xref: /openbmc/linux/drivers/hwtracing/ptt/hisi_ptt.c (revision 7effbd18)
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 	hisi_ptt->trace_ctrl.started = false;
187 }
188 
189 static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
190 {
191 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
192 	u32 val;
193 	int i;
194 
195 	/* Check device idle before start trace */
196 	if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
197 		pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
198 		return -EBUSY;
199 	}
200 
201 	ctrl->started = true;
202 
203 	/* Reset the DMA before start tracing */
204 	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
205 	val |= HISI_PTT_TRACE_CTRL_RST;
206 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
207 
208 	hisi_ptt_wait_dma_reset_done(hisi_ptt);
209 
210 	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
211 	val &= ~HISI_PTT_TRACE_CTRL_RST;
212 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
213 
214 	/* Reset the index of current buffer */
215 	hisi_ptt->trace_ctrl.buf_index = 0;
216 
217 	/* Zero the trace buffers */
218 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
219 		memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
220 
221 	/* Clear the interrupt status */
222 	writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
223 	writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
224 
225 	/* Set the trace control register */
226 	val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
227 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
228 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
229 	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
230 	if (!hisi_ptt->trace_ctrl.is_port)
231 		val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
232 
233 	/* Start the Trace */
234 	val |= HISI_PTT_TRACE_CTRL_EN;
235 	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
236 
237 	return 0;
238 }
239 
240 static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
241 {
242 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
243 	struct perf_output_handle *handle = &ctrl->handle;
244 	struct perf_event *event = handle->event;
245 	struct hisi_ptt_pmu_buf *buf;
246 	size_t size;
247 	void *addr;
248 
249 	buf = perf_get_aux(handle);
250 	if (!buf || !handle->size)
251 		return -EINVAL;
252 
253 	addr = ctrl->trace_buf[ctrl->buf_index].addr;
254 
255 	/*
256 	 * If we're going to stop, read the size of already traced data from
257 	 * HISI_PTT_TRACE_WR_STS. Otherwise we're coming from the interrupt,
258 	 * the data size is always HISI_PTT_TRACE_BUF_SIZE.
259 	 */
260 	if (stop) {
261 		u32 reg;
262 
263 		reg = readl(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS);
264 		size = FIELD_GET(HISI_PTT_TRACE_WR_STS_WRITE, reg);
265 	} else {
266 		size = HISI_PTT_TRACE_BUF_SIZE;
267 	}
268 
269 	memcpy(buf->base + buf->pos, addr, size);
270 	buf->pos += size;
271 
272 	/*
273 	 * Just commit the traced data if we're going to stop. Otherwise if the
274 	 * resident AUX buffer cannot contain the data of next trace buffer,
275 	 * apply a new one.
276 	 */
277 	if (stop) {
278 		perf_aux_output_end(handle, buf->pos);
279 	} else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
280 		perf_aux_output_end(handle, buf->pos);
281 
282 		buf = perf_aux_output_begin(handle, event);
283 		if (!buf)
284 			return -EINVAL;
285 
286 		buf->pos = handle->head % buf->length;
287 		if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
288 			perf_aux_output_end(handle, 0);
289 			return -EINVAL;
290 		}
291 	}
292 
293 	return 0;
294 }
295 
296 static irqreturn_t hisi_ptt_isr(int irq, void *context)
297 {
298 	struct hisi_ptt *hisi_ptt = context;
299 	u32 status, buf_idx;
300 
301 	status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
302 	if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
303 		return IRQ_NONE;
304 
305 	buf_idx = ffs(status) - 1;
306 
307 	/* Clear the interrupt status of buffer @buf_idx */
308 	writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
309 
310 	/*
311 	 * Update the AUX buffer and cache the current buffer index,
312 	 * as we need to know this and save the data when the trace
313 	 * is ended out of the interrupt handler. End the trace
314 	 * if the updating fails.
315 	 */
316 	if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
317 		hisi_ptt_trace_end(hisi_ptt);
318 	else
319 		hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
320 
321 	return IRQ_HANDLED;
322 }
323 
324 static void hisi_ptt_irq_free_vectors(void *pdev)
325 {
326 	pci_free_irq_vectors(pdev);
327 }
328 
329 static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
330 {
331 	struct pci_dev *pdev = hisi_ptt->pdev;
332 	int ret;
333 
334 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
335 	if (ret < 0) {
336 		pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
337 		return ret;
338 	}
339 
340 	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
341 	if (ret < 0)
342 		return ret;
343 
344 	ret = devm_request_threaded_irq(&pdev->dev,
345 					pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
346 					NULL, hisi_ptt_isr, 0,
347 					DRV_NAME, hisi_ptt);
348 	if (ret) {
349 		pci_err(pdev, "failed to request irq %d, ret = %d\n",
350 			pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
351 		return ret;
352 	}
353 
354 	return 0;
355 }
356 
357 static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
358 {
359 	struct pci_dev *root_port = pcie_find_root_port(pdev);
360 	struct hisi_ptt_filter_desc *filter;
361 	struct hisi_ptt *hisi_ptt = data;
362 	u32 port_devid;
363 
364 	if (!root_port)
365 		return 0;
366 
367 	port_devid = PCI_DEVID(root_port->bus->number, root_port->devfn);
368 	if (port_devid < hisi_ptt->lower_bdf ||
369 	    port_devid > hisi_ptt->upper_bdf)
370 		return 0;
371 
372 	/*
373 	 * We won't fail the probe if filter allocation failed here. The filters
374 	 * should be partial initialized and users would know which filter fails
375 	 * through the log. Other functions of PTT device are still available.
376 	 */
377 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
378 	if (!filter) {
379 		pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
380 		return -ENOMEM;
381 	}
382 
383 	filter->devid = PCI_DEVID(pdev->bus->number, pdev->devfn);
384 
385 	if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT) {
386 		filter->is_port = true;
387 		list_add_tail(&filter->list, &hisi_ptt->port_filters);
388 
389 		/* Update the available port mask */
390 		hisi_ptt->port_mask |= hisi_ptt_get_filter_val(filter->devid, true);
391 	} else {
392 		list_add_tail(&filter->list, &hisi_ptt->req_filters);
393 	}
394 
395 	return 0;
396 }
397 
398 static void hisi_ptt_release_filters(void *data)
399 {
400 	struct hisi_ptt_filter_desc *filter, *tmp;
401 	struct hisi_ptt *hisi_ptt = data;
402 
403 	list_for_each_entry_safe(filter, tmp, &hisi_ptt->req_filters, list) {
404 		list_del(&filter->list);
405 		kfree(filter);
406 	}
407 
408 	list_for_each_entry_safe(filter, tmp, &hisi_ptt->port_filters, list) {
409 		list_del(&filter->list);
410 		kfree(filter);
411 	}
412 }
413 
414 static int hisi_ptt_config_trace_buf(struct hisi_ptt *hisi_ptt)
415 {
416 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
417 	struct device *dev = &hisi_ptt->pdev->dev;
418 	int i;
419 
420 	ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
421 				       sizeof(*ctrl->trace_buf), GFP_KERNEL);
422 	if (!ctrl->trace_buf)
423 		return -ENOMEM;
424 
425 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
426 		ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
427 							     &ctrl->trace_buf[i].dma,
428 							     GFP_KERNEL);
429 		if (!ctrl->trace_buf[i].addr)
430 			return -ENOMEM;
431 	}
432 
433 	/* Configure the trace DMA buffer */
434 	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
435 		writel(lower_32_bits(ctrl->trace_buf[i].dma),
436 		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
437 		       i * HISI_PTT_TRACE_ADDR_STRIDE);
438 		writel(upper_32_bits(ctrl->trace_buf[i].dma),
439 		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
440 		       i * HISI_PTT_TRACE_ADDR_STRIDE);
441 	}
442 	writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
443 
444 	return 0;
445 }
446 
447 static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
448 {
449 	struct pci_dev *pdev = hisi_ptt->pdev;
450 	struct pci_bus *bus;
451 	int ret;
452 	u32 reg;
453 
454 	INIT_LIST_HEAD(&hisi_ptt->port_filters);
455 	INIT_LIST_HEAD(&hisi_ptt->req_filters);
456 
457 	ret = hisi_ptt_config_trace_buf(hisi_ptt);
458 	if (ret)
459 		return ret;
460 
461 	/*
462 	 * The device range register provides the information about the root
463 	 * ports which the RCiEP can control and trace. The RCiEP and the root
464 	 * ports which it supports are on the same PCIe core, with same domain
465 	 * number but maybe different bus number. The device range register
466 	 * will tell us which root ports we can support, Bit[31:16] indicates
467 	 * the upper BDF numbers of the root port, while Bit[15:0] indicates
468 	 * the lower.
469 	 */
470 	reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
471 	hisi_ptt->upper_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
472 	hisi_ptt->lower_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
473 
474 	bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper_bdf));
475 	if (bus)
476 		pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
477 
478 	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
479 	if (ret)
480 		return ret;
481 
482 	hisi_ptt->trace_ctrl.on_cpu = -1;
483 	return 0;
484 }
485 
486 static ssize_t cpumask_show(struct device *dev, struct device_attribute *attr,
487 			    char *buf)
488 {
489 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
490 	const cpumask_t *cpumask = cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev));
491 
492 	return cpumap_print_to_pagebuf(true, buf, cpumask);
493 }
494 static DEVICE_ATTR_RO(cpumask);
495 
496 static struct attribute *hisi_ptt_cpumask_attrs[] = {
497 	&dev_attr_cpumask.attr,
498 	NULL
499 };
500 
501 static const struct attribute_group hisi_ptt_cpumask_attr_group = {
502 	.attrs = hisi_ptt_cpumask_attrs,
503 };
504 
505 /*
506  * Bit 19 indicates the filter type, 1 for Root Port filter and 0 for Requester
507  * filter. Bit[15:0] indicates the filter value, for Root Port filter it's
508  * a bit mask of desired ports and for Requester filter it's the Requester ID
509  * of the desired PCIe function. Bit[18:16] is reserved for extension.
510  *
511  * See hisi_ptt.rst documentation for detailed information.
512  */
513 PMU_FORMAT_ATTR(filter,		"config:0-19");
514 PMU_FORMAT_ATTR(direction,	"config:20-23");
515 PMU_FORMAT_ATTR(type,		"config:24-31");
516 PMU_FORMAT_ATTR(format,		"config:32-35");
517 
518 static struct attribute *hisi_ptt_pmu_format_attrs[] = {
519 	&format_attr_filter.attr,
520 	&format_attr_direction.attr,
521 	&format_attr_type.attr,
522 	&format_attr_format.attr,
523 	NULL
524 };
525 
526 static struct attribute_group hisi_ptt_pmu_format_group = {
527 	.name = "format",
528 	.attrs = hisi_ptt_pmu_format_attrs,
529 };
530 
531 static const struct attribute_group *hisi_ptt_pmu_groups[] = {
532 	&hisi_ptt_cpumask_attr_group,
533 	&hisi_ptt_pmu_format_group,
534 	&hisi_ptt_tune_group,
535 	NULL
536 };
537 
538 static int hisi_ptt_trace_valid_direction(u32 val)
539 {
540 	/*
541 	 * The direction values have different effects according to the data
542 	 * format (specified in the parentheses). TLP set A/B means different
543 	 * set of TLP types. See hisi_ptt.rst documentation for more details.
544 	 */
545 	static const u32 hisi_ptt_trace_available_direction[] = {
546 		0,	/* inbound(4DW) or reserved(8DW) */
547 		1,	/* outbound(4DW) */
548 		2,	/* {in, out}bound(4DW) or inbound(8DW), TLP set A */
549 		3,	/* {in, out}bound(4DW) or inbound(8DW), TLP set B */
550 	};
551 	int i;
552 
553 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_direction); i++) {
554 		if (val == hisi_ptt_trace_available_direction[i])
555 			return 0;
556 	}
557 
558 	return -EINVAL;
559 }
560 
561 static int hisi_ptt_trace_valid_type(u32 val)
562 {
563 	/* Different types can be set simultaneously */
564 	static const u32 hisi_ptt_trace_available_type[] = {
565 		1,	/* posted_request */
566 		2,	/* non-posted_request */
567 		4,	/* completion */
568 	};
569 	int i;
570 
571 	if (!val)
572 		return -EINVAL;
573 
574 	/*
575 	 * Walk the available list and clear the valid bits of
576 	 * the config. If there is any resident bit after the
577 	 * walk then the config is invalid.
578 	 */
579 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_type); i++)
580 		val &= ~hisi_ptt_trace_available_type[i];
581 
582 	if (val)
583 		return -EINVAL;
584 
585 	return 0;
586 }
587 
588 static int hisi_ptt_trace_valid_format(u32 val)
589 {
590 	static const u32 hisi_ptt_trace_availble_format[] = {
591 		0,	/* 4DW */
592 		1,	/* 8DW */
593 	};
594 	int i;
595 
596 	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_availble_format); i++) {
597 		if (val == hisi_ptt_trace_availble_format[i])
598 			return 0;
599 	}
600 
601 	return -EINVAL;
602 }
603 
604 static int hisi_ptt_trace_valid_filter(struct hisi_ptt *hisi_ptt, u64 config)
605 {
606 	unsigned long val, port_mask = hisi_ptt->port_mask;
607 	struct hisi_ptt_filter_desc *filter;
608 
609 	hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
610 	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
611 
612 	/*
613 	 * Port filters are defined as bit mask. For port filters, check
614 	 * the bits in the @val are within the range of hisi_ptt->port_mask
615 	 * and whether it's empty or not, otherwise user has specified
616 	 * some unsupported root ports.
617 	 *
618 	 * For Requester ID filters, walk the available filter list to see
619 	 * whether we have one matched.
620 	 */
621 	if (!hisi_ptt->trace_ctrl.is_port) {
622 		list_for_each_entry(filter, &hisi_ptt->req_filters, list) {
623 			if (val == hisi_ptt_get_filter_val(filter->devid, filter->is_port))
624 				return 0;
625 		}
626 	} else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
627 		return 0;
628 	}
629 
630 	return -EINVAL;
631 }
632 
633 static void hisi_ptt_pmu_init_configs(struct hisi_ptt *hisi_ptt, struct perf_event *event)
634 {
635 	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
636 	u32 val;
637 
638 	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, event->attr.config);
639 	hisi_ptt->trace_ctrl.filter = val;
640 
641 	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
642 	ctrl->direction = val;
643 
644 	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
645 	ctrl->type = val;
646 
647 	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
648 	ctrl->format = val;
649 }
650 
651 static int hisi_ptt_pmu_event_init(struct perf_event *event)
652 {
653 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
654 	int ret;
655 	u32 val;
656 
657 	if (event->cpu < 0) {
658 		dev_dbg(event->pmu->dev, "Per-task mode not supported\n");
659 		return -EOPNOTSUPP;
660 	}
661 
662 	if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
663 		return -ENOENT;
664 
665 	ret = hisi_ptt_trace_valid_filter(hisi_ptt, event->attr.config);
666 	if (ret < 0)
667 		return ret;
668 
669 	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
670 	ret = hisi_ptt_trace_valid_direction(val);
671 	if (ret < 0)
672 		return ret;
673 
674 	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
675 	ret = hisi_ptt_trace_valid_type(val);
676 	if (ret < 0)
677 		return ret;
678 
679 	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
680 	return hisi_ptt_trace_valid_format(val);
681 }
682 
683 static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
684 				    int nr_pages, bool overwrite)
685 {
686 	struct hisi_ptt_pmu_buf *buf;
687 	struct page **pagelist;
688 	int i;
689 
690 	if (overwrite) {
691 		dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
692 		return NULL;
693 	}
694 
695 	/* If the pages size less than buffers, we cannot start trace */
696 	if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
697 		return NULL;
698 
699 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
700 	if (!buf)
701 		return NULL;
702 
703 	pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
704 	if (!pagelist)
705 		goto err;
706 
707 	for (i = 0; i < nr_pages; i++)
708 		pagelist[i] = virt_to_page(pages[i]);
709 
710 	buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
711 	if (!buf->base) {
712 		kfree(pagelist);
713 		goto err;
714 	}
715 
716 	buf->nr_pages = nr_pages;
717 	buf->length = nr_pages * PAGE_SIZE;
718 	buf->pos = 0;
719 
720 	kfree(pagelist);
721 	return buf;
722 err:
723 	kfree(buf);
724 	return NULL;
725 }
726 
727 static void hisi_ptt_pmu_free_aux(void *aux)
728 {
729 	struct hisi_ptt_pmu_buf *buf = aux;
730 
731 	vunmap(buf->base);
732 	kfree(buf);
733 }
734 
735 static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
736 {
737 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
738 	struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
739 	struct hw_perf_event *hwc = &event->hw;
740 	struct device *dev = event->pmu->dev;
741 	struct hisi_ptt_pmu_buf *buf;
742 	int cpu = event->cpu;
743 	int ret;
744 
745 	hwc->state = 0;
746 
747 	/* Serialize the perf process if user specified several CPUs */
748 	spin_lock(&hisi_ptt->pmu_lock);
749 	if (hisi_ptt->trace_ctrl.started) {
750 		dev_dbg(dev, "trace has already started\n");
751 		goto stop;
752 	}
753 
754 	/*
755 	 * Handle the interrupt on the same cpu which starts the trace to avoid
756 	 * context mismatch. Otherwise we'll trigger the WARN from the perf
757 	 * core in event_function_local(). If CPU passed is offline we'll fail
758 	 * here, just log it since we can do nothing here.
759 	 */
760 	ret = irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
761 					      cpumask_of(cpu));
762 	if (ret)
763 		dev_warn(dev, "failed to set the affinity of trace interrupt\n");
764 
765 	hisi_ptt->trace_ctrl.on_cpu = cpu;
766 
767 	buf = perf_aux_output_begin(handle, event);
768 	if (!buf) {
769 		dev_dbg(dev, "aux output begin failed\n");
770 		goto stop;
771 	}
772 
773 	buf->pos = handle->head % buf->length;
774 
775 	hisi_ptt_pmu_init_configs(hisi_ptt, event);
776 
777 	ret = hisi_ptt_trace_start(hisi_ptt);
778 	if (ret) {
779 		dev_dbg(dev, "trace start failed, ret = %d\n", ret);
780 		perf_aux_output_end(handle, 0);
781 		goto stop;
782 	}
783 
784 	spin_unlock(&hisi_ptt->pmu_lock);
785 	return;
786 stop:
787 	event->hw.state |= PERF_HES_STOPPED;
788 	spin_unlock(&hisi_ptt->pmu_lock);
789 }
790 
791 static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
792 {
793 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
794 	struct hw_perf_event *hwc = &event->hw;
795 
796 	if (hwc->state & PERF_HES_STOPPED)
797 		return;
798 
799 	spin_lock(&hisi_ptt->pmu_lock);
800 	if (hisi_ptt->trace_ctrl.started) {
801 		hisi_ptt_trace_end(hisi_ptt);
802 
803 		if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt))
804 			dev_warn(event->pmu->dev, "Device is still busy\n");
805 
806 		hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
807 	}
808 	spin_unlock(&hisi_ptt->pmu_lock);
809 
810 	hwc->state |= PERF_HES_STOPPED;
811 	perf_event_update_userpage(event);
812 	hwc->state |= PERF_HES_UPTODATE;
813 }
814 
815 static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
816 {
817 	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
818 	struct hw_perf_event *hwc = &event->hw;
819 	int cpu = event->cpu;
820 
821 	/* Only allow the cpus on the device's node to add the event */
822 	if (!cpumask_test_cpu(cpu, cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev))))
823 		return 0;
824 
825 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
826 
827 	if (flags & PERF_EF_START) {
828 		hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
829 		if (hwc->state & PERF_HES_STOPPED)
830 			return -EINVAL;
831 	}
832 
833 	return 0;
834 }
835 
836 static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
837 {
838 	hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
839 }
840 
841 static void hisi_ptt_remove_cpuhp_instance(void *hotplug_node)
842 {
843 	cpuhp_state_remove_instance_nocalls(hisi_ptt_pmu_online, hotplug_node);
844 }
845 
846 static void hisi_ptt_unregister_pmu(void *pmu)
847 {
848 	perf_pmu_unregister(pmu);
849 }
850 
851 static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
852 {
853 	u16 core_id, sicl_id;
854 	char *pmu_name;
855 	u32 reg;
856 	int ret;
857 
858 	ret = cpuhp_state_add_instance_nocalls(hisi_ptt_pmu_online,
859 					       &hisi_ptt->hotplug_node);
860 	if (ret)
861 		return ret;
862 
863 	ret = devm_add_action_or_reset(&hisi_ptt->pdev->dev,
864 				       hisi_ptt_remove_cpuhp_instance,
865 				       &hisi_ptt->hotplug_node);
866 	if (ret)
867 		return ret;
868 
869 	mutex_init(&hisi_ptt->tune_lock);
870 	spin_lock_init(&hisi_ptt->pmu_lock);
871 
872 	hisi_ptt->hisi_ptt_pmu = (struct pmu) {
873 		.module		= THIS_MODULE,
874 		.capabilities	= PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
875 		.task_ctx_nr	= perf_sw_context,
876 		.attr_groups	= hisi_ptt_pmu_groups,
877 		.event_init	= hisi_ptt_pmu_event_init,
878 		.setup_aux	= hisi_ptt_pmu_setup_aux,
879 		.free_aux	= hisi_ptt_pmu_free_aux,
880 		.start		= hisi_ptt_pmu_start,
881 		.stop		= hisi_ptt_pmu_stop,
882 		.add		= hisi_ptt_pmu_add,
883 		.del		= hisi_ptt_pmu_del,
884 	};
885 
886 	reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
887 	core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
888 	sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
889 
890 	pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
891 				  sicl_id, core_id);
892 	if (!pmu_name)
893 		return -ENOMEM;
894 
895 	ret = perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
896 	if (ret)
897 		return ret;
898 
899 	return devm_add_action_or_reset(&hisi_ptt->pdev->dev,
900 					hisi_ptt_unregister_pmu,
901 					&hisi_ptt->hisi_ptt_pmu);
902 }
903 
904 /*
905  * The DMA of PTT trace can only use direct mappings due to some
906  * hardware restriction. Check whether there is no IOMMU or the
907  * policy of the IOMMU domain is passthrough, otherwise the trace
908  * cannot work.
909  *
910  * The PTT device is supposed to behind an ARM SMMUv3, which
911  * should have passthrough the device by a quirk.
912  */
913 static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
914 {
915 	struct iommu_domain *iommu_domain;
916 
917 	iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
918 	if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
919 		return 0;
920 
921 	return -EOPNOTSUPP;
922 }
923 
924 static int hisi_ptt_probe(struct pci_dev *pdev,
925 			  const struct pci_device_id *id)
926 {
927 	struct hisi_ptt *hisi_ptt;
928 	int ret;
929 
930 	ret = hisi_ptt_check_iommu_mapping(pdev);
931 	if (ret) {
932 		pci_err(pdev, "requires direct DMA mappings\n");
933 		return ret;
934 	}
935 
936 	hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
937 	if (!hisi_ptt)
938 		return -ENOMEM;
939 
940 	hisi_ptt->pdev = pdev;
941 	pci_set_drvdata(pdev, hisi_ptt);
942 
943 	ret = pcim_enable_device(pdev);
944 	if (ret) {
945 		pci_err(pdev, "failed to enable device, ret = %d\n", ret);
946 		return ret;
947 	}
948 
949 	ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
950 	if (ret) {
951 		pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
952 		return ret;
953 	}
954 
955 	hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
956 
957 	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
958 	if (ret) {
959 		pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
960 		return ret;
961 	}
962 
963 	pci_set_master(pdev);
964 
965 	ret = hisi_ptt_register_irq(hisi_ptt);
966 	if (ret)
967 		return ret;
968 
969 	ret = hisi_ptt_init_ctrls(hisi_ptt);
970 	if (ret) {
971 		pci_err(pdev, "failed to init controls, ret = %d\n", ret);
972 		return ret;
973 	}
974 
975 	ret = hisi_ptt_register_pmu(hisi_ptt);
976 	if (ret) {
977 		pci_err(pdev, "failed to register PMU device, ret = %d", ret);
978 		return ret;
979 	}
980 
981 	return 0;
982 }
983 
984 static const struct pci_device_id hisi_ptt_id_tbl[] = {
985 	{ PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
986 	{ }
987 };
988 MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
989 
990 static struct pci_driver hisi_ptt_driver = {
991 	.name = DRV_NAME,
992 	.id_table = hisi_ptt_id_tbl,
993 	.probe = hisi_ptt_probe,
994 };
995 
996 static int hisi_ptt_cpu_teardown(unsigned int cpu, struct hlist_node *node)
997 {
998 	struct hisi_ptt *hisi_ptt;
999 	struct device *dev;
1000 	int target, src;
1001 
1002 	hisi_ptt = hlist_entry_safe(node, struct hisi_ptt, hotplug_node);
1003 	src = hisi_ptt->trace_ctrl.on_cpu;
1004 	dev = hisi_ptt->hisi_ptt_pmu.dev;
1005 
1006 	if (!hisi_ptt->trace_ctrl.started || src != cpu)
1007 		return 0;
1008 
1009 	target = cpumask_any_but(cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev)), cpu);
1010 	if (target >= nr_cpu_ids) {
1011 		dev_err(dev, "no available cpu for perf context migration\n");
1012 		return 0;
1013 	}
1014 
1015 	perf_pmu_migrate_context(&hisi_ptt->hisi_ptt_pmu, src, target);
1016 
1017 	/*
1018 	 * Also make sure the interrupt bind to the migrated CPU as well. Warn
1019 	 * the user on failure here.
1020 	 */
1021 	if (irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
1022 					    cpumask_of(target)))
1023 		dev_warn(dev, "failed to set the affinity of trace interrupt\n");
1024 
1025 	hisi_ptt->trace_ctrl.on_cpu = target;
1026 	return 0;
1027 }
1028 
1029 static int __init hisi_ptt_init(void)
1030 {
1031 	int ret;
1032 
1033 	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, DRV_NAME, NULL,
1034 				      hisi_ptt_cpu_teardown);
1035 	if (ret < 0)
1036 		return ret;
1037 	hisi_ptt_pmu_online = ret;
1038 
1039 	ret = pci_register_driver(&hisi_ptt_driver);
1040 	if (ret)
1041 		cpuhp_remove_multi_state(hisi_ptt_pmu_online);
1042 
1043 	return ret;
1044 }
1045 module_init(hisi_ptt_init);
1046 
1047 static void __exit hisi_ptt_exit(void)
1048 {
1049 	pci_unregister_driver(&hisi_ptt_driver);
1050 	cpuhp_remove_multi_state(hisi_ptt_pmu_online);
1051 }
1052 module_exit(hisi_ptt_exit);
1053 
1054 MODULE_LICENSE("GPL");
1055 MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>");
1056 MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
1057