xref: /openbmc/linux/drivers/bus/arm-cci.c (revision 0da85d1e)
1 /*
2  * CCI cache coherent interconnect driver
3  *
4  * Copyright (C) 2013 ARM Ltd.
5  * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
12  * kind, whether express or implied; without even the implied warranty
13  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/arm-cci.h>
18 #include <linux/io.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <linux/of_address.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_platform.h>
24 #include <linux/perf_event.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 
29 #include <asm/cacheflush.h>
30 #include <asm/smp_plat.h>
31 
32 static void __iomem *cci_ctrl_base;
33 static unsigned long cci_ctrl_phys;
34 
35 #ifdef CONFIG_ARM_CCI400_PORT_CTRL
36 struct cci_nb_ports {
37 	unsigned int nb_ace;
38 	unsigned int nb_ace_lite;
39 };
40 
41 static const struct cci_nb_ports cci400_ports = {
42 	.nb_ace = 2,
43 	.nb_ace_lite = 3
44 };
45 
46 #define CCI400_PORTS_DATA	(&cci400_ports)
47 #else
48 #define CCI400_PORTS_DATA	(NULL)
49 #endif
50 
51 static const struct of_device_id arm_cci_matches[] = {
52 #ifdef CONFIG_ARM_CCI400_COMMON
53 	{.compatible = "arm,cci-400", .data = CCI400_PORTS_DATA },
54 #endif
55 	{},
56 };
57 
58 #ifdef CONFIG_ARM_CCI400_PMU
59 
60 #define DRIVER_NAME		"CCI-400"
61 #define DRIVER_NAME_PMU		DRIVER_NAME " PMU"
62 
63 #define CCI_PMCR		0x0100
64 #define CCI_PID2		0x0fe8
65 
66 #define CCI_PMCR_CEN		0x00000001
67 #define CCI_PMCR_NCNT_MASK	0x0000f800
68 #define CCI_PMCR_NCNT_SHIFT	11
69 
70 #define CCI_PID2_REV_MASK	0xf0
71 #define CCI_PID2_REV_SHIFT	4
72 
73 #define CCI_PMU_EVT_SEL		0x000
74 #define CCI_PMU_CNTR		0x004
75 #define CCI_PMU_CNTR_CTRL	0x008
76 #define CCI_PMU_OVRFLW		0x00c
77 
78 #define CCI_PMU_OVRFLW_FLAG	1
79 
80 #define CCI_PMU_CNTR_BASE(idx)	((idx) * SZ_4K)
81 
82 #define CCI_PMU_CNTR_MASK	((1ULL << 32) -1)
83 
84 #define CCI_PMU_EVENT_MASK		0xffUL
85 #define CCI_PMU_EVENT_SOURCE(event)	((event >> 5) & 0x7)
86 #define CCI_PMU_EVENT_CODE(event)	(event & 0x1f)
87 
88 #define CCI_PMU_MAX_HW_EVENTS 5   /* CCI PMU has 4 counters + 1 cycle counter */
89 
90 /* Types of interfaces that can generate events */
91 enum {
92 	CCI_IF_SLAVE,
93 	CCI_IF_MASTER,
94 	CCI_IF_MAX,
95 };
96 
97 struct event_range {
98 	u32 min;
99 	u32 max;
100 };
101 
102 struct cci_pmu_hw_events {
103 	struct perf_event *events[CCI_PMU_MAX_HW_EVENTS];
104 	unsigned long used_mask[BITS_TO_LONGS(CCI_PMU_MAX_HW_EVENTS)];
105 	raw_spinlock_t pmu_lock;
106 };
107 
108 struct cci_pmu_model {
109 	char *name;
110 	struct event_range event_ranges[CCI_IF_MAX];
111 };
112 
113 static struct cci_pmu_model cci_pmu_models[];
114 
115 struct cci_pmu {
116 	void __iomem *base;
117 	struct pmu pmu;
118 	int nr_irqs;
119 	int irqs[CCI_PMU_MAX_HW_EVENTS];
120 	unsigned long active_irqs;
121 	const struct cci_pmu_model *model;
122 	struct cci_pmu_hw_events hw_events;
123 	struct platform_device *plat_device;
124 	int num_events;
125 	atomic_t active_events;
126 	struct mutex reserve_mutex;
127 	cpumask_t cpus;
128 };
129 static struct cci_pmu *pmu;
130 
131 #define to_cci_pmu(c)	(container_of(c, struct cci_pmu, pmu))
132 
133 /* Port ids */
134 #define CCI_PORT_S0	0
135 #define CCI_PORT_S1	1
136 #define CCI_PORT_S2	2
137 #define CCI_PORT_S3	3
138 #define CCI_PORT_S4	4
139 #define CCI_PORT_M0	5
140 #define CCI_PORT_M1	6
141 #define CCI_PORT_M2	7
142 
143 #define CCI_REV_R0		0
144 #define CCI_REV_R1		1
145 #define CCI_REV_R1_PX		5
146 
147 /*
148  * Instead of an event id to monitor CCI cycles, a dedicated counter is
149  * provided. Use 0xff to represent CCI cycles and hope that no future revisions
150  * make use of this event in hardware.
151  */
152 enum cci400_perf_events {
153 	CCI_PMU_CYCLES = 0xff
154 };
155 
156 #define CCI_PMU_CYCLE_CNTR_IDX		0
157 #define CCI_PMU_CNTR0_IDX		1
158 #define CCI_PMU_CNTR_LAST(cci_pmu)	(CCI_PMU_CYCLE_CNTR_IDX + cci_pmu->num_events - 1)
159 
160 /*
161  * CCI PMU event id is an 8-bit value made of two parts - bits 7:5 for one of 8
162  * ports and bits 4:0 are event codes. There are different event codes
163  * associated with each port type.
164  *
165  * Additionally, the range of events associated with the port types changed
166  * between Rev0 and Rev1.
167  *
168  * The constants below define the range of valid codes for each port type for
169  * the different revisions and are used to validate the event to be monitored.
170  */
171 
172 #define CCI_REV_R0_SLAVE_PORT_MIN_EV	0x00
173 #define CCI_REV_R0_SLAVE_PORT_MAX_EV	0x13
174 #define CCI_REV_R0_MASTER_PORT_MIN_EV	0x14
175 #define CCI_REV_R0_MASTER_PORT_MAX_EV	0x1a
176 
177 #define CCI_REV_R1_SLAVE_PORT_MIN_EV	0x00
178 #define CCI_REV_R1_SLAVE_PORT_MAX_EV	0x14
179 #define CCI_REV_R1_MASTER_PORT_MIN_EV	0x00
180 #define CCI_REV_R1_MASTER_PORT_MAX_EV	0x11
181 
182 static int pmu_validate_hw_event(unsigned long hw_event)
183 {
184 	u8 ev_source = CCI_PMU_EVENT_SOURCE(hw_event);
185 	u8 ev_code = CCI_PMU_EVENT_CODE(hw_event);
186 	int if_type;
187 
188 	if (hw_event & ~CCI_PMU_EVENT_MASK)
189 		return -ENOENT;
190 
191 	switch (ev_source) {
192 	case CCI_PORT_S0:
193 	case CCI_PORT_S1:
194 	case CCI_PORT_S2:
195 	case CCI_PORT_S3:
196 	case CCI_PORT_S4:
197 		/* Slave Interface */
198 		if_type = CCI_IF_SLAVE;
199 		break;
200 	case CCI_PORT_M0:
201 	case CCI_PORT_M1:
202 	case CCI_PORT_M2:
203 		/* Master Interface */
204 		if_type = CCI_IF_MASTER;
205 		break;
206 	default:
207 		return -ENOENT;
208 	}
209 
210 	if (ev_code >= pmu->model->event_ranges[if_type].min &&
211 		ev_code <= pmu->model->event_ranges[if_type].max)
212 		return hw_event;
213 
214 	return -ENOENT;
215 }
216 
217 static int probe_cci_revision(void)
218 {
219 	int rev;
220 	rev = readl_relaxed(cci_ctrl_base + CCI_PID2) & CCI_PID2_REV_MASK;
221 	rev >>= CCI_PID2_REV_SHIFT;
222 
223 	if (rev < CCI_REV_R1_PX)
224 		return CCI_REV_R0;
225 	else
226 		return CCI_REV_R1;
227 }
228 
229 static const struct cci_pmu_model *probe_cci_model(struct platform_device *pdev)
230 {
231 	if (platform_has_secure_cci_access())
232 		return &cci_pmu_models[probe_cci_revision()];
233 	return NULL;
234 }
235 
236 static int pmu_is_valid_counter(struct cci_pmu *cci_pmu, int idx)
237 {
238 	return CCI_PMU_CYCLE_CNTR_IDX <= idx &&
239 		idx <= CCI_PMU_CNTR_LAST(cci_pmu);
240 }
241 
242 static u32 pmu_read_register(int idx, unsigned int offset)
243 {
244 	return readl_relaxed(pmu->base + CCI_PMU_CNTR_BASE(idx) + offset);
245 }
246 
247 static void pmu_write_register(u32 value, int idx, unsigned int offset)
248 {
249 	return writel_relaxed(value, pmu->base + CCI_PMU_CNTR_BASE(idx) + offset);
250 }
251 
252 static void pmu_disable_counter(int idx)
253 {
254 	pmu_write_register(0, idx, CCI_PMU_CNTR_CTRL);
255 }
256 
257 static void pmu_enable_counter(int idx)
258 {
259 	pmu_write_register(1, idx, CCI_PMU_CNTR_CTRL);
260 }
261 
262 static void pmu_set_event(int idx, unsigned long event)
263 {
264 	pmu_write_register(event, idx, CCI_PMU_EVT_SEL);
265 }
266 
267 static u32 pmu_get_max_counters(void)
268 {
269 	u32 n_cnts = (readl_relaxed(cci_ctrl_base + CCI_PMCR) &
270 		      CCI_PMCR_NCNT_MASK) >> CCI_PMCR_NCNT_SHIFT;
271 
272 	/* add 1 for cycle counter */
273 	return n_cnts + 1;
274 }
275 
276 static int pmu_get_event_idx(struct cci_pmu_hw_events *hw, struct perf_event *event)
277 {
278 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
279 	struct hw_perf_event *hw_event = &event->hw;
280 	unsigned long cci_event = hw_event->config_base;
281 	int idx;
282 
283 	if (cci_event == CCI_PMU_CYCLES) {
284 		if (test_and_set_bit(CCI_PMU_CYCLE_CNTR_IDX, hw->used_mask))
285 			return -EAGAIN;
286 
287 		return CCI_PMU_CYCLE_CNTR_IDX;
288 	}
289 
290 	for (idx = CCI_PMU_CNTR0_IDX; idx <= CCI_PMU_CNTR_LAST(cci_pmu); ++idx)
291 		if (!test_and_set_bit(idx, hw->used_mask))
292 			return idx;
293 
294 	/* No counters available */
295 	return -EAGAIN;
296 }
297 
298 static int pmu_map_event(struct perf_event *event)
299 {
300 	int mapping;
301 	unsigned long config = event->attr.config;
302 
303 	if (event->attr.type < PERF_TYPE_MAX)
304 		return -ENOENT;
305 
306 	if (config == CCI_PMU_CYCLES)
307 		mapping = config;
308 	else
309 		mapping = pmu_validate_hw_event(config);
310 
311 	return mapping;
312 }
313 
314 static int pmu_request_irq(struct cci_pmu *cci_pmu, irq_handler_t handler)
315 {
316 	int i;
317 	struct platform_device *pmu_device = cci_pmu->plat_device;
318 
319 	if (unlikely(!pmu_device))
320 		return -ENODEV;
321 
322 	if (pmu->nr_irqs < 1) {
323 		dev_err(&pmu_device->dev, "no irqs for CCI PMUs defined\n");
324 		return -ENODEV;
325 	}
326 
327 	/*
328 	 * Register all available CCI PMU interrupts. In the interrupt handler
329 	 * we iterate over the counters checking for interrupt source (the
330 	 * overflowing counter) and clear it.
331 	 *
332 	 * This should allow handling of non-unique interrupt for the counters.
333 	 */
334 	for (i = 0; i < pmu->nr_irqs; i++) {
335 		int err = request_irq(pmu->irqs[i], handler, IRQF_SHARED,
336 				"arm-cci-pmu", cci_pmu);
337 		if (err) {
338 			dev_err(&pmu_device->dev, "unable to request IRQ%d for ARM CCI PMU counters\n",
339 				pmu->irqs[i]);
340 			return err;
341 		}
342 
343 		set_bit(i, &pmu->active_irqs);
344 	}
345 
346 	return 0;
347 }
348 
349 static void pmu_free_irq(struct cci_pmu *cci_pmu)
350 {
351 	int i;
352 
353 	for (i = 0; i < pmu->nr_irqs; i++) {
354 		if (!test_and_clear_bit(i, &pmu->active_irqs))
355 			continue;
356 
357 		free_irq(pmu->irqs[i], cci_pmu);
358 	}
359 }
360 
361 static u32 pmu_read_counter(struct perf_event *event)
362 {
363 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
364 	struct hw_perf_event *hw_counter = &event->hw;
365 	int idx = hw_counter->idx;
366 	u32 value;
367 
368 	if (unlikely(!pmu_is_valid_counter(cci_pmu, idx))) {
369 		dev_err(&cci_pmu->plat_device->dev, "Invalid CCI PMU counter %d\n", idx);
370 		return 0;
371 	}
372 	value = pmu_read_register(idx, CCI_PMU_CNTR);
373 
374 	return value;
375 }
376 
377 static void pmu_write_counter(struct perf_event *event, u32 value)
378 {
379 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
380 	struct hw_perf_event *hw_counter = &event->hw;
381 	int idx = hw_counter->idx;
382 
383 	if (unlikely(!pmu_is_valid_counter(cci_pmu, idx)))
384 		dev_err(&cci_pmu->plat_device->dev, "Invalid CCI PMU counter %d\n", idx);
385 	else
386 		pmu_write_register(value, idx, CCI_PMU_CNTR);
387 }
388 
389 static u64 pmu_event_update(struct perf_event *event)
390 {
391 	struct hw_perf_event *hwc = &event->hw;
392 	u64 delta, prev_raw_count, new_raw_count;
393 
394 	do {
395 		prev_raw_count = local64_read(&hwc->prev_count);
396 		new_raw_count = pmu_read_counter(event);
397 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
398 		 new_raw_count) != prev_raw_count);
399 
400 	delta = (new_raw_count - prev_raw_count) & CCI_PMU_CNTR_MASK;
401 
402 	local64_add(delta, &event->count);
403 
404 	return new_raw_count;
405 }
406 
407 static void pmu_read(struct perf_event *event)
408 {
409 	pmu_event_update(event);
410 }
411 
412 void pmu_event_set_period(struct perf_event *event)
413 {
414 	struct hw_perf_event *hwc = &event->hw;
415 	/*
416 	 * The CCI PMU counters have a period of 2^32. To account for the
417 	 * possiblity of extreme interrupt latency we program for a period of
418 	 * half that. Hopefully we can handle the interrupt before another 2^31
419 	 * events occur and the counter overtakes its previous value.
420 	 */
421 	u64 val = 1ULL << 31;
422 	local64_set(&hwc->prev_count, val);
423 	pmu_write_counter(event, val);
424 }
425 
426 static irqreturn_t pmu_handle_irq(int irq_num, void *dev)
427 {
428 	unsigned long flags;
429 	struct cci_pmu *cci_pmu = dev;
430 	struct cci_pmu_hw_events *events = &pmu->hw_events;
431 	int idx, handled = IRQ_NONE;
432 
433 	raw_spin_lock_irqsave(&events->pmu_lock, flags);
434 	/*
435 	 * Iterate over counters and update the corresponding perf events.
436 	 * This should work regardless of whether we have per-counter overflow
437 	 * interrupt or a combined overflow interrupt.
438 	 */
439 	for (idx = CCI_PMU_CYCLE_CNTR_IDX; idx <= CCI_PMU_CNTR_LAST(cci_pmu); idx++) {
440 		struct perf_event *event = events->events[idx];
441 		struct hw_perf_event *hw_counter;
442 
443 		if (!event)
444 			continue;
445 
446 		hw_counter = &event->hw;
447 
448 		/* Did this counter overflow? */
449 		if (!(pmu_read_register(idx, CCI_PMU_OVRFLW) &
450 		      CCI_PMU_OVRFLW_FLAG))
451 			continue;
452 
453 		pmu_write_register(CCI_PMU_OVRFLW_FLAG, idx, CCI_PMU_OVRFLW);
454 
455 		pmu_event_update(event);
456 		pmu_event_set_period(event);
457 		handled = IRQ_HANDLED;
458 	}
459 	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
460 
461 	return IRQ_RETVAL(handled);
462 }
463 
464 static int cci_pmu_get_hw(struct cci_pmu *cci_pmu)
465 {
466 	int ret = pmu_request_irq(cci_pmu, pmu_handle_irq);
467 	if (ret) {
468 		pmu_free_irq(cci_pmu);
469 		return ret;
470 	}
471 	return 0;
472 }
473 
474 static void cci_pmu_put_hw(struct cci_pmu *cci_pmu)
475 {
476 	pmu_free_irq(cci_pmu);
477 }
478 
479 static void hw_perf_event_destroy(struct perf_event *event)
480 {
481 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
482 	atomic_t *active_events = &cci_pmu->active_events;
483 	struct mutex *reserve_mutex = &cci_pmu->reserve_mutex;
484 
485 	if (atomic_dec_and_mutex_lock(active_events, reserve_mutex)) {
486 		cci_pmu_put_hw(cci_pmu);
487 		mutex_unlock(reserve_mutex);
488 	}
489 }
490 
491 static void cci_pmu_enable(struct pmu *pmu)
492 {
493 	struct cci_pmu *cci_pmu = to_cci_pmu(pmu);
494 	struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
495 	int enabled = bitmap_weight(hw_events->used_mask, cci_pmu->num_events);
496 	unsigned long flags;
497 	u32 val;
498 
499 	if (!enabled)
500 		return;
501 
502 	raw_spin_lock_irqsave(&hw_events->pmu_lock, flags);
503 
504 	/* Enable all the PMU counters. */
505 	val = readl_relaxed(cci_ctrl_base + CCI_PMCR) | CCI_PMCR_CEN;
506 	writel(val, cci_ctrl_base + CCI_PMCR);
507 	raw_spin_unlock_irqrestore(&hw_events->pmu_lock, flags);
508 
509 }
510 
511 static void cci_pmu_disable(struct pmu *pmu)
512 {
513 	struct cci_pmu *cci_pmu = to_cci_pmu(pmu);
514 	struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
515 	unsigned long flags;
516 	u32 val;
517 
518 	raw_spin_lock_irqsave(&hw_events->pmu_lock, flags);
519 
520 	/* Disable all the PMU counters. */
521 	val = readl_relaxed(cci_ctrl_base + CCI_PMCR) & ~CCI_PMCR_CEN;
522 	writel(val, cci_ctrl_base + CCI_PMCR);
523 	raw_spin_unlock_irqrestore(&hw_events->pmu_lock, flags);
524 }
525 
526 static void cci_pmu_start(struct perf_event *event, int pmu_flags)
527 {
528 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
529 	struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
530 	struct hw_perf_event *hwc = &event->hw;
531 	int idx = hwc->idx;
532 	unsigned long flags;
533 
534 	/*
535 	 * To handle interrupt latency, we always reprogram the period
536 	 * regardlesss of PERF_EF_RELOAD.
537 	 */
538 	if (pmu_flags & PERF_EF_RELOAD)
539 		WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
540 
541 	hwc->state = 0;
542 
543 	if (unlikely(!pmu_is_valid_counter(cci_pmu, idx))) {
544 		dev_err(&cci_pmu->plat_device->dev, "Invalid CCI PMU counter %d\n", idx);
545 		return;
546 	}
547 
548 	raw_spin_lock_irqsave(&hw_events->pmu_lock, flags);
549 
550 	/* Configure the event to count, unless you are counting cycles */
551 	if (idx != CCI_PMU_CYCLE_CNTR_IDX)
552 		pmu_set_event(idx, hwc->config_base);
553 
554 	pmu_event_set_period(event);
555 	pmu_enable_counter(idx);
556 
557 	raw_spin_unlock_irqrestore(&hw_events->pmu_lock, flags);
558 }
559 
560 static void cci_pmu_stop(struct perf_event *event, int pmu_flags)
561 {
562 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
563 	struct hw_perf_event *hwc = &event->hw;
564 	int idx = hwc->idx;
565 
566 	if (hwc->state & PERF_HES_STOPPED)
567 		return;
568 
569 	if (unlikely(!pmu_is_valid_counter(cci_pmu, idx))) {
570 		dev_err(&cci_pmu->plat_device->dev, "Invalid CCI PMU counter %d\n", idx);
571 		return;
572 	}
573 
574 	/*
575 	 * We always reprogram the counter, so ignore PERF_EF_UPDATE. See
576 	 * cci_pmu_start()
577 	 */
578 	pmu_disable_counter(idx);
579 	pmu_event_update(event);
580 	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
581 }
582 
583 static int cci_pmu_add(struct perf_event *event, int flags)
584 {
585 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
586 	struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
587 	struct hw_perf_event *hwc = &event->hw;
588 	int idx;
589 	int err = 0;
590 
591 	perf_pmu_disable(event->pmu);
592 
593 	/* If we don't have a space for the counter then finish early. */
594 	idx = pmu_get_event_idx(hw_events, event);
595 	if (idx < 0) {
596 		err = idx;
597 		goto out;
598 	}
599 
600 	event->hw.idx = idx;
601 	hw_events->events[idx] = event;
602 
603 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
604 	if (flags & PERF_EF_START)
605 		cci_pmu_start(event, PERF_EF_RELOAD);
606 
607 	/* Propagate our changes to the userspace mapping. */
608 	perf_event_update_userpage(event);
609 
610 out:
611 	perf_pmu_enable(event->pmu);
612 	return err;
613 }
614 
615 static void cci_pmu_del(struct perf_event *event, int flags)
616 {
617 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
618 	struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
619 	struct hw_perf_event *hwc = &event->hw;
620 	int idx = hwc->idx;
621 
622 	cci_pmu_stop(event, PERF_EF_UPDATE);
623 	hw_events->events[idx] = NULL;
624 	clear_bit(idx, hw_events->used_mask);
625 
626 	perf_event_update_userpage(event);
627 }
628 
629 static int
630 validate_event(struct pmu *cci_pmu,
631                struct cci_pmu_hw_events *hw_events,
632                struct perf_event *event)
633 {
634 	if (is_software_event(event))
635 		return 1;
636 
637 	/*
638 	 * Reject groups spanning multiple HW PMUs (e.g. CPU + CCI). The
639 	 * core perf code won't check that the pmu->ctx == leader->ctx
640 	 * until after pmu->event_init(event).
641 	 */
642 	if (event->pmu != cci_pmu)
643 		return 0;
644 
645 	if (event->state < PERF_EVENT_STATE_OFF)
646 		return 1;
647 
648 	if (event->state == PERF_EVENT_STATE_OFF && !event->attr.enable_on_exec)
649 		return 1;
650 
651 	return pmu_get_event_idx(hw_events, event) >= 0;
652 }
653 
654 static int
655 validate_group(struct perf_event *event)
656 {
657 	struct perf_event *sibling, *leader = event->group_leader;
658 	struct cci_pmu_hw_events fake_pmu = {
659 		/*
660 		 * Initialise the fake PMU. We only need to populate the
661 		 * used_mask for the purposes of validation.
662 		 */
663 		.used_mask = CPU_BITS_NONE,
664 	};
665 
666 	if (!validate_event(event->pmu, &fake_pmu, leader))
667 		return -EINVAL;
668 
669 	list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
670 		if (!validate_event(event->pmu, &fake_pmu, sibling))
671 			return -EINVAL;
672 	}
673 
674 	if (!validate_event(event->pmu, &fake_pmu, event))
675 		return -EINVAL;
676 
677 	return 0;
678 }
679 
680 static int
681 __hw_perf_event_init(struct perf_event *event)
682 {
683 	struct hw_perf_event *hwc = &event->hw;
684 	int mapping;
685 
686 	mapping = pmu_map_event(event);
687 
688 	if (mapping < 0) {
689 		pr_debug("event %x:%llx not supported\n", event->attr.type,
690 			 event->attr.config);
691 		return mapping;
692 	}
693 
694 	/*
695 	 * We don't assign an index until we actually place the event onto
696 	 * hardware. Use -1 to signify that we haven't decided where to put it
697 	 * yet.
698 	 */
699 	hwc->idx		= -1;
700 	hwc->config_base	= 0;
701 	hwc->config		= 0;
702 	hwc->event_base		= 0;
703 
704 	/*
705 	 * Store the event encoding into the config_base field.
706 	 */
707 	hwc->config_base	    |= (unsigned long)mapping;
708 
709 	/*
710 	 * Limit the sample_period to half of the counter width. That way, the
711 	 * new counter value is far less likely to overtake the previous one
712 	 * unless you have some serious IRQ latency issues.
713 	 */
714 	hwc->sample_period  = CCI_PMU_CNTR_MASK >> 1;
715 	hwc->last_period    = hwc->sample_period;
716 	local64_set(&hwc->period_left, hwc->sample_period);
717 
718 	if (event->group_leader != event) {
719 		if (validate_group(event) != 0)
720 			return -EINVAL;
721 	}
722 
723 	return 0;
724 }
725 
726 static int cci_pmu_event_init(struct perf_event *event)
727 {
728 	struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu);
729 	atomic_t *active_events = &cci_pmu->active_events;
730 	int err = 0;
731 	int cpu;
732 
733 	if (event->attr.type != event->pmu->type)
734 		return -ENOENT;
735 
736 	/* Shared by all CPUs, no meaningful state to sample */
737 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
738 		return -EOPNOTSUPP;
739 
740 	/* We have no filtering of any kind */
741 	if (event->attr.exclude_user	||
742 	    event->attr.exclude_kernel	||
743 	    event->attr.exclude_hv	||
744 	    event->attr.exclude_idle	||
745 	    event->attr.exclude_host	||
746 	    event->attr.exclude_guest)
747 		return -EINVAL;
748 
749 	/*
750 	 * Following the example set by other "uncore" PMUs, we accept any CPU
751 	 * and rewrite its affinity dynamically rather than having perf core
752 	 * handle cpu == -1 and pid == -1 for this case.
753 	 *
754 	 * The perf core will pin online CPUs for the duration of this call and
755 	 * the event being installed into its context, so the PMU's CPU can't
756 	 * change under our feet.
757 	 */
758 	cpu = cpumask_first(&cci_pmu->cpus);
759 	if (event->cpu < 0 || cpu < 0)
760 		return -EINVAL;
761 	event->cpu = cpu;
762 
763 	event->destroy = hw_perf_event_destroy;
764 	if (!atomic_inc_not_zero(active_events)) {
765 		mutex_lock(&cci_pmu->reserve_mutex);
766 		if (atomic_read(active_events) == 0)
767 			err = cci_pmu_get_hw(cci_pmu);
768 		if (!err)
769 			atomic_inc(active_events);
770 		mutex_unlock(&cci_pmu->reserve_mutex);
771 	}
772 	if (err)
773 		return err;
774 
775 	err = __hw_perf_event_init(event);
776 	if (err)
777 		hw_perf_event_destroy(event);
778 
779 	return err;
780 }
781 
782 static ssize_t pmu_attr_cpumask_show(struct device *dev,
783 				     struct device_attribute *attr, char *buf)
784 {
785 	int n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
786 			  cpumask_pr_args(&pmu->cpus));
787 	buf[n++] = '\n';
788 	buf[n] = '\0';
789 	return n;
790 }
791 
792 static DEVICE_ATTR(cpumask, S_IRUGO, pmu_attr_cpumask_show, NULL);
793 
794 static struct attribute *pmu_attrs[] = {
795 	&dev_attr_cpumask.attr,
796 	NULL,
797 };
798 
799 static struct attribute_group pmu_attr_group = {
800 	.attrs = pmu_attrs,
801 };
802 
803 static const struct attribute_group *pmu_attr_groups[] = {
804 	&pmu_attr_group,
805 	NULL
806 };
807 
808 static int cci_pmu_init(struct cci_pmu *cci_pmu, struct platform_device *pdev)
809 {
810 	char *name = cci_pmu->model->name;
811 	cci_pmu->pmu = (struct pmu) {
812 		.name		= cci_pmu->model->name,
813 		.task_ctx_nr	= perf_invalid_context,
814 		.pmu_enable	= cci_pmu_enable,
815 		.pmu_disable	= cci_pmu_disable,
816 		.event_init	= cci_pmu_event_init,
817 		.add		= cci_pmu_add,
818 		.del		= cci_pmu_del,
819 		.start		= cci_pmu_start,
820 		.stop		= cci_pmu_stop,
821 		.read		= pmu_read,
822 		.attr_groups	= pmu_attr_groups,
823 	};
824 
825 	cci_pmu->plat_device = pdev;
826 	cci_pmu->num_events = pmu_get_max_counters();
827 
828 	return perf_pmu_register(&cci_pmu->pmu, name, -1);
829 }
830 
831 static int cci_pmu_cpu_notifier(struct notifier_block *self,
832 				unsigned long action, void *hcpu)
833 {
834 	unsigned int cpu = (long)hcpu;
835 	unsigned int target;
836 
837 	switch (action & ~CPU_TASKS_FROZEN) {
838 	case CPU_DOWN_PREPARE:
839 		if (!cpumask_test_and_clear_cpu(cpu, &pmu->cpus))
840 			break;
841 		target = cpumask_any_but(cpu_online_mask, cpu);
842 		if (target < 0) // UP, last CPU
843 			break;
844 		/*
845 		 * TODO: migrate context once core races on event->ctx have
846 		 * been fixed.
847 		 */
848 		cpumask_set_cpu(target, &pmu->cpus);
849 	default:
850 		break;
851 	}
852 
853 	return NOTIFY_OK;
854 }
855 
856 static struct notifier_block cci_pmu_cpu_nb = {
857 	.notifier_call	= cci_pmu_cpu_notifier,
858 	/*
859 	 * to migrate uncore events, our notifier should be executed
860 	 * before perf core's notifier.
861 	 */
862 	.priority	= CPU_PRI_PERF + 1,
863 };
864 
865 static struct cci_pmu_model cci_pmu_models[] = {
866 	[CCI_REV_R0] = {
867 		.name = "CCI_400",
868 		.event_ranges = {
869 			[CCI_IF_SLAVE] = {
870 				CCI_REV_R0_SLAVE_PORT_MIN_EV,
871 				CCI_REV_R0_SLAVE_PORT_MAX_EV,
872 			},
873 			[CCI_IF_MASTER] = {
874 				CCI_REV_R0_MASTER_PORT_MIN_EV,
875 				CCI_REV_R0_MASTER_PORT_MAX_EV,
876 			},
877 		},
878 	},
879 	[CCI_REV_R1] = {
880 		.name = "CCI_400_r1",
881 		.event_ranges = {
882 			[CCI_IF_SLAVE] = {
883 				CCI_REV_R1_SLAVE_PORT_MIN_EV,
884 				CCI_REV_R1_SLAVE_PORT_MAX_EV,
885 			},
886 			[CCI_IF_MASTER] = {
887 				CCI_REV_R1_MASTER_PORT_MIN_EV,
888 				CCI_REV_R1_MASTER_PORT_MAX_EV,
889 			},
890 		},
891 	},
892 };
893 
894 static const struct of_device_id arm_cci_pmu_matches[] = {
895 	{
896 		.compatible = "arm,cci-400-pmu",
897 		.data	= NULL,
898 	},
899 	{
900 		.compatible = "arm,cci-400-pmu,r0",
901 		.data	= &cci_pmu_models[CCI_REV_R0],
902 	},
903 	{
904 		.compatible = "arm,cci-400-pmu,r1",
905 		.data	= &cci_pmu_models[CCI_REV_R1],
906 	},
907 	{},
908 };
909 
910 static inline const struct cci_pmu_model *get_cci_model(struct platform_device *pdev)
911 {
912 	const struct of_device_id *match = of_match_node(arm_cci_pmu_matches,
913 							pdev->dev.of_node);
914 	if (!match)
915 		return NULL;
916 	if (match->data)
917 		return match->data;
918 
919 	dev_warn(&pdev->dev, "DEPRECATED compatible property,"
920 			 "requires secure access to CCI registers");
921 	return probe_cci_model(pdev);
922 }
923 
924 static bool is_duplicate_irq(int irq, int *irqs, int nr_irqs)
925 {
926 	int i;
927 
928 	for (i = 0; i < nr_irqs; i++)
929 		if (irq == irqs[i])
930 			return true;
931 
932 	return false;
933 }
934 
935 static int cci_pmu_probe(struct platform_device *pdev)
936 {
937 	struct resource *res;
938 	int i, ret, irq;
939 	const struct cci_pmu_model *model;
940 
941 	model = get_cci_model(pdev);
942 	if (!model) {
943 		dev_warn(&pdev->dev, "CCI PMU version not supported\n");
944 		return -ENODEV;
945 	}
946 
947 	pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
948 	if (!pmu)
949 		return -ENOMEM;
950 
951 	pmu->model = model;
952 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
953 	pmu->base = devm_ioremap_resource(&pdev->dev, res);
954 	if (IS_ERR(pmu->base))
955 		return -ENOMEM;
956 
957 	/*
958 	 * CCI PMU has 5 overflow signals - one per counter; but some may be tied
959 	 * together to a common interrupt.
960 	 */
961 	pmu->nr_irqs = 0;
962 	for (i = 0; i < CCI_PMU_MAX_HW_EVENTS; i++) {
963 		irq = platform_get_irq(pdev, i);
964 		if (irq < 0)
965 			break;
966 
967 		if (is_duplicate_irq(irq, pmu->irqs, pmu->nr_irqs))
968 			continue;
969 
970 		pmu->irqs[pmu->nr_irqs++] = irq;
971 	}
972 
973 	/*
974 	 * Ensure that the device tree has as many interrupts as the number
975 	 * of counters.
976 	 */
977 	if (i < CCI_PMU_MAX_HW_EVENTS) {
978 		dev_warn(&pdev->dev, "In-correct number of interrupts: %d, should be %d\n",
979 			i, CCI_PMU_MAX_HW_EVENTS);
980 		return -EINVAL;
981 	}
982 
983 	raw_spin_lock_init(&pmu->hw_events.pmu_lock);
984 	mutex_init(&pmu->reserve_mutex);
985 	atomic_set(&pmu->active_events, 0);
986 	cpumask_set_cpu(smp_processor_id(), &pmu->cpus);
987 
988 	ret = register_cpu_notifier(&cci_pmu_cpu_nb);
989 	if (ret)
990 		return ret;
991 
992 	ret = cci_pmu_init(pmu, pdev);
993 	if (ret)
994 		return ret;
995 
996 	pr_info("ARM %s PMU driver probed", pmu->model->name);
997 	return 0;
998 }
999 
1000 static int cci_platform_probe(struct platform_device *pdev)
1001 {
1002 	if (!cci_probed())
1003 		return -ENODEV;
1004 
1005 	return of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
1006 }
1007 
1008 static struct platform_driver cci_pmu_driver = {
1009 	.driver = {
1010 		   .name = DRIVER_NAME_PMU,
1011 		   .of_match_table = arm_cci_pmu_matches,
1012 		  },
1013 	.probe = cci_pmu_probe,
1014 };
1015 
1016 static struct platform_driver cci_platform_driver = {
1017 	.driver = {
1018 		   .name = DRIVER_NAME,
1019 		   .of_match_table = arm_cci_matches,
1020 		  },
1021 	.probe = cci_platform_probe,
1022 };
1023 
1024 static int __init cci_platform_init(void)
1025 {
1026 	int ret;
1027 
1028 	ret = platform_driver_register(&cci_pmu_driver);
1029 	if (ret)
1030 		return ret;
1031 
1032 	return platform_driver_register(&cci_platform_driver);
1033 }
1034 
1035 #else /* !CONFIG_ARM_CCI400_PMU */
1036 
1037 static int __init cci_platform_init(void)
1038 {
1039 	return 0;
1040 }
1041 
1042 #endif /* CONFIG_ARM_CCI400_PMU */
1043 
1044 #ifdef CONFIG_ARM_CCI400_PORT_CTRL
1045 
1046 #define CCI_PORT_CTRL		0x0
1047 #define CCI_CTRL_STATUS		0xc
1048 
1049 #define CCI_ENABLE_SNOOP_REQ	0x1
1050 #define CCI_ENABLE_DVM_REQ	0x2
1051 #define CCI_ENABLE_REQ		(CCI_ENABLE_SNOOP_REQ | CCI_ENABLE_DVM_REQ)
1052 
1053 enum cci_ace_port_type {
1054 	ACE_INVALID_PORT = 0x0,
1055 	ACE_PORT,
1056 	ACE_LITE_PORT,
1057 };
1058 
1059 struct cci_ace_port {
1060 	void __iomem *base;
1061 	unsigned long phys;
1062 	enum cci_ace_port_type type;
1063 	struct device_node *dn;
1064 };
1065 
1066 static struct cci_ace_port *ports;
1067 static unsigned int nb_cci_ports;
1068 
1069 struct cpu_port {
1070 	u64 mpidr;
1071 	u32 port;
1072 };
1073 
1074 /*
1075  * Use the port MSB as valid flag, shift can be made dynamic
1076  * by computing number of bits required for port indexes.
1077  * Code disabling CCI cpu ports runs with D-cache invalidated
1078  * and SCTLR bit clear so data accesses must be kept to a minimum
1079  * to improve performance; for now shift is left static to
1080  * avoid one more data access while disabling the CCI port.
1081  */
1082 #define PORT_VALID_SHIFT	31
1083 #define PORT_VALID		(0x1 << PORT_VALID_SHIFT)
1084 
1085 static inline void init_cpu_port(struct cpu_port *port, u32 index, u64 mpidr)
1086 {
1087 	port->port = PORT_VALID | index;
1088 	port->mpidr = mpidr;
1089 }
1090 
1091 static inline bool cpu_port_is_valid(struct cpu_port *port)
1092 {
1093 	return !!(port->port & PORT_VALID);
1094 }
1095 
1096 static inline bool cpu_port_match(struct cpu_port *port, u64 mpidr)
1097 {
1098 	return port->mpidr == (mpidr & MPIDR_HWID_BITMASK);
1099 }
1100 
1101 static struct cpu_port cpu_port[NR_CPUS];
1102 
1103 /**
1104  * __cci_ace_get_port - Function to retrieve the port index connected to
1105  *			a cpu or device.
1106  *
1107  * @dn: device node of the device to look-up
1108  * @type: port type
1109  *
1110  * Return value:
1111  *	- CCI port index if success
1112  *	- -ENODEV if failure
1113  */
1114 static int __cci_ace_get_port(struct device_node *dn, int type)
1115 {
1116 	int i;
1117 	bool ace_match;
1118 	struct device_node *cci_portn;
1119 
1120 	cci_portn = of_parse_phandle(dn, "cci-control-port", 0);
1121 	for (i = 0; i < nb_cci_ports; i++) {
1122 		ace_match = ports[i].type == type;
1123 		if (ace_match && cci_portn == ports[i].dn)
1124 			return i;
1125 	}
1126 	return -ENODEV;
1127 }
1128 
1129 int cci_ace_get_port(struct device_node *dn)
1130 {
1131 	return __cci_ace_get_port(dn, ACE_LITE_PORT);
1132 }
1133 EXPORT_SYMBOL_GPL(cci_ace_get_port);
1134 
1135 static void cci_ace_init_ports(void)
1136 {
1137 	int port, cpu;
1138 	struct device_node *cpun;
1139 
1140 	/*
1141 	 * Port index look-up speeds up the function disabling ports by CPU,
1142 	 * since the logical to port index mapping is done once and does
1143 	 * not change after system boot.
1144 	 * The stashed index array is initialized for all possible CPUs
1145 	 * at probe time.
1146 	 */
1147 	for_each_possible_cpu(cpu) {
1148 		/* too early to use cpu->of_node */
1149 		cpun = of_get_cpu_node(cpu, NULL);
1150 
1151 		if (WARN(!cpun, "Missing cpu device node\n"))
1152 			continue;
1153 
1154 		port = __cci_ace_get_port(cpun, ACE_PORT);
1155 		if (port < 0)
1156 			continue;
1157 
1158 		init_cpu_port(&cpu_port[cpu], port, cpu_logical_map(cpu));
1159 	}
1160 
1161 	for_each_possible_cpu(cpu) {
1162 		WARN(!cpu_port_is_valid(&cpu_port[cpu]),
1163 			"CPU %u does not have an associated CCI port\n",
1164 			cpu);
1165 	}
1166 }
1167 /*
1168  * Functions to enable/disable a CCI interconnect slave port
1169  *
1170  * They are called by low-level power management code to disable slave
1171  * interfaces snoops and DVM broadcast.
1172  * Since they may execute with cache data allocation disabled and
1173  * after the caches have been cleaned and invalidated the functions provide
1174  * no explicit locking since they may run with D-cache disabled, so normal
1175  * cacheable kernel locks based on ldrex/strex may not work.
1176  * Locking has to be provided by BSP implementations to ensure proper
1177  * operations.
1178  */
1179 
1180 /**
1181  * cci_port_control() - function to control a CCI port
1182  *
1183  * @port: index of the port to setup
1184  * @enable: if true enables the port, if false disables it
1185  */
1186 static void notrace cci_port_control(unsigned int port, bool enable)
1187 {
1188 	void __iomem *base = ports[port].base;
1189 
1190 	writel_relaxed(enable ? CCI_ENABLE_REQ : 0, base + CCI_PORT_CTRL);
1191 	/*
1192 	 * This function is called from power down procedures
1193 	 * and must not execute any instruction that might
1194 	 * cause the processor to be put in a quiescent state
1195 	 * (eg wfi). Hence, cpu_relax() can not be added to this
1196 	 * read loop to optimize power, since it might hide possibly
1197 	 * disruptive operations.
1198 	 */
1199 	while (readl_relaxed(cci_ctrl_base + CCI_CTRL_STATUS) & 0x1)
1200 			;
1201 }
1202 
1203 /**
1204  * cci_disable_port_by_cpu() - function to disable a CCI port by CPU
1205  *			       reference
1206  *
1207  * @mpidr: mpidr of the CPU whose CCI port should be disabled
1208  *
1209  * Disabling a CCI port for a CPU implies disabling the CCI port
1210  * controlling that CPU cluster. Code disabling CPU CCI ports
1211  * must make sure that the CPU running the code is the last active CPU
1212  * in the cluster ie all other CPUs are quiescent in a low power state.
1213  *
1214  * Return:
1215  *	0 on success
1216  *	-ENODEV on port look-up failure
1217  */
1218 int notrace cci_disable_port_by_cpu(u64 mpidr)
1219 {
1220 	int cpu;
1221 	bool is_valid;
1222 	for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
1223 		is_valid = cpu_port_is_valid(&cpu_port[cpu]);
1224 		if (is_valid && cpu_port_match(&cpu_port[cpu], mpidr)) {
1225 			cci_port_control(cpu_port[cpu].port, false);
1226 			return 0;
1227 		}
1228 	}
1229 	return -ENODEV;
1230 }
1231 EXPORT_SYMBOL_GPL(cci_disable_port_by_cpu);
1232 
1233 /**
1234  * cci_enable_port_for_self() - enable a CCI port for calling CPU
1235  *
1236  * Enabling a CCI port for the calling CPU implies enabling the CCI
1237  * port controlling that CPU's cluster. Caller must make sure that the
1238  * CPU running the code is the first active CPU in the cluster and all
1239  * other CPUs are quiescent in a low power state  or waiting for this CPU
1240  * to complete the CCI initialization.
1241  *
1242  * Because this is called when the MMU is still off and with no stack,
1243  * the code must be position independent and ideally rely on callee
1244  * clobbered registers only.  To achieve this we must code this function
1245  * entirely in assembler.
1246  *
1247  * On success this returns with the proper CCI port enabled.  In case of
1248  * any failure this never returns as the inability to enable the CCI is
1249  * fatal and there is no possible recovery at this stage.
1250  */
1251 asmlinkage void __naked cci_enable_port_for_self(void)
1252 {
1253 	asm volatile ("\n"
1254 "	.arch armv7-a\n"
1255 "	mrc	p15, 0, r0, c0, c0, 5	@ get MPIDR value \n"
1256 "	and	r0, r0, #"__stringify(MPIDR_HWID_BITMASK)" \n"
1257 "	adr	r1, 5f \n"
1258 "	ldr	r2, [r1] \n"
1259 "	add	r1, r1, r2		@ &cpu_port \n"
1260 "	add	ip, r1, %[sizeof_cpu_port] \n"
1261 
1262 	/* Loop over the cpu_port array looking for a matching MPIDR */
1263 "1:	ldr	r2, [r1, %[offsetof_cpu_port_mpidr_lsb]] \n"
1264 "	cmp	r2, r0 			@ compare MPIDR \n"
1265 "	bne	2f \n"
1266 
1267 	/* Found a match, now test port validity */
1268 "	ldr	r3, [r1, %[offsetof_cpu_port_port]] \n"
1269 "	tst	r3, #"__stringify(PORT_VALID)" \n"
1270 "	bne	3f \n"
1271 
1272 	/* no match, loop with the next cpu_port entry */
1273 "2:	add	r1, r1, %[sizeof_struct_cpu_port] \n"
1274 "	cmp	r1, ip			@ done? \n"
1275 "	blo	1b \n"
1276 
1277 	/* CCI port not found -- cheaply try to stall this CPU */
1278 "cci_port_not_found: \n"
1279 "	wfi \n"
1280 "	wfe \n"
1281 "	b	cci_port_not_found \n"
1282 
1283 	/* Use matched port index to look up the corresponding ports entry */
1284 "3:	bic	r3, r3, #"__stringify(PORT_VALID)" \n"
1285 "	adr	r0, 6f \n"
1286 "	ldmia	r0, {r1, r2} \n"
1287 "	sub	r1, r1, r0 		@ virt - phys \n"
1288 "	ldr	r0, [r0, r2] 		@ *(&ports) \n"
1289 "	mov	r2, %[sizeof_struct_ace_port] \n"
1290 "	mla	r0, r2, r3, r0		@ &ports[index] \n"
1291 "	sub	r0, r0, r1		@ virt_to_phys() \n"
1292 
1293 	/* Enable the CCI port */
1294 "	ldr	r0, [r0, %[offsetof_port_phys]] \n"
1295 "	mov	r3, %[cci_enable_req]\n"
1296 "	str	r3, [r0, #"__stringify(CCI_PORT_CTRL)"] \n"
1297 
1298 	/* poll the status reg for completion */
1299 "	adr	r1, 7f \n"
1300 "	ldr	r0, [r1] \n"
1301 "	ldr	r0, [r0, r1]		@ cci_ctrl_base \n"
1302 "4:	ldr	r1, [r0, #"__stringify(CCI_CTRL_STATUS)"] \n"
1303 "	tst	r1, %[cci_control_status_bits] \n"
1304 "	bne	4b \n"
1305 
1306 "	mov	r0, #0 \n"
1307 "	bx	lr \n"
1308 
1309 "	.align	2 \n"
1310 "5:	.word	cpu_port - . \n"
1311 "6:	.word	. \n"
1312 "	.word	ports - 6b \n"
1313 "7:	.word	cci_ctrl_phys - . \n"
1314 	: :
1315 	[sizeof_cpu_port] "i" (sizeof(cpu_port)),
1316 	[cci_enable_req] "i" cpu_to_le32(CCI_ENABLE_REQ),
1317 	[cci_control_status_bits] "i" cpu_to_le32(1),
1318 #ifndef __ARMEB__
1319 	[offsetof_cpu_port_mpidr_lsb] "i" (offsetof(struct cpu_port, mpidr)),
1320 #else
1321 	[offsetof_cpu_port_mpidr_lsb] "i" (offsetof(struct cpu_port, mpidr)+4),
1322 #endif
1323 	[offsetof_cpu_port_port] "i" (offsetof(struct cpu_port, port)),
1324 	[sizeof_struct_cpu_port] "i" (sizeof(struct cpu_port)),
1325 	[sizeof_struct_ace_port] "i" (sizeof(struct cci_ace_port)),
1326 	[offsetof_port_phys] "i" (offsetof(struct cci_ace_port, phys)) );
1327 
1328 	unreachable();
1329 }
1330 
1331 /**
1332  * __cci_control_port_by_device() - function to control a CCI port by device
1333  *				    reference
1334  *
1335  * @dn: device node pointer of the device whose CCI port should be
1336  *      controlled
1337  * @enable: if true enables the port, if false disables it
1338  *
1339  * Return:
1340  *	0 on success
1341  *	-ENODEV on port look-up failure
1342  */
1343 int notrace __cci_control_port_by_device(struct device_node *dn, bool enable)
1344 {
1345 	int port;
1346 
1347 	if (!dn)
1348 		return -ENODEV;
1349 
1350 	port = __cci_ace_get_port(dn, ACE_LITE_PORT);
1351 	if (WARN_ONCE(port < 0, "node %s ACE lite port look-up failure\n",
1352 				dn->full_name))
1353 		return -ENODEV;
1354 	cci_port_control(port, enable);
1355 	return 0;
1356 }
1357 EXPORT_SYMBOL_GPL(__cci_control_port_by_device);
1358 
1359 /**
1360  * __cci_control_port_by_index() - function to control a CCI port by port index
1361  *
1362  * @port: port index previously retrieved with cci_ace_get_port()
1363  * @enable: if true enables the port, if false disables it
1364  *
1365  * Return:
1366  *	0 on success
1367  *	-ENODEV on port index out of range
1368  *	-EPERM if operation carried out on an ACE PORT
1369  */
1370 int notrace __cci_control_port_by_index(u32 port, bool enable)
1371 {
1372 	if (port >= nb_cci_ports || ports[port].type == ACE_INVALID_PORT)
1373 		return -ENODEV;
1374 	/*
1375 	 * CCI control for ports connected to CPUS is extremely fragile
1376 	 * and must be made to go through a specific and controlled
1377 	 * interface (ie cci_disable_port_by_cpu(); control by general purpose
1378 	 * indexing is therefore disabled for ACE ports.
1379 	 */
1380 	if (ports[port].type == ACE_PORT)
1381 		return -EPERM;
1382 
1383 	cci_port_control(port, enable);
1384 	return 0;
1385 }
1386 EXPORT_SYMBOL_GPL(__cci_control_port_by_index);
1387 
1388 static const struct of_device_id arm_cci_ctrl_if_matches[] = {
1389 	{.compatible = "arm,cci-400-ctrl-if", },
1390 	{},
1391 };
1392 
1393 static int cci_probe_ports(struct device_node *np)
1394 {
1395 	struct cci_nb_ports const *cci_config;
1396 	int ret, i, nb_ace = 0, nb_ace_lite = 0;
1397 	struct device_node *cp;
1398 	struct resource res;
1399 	const char *match_str;
1400 	bool is_ace;
1401 
1402 
1403 	cci_config = of_match_node(arm_cci_matches, np)->data;
1404 	if (!cci_config)
1405 		return -ENODEV;
1406 
1407 	nb_cci_ports = cci_config->nb_ace + cci_config->nb_ace_lite;
1408 
1409 	ports = kcalloc(nb_cci_ports, sizeof(*ports), GFP_KERNEL);
1410 	if (!ports)
1411 		return -ENOMEM;
1412 
1413 	for_each_child_of_node(np, cp) {
1414 		if (!of_match_node(arm_cci_ctrl_if_matches, cp))
1415 			continue;
1416 
1417 		i = nb_ace + nb_ace_lite;
1418 
1419 		if (i >= nb_cci_ports)
1420 			break;
1421 
1422 		if (of_property_read_string(cp, "interface-type",
1423 					&match_str)) {
1424 			WARN(1, "node %s missing interface-type property\n",
1425 				  cp->full_name);
1426 			continue;
1427 		}
1428 		is_ace = strcmp(match_str, "ace") == 0;
1429 		if (!is_ace && strcmp(match_str, "ace-lite")) {
1430 			WARN(1, "node %s containing invalid interface-type property, skipping it\n",
1431 					cp->full_name);
1432 			continue;
1433 		}
1434 
1435 		ret = of_address_to_resource(cp, 0, &res);
1436 		if (!ret) {
1437 			ports[i].base = ioremap(res.start, resource_size(&res));
1438 			ports[i].phys = res.start;
1439 		}
1440 		if (ret || !ports[i].base) {
1441 			WARN(1, "unable to ioremap CCI port %d\n", i);
1442 			continue;
1443 		}
1444 
1445 		if (is_ace) {
1446 			if (WARN_ON(nb_ace >= cci_config->nb_ace))
1447 				continue;
1448 			ports[i].type = ACE_PORT;
1449 			++nb_ace;
1450 		} else {
1451 			if (WARN_ON(nb_ace_lite >= cci_config->nb_ace_lite))
1452 				continue;
1453 			ports[i].type = ACE_LITE_PORT;
1454 			++nb_ace_lite;
1455 		}
1456 		ports[i].dn = cp;
1457 	}
1458 
1459 	 /* initialize a stashed array of ACE ports to speed-up look-up */
1460 	cci_ace_init_ports();
1461 
1462 	/*
1463 	 * Multi-cluster systems may need this data when non-coherent, during
1464 	 * cluster power-up/power-down. Make sure it reaches main memory.
1465 	 */
1466 	sync_cache_w(&cci_ctrl_base);
1467 	sync_cache_w(&cci_ctrl_phys);
1468 	sync_cache_w(&ports);
1469 	sync_cache_w(&cpu_port);
1470 	__sync_cache_range_w(ports, sizeof(*ports) * nb_cci_ports);
1471 	pr_info("ARM CCI driver probed\n");
1472 
1473 	return 0;
1474 }
1475 #else /* !CONFIG_ARM_CCI400_PORT_CTRL */
1476 static inline int cci_probe_ports(struct device_node *np)
1477 {
1478 	return 0;
1479 }
1480 #endif /* CONFIG_ARM_CCI400_PORT_CTRL */
1481 
1482 static int cci_probe(void)
1483 {
1484 	int ret;
1485 	struct device_node *np;
1486 	struct resource res;
1487 
1488 	np = of_find_matching_node(NULL, arm_cci_matches);
1489 	if(!np || !of_device_is_available(np))
1490 		return -ENODEV;
1491 
1492 	ret = of_address_to_resource(np, 0, &res);
1493 	if (!ret) {
1494 		cci_ctrl_base = ioremap(res.start, resource_size(&res));
1495 		cci_ctrl_phys =	res.start;
1496 	}
1497 	if (ret || !cci_ctrl_base) {
1498 		WARN(1, "unable to ioremap CCI ctrl\n");
1499 		return -ENXIO;
1500 	}
1501 
1502 	return cci_probe_ports(np);
1503 }
1504 
1505 static int cci_init_status = -EAGAIN;
1506 static DEFINE_MUTEX(cci_probing);
1507 
1508 static int cci_init(void)
1509 {
1510 	if (cci_init_status != -EAGAIN)
1511 		return cci_init_status;
1512 
1513 	mutex_lock(&cci_probing);
1514 	if (cci_init_status == -EAGAIN)
1515 		cci_init_status = cci_probe();
1516 	mutex_unlock(&cci_probing);
1517 	return cci_init_status;
1518 }
1519 
1520 /*
1521  * To sort out early init calls ordering a helper function is provided to
1522  * check if the CCI driver has beed initialized. Function check if the driver
1523  * has been initialized, if not it calls the init function that probes
1524  * the driver and updates the return value.
1525  */
1526 bool cci_probed(void)
1527 {
1528 	return cci_init() == 0;
1529 }
1530 EXPORT_SYMBOL_GPL(cci_probed);
1531 
1532 early_initcall(cci_init);
1533 core_initcall(cci_platform_init);
1534 MODULE_LICENSE("GPL");
1535 MODULE_DESCRIPTION("ARM CCI support");
1536