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(addr: 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(addr: 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(csdev: 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(lock: &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(lock: &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(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(csdev: drvdata->csdev))
137 goto cti_hp_not_enabled;
138
139 cti_write_all_hw_regs(drvdata);
140 config->hw_enabled = true;
141 spin_unlock(lock: &drvdata->spinlock);
142 return;
143
144 /* did not re-enable due to no claim / no request */
145cti_hp_not_enabled:
146 spin_unlock(lock: &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(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(addr: 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(addr: drvdata->base);
180 spin_unlock(lock: &drvdata->spinlock);
181 return ret;
182
183 /* not disabled this call */
184cti_not_disabled:
185 spin_unlock(lock: &drvdata->spinlock);
186 return ret;
187}
188
189void cti_write_single_reg(struct cti_drvdata *drvdata, int offset, u32 value)
190{
191 CS_UNLOCK(addr: drvdata->base);
192 writel_relaxed(value, drvdata->base + offset);
193 CS_LOCK(addr: drvdata->base);
194}
195
196void cti_write_intack(struct device *dev, u32 ackval)
197{
198 struct cti_drvdata *drvdata = dev_get_drvdata(dev: dev->parent);
199 struct cti_config *config = &drvdata->config;
200
201 spin_lock(lock: &drvdata->spinlock);
202 /* write if enabled */
203 if (cti_active(cfg: config))
204 cti_write_single_reg(drvdata, CTIINTACK, value: ackval);
205 spin_unlock(lock: &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(dev: &csdev->dev);
263 else if (assoc_dev_name != NULL) {
264 tc->con_dev_name = devm_kstrdup(dev,
265 s: assoc_dev_name, GFP_KERNEL);
266 if (!tc->con_dev_name)
267 return -ENOMEM;
268 }
269 list_add_tail(new: &tc->node, head: &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, size: 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, in_sigs: n_trigs, out_sigs: 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, assoc_dev_name: "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: 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(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(cfg: config))
390 cti_write_single_reg(drvdata, offset: reg_offset, value: reg_value);
391 spin_unlock(lock: &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: 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(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(cfg: config))
427 cti_write_single_reg(drvdata, CTIGATE, value: reg_value);
428 }
429 spin_unlock(lock: &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: 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(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(cfg: config))
475 cti_write_single_reg(drvdata, offset: reg_offset, value: reg_value);
476 spin_unlock(lock: &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(dev: &drvdata->csdev->dev);
491
492 link_err = coresight_add_sysfs_link(info: &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(dev: &drvdata->csdev->dev);
509 coresight_remove_sysfs_link(info: &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(dev: &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(head: &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, helper: ect_item->csdev);
578 break;
579 }
580 }
581cti_add_done:
582 mutex_unlock(lock: &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 pdata: csdev->pdata, type: CORESIGHT_DEV_TYPE_HELPER, subtype: 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(drvdata: ctidrv, tc);
608 tc->con_dev = NULL;
609 break;
610 }
611 }
612 mutex_unlock(lock: &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(csdev: tc->con_dev,
640 helper: 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(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(lock: &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(lock: &drvdata->spinlock);
747 drvdata->config.hw_powered = false;
748 if (drvdata->config.hw_enabled)
749 coresight_disclaim_device(csdev: drvdata->csdev);
750 spin_unlock(lock: &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 state: CPUHP_AP_ARM_CORESIGHT_CTI_STARTING,
767 name: "arm/coresight_cti:starting",
768 startup: cti_starting_cpu, teardown: cti_dying_cpu);
769 if (ret) {
770 cpus_read_unlock();
771 return ret;
772 }
773
774 ret = cpu_pm_register_notifier(nb: &cti_cpu_pm_nb);
775 cpus_read_unlock();
776 if (ret) {
777 cpuhp_remove_state_nocalls(state: 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(nb: &cti_cpu_pm_nb);
797 cpuhp_remove_state_nocalls(state: 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: 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(entry: &ect_item->node);
841 break;
842 }
843 }
844 mutex_unlock(lock: &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(dev: &adev->dev);
852
853 mutex_lock(&ect_mutex);
854 cti_remove_conn_xrefs(drvdata);
855 mutex_unlock(lock: &ect_mutex);
856
857 coresight_unregister(csdev: 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, size: 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(ptr: base))
878 return PTR_ERR(ptr: base);
879
880 drvdata->base = base;
881 cti_desc.access = CSDEV_ACCESS_IOMEM(base);
882
883 dev_set_drvdata(dev, data: 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(list: &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(ptr: pdata)) {
898 dev_err(dev, "coresight_cti_get_platform_data err\n");
899 return PTR_ERR(ptr: 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, fmt: "cti_cpu%d",
908 drvdata->ctidev.cpu);
909 else
910 cti_desc.name = coresight_alloc_device_name(devs: &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(desc: &cti_desc);
935 if (IS_ERR(ptr: drvdata->csdev)) {
936 ret = PTR_ERR(ptr: drvdata->csdev);
937 goto pm_release;
938 }
939
940 /* add to list of CTI devices */
941 mutex_lock(&ect_mutex);
942 list_add(new: &drvdata->node, head: &ect_net);
943 /* set any cross references */
944 cti_update_conn_xrefs(drvdata);
945 mutex_unlock(lock: &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(dev: &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(drv: &cti_driver);
998 if (ret)
999 pr_info("Error registering cti driver\n");
1000 coresight_set_cti_ops(cti_op: &cti_assoc_ops);
1001 return ret;
1002}
1003
1004static void __exit cti_exit(void)
1005{
1006 coresight_remove_cti_ops();
1007 amba_driver_unregister(drv: &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

source code of linux/drivers/hwtracing/coresight/coresight-cti-core.c