settings.
210 * DEVID[15:8] - max number of in / out triggers.
211 */
212#define CTI_DEVID_MAXTRIGS(devid_val) ((int) BMVAL(devid_val, 8, 15))
213
214/* DEVID[19:16] - number of CTM channels */
215#define CTI_DEVID_CTMCHANNELS(devid_val) ((int) BMVAL(devid_val, 16, 19))
216
217static void cti_set_default_config(struct device *dev,
218				   struct cti_drvdata *drvdata)
219{
220	struct cti_config *config = &drvdata->config;
221	u32 devid;
222
223	devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
224	config->nr_trig_max = CTI_DEVID_MAXTRIGS(devid);
225
226	/*
227	 * no current hardware should exceed this, but protect the driver
228	 * in case of fault / out of spec hw
229	 */
230	if (config->nr_trig_max > CTIINOUTEN_MAX) {
231		dev_warn_once(dev,
232			"Limiting HW MaxTrig value(%d) to driver max(%d)\n",
233			config->nr_trig_max, CTIINOUTEN_MAX);
234		config->nr_trig_max = CTIINOUTEN_MAX;
235	}
236
237	config->nr_ctm_channels = CTI_DEVID_CTMCHANNELS(devid);
238
239	/* Most regs default to 0 as zalloc'ed except...*/
240	config->trig_filter_enable = true;
241	config->ctigate = GENMASK(config->nr_ctm_channels - 1, 0);
242	config->enable_req_count = 0;
243}
244
245/*
246 * Add a connection entry to the list of connections for this
247 * CTI device.
248 */
249int cti_add_connection_entry(struct device *dev, struct cti_drvdata *drvdata,
250			     struct cti_trig_con *tc,
251			     struct coresight_device *csdev,
252			     const char *assoc_dev_name)
253{
254	struct cti_device *cti_dev = &drvdata->ctidev;
255
256	tc->con_dev = csdev;
257	/*
258	 * Prefer actual associated CS device dev name to supplied value -
259	 * which is likely to be node name / other conn name.
260	 */
261	if (csdev)
262		tc->con_dev_name = dev_name(&csdev->dev);
263	else if (assoc_dev_name != NULL) {
264		tc->con_dev_name = devm_kstrdup(dev,
265						assoc_dev_name, GFP_KERNEL);
266		if (!tc->con_dev_name)
267			return -ENOMEM;
268	}
269	list_add_tail(&tc->node, &cti_dev->trig_cons);
270	cti_dev->nr_trig_con++;
271
272	/* add connection usage bit info to overall info */
273	drvdata->config.trig_in_use |= tc->con_in->used_mask;
274	drvdata->config.trig_out_use |= tc->con_out->used_mask;
275
276	return 0;
277}
278
279/* create a trigger connection with appropriately sized signal groups */
280struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int in_sigs,
281					   int out_sigs)
282{
283	struct cti_trig_con *tc = NULL;
284	struct cti_trig_grp *in = NULL, *out = NULL;
285
286	tc = devm_kzalloc(dev, sizeof(struct cti_trig_con), GFP_KERNEL);
287	if (!tc)
288		return tc;
289
290	in = devm_kzalloc(dev,
291			  offsetof(struct cti_trig_grp, sig_types[in_sigs]),
292			  GFP_KERNEL);
293	if (!in)
294		return NULL;
295
296	out = devm_kzalloc(dev,
297			   offsetof(struct cti_trig_grp, sig_types[out_sigs]),
298			   GFP_KERNEL);
299	if (!out)
300		return NULL;
301
302	tc->con_in = in;
303	tc->con_out = out;
304	tc->con_in->nr_sigs = in_sigs;
305	tc->con_out->nr_sigs = out_sigs;
306	return tc;
307}
308
309/*
310 * Add a default connection if nothing else is specified.
311 * single connection based on max in/out info, no assoc device
312 */
313int cti_add_default_connection(struct device *dev, struct cti_drvdata *drvdata)
314{
315	int ret = 0;
316	int n_trigs = drvdata->config.nr_trig_max;
317	u32 n_trig_mask = GENMASK(n_trigs - 1, 0);
318	struct cti_trig_con *tc = NULL;
319
320	/*
321	 * Assume max trigs for in and out,
322	 * all used, default sig types allocated
323	 */
324	tc = cti_allocate_trig_con(dev, n_trigs, n_trigs);
325	if (!tc)
326		return -ENOMEM;
327
328	tc->con_in->used_mask = n_trig_mask;
329	tc->con_out->used_mask = n_trig_mask;
330	ret = cti_add_connection_entry(dev, drvdata, tc, NULL, "default");
331	return ret;
332}
333
334/** cti channel api **/
335/* attach/detach channel from trigger - write through if enabled. */
336int cti_channel_trig_op(struct device *dev, enum cti_chan_op op,
337			enum cti_trig_dir direction, u32 channel_idx,
338			u32 trigger_idx)
339{
340	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
341	struct cti_config *config = &drvdata->config;
342	u32 trig_bitmask;
343	u32 chan_bitmask;
344	u32 reg_value;
345	int reg_offset;
346
347	/* ensure indexes in range */
348	if ((channel_idx >= config->nr_ctm_channels) ||
349	   (trigger_idx >= config->nr_trig_max))
350		return -EINVAL;
351
352	trig_bitmask = BIT(trigger_idx);
353
354	/* ensure registered triggers and not out filtered */
355	if (direction == CTI_TRIG_IN)	{
356		if (!(trig_bitmask & config->trig_in_use))
357			return -EINVAL;
358	} else {
359		if (!(trig_bitmask & config->trig_out_use))
360			return -EINVAL;
361
362		if ((config->trig_filter_enable) &&
363		    (config->trig_out_filter & trig_bitmask))
364			return -EINVAL;
365	}
366
367	/* update the local register values */
368	chan_bitmask = BIT(channel_idx);
369	reg_offset = (direction == CTI_TRIG_IN ? CTIINEN(trigger_idx) :
370		      CTIOUTEN(trigger_idx));
371
372	spin_lock(&drvdata->spinlock);
373
374	/* read - modify write - the trigger / channel enable value */
375	reg_value = direction == CTI_TRIG_IN ? config->ctiinen[trigger_idx] :
376		     config->ctiouten[trigger_idx];
377	if (op == CTI_CHAN_ATTACH)
378		reg_value |= chan_bitmask;
379	else
380		reg_value &= ~chan_bitmask;
381
382	/* write local copy */
383	if (direction == CTI_TRIG_IN)
384		config->ctiinen[trigger_idx] = reg_value;
385	else
386		config->ctiouten[trigger_idx] = reg_value;
387
388	/* write through if enabled */
389	if (cti_active(config))
390		cti_write_single_reg(drvdata, reg_offset, reg_value);
391	spin_unlock(&drvdata->spinlock);
392	return 0;
393}
394
395int cti_channel_gate_op(struct device *dev, enum cti_chan_gate_op op,
396			u32 channel_idx)
397{
398	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
399	struct cti_config *config = &drvdata->config;
400	u32 chan_bitmask;
401	u32 reg_value;
402	int err = 0;
403
404	if (channel_idx >= config->nr_ctm_channels)
405		return -EINVAL;
406
407	chan_bitmask = BIT(channel_idx);
408
409	spin_lock(&drvdata->spinlock);
410	reg_value = config->ctigate;
411	switch (op) {
412	case CTI_GATE_CHAN_ENABLE:
413		reg_value |= chan_bitmask;
414		break;
415
416	case CTI_GATE_CHAN_DISABLE:
417		reg_value &= ~chan_bitmask;
418		break;
419
420	default:
421		err = -EINVAL;
422		break;
423	}
424	if (err == 0) {
425		config->ctigate = reg_value;
426		if (cti_active(config))
427			cti_write_single_reg(drvdata, CTIGATE, reg_value);
428	}
429	spin_unlock(&drvdata->spinlock);
430	return err;
431}
432
433int cti_channel_setop(struct device *dev, enum cti_chan_set_op op,
434		      u32 channel_idx)
435{
436	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
437	struct cti_config *config = &drvdata->config;
438	u32 chan_bitmask;
439	u32 reg_value;
440	u32 reg_offset;
441	int err = 0;
442
443	if (channel_idx >= config->nr_ctm_channels)
444		return -EINVAL;
445
446	chan_bitmask = BIT(channel_idx);
447
448	spin_lock(&drvdata->spinlock);
449	reg_value = config->ctiappset;
450	switch (op) {
451	case CTI_CHAN_SET:
452		config->ctiappset |= chan_bitmask;
453		reg_value  = config->ctiappset;
454		reg_offset = CTIAPPSET;
455		break;
456
457	case CTI_CHAN_CLR:
458		config->ctiappset &= ~chan_bitmask;
459		reg_value = chan_bitmask;
460		reg_offset = CTIAPPCLEAR;
461		break;
462
463	case CTI_CHAN_PULSE:
464		config->ctiappset &= ~chan_bitmask;
465		reg_value = chan_bitmask;
466		reg_offset = CTIAPPPULSE;
467		break;
468
469	default:
470		err = -EINVAL;
471		break;
472	}
473
474	if ((err == 0) && cti_active(config))
475		cti_write_single_reg(drvdata, reg_offset, reg_value);
476	spin_unlock(&drvdata->spinlock);
477
478	return err;
479}
480
481static bool cti_add_sysfs_link(struct cti_drvdata *drvdata,
482			       struct cti_trig_con *tc)
483{
484	struct coresight_sysfs_link link_info;
485	int link_err = 0;
486
487	link_info.orig = drvdata->csdev;
488	link_info.orig_name = tc->con_dev_name;
489	link_info.target = tc->con_dev;
490	link_info.target_name = dev_name(&drvdata->csdev->dev);
491
492	link_err = coresight_add_sysfs_link(&link_info);
493	if (link_err)
494		dev_warn(&drvdata->csdev->dev,
495			 "Failed to set CTI sysfs link %s<=>%s\n",
496			 link_info.orig_name, link_info.target_name);
497	return !link_err;
498}
499
500static void cti_remove_sysfs_link(struct cti_drvdata *drvdata,
501				  struct cti_trig_con *tc)
502{
503	struct coresight_sysfs_link link_info;
504
505	link_info.orig = drvdata->csdev;
506	link_info.orig_name = tc->con_dev_name;
507	link_info.target = tc->con_dev;
508	link_info.target_name = dev_name(&drvdata->csdev->dev);
509	coresight_remove_sysfs_link(&link_info);
510}
511
512/*
513 * Look for a matching connection device name in the list of connections.
514 * If found then swap in the csdev name, set trig con association pointer
515 * and return found.
516 */
517static bool
518cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name,
519		      struct coresight_device *csdev)
520{
521	struct cti_trig_con *tc;
522	struct cti_drvdata *drvdata = container_of(ctidev, struct cti_drvdata,
523						   ctidev);
524
525	list_for_each_entry(tc, &ctidev->trig_cons, node) {
526		if (tc->con_dev_name) {
527			if (!strcmp(node_name, tc->con_dev_name)) {
528				/* match: so swap in csdev name & dev */
529				tc->con_dev_name = dev_name(&csdev->dev);
530				tc->con_dev = csdev;
531				/* try to set sysfs link */
532				if (cti_add_sysfs_link(drvdata, tc))
533					return true;
534				/* link failed - remove CTI reference */
535				tc->con_dev = NULL;
536				break;
537			}
538		}
539	}
540	return false;
541}
542
543/*
544 * Search the cti list to add an associated CTI into the supplied CS device
545 * This will set the association if CTI declared before the CS device.
546 * (called from coresight_register() without coresight_mutex locked).
547 */
548static void cti_add_assoc_to_csdev(struct coresight_device *csdev)
549{
550	struct cti_drvdata *ect_item;
551	struct cti_device *ctidev;
552	const char *node_name = NULL;
553
554	/* protect the list */
555	mutex_lock(&ect_mutex);
556
557	/* exit if current is an ECT device.*/
558	if ((csdev->type == CORESIGHT_DEV_TYPE_HELPER &&
559	     csdev->subtype.helper_subtype ==
560		     CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI) ||
561	    list_empty(&ect_net))
562		goto cti_add_done;
563
564	/* if we didn't find the csdev previously we used the fwnode name */
565	node_name = cti_plat_get_node_name(dev_fwnode(csdev->dev.parent));
566	if (!node_name)
567		goto cti_add_done;
568
569	/* for each CTI in list... */
570	list_for_each_entry(ect_item, &ect_net, node) {
571		ctidev = &ect_item->ctidev;
572		if (cti_match_fixup_csdev(ctidev, node_name, csdev)) {
573			/*
574			 * if we found a matching csdev then update the ECT
575			 * association pointer for the device with this CTI.
576			 */
577			coresight_add_helper(csdev, ect_item->csdev);
578			break;
579		}
580	}
581cti_add_done:
582	mutex_unlock(&ect_mutex);
583}
584
585/*
586 * Removing the associated devices is easier.
587 */
588static void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
589{
590	struct cti_drvdata *ctidrv;
591	struct cti_trig_con *tc;
592	struct cti_device *ctidev;
593	union coresight_dev_subtype cti_subtype = {
594		.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI
595	};
596	struct coresight_device *cti_csdev = coresight_find_output_type(
597		csdev->pdata, CORESIGHT_DEV_TYPE_HELPER, cti_subtype);
598
599	if (!cti_csdev)
600		return;
601
602	mutex_lock(&ect_mutex);
603	ctidrv = csdev_to_cti_drvdata(cti_csdev);
604	ctidev = &ctidrv->ctidev;
605	list_for_each_entry(tc, &ctidev->trig_cons, node) {
606		if (tc->con_dev == csdev) {
607			cti_remove_sysfs_link(ctidrv, tc);
608			tc->con_dev = NULL;
609			break;
610		}
611	}
612	mutex_unlock(&ect_mutex);
613}
614
615/*
616 * Operations to add and remove associated CTI.
617 * Register to coresight core driver as call back function.
618 */
619static struct cti_assoc_op cti_assoc_ops = {
620	.add = cti_add_assoc_to_csdev,
621	.remove = cti_remove_assoc_from_csdev
622};
623
624/*
625 * Update the cross references where the associated device was found
626 * while we were building the connection info. This will occur if the
627 * assoc device was registered before the CTI.
628 */
629static void cti_update_conn_xrefs(struct cti_drvdata *drvdata)
630{
631	struct cti_trig_con *tc;
632	struct cti_device *ctidev = &drvdata->ctidev;
633
634	list_for_each_entry(tc, &ctidev->trig_cons, node) {
635		if (tc->con_dev) {
636			/* if we can set the sysfs link */
637			if (cti_add_sysfs_link(drvdata, tc))
638				/* set the CTI/csdev association */
639				coresight_add_helper(tc->con_dev,
640						     drvdata->csdev);
641			else
642				/* otherwise remove reference from CTI */
643				tc->con_dev = NULL;
644		}
645	}
646}
647
648static void cti_remove_conn_xrefs(struct cti_drvdata *drvdata)
649{
650	struct cti_trig_con *tc;
651	struct cti_device *ctidev = &drvdata->ctidev;
652
653	list_for_each_entry(tc, &ctidev->trig_cons, node) {
654		if (tc->con_dev) {
655			cti_remove_sysfs_link(drvdata, tc);
656			tc->con_dev = NULL;
657		}
658	}
659}
660
661/** cti PM callbacks **/
662static int cti_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd,
663			     void *v)
664{
665	struct cti_drvdata *drvdata;
666	struct coresight_device *csdev;
667	unsigned int cpu = smp_processor_id();
668	int notify_res = NOTIFY_OK;
669
670	if (!cti_cpu_drvdata[cpu])
671		return NOTIFY_OK;
672
673	drvdata = cti_cpu_drvdata[cpu];
674	csdev = drvdata->csdev;
675
676	if (WARN_ON_ONCE(drvdata->ctidev.cpu != cpu))
677		return NOTIFY_BAD;
678
679	spin_lock(&drvdata->spinlock);
680
681	switch (cmd) {
682	case CPU_PM_ENTER:
683		/* CTI regs all static - we have a copy & nothing to save */
684		drvdata->config.hw_powered = false;
685		if (drvdata->config.hw_enabled)
686			coresight_disclaim_device(csdev);
687		break;
688
689	case CPU_PM_ENTER_FAILED:
690		drvdata->config.hw_powered = true;
691		if (drvdata->config.hw_enabled) {
692			if (coresight_claim_device(csdev))
693				drvdata->config.hw_enabled = false;
694		}
695		break;
696
697	case CPU_PM_EXIT:
698		/* write hardware registers to re-enable. */
699		drvdata->config.hw_powered = true;
700		drvdata->config.hw_enabled = false;
701
702		/* check enable reference count to enable HW */
703		if (drvdata->config.enable_req_count) {
704			/* check we can claim the device as we re-power */
705			if (coresight_claim_device(csdev))
706				goto cti_notify_exit;
707
708			drvdata->config.hw_enabled = true;
709			cti_write_all_hw_regs(drvdata);
710		}
711		break;
712
713	default:
714		notify_res = NOTIFY_DONE;
715		break;
716	}
717
718cti_notify_exit:
719	spin_unlock(&drvdata->spinlock);
720	return notify_res;
721}
722
723static struct notifier_block cti_cpu_pm_nb = {
724	.notifier_call = cti_cpu_pm_notify,
725};
726
727/* CPU HP handlers */
728static int cti_starting_cpu(unsigned int cpu)
729{
730	struct cti_drvdata *drvdata = cti_cpu_drvdata[cpu];
731
732	if (!drvdata)
733		return 0;
734
735	cti_cpuhp_enable_hw(drvdata);
736	return 0;
737}
738
739static int cti_dying_cpu(unsigned int cpu)
740{
741	struct cti_drvdata *drvdata = cti_cpu_drvdata[cpu];
742
743	if (!drvdata)
744		return 0;
745
746	spin_lock(&drvdata->spinlock);
747	drvdata->config.hw_powered = false;
748	if (drvdata->config.hw_enabled)
749		coresight_disclaim_device(drvdata->csdev);
750	spin_unlock(&drvdata->spinlock);
751	return 0;
752}
753
754static int cti_pm_setup(struct cti_drvdata *drvdata)
755{
756	int ret;
757
758	if (drvdata->ctidev.cpu == -1)
759		return 0;
760
761	if (nr_cti_cpu)
762		goto done;
763
764	cpus_read_lock();
765	ret = cpuhp_setup_state_nocalls_cpuslocked(
766			CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
767			"arm/coresight_cti:starting",
768			cti_starting_cpu, cti_dying_cpu);
769	if (ret) {
770		cpus_read_unlock();
771		return ret;
772	}
773
774	ret = cpu_pm_register_notifier(&cti_cpu_pm_nb);
775	cpus_read_unlock();
776	if (ret) {
777		cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_CTI_STARTING);
778		return ret;
779	}
780
781done:
782	nr_cti_cpu++;
783	cti_cpu_drvdata[drvdata->ctidev.cpu] = drvdata;
784
785	return 0;
786}
787
788/* release PM registrations */
789static void cti_pm_release(struct cti_drvdata *drvdata)
790{
791	if (drvdata->ctidev.cpu == -1)
792		return;
793
794	cti_cpu_drvdata[drvdata->ctidev.cpu] = NULL;
795	if (--nr_cti_cpu == 0) {
796		cpu_pm_unregister_notifier(&cti_cpu_pm_nb);
797		cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_CTI_STARTING);
798	}
799}
800
801/** cti ect operations **/
802int cti_enable(struct coresight_device *csdev, enum cs_mode mode, void *data)
803{
804	struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
805
806	return cti_enable_hw(drvdata);
807}
808
809int cti_disable(struct coresight_device *csdev, void *data)
810{
811	struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
812
813	return cti_disable_hw(drvdata);
814}
815
816static const struct coresight_ops_helper cti_ops_ect = {
817	.enable = cti_enable,
818	.disable = cti_disable,
819};
820
821static const struct coresight_ops cti_ops = {
822	.helper_ops = &cti_ops_ect,
823};
824
825/*
826 * Free up CTI specific resources
827 * called by dev->release, need to call down to underlying csdev release.
828 */
829static void cti_device_release(struct device *dev)
830{
831	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
832	struct cti_drvdata *ect_item, *ect_tmp;
833
834	mutex_lock(&ect_mutex);
835	cti_pm_release(drvdata);
836
837	/* remove from the list */
838	list_for_each_entry_safe(ect_item, ect_tmp, &ect_net, node) {
839		if (ect_item == drvdata) {
840			list_del(&ect_item->node);
841			break;
842		}
843	}
844	mutex_unlock(&ect_mutex);
845
846	if (drvdata->csdev_release)
847		drvdata->csdev_release(dev);
848}
849static void cti_remove(struct amba_device *adev)
850{
851	struct cti_drvdata *drvdata = dev_get_drvdata(&adev->dev);
852
853	mutex_lock(&ect_mutex);
854	cti_remove_conn_xrefs(drvdata);
855	mutex_unlock(&ect_mutex);
856
857	coresight_unregister(drvdata->csdev);
858}
859
860static int cti_probe(struct amba_device *adev, const struct amba_id *id)
861{
862	int ret = 0;
863	void __iomem *base;
864	struct device *dev = &adev->dev;
865	struct cti_drvdata *drvdata = NULL;
866	struct coresight_desc cti_desc;
867	struct coresight_platform_data *pdata = NULL;
868	struct resource *res = &adev->res;
869
870	/* driver data*/
871	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
872	if (!drvdata)
873		return -ENOMEM;
874
875	/* Validity for the resource is already checked by the AMBA core */
876	base = devm_ioremap_resource(dev, res);
877	if (IS_ERR(base))
878		return PTR_ERR(base);
879
880	drvdata->base = base;
881	cti_desc.access = CSDEV_ACCESS_IOMEM(base);
882
883	dev_set_drvdata(dev, drvdata);
884
885	/* default CTI device info  */
886	drvdata->ctidev.cpu = -1;
887	drvdata->ctidev.nr_trig_con = 0;
888	drvdata->ctidev.ctm_id = 0;
889	INIT_LIST_HEAD(&drvdata->ctidev.trig_cons);
890
891	spin_lock_init(&drvdata->spinlock);
892
893	/* initialise CTI driver config values */
894	cti_set_default_config(dev, drvdata);
895
896	pdata = coresight_cti_get_platform_data(dev);
897	if (IS_ERR(pdata)) {
898		dev_err(dev, "coresight_cti_get_platform_data err\n");
899		return  PTR_ERR(pdata);
900	}
901
902	/* default to powered - could change on PM notifications */
903	drvdata->config.hw_powered = true;
904
905	/* set up device name - will depend if cpu bound or otherwise */
906	if (drvdata->ctidev.cpu >= 0)
907		cti_desc.name = devm_kasprintf(dev, GFP_KERNEL, "cti_cpu%d",
908					       drvdata->ctidev.cpu);
909	else
910		cti_desc.name = coresight_alloc_device_name(&cti_sys_devs, dev);
911	if (!cti_desc.name)
912		return -ENOMEM;
913
914	/* setup CPU power management handling for CPU bound CTI devices. */
915	ret = cti_pm_setup(drvdata);
916	if (ret)
917		return ret;
918
919	/* create dynamic attributes for connections */
920	ret = cti_create_cons_sysfs(dev, drvdata);
921	if (ret) {
922		dev_err(dev, "%s: create dynamic sysfs entries failed\n",
923			cti_desc.name);
924		goto pm_release;
925	}
926
927	/* set up coresight component description */
928	cti_desc.pdata = pdata;
929	cti_desc.type = CORESIGHT_DEV_TYPE_HELPER;
930	cti_desc.subtype.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI;
931	cti_desc.ops = &cti_ops;
932	cti_desc.groups = drvdata->ctidev.con_groups;
933	cti_desc.dev = dev;
934	drvdata->csdev = coresight_register(&cti_desc);
935	if (IS_ERR(drvdata->csdev)) {
936		ret = PTR_ERR(drvdata->csdev);
937		goto pm_release;
938	}
939
940	/* add to list of CTI devices */
941	mutex_lock(&ect_mutex);
942	list_add(&drvdata->node, &ect_net);
943	/* set any cross references */
944	cti_update_conn_xrefs(drvdata);
945	mutex_unlock(&ect_mutex);
946
947	/* set up release chain */
948	drvdata->csdev_release = drvdata->csdev->dev.release;
949	drvdata->csdev->dev.release = cti_device_release;
950
951	/* all done - dec pm refcount */
952	pm_runtime_put(&adev->dev);
953	dev_info(&drvdata->csdev->dev, "CTI initialized\n");
954	return 0;
955
956pm_release:
957	cti_pm_release(drvdata);
958	return ret;
959}
960
961static struct amba_cs_uci_id uci_id_cti[] = {
962	{
963		/*  CTI UCI data */
964		.devarch	= 0x47701a14, /* CTI v2 */
965		.devarch_mask	= 0xfff0ffff,
966		.devtype	= 0x00000014, /* maj(0x4-debug) min(0x1-ECT) */
967	}
968};
969
970static const struct amba_id cti_ids[] = {
971	CS_AMBA_ID(0x000bb906), /* Coresight CTI (SoC 400), C-A72, C-A57 */
972	CS_AMBA_ID(0x000bb922), /* CTI - C-A8 */
973	CS_AMBA_ID(0x000bb9a8), /* CTI - C-A53 */
974	CS_AMBA_ID(0x000bb9aa), /* CTI - C-A73 */
975	CS_AMBA_UCI_ID(0x000bb9da, uci_id_cti), /* CTI - C-A35 */
976	CS_AMBA_UCI_ID(0x000bb9ed, uci_id_cti), /* Coresight CTI (SoC 600) */
977	{ 0, 0, NULL },
978};
979
980MODULE_DEVICE_TABLE(amba, cti_ids);
981
982static struct amba_driver cti_driver = {
983	.drv = {
984		.name	= "coresight-cti",
985		.owner = THIS_MODULE,
986		.suppress_bind_attrs = true,
987	},
988	.probe		= cti_probe,
989	.remove		= cti_remove,
990	.id_table	= cti_ids,
991};
992
993static int __init cti_init(void)
994{
995	int ret;
996
997	ret = amba_driver_register(&cti_driver);
998	if (ret)
999		pr_info("Error registering cti driver\n");
1000	coresight_set_cti_ops(&cti_assoc_ops);
1001	return ret;
1002}
1003
1004static void __exit cti_exit(void)
1005{
1006	coresight_remove_cti_ops();
1007	amba_driver_unregister(&cti_driver);
1008}
1009
1010module_init(cti_init);
1011module_exit(cti_exit);
1012
1013MODULE_AUTHOR("Mike Leach <mike.leach@linaro.org>");
1014MODULE_DESCRIPTION("Arm CoreSight CTI Driver");
1015MODULE_LICENSE("GPL v2");
1016