xref: /linux/drivers/hwtracing/ptt/hisi_ptt.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for HiSilicon PCIe tune and trace device
4  *
5  * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
6  * Author: Yicong Yang <yangyicong@hisilicon.com>
7  */
8 
9 #include <linux/bitfield.h>
10 #include <linux/bitops.h>
11 #include <linux/cpuhotplug.h>
12 #include <linux/delay.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/iommu.h>
17 #include <linux/iopoll.h>
18 #include <linux/module.h>
19 #include <linux/sysfs.h>
20 #include <linux/vmalloc.h>
21 
22 #include "hisi_ptt.h"
23 
24 /* Dynamic CPU hotplug state used by PTT */
25 static enum cpuhp_state hisi_ptt_pmu_online;
26 
27 static bool hisi_ptt_wait_tuning_finish(struct hisi_ptt *hisi_ptt)
28 {
29 	u32 val;
30 
31 	return !readl_poll_timeout(hisi_ptt->iobase + HISI_PTT_TUNING_INT_STAT,
32 				   val, !(val & HISI_PTT_TUNING_INT_STAT_MASK),
33 				   HISI_PTT_WAIT_POLL_INTERVAL_US,
34 				   HISI_PTT_WAIT_TUNE_TIMEOUT_US);
35 }
36 
37 static ssize_t hisi_ptt_tune_attr_show(struct device *dev,
38 				       struct device_attribute *attr,
39 				       char *buf)
40 {
41 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
42 	struct dev_ext_attribute *ext_attr;
43 	struct hisi_ptt_tune_desc *desc;
44 	u32 reg;
45 	u16 val;
46 
47 	ext_attr = container_of(attr, struct dev_ext_attribute, attr);
48 	desc = ext_attr->var;
49 
50 	mutex_lock(&hisi_ptt->tune_lock);
51 
52 	reg = readl(hisi_ptt->iobase + HISI_PTT_TUNING_CTRL);
53 	reg &= ~(HISI_PTT_TUNING_CTRL_CODE | HISI_PTT_TUNING_CTRL_SUB);
54 	reg |= FIELD_PREP(HISI_PTT_TUNING_CTRL_CODE | HISI_PTT_TUNING_CTRL_SUB,
55 			  desc->event_code);
56 	writel(reg, hisi_ptt->iobase + HISI_PTT_TUNING_CTRL);
57 
58 	/* Write all 1 to indicates it's the read process */
59 	writel(~0U, hisi_ptt->iobase + HISI_PTT_TUNING_DATA);
60 
61 	if (!hisi_ptt_wait_tuning_finish(hisi_ptt)) {
62 		mutex_unlock(&hisi_ptt->tune_lock);
63 		return -ETIMEDOUT;
64 	}
65 
66 	reg = readl(hisi_ptt->iobase + HISI_PTT_TUNING_DATA);
67 	reg &= HISI_PTT_TUNING_DATA_VAL_MASK;
68 	val = FIELD_GET(HISI_PTT_TUNING_DATA_VAL_MASK, reg);
69 
70 	mutex_unlock(&hisi_ptt->tune_lock);
71 	return sysfs_emit(buf, "%u\n", val);
72 }
73 
74 static ssize_t hisi_ptt_tune_attr_store(struct device *dev,
75 					struct device_attribute *attr,
76 					const char *buf, size_t count)
77 {
78 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
79 	struct dev_ext_attribute *ext_attr;
80 	struct hisi_ptt_tune_desc *desc;
81 	u32 reg;
82 	u16 val;
83 
84 	ext_attr = container_of(attr, struct dev_ext_attribute, attr);
85 	desc = ext_attr->var;
86 
87 	if (kstrtou16(buf, 10, &val))
88 		return -EINVAL;
89 
90 	mutex_lock(&hisi_ptt->tune_lock);
91 
92 	reg = readl(hisi_ptt->iobase + HISI_PTT_TUNING_CTRL);
93 	reg &= ~(HISI_PTT_TUNING_CTRL_CODE | HISI_PTT_TUNING_CTRL_SUB);
94 	reg |= FIELD_PREP(HISI_PTT_TUNING_CTRL_CODE | HISI_PTT_TUNING_CTRL_SUB,
95 			  desc->event_code);
96 	writel(reg, hisi_ptt->iobase + HISI_PTT_TUNING_CTRL);
97 	writel(FIELD_PREP(HISI_PTT_TUNING_DATA_VAL_MASK, val),
98 	       hisi_ptt->iobase + HISI_PTT_TUNING_DATA);
99 
100 	if (!hisi_ptt_wait_tuning_finish(hisi_ptt)) {
101 		mutex_unlock(&hisi_ptt->tune_lock);
102 		return -ETIMEDOUT;
103 	}
104 
105 	mutex_unlock(&hisi_ptt->tune_lock);
106 	return count;
107 }
108 
109 #define HISI_PTT_TUNE_ATTR(_name, _val, _show, _store)			\
110 	static struct hisi_ptt_tune_desc _name##_desc = {		\
111 		.name = #_name,						\
112 		.event_code = (_val),					\
113 	};								\
114 	static struct dev_ext_attribute hisi_ptt_##_name##_attr = {	\
115 		.attr	= __ATTR(_name, 0600, _show, _store),		\
116 		.var	= &_name##_desc,				\
117 	}
118 
119 #define HISI_PTT_TUNE_ATTR_COMMON(_name, _val)		\
120 	HISI_PTT_TUNE_ATTR(_name, _val,			\
121 			   hisi_ptt_tune_attr_show,	\
122 			   hisi_ptt_tune_attr_store)
123 
124 /*
125  * The value of the tuning event are composed of two parts: main event code
126  * in BIT[0,15] and subevent code in BIT[16,23]. For example, qox_tx_cpl is
127  * a subevent of 'Tx path QoS control' which for tuning the weight of Tx
128  * completion TLPs. See hisi_ptt.rst documentation for more information.
129  */
130 #define HISI_PTT_TUNE_QOS_TX_CPL		(0x4 | (3 << 16))
131 #define HISI_PTT_TUNE_QOS_TX_NP			(0x4 | (4 << 16))
132 #define HISI_PTT_TUNE_QOS_TX_P			(0x4 | (5 << 16))
133 #define HISI_PTT_TUNE_RX_ALLOC_BUF_LEVEL	(0x5 | (6 << 16))
134 #define HISI_PTT_TUNE_TX_ALLOC_BUF_LEVEL	(0x5 | (7 << 16))
135 
136 HISI_PTT_TUNE_ATTR_COMMON(qos_tx_cpl, HISI_PTT_TUNE_QOS_TX_CPL);
137 HISI_PTT_TUNE_ATTR_COMMON(qos_tx_np, HISI_PTT_TUNE_QOS_TX_NP);
138 HISI_PTT_TUNE_ATTR_COMMON(qos_tx_p, HISI_PTT_TUNE_QOS_TX_P);
139 HISI_PTT_TUNE_ATTR_COMMON(rx_alloc_buf_level, HISI_PTT_TUNE_RX_ALLOC_BUF_LEVEL);
140 HISI_PTT_TUNE_ATTR_COMMON(tx_alloc_buf_level, HISI_PTT_TUNE_TX_ALLOC_BUF_LEVEL);
141 
142 static struct attribute *hisi_ptt_tune_attrs[] = {
143 	&hisi_ptt_qos_tx_cpl_attr.attr.attr,
144 	&hisi_ptt_qos_tx_np_attr.attr.attr,
145 	&hisi_ptt_qos_tx_p_attr.attr.attr,
146 	&hisi_ptt_rx_alloc_buf_level_attr.attr.attr,
147 	&hisi_ptt_tx_alloc_buf_level_attr.attr.attr,
148 	NULL,
149 };
150 
151 static struct attribute_group hisi_ptt_tune_group = {
152 	.name	= "tune",
153 	.attrs	= hisi_ptt_tune_attrs,
154 };
155 
156 static u16 hisi_ptt_get_filter_val(u16 devid, bool is_port)
157 {
158 	if (is_port)
159 		return BIT(HISI_PCIE_CORE_PORT_ID(devid & 0xff));
160 
161 	return devid;
162 }
163 
164 static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
165 {
166 	u32 val;
167 
168 	return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
169 					  val, val & HISI_PTT_TRACE_IDLE,
170 					  HISI_PTT_WAIT_POLL_INTERVAL_US,
171 					  HISI_PTT_WAIT_TRACE_TIMEOUT_US);
172 }
173 
174 static void hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
175 {
176 	u32 val;
177 
178 	readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
179 				  val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
180 				  HISI_PTT_RESET_TIMEOUT_US);
181 }
182 
183 static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
184 {
185 	writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
186 
187 	/* Mask the interrupt on the end */
188 	writel(HISI_PTT_TRACE_INT_MASK_ALL, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
189 
190 	hisi_ptt->trace_ctrl.started = false;
191 }
192 
193 static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
194 {
195 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
196 	u32 val;
197 	int i;
198 
199 	/* Check device idle before start trace */
200 	if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
201 		pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
202 		return -EBUSY;
203 	}
204 
205 	ctrl->started = true;
206 
207 	/* Reset the DMA before start tracing */
208 	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
209 	val |= HISI_PTT_TRACE_CTRL_RST;
210 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
211 
212 	hisi_ptt_wait_dma_reset_done(hisi_ptt);
213 
214 	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
215 	val &= ~HISI_PTT_TRACE_CTRL_RST;
216 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
217 
218 	/* Reset the index of current buffer */
219 	hisi_ptt->trace_ctrl.buf_index = 0;
220 
221 	/* Zero the trace buffers */
222 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
223 		memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
224 
225 	/* Clear the interrupt status */
226 	writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
227 	writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
228 
229 	/* Set the trace control register */
230 	val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
231 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
232 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
233 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
234 	if (!hisi_ptt->trace_ctrl.is_port)
235 		val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
236 
237 	/* Start the Trace */
238 	val |= HISI_PTT_TRACE_CTRL_EN;
239 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
240 
241 	return 0;
242 }
243 
244 static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
245 {
246 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
247 	struct perf_output_handle *handle = &ctrl->handle;
248 	struct perf_event *event = handle->event;
249 	struct hisi_ptt_pmu_buf *buf;
250 	size_t size;
251 	void *addr;
252 
253 	buf = perf_get_aux(handle);
254 	if (!buf || !handle->size)
255 		return -EINVAL;
256 
257 	addr = ctrl->trace_buf[ctrl->buf_index].addr;
258 
259 	/*
260 	 * If we're going to stop, read the size of already traced data from
261 	 * HISI_PTT_TRACE_WR_STS. Otherwise we're coming from the interrupt,
262 	 * the data size is always HISI_PTT_TRACE_BUF_SIZE.
263 	 */
264 	if (stop) {
265 		u32 reg;
266 
267 		reg = readl(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS);
268 		size = FIELD_GET(HISI_PTT_TRACE_WR_STS_WRITE, reg);
269 	} else {
270 		size = HISI_PTT_TRACE_BUF_SIZE;
271 	}
272 
273 	memcpy(buf->base + buf->pos, addr, size);
274 	buf->pos += size;
275 
276 	/*
277 	 * Always commit the data to the AUX buffer in time to make sure
278 	 * userspace got enough time to consume the data.
279 	 *
280 	 * If we're not going to stop, apply a new one and check whether
281 	 * there's enough room for the next trace.
282 	 */
283 	perf_aux_output_end(handle, size);
284 	if (!stop) {
285 		buf = perf_aux_output_begin(handle, event);
286 		if (!buf)
287 			return -EINVAL;
288 
289 		buf->pos = handle->head % buf->length;
290 		if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
291 			perf_aux_output_end(handle, 0);
292 			return -EINVAL;
293 		}
294 	}
295 
296 	return 0;
297 }
298 
299 static irqreturn_t hisi_ptt_isr(int irq, void *context)
300 {
301 	struct hisi_ptt *hisi_ptt = context;
302 	u32 status, buf_idx;
303 
304 	status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
305 	if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
306 		return IRQ_NONE;
307 
308 	buf_idx = ffs(status) - 1;
309 
310 	/* Clear the interrupt status of buffer @buf_idx */
311 	writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
312 
313 	/*
314 	 * Update the AUX buffer and cache the current buffer index,
315 	 * as we need to know this and save the data when the trace
316 	 * is ended out of the interrupt handler. End the trace
317 	 * if the updating fails.
318 	 */
319 	if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
320 		hisi_ptt_trace_end(hisi_ptt);
321 	else
322 		hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
323 
324 	return IRQ_HANDLED;
325 }
326 
327 static void hisi_ptt_irq_free_vectors(void *pdev)
328 {
329 	pci_free_irq_vectors(pdev);
330 }
331 
332 static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
333 {
334 	struct pci_dev *pdev = hisi_ptt->pdev;
335 	int ret;
336 
337 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
338 	if (ret < 0) {
339 		pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
340 		return ret;
341 	}
342 
343 	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
344 	if (ret < 0)
345 		return ret;
346 
347 	hisi_ptt->trace_irq = pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ);
348 	ret = devm_request_irq(&pdev->dev, hisi_ptt->trace_irq, hisi_ptt_isr,
349 				IRQF_NOBALANCING | IRQF_NO_THREAD, DRV_NAME,
350 				hisi_ptt);
351 	if (ret) {
352 		pci_err(pdev, "failed to request irq %d, ret = %d\n",
353 			hisi_ptt->trace_irq, ret);
354 		return ret;
355 	}
356 
357 	return 0;
358 }
359 
360 static void hisi_ptt_del_free_filter(struct hisi_ptt *hisi_ptt,
361 				      struct hisi_ptt_filter_desc *filter)
362 {
363 	if (filter->is_port)
364 		hisi_ptt->port_mask &= ~hisi_ptt_get_filter_val(filter->devid, true);
365 
366 	list_del(&filter->list);
367 	kfree(filter->name);
368 	kfree(filter);
369 }
370 
371 static struct hisi_ptt_filter_desc *
372 hisi_ptt_alloc_add_filter(struct hisi_ptt *hisi_ptt, u16 devid, bool is_port)
373 {
374 	struct hisi_ptt_filter_desc *filter;
375 	u8 devfn = devid & 0xff;
376 	char *filter_name;
377 
378 	filter_name = kasprintf(GFP_KERNEL, "%04x:%02x:%02x.%d", pci_domain_nr(hisi_ptt->pdev->bus),
379 				 PCI_BUS_NUM(devid), PCI_SLOT(devfn), PCI_FUNC(devfn));
380 	if (!filter_name) {
381 		pci_err(hisi_ptt->pdev, "failed to allocate name for filter %04x:%02x:%02x.%d\n",
382 			pci_domain_nr(hisi_ptt->pdev->bus), PCI_BUS_NUM(devid),
383 			PCI_SLOT(devfn), PCI_FUNC(devfn));
384 		return NULL;
385 	}
386 
387 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
388 	if (!filter) {
389 		pci_err(hisi_ptt->pdev, "failed to add filter for %s\n",
390 			filter_name);
391 		kfree(filter_name);
392 		return NULL;
393 	}
394 
395 	filter->name = filter_name;
396 	filter->is_port = is_port;
397 	filter->devid = devid;
398 
399 	if (filter->is_port) {
400 		list_add_tail(&filter->list, &hisi_ptt->port_filters);
401 
402 		/* Update the available port mask */
403 		hisi_ptt->port_mask |= hisi_ptt_get_filter_val(filter->devid, true);
404 	} else {
405 		list_add_tail(&filter->list, &hisi_ptt->req_filters);
406 	}
407 
408 	return filter;
409 }
410 
411 static ssize_t hisi_ptt_filter_show(struct device *dev, struct device_attribute *attr,
412 				    char *buf)
413 {
414 	struct hisi_ptt_filter_desc *filter;
415 	unsigned long filter_val;
416 
417 	filter = container_of(attr, struct hisi_ptt_filter_desc, attr);
418 	filter_val = hisi_ptt_get_filter_val(filter->devid, filter->is_port) |
419 		     (filter->is_port ? HISI_PTT_PMU_FILTER_IS_PORT : 0);
420 
421 	return sysfs_emit(buf, "0x%05lx\n", filter_val);
422 }
423 
424 static int hisi_ptt_create_rp_filter_attr(struct hisi_ptt *hisi_ptt,
425 					  struct hisi_ptt_filter_desc *filter)
426 {
427 	struct kobject *kobj = &hisi_ptt->hisi_ptt_pmu.dev->kobj;
428 
429 	sysfs_attr_init(&filter->attr.attr);
430 	filter->attr.attr.name = filter->name;
431 	filter->attr.attr.mode = 0400; /* DEVICE_ATTR_ADMIN_RO */
432 	filter->attr.show = hisi_ptt_filter_show;
433 
434 	return sysfs_add_file_to_group(kobj, &filter->attr.attr,
435 				       HISI_PTT_RP_FILTERS_GRP_NAME);
436 }
437 
438 static void hisi_ptt_remove_rp_filter_attr(struct hisi_ptt *hisi_ptt,
439 					  struct hisi_ptt_filter_desc *filter)
440 {
441 	struct kobject *kobj = &hisi_ptt->hisi_ptt_pmu.dev->kobj;
442 
443 	sysfs_remove_file_from_group(kobj, &filter->attr.attr,
444 				     HISI_PTT_RP_FILTERS_GRP_NAME);
445 }
446 
447 static int hisi_ptt_create_req_filter_attr(struct hisi_ptt *hisi_ptt,
448 					   struct hisi_ptt_filter_desc *filter)
449 {
450 	struct kobject *kobj = &hisi_ptt->hisi_ptt_pmu.dev->kobj;
451 
452 	sysfs_attr_init(&filter->attr.attr);
453 	filter->attr.attr.name = filter->name;
454 	filter->attr.attr.mode = 0400; /* DEVICE_ATTR_ADMIN_RO */
455 	filter->attr.show = hisi_ptt_filter_show;
456 
457 	return sysfs_add_file_to_group(kobj, &filter->attr.attr,
458 				       HISI_PTT_REQ_FILTERS_GRP_NAME);
459 }
460 
461 static void hisi_ptt_remove_req_filter_attr(struct hisi_ptt *hisi_ptt,
462 					   struct hisi_ptt_filter_desc *filter)
463 {
464 	struct kobject *kobj = &hisi_ptt->hisi_ptt_pmu.dev->kobj;
465 
466 	sysfs_remove_file_from_group(kobj, &filter->attr.attr,
467 				     HISI_PTT_REQ_FILTERS_GRP_NAME);
468 }
469 
470 static int hisi_ptt_create_filter_attr(struct hisi_ptt *hisi_ptt,
471 				       struct hisi_ptt_filter_desc *filter)
472 {
473 	int ret;
474 
475 	if (filter->is_port)
476 		ret = hisi_ptt_create_rp_filter_attr(hisi_ptt, filter);
477 	else
478 		ret = hisi_ptt_create_req_filter_attr(hisi_ptt, filter);
479 
480 	if (ret)
481 		pci_err(hisi_ptt->pdev, "failed to create sysfs attribute for filter %s\n",
482 			filter->name);
483 
484 	return ret;
485 }
486 
487 static void hisi_ptt_remove_filter_attr(struct hisi_ptt *hisi_ptt,
488 					struct hisi_ptt_filter_desc *filter)
489 {
490 	if (filter->is_port)
491 		hisi_ptt_remove_rp_filter_attr(hisi_ptt, filter);
492 	else
493 		hisi_ptt_remove_req_filter_attr(hisi_ptt, filter);
494 }
495 
496 static void hisi_ptt_remove_all_filter_attributes(void *data)
497 {
498 	struct hisi_ptt_filter_desc *filter;
499 	struct hisi_ptt *hisi_ptt = data;
500 
501 	mutex_lock(&hisi_ptt->filter_lock);
502 
503 	list_for_each_entry(filter, &hisi_ptt->req_filters, list)
504 		hisi_ptt_remove_filter_attr(hisi_ptt, filter);
505 
506 	list_for_each_entry(filter, &hisi_ptt->port_filters, list)
507 		hisi_ptt_remove_filter_attr(hisi_ptt, filter);
508 
509 	hisi_ptt->sysfs_inited = false;
510 	mutex_unlock(&hisi_ptt->filter_lock);
511 }
512 
513 static int hisi_ptt_init_filter_attributes(struct hisi_ptt *hisi_ptt)
514 {
515 	struct hisi_ptt_filter_desc *filter;
516 	int ret;
517 
518 	mutex_lock(&hisi_ptt->filter_lock);
519 
520 	/*
521 	 * Register the reset callback in the first stage. In reset we traverse
522 	 * the filters list to remove the sysfs attributes so the callback can
523 	 * be called safely even without below filter attributes creation.
524 	 */
525 	ret = devm_add_action(&hisi_ptt->pdev->dev,
526 			      hisi_ptt_remove_all_filter_attributes,
527 			      hisi_ptt);
528 	if (ret)
529 		goto out;
530 
531 	list_for_each_entry(filter, &hisi_ptt->port_filters, list) {
532 		ret = hisi_ptt_create_filter_attr(hisi_ptt, filter);
533 		if (ret)
534 			goto out;
535 	}
536 
537 	list_for_each_entry(filter, &hisi_ptt->req_filters, list) {
538 		ret = hisi_ptt_create_filter_attr(hisi_ptt, filter);
539 		if (ret)
540 			goto out;
541 	}
542 
543 	hisi_ptt->sysfs_inited = true;
544 out:
545 	mutex_unlock(&hisi_ptt->filter_lock);
546 	return ret;
547 }
548 
549 static void hisi_ptt_update_filters(struct work_struct *work)
550 {
551 	struct delayed_work *delayed_work = to_delayed_work(work);
552 	struct hisi_ptt_filter_update_info info;
553 	struct hisi_ptt_filter_desc *filter;
554 	struct hisi_ptt *hisi_ptt;
555 
556 	hisi_ptt = container_of(delayed_work, struct hisi_ptt, work);
557 
558 	if (!mutex_trylock(&hisi_ptt->filter_lock)) {
559 		schedule_delayed_work(&hisi_ptt->work, HISI_PTT_WORK_DELAY_MS);
560 		return;
561 	}
562 
563 	while (kfifo_get(&hisi_ptt->filter_update_kfifo, &info)) {
564 		if (info.is_add) {
565 			/*
566 			 * Notify the users if failed to add this filter, others
567 			 * still work and available. See the comments in
568 			 * hisi_ptt_init_filters().
569 			 */
570 			filter = hisi_ptt_alloc_add_filter(hisi_ptt, info.devid, info.is_port);
571 			if (!filter)
572 				continue;
573 
574 			/*
575 			 * If filters' sysfs entries hasn't been initialized,
576 			 * then we're still at probe stage. Add the filters to
577 			 * the list and later hisi_ptt_init_filter_attributes()
578 			 * will create sysfs attributes for all the filters.
579 			 */
580 			if (hisi_ptt->sysfs_inited &&
581 			    hisi_ptt_create_filter_attr(hisi_ptt, filter)) {
582 				hisi_ptt_del_free_filter(hisi_ptt, filter);
583 				continue;
584 			}
585 		} else {
586 			struct hisi_ptt_filter_desc *tmp;
587 			struct list_head *target_list;
588 
589 			target_list = info.is_port ? &hisi_ptt->port_filters :
590 				      &hisi_ptt->req_filters;
591 
592 			list_for_each_entry_safe(filter, tmp, target_list, list)
593 				if (filter->devid == info.devid) {
594 					if (hisi_ptt->sysfs_inited)
595 						hisi_ptt_remove_filter_attr(hisi_ptt, filter);
596 
597 					hisi_ptt_del_free_filter(hisi_ptt, filter);
598 					break;
599 				}
600 		}
601 	}
602 
603 	mutex_unlock(&hisi_ptt->filter_lock);
604 }
605 
606 /*
607  * A PCI bus notifier is used here for dynamically updating the filter
608  * list.
609  */
610 static int hisi_ptt_notifier_call(struct notifier_block *nb, unsigned long action,
611 				  void *data)
612 {
613 	struct hisi_ptt *hisi_ptt = container_of(nb, struct hisi_ptt, hisi_ptt_nb);
614 	struct hisi_ptt_filter_update_info info;
615 	struct pci_dev *pdev, *root_port;
616 	struct device *dev = data;
617 	u32 port_devid;
618 
619 	pdev = to_pci_dev(dev);
620 	root_port = pcie_find_root_port(pdev);
621 	if (!root_port)
622 		return 0;
623 
624 	port_devid = pci_dev_id(root_port);
625 	if (port_devid < hisi_ptt->lower_bdf ||
626 	    port_devid > hisi_ptt->upper_bdf)
627 		return 0;
628 
629 	info.is_port = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT;
630 	info.devid = pci_dev_id(pdev);
631 
632 	switch (action) {
633 	case BUS_NOTIFY_ADD_DEVICE:
634 		info.is_add = true;
635 		break;
636 	case BUS_NOTIFY_DEL_DEVICE:
637 		info.is_add = false;
638 		break;
639 	default:
640 		return 0;
641 	}
642 
643 	/*
644 	 * The FIFO size is 16 which is sufficient for almost all the cases,
645 	 * since each PCIe core will have most 8 Root Ports (typically only
646 	 * 1~4 Root Ports). On failure log the failed filter and let user
647 	 * handle it.
648 	 */
649 	if (kfifo_in_spinlocked(&hisi_ptt->filter_update_kfifo, &info, 1,
650 				&hisi_ptt->filter_update_lock))
651 		schedule_delayed_work(&hisi_ptt->work, 0);
652 	else
653 		pci_warn(hisi_ptt->pdev,
654 			 "filter update fifo overflow for target %s\n",
655 			 pci_name(pdev));
656 
657 	return 0;
658 }
659 
660 static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
661 {
662 	struct pci_dev *root_port = pcie_find_root_port(pdev);
663 	struct hisi_ptt_filter_desc *filter;
664 	struct hisi_ptt *hisi_ptt = data;
665 	u32 port_devid;
666 
667 	if (!root_port)
668 		return 0;
669 
670 	port_devid = pci_dev_id(root_port);
671 	if (port_devid < hisi_ptt->lower_bdf ||
672 	    port_devid > hisi_ptt->upper_bdf)
673 		return 0;
674 
675 	/*
676 	 * We won't fail the probe if filter allocation failed here. The filters
677 	 * should be partial initialized and users would know which filter fails
678 	 * through the log. Other functions of PTT device are still available.
679 	 */
680 	filter = hisi_ptt_alloc_add_filter(hisi_ptt, pci_dev_id(pdev),
681 					    pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT);
682 	if (!filter)
683 		return -ENOMEM;
684 
685 	return 0;
686 }
687 
688 static void hisi_ptt_release_filters(void *data)
689 {
690 	struct hisi_ptt_filter_desc *filter, *tmp;
691 	struct hisi_ptt *hisi_ptt = data;
692 
693 	list_for_each_entry_safe(filter, tmp, &hisi_ptt->req_filters, list)
694 		hisi_ptt_del_free_filter(hisi_ptt, filter);
695 
696 	list_for_each_entry_safe(filter, tmp, &hisi_ptt->port_filters, list)
697 		hisi_ptt_del_free_filter(hisi_ptt, filter);
698 }
699 
700 static int hisi_ptt_config_trace_buf(struct hisi_ptt *hisi_ptt)
701 {
702 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
703 	struct device *dev = &hisi_ptt->pdev->dev;
704 	int i;
705 
706 	ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
707 				       sizeof(*ctrl->trace_buf), GFP_KERNEL);
708 	if (!ctrl->trace_buf)
709 		return -ENOMEM;
710 
711 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
712 		ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
713 							     &ctrl->trace_buf[i].dma,
714 							     GFP_KERNEL);
715 		if (!ctrl->trace_buf[i].addr)
716 			return -ENOMEM;
717 	}
718 
719 	/* Configure the trace DMA buffer */
720 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
721 		writel(lower_32_bits(ctrl->trace_buf[i].dma),
722 		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
723 		       i * HISI_PTT_TRACE_ADDR_STRIDE);
724 		writel(upper_32_bits(ctrl->trace_buf[i].dma),
725 		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
726 		       i * HISI_PTT_TRACE_ADDR_STRIDE);
727 	}
728 	writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
729 
730 	return 0;
731 }
732 
733 static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
734 {
735 	struct pci_dev *pdev = hisi_ptt->pdev;
736 	struct pci_bus *bus;
737 	int ret;
738 	u32 reg;
739 
740 	INIT_DELAYED_WORK(&hisi_ptt->work, hisi_ptt_update_filters);
741 	INIT_KFIFO(hisi_ptt->filter_update_kfifo);
742 	spin_lock_init(&hisi_ptt->filter_update_lock);
743 
744 	INIT_LIST_HEAD(&hisi_ptt->port_filters);
745 	INIT_LIST_HEAD(&hisi_ptt->req_filters);
746 	mutex_init(&hisi_ptt->filter_lock);
747 
748 	ret = hisi_ptt_config_trace_buf(hisi_ptt);
749 	if (ret)
750 		return ret;
751 
752 	/*
753 	 * The device range register provides the information about the root
754 	 * ports which the RCiEP can control and trace. The RCiEP and the root
755 	 * ports which it supports are on the same PCIe core, with same domain
756 	 * number but maybe different bus number. The device range register
757 	 * will tell us which root ports we can support, Bit[31:16] indicates
758 	 * the upper BDF numbers of the root port, while Bit[15:0] indicates
759 	 * the lower.
760 	 */
761 	reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
762 	hisi_ptt->upper_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
763 	hisi_ptt->lower_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
764 
765 	bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper_bdf));
766 	if (bus)
767 		pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
768 
769 	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
770 	if (ret)
771 		return ret;
772 
773 	hisi_ptt->trace_ctrl.on_cpu = -1;
774 	return 0;
775 }
776 
777 static ssize_t cpumask_show(struct device *dev, struct device_attribute *attr,
778 			    char *buf)
779 {
780 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
781 	const cpumask_t *cpumask = cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev));
782 
783 	return cpumap_print_to_pagebuf(true, buf, cpumask);
784 }
785 static DEVICE_ATTR_RO(cpumask);
786 
787 static struct attribute *hisi_ptt_cpumask_attrs[] = {
788 	&dev_attr_cpumask.attr,
789 	NULL
790 };
791 
792 static const struct attribute_group hisi_ptt_cpumask_attr_group = {
793 	.attrs = hisi_ptt_cpumask_attrs,
794 };
795 
796 /*
797  * Bit 19 indicates the filter type, 1 for Root Port filter and 0 for Requester
798  * filter. Bit[15:0] indicates the filter value, for Root Port filter it's
799  * a bit mask of desired ports and for Requester filter it's the Requester ID
800  * of the desired PCIe function. Bit[18:16] is reserved for extension.
801  *
802  * See hisi_ptt.rst documentation for detailed information.
803  */
804 PMU_FORMAT_ATTR(filter,		"config:0-19");
805 PMU_FORMAT_ATTR(direction,	"config:20-23");
806 PMU_FORMAT_ATTR(type,		"config:24-31");
807 PMU_FORMAT_ATTR(format,		"config:32-35");
808 
809 static struct attribute *hisi_ptt_pmu_format_attrs[] = {
810 	&format_attr_filter.attr,
811 	&format_attr_direction.attr,
812 	&format_attr_type.attr,
813 	&format_attr_format.attr,
814 	NULL
815 };
816 
817 static struct attribute_group hisi_ptt_pmu_format_group = {
818 	.name = "format",
819 	.attrs = hisi_ptt_pmu_format_attrs,
820 };
821 
822 static ssize_t hisi_ptt_filter_multiselect_show(struct device *dev,
823 						struct device_attribute *attr,
824 						char *buf)
825 {
826 	struct dev_ext_attribute *ext_attr;
827 
828 	ext_attr = container_of(attr, struct dev_ext_attribute, attr);
829 	return sysfs_emit(buf, "%s\n", (char *)ext_attr->var);
830 }
831 
832 static struct dev_ext_attribute root_port_filters_multiselect = {
833 	.attr = {
834 		.attr = { .name = "multiselect", .mode = 0400 },
835 		.show = hisi_ptt_filter_multiselect_show,
836 	},
837 	.var = "1",
838 };
839 
840 static struct attribute *hisi_ptt_pmu_root_ports_attrs[] = {
841 	&root_port_filters_multiselect.attr.attr,
842 	NULL
843 };
844 
845 static struct attribute_group hisi_ptt_pmu_root_ports_group = {
846 	.name = HISI_PTT_RP_FILTERS_GRP_NAME,
847 	.attrs = hisi_ptt_pmu_root_ports_attrs,
848 };
849 
850 static struct dev_ext_attribute requester_filters_multiselect = {
851 	.attr = {
852 		.attr = { .name = "multiselect", .mode = 0400 },
853 		.show = hisi_ptt_filter_multiselect_show,
854 	},
855 	.var = "0",
856 };
857 
858 static struct attribute *hisi_ptt_pmu_requesters_attrs[] = {
859 	&requester_filters_multiselect.attr.attr,
860 	NULL
861 };
862 
863 static struct attribute_group hisi_ptt_pmu_requesters_group = {
864 	.name = HISI_PTT_REQ_FILTERS_GRP_NAME,
865 	.attrs = hisi_ptt_pmu_requesters_attrs,
866 };
867 
868 static const struct attribute_group *hisi_ptt_pmu_groups[] = {
869 	&hisi_ptt_cpumask_attr_group,
870 	&hisi_ptt_pmu_format_group,
871 	&hisi_ptt_tune_group,
872 	&hisi_ptt_pmu_root_ports_group,
873 	&hisi_ptt_pmu_requesters_group,
874 	NULL
875 };
876 
877 static int hisi_ptt_trace_valid_direction(u32 val)
878 {
879 	/*
880 	 * The direction values have different effects according to the data
881 	 * format (specified in the parentheses). TLP set A/B means different
882 	 * set of TLP types. See hisi_ptt.rst documentation for more details.
883 	 */
884 	static const u32 hisi_ptt_trace_available_direction[] = {
885 		0,	/* inbound(4DW) or reserved(8DW) */
886 		1,	/* outbound(4DW) */
887 		2,	/* {in, out}bound(4DW) or inbound(8DW), TLP set A */
888 		3,	/* {in, out}bound(4DW) or inbound(8DW), TLP set B */
889 	};
890 	int i;
891 
892 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_direction); i++) {
893 		if (val == hisi_ptt_trace_available_direction[i])
894 			return 0;
895 	}
896 
897 	return -EINVAL;
898 }
899 
900 static int hisi_ptt_trace_valid_type(u32 val)
901 {
902 	/* Different types can be set simultaneously */
903 	static const u32 hisi_ptt_trace_available_type[] = {
904 		1,	/* posted_request */
905 		2,	/* non-posted_request */
906 		4,	/* completion */
907 	};
908 	int i;
909 
910 	if (!val)
911 		return -EINVAL;
912 
913 	/*
914 	 * Walk the available list and clear the valid bits of
915 	 * the config. If there is any resident bit after the
916 	 * walk then the config is invalid.
917 	 */
918 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_type); i++)
919 		val &= ~hisi_ptt_trace_available_type[i];
920 
921 	if (val)
922 		return -EINVAL;
923 
924 	return 0;
925 }
926 
927 static int hisi_ptt_trace_valid_format(u32 val)
928 {
929 	static const u32 hisi_ptt_trace_availble_format[] = {
930 		0,	/* 4DW */
931 		1,	/* 8DW */
932 	};
933 	int i;
934 
935 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_availble_format); i++) {
936 		if (val == hisi_ptt_trace_availble_format[i])
937 			return 0;
938 	}
939 
940 	return -EINVAL;
941 }
942 
943 static int hisi_ptt_trace_valid_filter(struct hisi_ptt *hisi_ptt, u64 config)
944 {
945 	unsigned long val, port_mask = hisi_ptt->port_mask;
946 	struct hisi_ptt_filter_desc *filter;
947 	int ret = 0;
948 
949 	hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
950 	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
951 
952 	/*
953 	 * Port filters are defined as bit mask. For port filters, check
954 	 * the bits in the @val are within the range of hisi_ptt->port_mask
955 	 * and whether it's empty or not, otherwise user has specified
956 	 * some unsupported root ports.
957 	 *
958 	 * For Requester ID filters, walk the available filter list to see
959 	 * whether we have one matched.
960 	 */
961 	mutex_lock(&hisi_ptt->filter_lock);
962 	if (!hisi_ptt->trace_ctrl.is_port) {
963 		list_for_each_entry(filter, &hisi_ptt->req_filters, list) {
964 			if (val == hisi_ptt_get_filter_val(filter->devid, filter->is_port))
965 				goto out;
966 		}
967 	} else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
968 		goto out;
969 	}
970 
971 	ret = -EINVAL;
972 out:
973 	mutex_unlock(&hisi_ptt->filter_lock);
974 	return ret;
975 }
976 
977 static void hisi_ptt_pmu_init_configs(struct hisi_ptt *hisi_ptt, struct perf_event *event)
978 {
979 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
980 	u32 val;
981 
982 	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, event->attr.config);
983 	hisi_ptt->trace_ctrl.filter = val;
984 
985 	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
986 	ctrl->direction = val;
987 
988 	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
989 	ctrl->type = val;
990 
991 	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
992 	ctrl->format = val;
993 }
994 
995 static int hisi_ptt_pmu_event_init(struct perf_event *event)
996 {
997 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
998 	int ret;
999 	u32 val;
1000 
1001 	if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
1002 		return -ENOENT;
1003 
1004 	if (event->cpu < 0) {
1005 		dev_dbg(event->pmu->dev, "Per-task mode not supported\n");
1006 		return -EOPNOTSUPP;
1007 	}
1008 
1009 	if (event->attach_state & PERF_ATTACH_TASK)
1010 		return -EOPNOTSUPP;
1011 
1012 	ret = hisi_ptt_trace_valid_filter(hisi_ptt, event->attr.config);
1013 	if (ret < 0)
1014 		return ret;
1015 
1016 	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
1017 	ret = hisi_ptt_trace_valid_direction(val);
1018 	if (ret < 0)
1019 		return ret;
1020 
1021 	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
1022 	ret = hisi_ptt_trace_valid_type(val);
1023 	if (ret < 0)
1024 		return ret;
1025 
1026 	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
1027 	return hisi_ptt_trace_valid_format(val);
1028 }
1029 
1030 static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
1031 				    int nr_pages, bool overwrite)
1032 {
1033 	struct hisi_ptt_pmu_buf *buf;
1034 	struct page **pagelist;
1035 	int i;
1036 
1037 	if (overwrite) {
1038 		dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
1039 		return NULL;
1040 	}
1041 
1042 	/* If the pages size less than buffers, we cannot start trace */
1043 	if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
1044 		return NULL;
1045 
1046 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
1047 	if (!buf)
1048 		return NULL;
1049 
1050 	pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
1051 	if (!pagelist)
1052 		goto err;
1053 
1054 	for (i = 0; i < nr_pages; i++)
1055 		pagelist[i] = virt_to_page(pages[i]);
1056 
1057 	buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
1058 	if (!buf->base) {
1059 		kfree(pagelist);
1060 		goto err;
1061 	}
1062 
1063 	buf->nr_pages = nr_pages;
1064 	buf->length = nr_pages * PAGE_SIZE;
1065 	buf->pos = 0;
1066 
1067 	kfree(pagelist);
1068 	return buf;
1069 err:
1070 	kfree(buf);
1071 	return NULL;
1072 }
1073 
1074 static void hisi_ptt_pmu_free_aux(void *aux)
1075 {
1076 	struct hisi_ptt_pmu_buf *buf = aux;
1077 
1078 	vunmap(buf->base);
1079 	kfree(buf);
1080 }
1081 
1082 static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
1083 {
1084 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
1085 	struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
1086 	struct hw_perf_event *hwc = &event->hw;
1087 	struct device *dev = event->pmu->dev;
1088 	struct hisi_ptt_pmu_buf *buf;
1089 	int cpu = event->cpu;
1090 	int ret;
1091 
1092 	hwc->state = 0;
1093 
1094 	/* Serialize the perf process if user specified several CPUs */
1095 	spin_lock(&hisi_ptt->pmu_lock);
1096 	if (hisi_ptt->trace_ctrl.started) {
1097 		dev_dbg(dev, "trace has already started\n");
1098 		goto stop;
1099 	}
1100 
1101 	/*
1102 	 * Handle the interrupt on the same cpu which starts the trace to avoid
1103 	 * context mismatch. Otherwise we'll trigger the WARN from the perf
1104 	 * core in event_function_local(). If CPU passed is offline we'll fail
1105 	 * here, just log it since we can do nothing here.
1106 	 */
1107 	ret = irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(cpu));
1108 	if (ret)
1109 		dev_warn(dev, "failed to set the affinity of trace interrupt\n");
1110 
1111 	hisi_ptt->trace_ctrl.on_cpu = cpu;
1112 
1113 	buf = perf_aux_output_begin(handle, event);
1114 	if (!buf) {
1115 		dev_dbg(dev, "aux output begin failed\n");
1116 		goto stop;
1117 	}
1118 
1119 	buf->pos = handle->head % buf->length;
1120 
1121 	hisi_ptt_pmu_init_configs(hisi_ptt, event);
1122 
1123 	ret = hisi_ptt_trace_start(hisi_ptt);
1124 	if (ret) {
1125 		dev_dbg(dev, "trace start failed, ret = %d\n", ret);
1126 		perf_aux_output_end(handle, 0);
1127 		goto stop;
1128 	}
1129 
1130 	spin_unlock(&hisi_ptt->pmu_lock);
1131 	return;
1132 stop:
1133 	event->hw.state |= PERF_HES_STOPPED;
1134 	spin_unlock(&hisi_ptt->pmu_lock);
1135 }
1136 
1137 static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
1138 {
1139 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
1140 	struct hw_perf_event *hwc = &event->hw;
1141 
1142 	if (hwc->state & PERF_HES_STOPPED)
1143 		return;
1144 
1145 	spin_lock(&hisi_ptt->pmu_lock);
1146 	if (hisi_ptt->trace_ctrl.started) {
1147 		hisi_ptt_trace_end(hisi_ptt);
1148 
1149 		if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt))
1150 			dev_warn(event->pmu->dev, "Device is still busy\n");
1151 
1152 		hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
1153 	}
1154 	spin_unlock(&hisi_ptt->pmu_lock);
1155 
1156 	hwc->state |= PERF_HES_STOPPED;
1157 	perf_event_update_userpage(event);
1158 	hwc->state |= PERF_HES_UPTODATE;
1159 }
1160 
1161 static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
1162 {
1163 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
1164 	struct hw_perf_event *hwc = &event->hw;
1165 	int cpu = event->cpu;
1166 
1167 	/* Only allow the cpus on the device's node to add the event */
1168 	if (!cpumask_test_cpu(cpu, cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev))))
1169 		return 0;
1170 
1171 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
1172 
1173 	if (flags & PERF_EF_START) {
1174 		hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
1175 		if (hwc->state & PERF_HES_STOPPED)
1176 			return -EINVAL;
1177 	}
1178 
1179 	return 0;
1180 }
1181 
1182 static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
1183 {
1184 	hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
1185 }
1186 
1187 static void hisi_ptt_pmu_read(struct perf_event *event)
1188 {
1189 }
1190 
1191 static void hisi_ptt_remove_cpuhp_instance(void *hotplug_node)
1192 {
1193 	cpuhp_state_remove_instance_nocalls(hisi_ptt_pmu_online, hotplug_node);
1194 }
1195 
1196 static void hisi_ptt_unregister_pmu(void *pmu)
1197 {
1198 	perf_pmu_unregister(pmu);
1199 }
1200 
1201 static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
1202 {
1203 	u16 core_id, sicl_id;
1204 	char *pmu_name;
1205 	u32 reg;
1206 	int ret;
1207 
1208 	ret = cpuhp_state_add_instance_nocalls(hisi_ptt_pmu_online,
1209 					       &hisi_ptt->hotplug_node);
1210 	if (ret)
1211 		return ret;
1212 
1213 	ret = devm_add_action_or_reset(&hisi_ptt->pdev->dev,
1214 				       hisi_ptt_remove_cpuhp_instance,
1215 				       &hisi_ptt->hotplug_node);
1216 	if (ret)
1217 		return ret;
1218 
1219 	mutex_init(&hisi_ptt->tune_lock);
1220 	spin_lock_init(&hisi_ptt->pmu_lock);
1221 
1222 	hisi_ptt->hisi_ptt_pmu = (struct pmu) {
1223 		.module		= THIS_MODULE,
1224 		.parent         = &hisi_ptt->pdev->dev,
1225 		.capabilities	= PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_NO_EXCLUDE,
1226 		.task_ctx_nr	= perf_sw_context,
1227 		.attr_groups	= hisi_ptt_pmu_groups,
1228 		.event_init	= hisi_ptt_pmu_event_init,
1229 		.setup_aux	= hisi_ptt_pmu_setup_aux,
1230 		.free_aux	= hisi_ptt_pmu_free_aux,
1231 		.start		= hisi_ptt_pmu_start,
1232 		.stop		= hisi_ptt_pmu_stop,
1233 		.add		= hisi_ptt_pmu_add,
1234 		.del		= hisi_ptt_pmu_del,
1235 		.read		= hisi_ptt_pmu_read,
1236 	};
1237 
1238 	reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
1239 	core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
1240 	sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
1241 
1242 	pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
1243 				  sicl_id, core_id);
1244 	if (!pmu_name)
1245 		return -ENOMEM;
1246 
1247 	ret = perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
1248 	if (ret)
1249 		return ret;
1250 
1251 	return devm_add_action_or_reset(&hisi_ptt->pdev->dev,
1252 					hisi_ptt_unregister_pmu,
1253 					&hisi_ptt->hisi_ptt_pmu);
1254 }
1255 
1256 static void hisi_ptt_unregister_filter_update_notifier(void *data)
1257 {
1258 	struct hisi_ptt *hisi_ptt = data;
1259 
1260 	bus_unregister_notifier(&pci_bus_type, &hisi_ptt->hisi_ptt_nb);
1261 
1262 	/* Cancel any work that has been queued */
1263 	cancel_delayed_work_sync(&hisi_ptt->work);
1264 }
1265 
1266 /* Register the bus notifier for dynamically updating the filter list */
1267 static int hisi_ptt_register_filter_update_notifier(struct hisi_ptt *hisi_ptt)
1268 {
1269 	int ret;
1270 
1271 	hisi_ptt->hisi_ptt_nb.notifier_call = hisi_ptt_notifier_call;
1272 	ret = bus_register_notifier(&pci_bus_type, &hisi_ptt->hisi_ptt_nb);
1273 	if (ret)
1274 		return ret;
1275 
1276 	return devm_add_action_or_reset(&hisi_ptt->pdev->dev,
1277 					hisi_ptt_unregister_filter_update_notifier,
1278 					hisi_ptt);
1279 }
1280 
1281 /*
1282  * The DMA of PTT trace can only use direct mappings due to some
1283  * hardware restriction. Check whether there is no IOMMU or the
1284  * policy of the IOMMU domain is passthrough, otherwise the trace
1285  * cannot work.
1286  *
1287  * The PTT device is supposed to behind an ARM SMMUv3, which
1288  * should have passthrough the device by a quirk.
1289  */
1290 static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
1291 {
1292 	struct iommu_domain *iommu_domain;
1293 
1294 	iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
1295 	if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
1296 		return 0;
1297 
1298 	return -EOPNOTSUPP;
1299 }
1300 
1301 static int hisi_ptt_probe(struct pci_dev *pdev,
1302 			  const struct pci_device_id *id)
1303 {
1304 	struct hisi_ptt *hisi_ptt;
1305 	int ret;
1306 
1307 	ret = hisi_ptt_check_iommu_mapping(pdev);
1308 	if (ret) {
1309 		pci_err(pdev, "requires direct DMA mappings\n");
1310 		return ret;
1311 	}
1312 
1313 	hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
1314 	if (!hisi_ptt)
1315 		return -ENOMEM;
1316 
1317 	hisi_ptt->pdev = pdev;
1318 	pci_set_drvdata(pdev, hisi_ptt);
1319 
1320 	ret = pcim_enable_device(pdev);
1321 	if (ret) {
1322 		pci_err(pdev, "failed to enable device, ret = %d\n", ret);
1323 		return ret;
1324 	}
1325 
1326 	ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
1327 	if (ret) {
1328 		pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
1329 		return ret;
1330 	}
1331 
1332 	hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
1333 
1334 	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
1335 	if (ret) {
1336 		pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
1337 		return ret;
1338 	}
1339 
1340 	pci_set_master(pdev);
1341 
1342 	ret = hisi_ptt_register_irq(hisi_ptt);
1343 	if (ret)
1344 		return ret;
1345 
1346 	ret = hisi_ptt_init_ctrls(hisi_ptt);
1347 	if (ret) {
1348 		pci_err(pdev, "failed to init controls, ret = %d\n", ret);
1349 		return ret;
1350 	}
1351 
1352 	ret = hisi_ptt_register_filter_update_notifier(hisi_ptt);
1353 	if (ret)
1354 		pci_warn(pdev, "failed to register filter update notifier, ret = %d", ret);
1355 
1356 	ret = hisi_ptt_register_pmu(hisi_ptt);
1357 	if (ret) {
1358 		pci_err(pdev, "failed to register PMU device, ret = %d", ret);
1359 		return ret;
1360 	}
1361 
1362 	ret = hisi_ptt_init_filter_attributes(hisi_ptt);
1363 	if (ret) {
1364 		pci_err(pdev, "failed to init sysfs filter attributes, ret = %d", ret);
1365 		return ret;
1366 	}
1367 
1368 	return 0;
1369 }
1370 
1371 static const struct pci_device_id hisi_ptt_id_tbl[] = {
1372 	{ PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
1373 	{ }
1374 };
1375 MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
1376 
1377 static struct pci_driver hisi_ptt_driver = {
1378 	.name = DRV_NAME,
1379 	.id_table = hisi_ptt_id_tbl,
1380 	.probe = hisi_ptt_probe,
1381 };
1382 
1383 static int hisi_ptt_cpu_teardown(unsigned int cpu, struct hlist_node *node)
1384 {
1385 	struct hisi_ptt *hisi_ptt;
1386 	struct device *dev;
1387 	int target, src;
1388 
1389 	hisi_ptt = hlist_entry_safe(node, struct hisi_ptt, hotplug_node);
1390 	src = hisi_ptt->trace_ctrl.on_cpu;
1391 	dev = hisi_ptt->hisi_ptt_pmu.dev;
1392 
1393 	if (!hisi_ptt->trace_ctrl.started || src != cpu)
1394 		return 0;
1395 
1396 	target = cpumask_any_but(cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev)), cpu);
1397 	if (target >= nr_cpu_ids) {
1398 		dev_err(dev, "no available cpu for perf context migration\n");
1399 		return 0;
1400 	}
1401 
1402 	perf_pmu_migrate_context(&hisi_ptt->hisi_ptt_pmu, src, target);
1403 
1404 	/*
1405 	 * Also make sure the interrupt bind to the migrated CPU as well. Warn
1406 	 * the user on failure here.
1407 	 */
1408 	if (irq_set_affinity(hisi_ptt->trace_irq, cpumask_of(target)))
1409 		dev_warn(dev, "failed to set the affinity of trace interrupt\n");
1410 
1411 	hisi_ptt->trace_ctrl.on_cpu = target;
1412 	return 0;
1413 }
1414 
1415 static int __init hisi_ptt_init(void)
1416 {
1417 	int ret;
1418 
1419 	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, DRV_NAME, NULL,
1420 				      hisi_ptt_cpu_teardown);
1421 	if (ret < 0)
1422 		return ret;
1423 	hisi_ptt_pmu_online = ret;
1424 
1425 	ret = pci_register_driver(&hisi_ptt_driver);
1426 	if (ret)
1427 		cpuhp_remove_multi_state(hisi_ptt_pmu_online);
1428 
1429 	return ret;
1430 }
1431 module_init(hisi_ptt_init);
1432 
1433 static void __exit hisi_ptt_exit(void)
1434 {
1435 	pci_unregister_driver(&hisi_ptt_driver);
1436 	cpuhp_remove_multi_state(hisi_ptt_pmu_online);
1437 }
1438 module_exit(hisi_ptt_exit);
1439 
1440 MODULE_LICENSE("GPL");
1441 MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>");
1442 MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
1443