1 // SPDX-License-Identifier: GPL-2.0
2 /* Marvell CN10K LLC-TAD perf driver
3  *
4  * Copyright (C) 2021 Marvell
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #define pr_fmt(fmt) "tad_pmu: " fmt
12 
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/cpuhotplug.h>
18 #include <linux/perf_event.h>
19 #include <linux/platform_device.h>
20 
21 #define TAD_PFC_OFFSET		0x0
22 #define TAD_PFC(counter)	(TAD_PFC_OFFSET | (counter << 3))
23 #define TAD_PRF_OFFSET		0x100
24 #define TAD_PRF(counter)	(TAD_PRF_OFFSET | (counter << 3))
25 #define TAD_PRF_CNTSEL_MASK	0xFF
26 #define TAD_MAX_COUNTERS	8
27 
28 #define to_tad_pmu(p) (container_of(p, struct tad_pmu, pmu))
29 
30 struct tad_region {
31 	void __iomem	*base;
32 };
33 
34 struct tad_pmu {
35 	struct pmu pmu;
36 	struct tad_region *regions;
37 	u32 region_cnt;
38 	unsigned int cpu;
39 	struct hlist_node node;
40 	struct perf_event *events[TAD_MAX_COUNTERS];
41 	DECLARE_BITMAP(counters_map, TAD_MAX_COUNTERS);
42 };
43 
44 static int tad_pmu_cpuhp_state;
45 
46 static void tad_pmu_event_counter_read(struct perf_event *event)
47 {
48 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
49 	struct hw_perf_event *hwc = &event->hw;
50 	u32 counter_idx = hwc->idx;
51 	u64 prev, new;
52 	int i;
53 
54 	do {
55 		prev = local64_read(&hwc->prev_count);
56 		for (i = 0, new = 0; i < tad_pmu->region_cnt; i++)
57 			new += readq(tad_pmu->regions[i].base +
58 				     TAD_PFC(counter_idx));
59 	} while (local64_cmpxchg(&hwc->prev_count, prev, new) != prev);
60 
61 	local64_add(new - prev, &event->count);
62 }
63 
64 static void tad_pmu_event_counter_stop(struct perf_event *event, int flags)
65 {
66 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
67 	struct hw_perf_event *hwc = &event->hw;
68 	u32 counter_idx = hwc->idx;
69 	int i;
70 
71 	/* TAD()_PFC() stop counting on the write
72 	 * which sets TAD()_PRF()[CNTSEL] == 0
73 	 */
74 	for (i = 0; i < tad_pmu->region_cnt; i++) {
75 		writeq_relaxed(0, tad_pmu->regions[i].base +
76 			       TAD_PRF(counter_idx));
77 	}
78 
79 	tad_pmu_event_counter_read(event);
80 	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
81 }
82 
83 static void tad_pmu_event_counter_start(struct perf_event *event, int flags)
84 {
85 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
86 	struct hw_perf_event *hwc = &event->hw;
87 	u32 event_idx = event->attr.config;
88 	u32 counter_idx = hwc->idx;
89 	u64 reg_val;
90 	int i;
91 
92 	hwc->state = 0;
93 
94 	/* Typically TAD_PFC() are zeroed to start counting */
95 	for (i = 0; i < tad_pmu->region_cnt; i++)
96 		writeq_relaxed(0, tad_pmu->regions[i].base +
97 			       TAD_PFC(counter_idx));
98 
99 	/* TAD()_PFC() start counting on the write
100 	 * which sets TAD()_PRF()[CNTSEL] != 0
101 	 */
102 	for (i = 0; i < tad_pmu->region_cnt; i++) {
103 		reg_val = readq_relaxed(tad_pmu->regions[i].base +
104 					TAD_PRF(counter_idx));
105 		reg_val |= (event_idx & 0xFF);
106 		writeq_relaxed(reg_val,	tad_pmu->regions[i].base +
107 			       TAD_PRF(counter_idx));
108 	}
109 }
110 
111 static void tad_pmu_event_counter_del(struct perf_event *event, int flags)
112 {
113 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
114 	struct hw_perf_event *hwc = &event->hw;
115 	int idx = hwc->idx;
116 
117 	tad_pmu_event_counter_stop(event, flags | PERF_EF_UPDATE);
118 	tad_pmu->events[idx] = NULL;
119 	clear_bit(idx, tad_pmu->counters_map);
120 }
121 
122 static int tad_pmu_event_counter_add(struct perf_event *event, int flags)
123 {
124 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
125 	struct hw_perf_event *hwc = &event->hw;
126 	int idx;
127 
128 	/* Get a free counter for this event */
129 	idx = find_first_zero_bit(tad_pmu->counters_map, TAD_MAX_COUNTERS);
130 	if (idx == TAD_MAX_COUNTERS)
131 		return -EAGAIN;
132 
133 	set_bit(idx, tad_pmu->counters_map);
134 
135 	hwc->idx = idx;
136 	hwc->state = PERF_HES_STOPPED;
137 	tad_pmu->events[idx] = event;
138 
139 	if (flags & PERF_EF_START)
140 		tad_pmu_event_counter_start(event, flags);
141 
142 	return 0;
143 }
144 
145 static int tad_pmu_event_init(struct perf_event *event)
146 {
147 	struct tad_pmu *tad_pmu = to_tad_pmu(event->pmu);
148 
149 	if (!event->attr.disabled)
150 		return -EINVAL;
151 
152 	if (event->attr.type != event->pmu->type)
153 		return -ENOENT;
154 
155 	if (event->state != PERF_EVENT_STATE_OFF)
156 		return -EINVAL;
157 
158 	event->cpu = tad_pmu->cpu;
159 	event->hw.idx = -1;
160 	event->hw.config_base = event->attr.config;
161 
162 	return 0;
163 }
164 
165 static ssize_t tad_pmu_event_show(struct device *dev,
166 				struct device_attribute *attr, char *page)
167 {
168 	struct perf_pmu_events_attr *pmu_attr;
169 
170 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
171 	return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
172 }
173 
174 #define TAD_PMU_EVENT_ATTR(name, config)			\
175 	PMU_EVENT_ATTR_ID(name, tad_pmu_event_show, config)
176 
177 static struct attribute *tad_pmu_event_attrs[] = {
178 	TAD_PMU_EVENT_ATTR(tad_none, 0x0),
179 	TAD_PMU_EVENT_ATTR(tad_req_msh_in_any, 0x1),
180 	TAD_PMU_EVENT_ATTR(tad_req_msh_in_mn, 0x2),
181 	TAD_PMU_EVENT_ATTR(tad_req_msh_in_exlmn, 0x3),
182 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_in_any, 0x4),
183 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_in_mn, 0x5),
184 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_in_exlmn, 0x6),
185 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_in_dss, 0x7),
186 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_in_retry_dss, 0x8),
187 	TAD_PMU_EVENT_ATTR(tad_dat_msh_in_any, 0x9),
188 	TAD_PMU_EVENT_ATTR(tad_dat_msh_in_dss, 0xa),
189 	TAD_PMU_EVENT_ATTR(tad_req_msh_out_any, 0xb),
190 	TAD_PMU_EVENT_ATTR(tad_req_msh_out_dss_rd, 0xc),
191 	TAD_PMU_EVENT_ATTR(tad_req_msh_out_dss_wr, 0xd),
192 	TAD_PMU_EVENT_ATTR(tad_req_msh_out_evict, 0xe),
193 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_out_any, 0xf),
194 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_out_retry_exlmn, 0x10),
195 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_out_retry_mn, 0x11),
196 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_out_exlmn, 0x12),
197 	TAD_PMU_EVENT_ATTR(tad_rsp_msh_out_mn, 0x13),
198 	TAD_PMU_EVENT_ATTR(tad_snp_msh_out_any, 0x14),
199 	TAD_PMU_EVENT_ATTR(tad_snp_msh_out_mn, 0x15),
200 	TAD_PMU_EVENT_ATTR(tad_snp_msh_out_exlmn, 0x16),
201 	TAD_PMU_EVENT_ATTR(tad_dat_msh_out_any, 0x17),
202 	TAD_PMU_EVENT_ATTR(tad_dat_msh_out_fill, 0x18),
203 	TAD_PMU_EVENT_ATTR(tad_dat_msh_out_dss, 0x19),
204 	TAD_PMU_EVENT_ATTR(tad_alloc_dtg, 0x1a),
205 	TAD_PMU_EVENT_ATTR(tad_alloc_ltg, 0x1b),
206 	TAD_PMU_EVENT_ATTR(tad_alloc_any, 0x1c),
207 	TAD_PMU_EVENT_ATTR(tad_hit_dtg, 0x1d),
208 	TAD_PMU_EVENT_ATTR(tad_hit_ltg, 0x1e),
209 	TAD_PMU_EVENT_ATTR(tad_hit_any, 0x1f),
210 	TAD_PMU_EVENT_ATTR(tad_tag_rd, 0x20),
211 	TAD_PMU_EVENT_ATTR(tad_dat_rd, 0x21),
212 	TAD_PMU_EVENT_ATTR(tad_dat_rd_byp, 0x22),
213 	TAD_PMU_EVENT_ATTR(tad_ifb_occ, 0x23),
214 	TAD_PMU_EVENT_ATTR(tad_req_occ, 0x24),
215 	NULL
216 };
217 
218 static const struct attribute_group tad_pmu_events_attr_group = {
219 	.name = "events",
220 	.attrs = tad_pmu_event_attrs,
221 };
222 
223 PMU_FORMAT_ATTR(event, "config:0-7");
224 
225 static struct attribute *tad_pmu_format_attrs[] = {
226 	&format_attr_event.attr,
227 	NULL
228 };
229 
230 static struct attribute_group tad_pmu_format_attr_group = {
231 	.name = "format",
232 	.attrs = tad_pmu_format_attrs,
233 };
234 
235 static ssize_t tad_pmu_cpumask_show(struct device *dev,
236 				struct device_attribute *attr, char *buf)
237 {
238 	struct tad_pmu *tad_pmu = to_tad_pmu(dev_get_drvdata(dev));
239 
240 	return cpumap_print_to_pagebuf(true, buf, cpumask_of(tad_pmu->cpu));
241 }
242 
243 static DEVICE_ATTR(cpumask, 0444, tad_pmu_cpumask_show, NULL);
244 
245 static struct attribute *tad_pmu_cpumask_attrs[] = {
246 	&dev_attr_cpumask.attr,
247 	NULL
248 };
249 
250 static struct attribute_group tad_pmu_cpumask_attr_group = {
251 	.attrs = tad_pmu_cpumask_attrs,
252 };
253 
254 static const struct attribute_group *tad_pmu_attr_groups[] = {
255 	&tad_pmu_events_attr_group,
256 	&tad_pmu_format_attr_group,
257 	&tad_pmu_cpumask_attr_group,
258 	NULL
259 };
260 
261 static int tad_pmu_probe(struct platform_device *pdev)
262 {
263 	struct device_node *node = pdev->dev.of_node;
264 	struct tad_region *regions;
265 	struct tad_pmu *tad_pmu;
266 	struct resource *res;
267 	u32 tad_pmu_page_size;
268 	u32 tad_page_size;
269 	u32 tad_cnt;
270 	int i, ret;
271 	char *name;
272 
273 	tad_pmu = devm_kzalloc(&pdev->dev, sizeof(*tad_pmu), GFP_KERNEL);
274 	if (!tad_pmu)
275 		return -ENOMEM;
276 
277 	platform_set_drvdata(pdev, tad_pmu);
278 
279 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
280 	if (!res) {
281 		dev_err(&pdev->dev, "Mem resource not found\n");
282 		return -ENODEV;
283 	}
284 
285 	ret = of_property_read_u32(node, "marvell,tad-page-size",
286 				   &tad_page_size);
287 	if (ret) {
288 		dev_err(&pdev->dev, "Can't find tad-page-size property\n");
289 		return ret;
290 	}
291 
292 	ret = of_property_read_u32(node, "marvell,tad-pmu-page-size",
293 				   &tad_pmu_page_size);
294 	if (ret) {
295 		dev_err(&pdev->dev, "Can't find tad-pmu-page-size property\n");
296 		return ret;
297 	}
298 
299 	ret = of_property_read_u32(node, "marvell,tad-cnt", &tad_cnt);
300 	if (ret) {
301 		dev_err(&pdev->dev, "Can't find tad-cnt property\n");
302 		return ret;
303 	}
304 
305 	regions = devm_kcalloc(&pdev->dev, tad_cnt,
306 			       sizeof(*regions), GFP_KERNEL);
307 	if (!regions)
308 		return -ENOMEM;
309 
310 	/* ioremap the distributed TAD pmu regions */
311 	for (i = 0; i < tad_cnt && res->start < res->end; i++) {
312 		regions[i].base = devm_ioremap(&pdev->dev,
313 					       res->start,
314 					       tad_pmu_page_size);
315 		if (!regions[i].base) {
316 			dev_err(&pdev->dev, "TAD%d ioremap fail\n", i);
317 			return -ENOMEM;
318 		}
319 		res->start += tad_page_size;
320 	}
321 
322 	tad_pmu->regions = regions;
323 	tad_pmu->region_cnt = tad_cnt;
324 
325 	tad_pmu->pmu = (struct pmu) {
326 
327 		.module		= THIS_MODULE,
328 		.attr_groups	= tad_pmu_attr_groups,
329 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE |
330 				  PERF_PMU_CAP_NO_INTERRUPT,
331 		.task_ctx_nr	= perf_invalid_context,
332 
333 		.event_init	= tad_pmu_event_init,
334 		.add		= tad_pmu_event_counter_add,
335 		.del		= tad_pmu_event_counter_del,
336 		.start		= tad_pmu_event_counter_start,
337 		.stop		= tad_pmu_event_counter_stop,
338 		.read		= tad_pmu_event_counter_read,
339 	};
340 
341 	tad_pmu->cpu = raw_smp_processor_id();
342 
343 	/* Register pmu instance for cpu hotplug */
344 	ret = cpuhp_state_add_instance_nocalls(tad_pmu_cpuhp_state,
345 					       &tad_pmu->node);
346 	if (ret) {
347 		dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
348 		return ret;
349 	}
350 
351 	name = "tad";
352 	ret = perf_pmu_register(&tad_pmu->pmu, name, -1);
353 	if (ret)
354 		cpuhp_state_remove_instance_nocalls(tad_pmu_cpuhp_state,
355 						    &tad_pmu->node);
356 
357 	return ret;
358 }
359 
360 static int tad_pmu_remove(struct platform_device *pdev)
361 {
362 	struct tad_pmu *pmu = platform_get_drvdata(pdev);
363 
364 	cpuhp_state_remove_instance_nocalls(tad_pmu_cpuhp_state,
365 						&pmu->node);
366 	perf_pmu_unregister(&pmu->pmu);
367 
368 	return 0;
369 }
370 
371 #ifdef CONFIG_OF
372 static const struct of_device_id tad_pmu_of_match[] = {
373 	{ .compatible = "marvell,cn10k-tad-pmu", },
374 	{},
375 };
376 #endif
377 
378 static struct platform_driver tad_pmu_driver = {
379 	.driver         = {
380 		.name   = "cn10k_tad_pmu",
381 		.of_match_table = of_match_ptr(tad_pmu_of_match),
382 		.suppress_bind_attrs = true,
383 	},
384 	.probe          = tad_pmu_probe,
385 	.remove         = tad_pmu_remove,
386 };
387 
388 static int tad_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
389 {
390 	struct tad_pmu *pmu = hlist_entry_safe(node, struct tad_pmu, node);
391 	unsigned int target;
392 
393 	if (cpu != pmu->cpu)
394 		return 0;
395 
396 	target = cpumask_any_but(cpu_online_mask, cpu);
397 	if (target >= nr_cpu_ids)
398 		return 0;
399 
400 	perf_pmu_migrate_context(&pmu->pmu, cpu, target);
401 	pmu->cpu = target;
402 
403 	return 0;
404 }
405 
406 static int __init tad_pmu_init(void)
407 {
408 	int ret;
409 
410 	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
411 				      "perf/cn10k/tadpmu:online",
412 				      NULL,
413 				      tad_pmu_offline_cpu);
414 	if (ret < 0)
415 		return ret;
416 	tad_pmu_cpuhp_state = ret;
417 	return platform_driver_register(&tad_pmu_driver);
418 }
419 
420 static void __exit tad_pmu_exit(void)
421 {
422 	platform_driver_unregister(&tad_pmu_driver);
423 	cpuhp_remove_multi_state(tad_pmu_cpuhp_state);
424 }
425 
426 module_init(tad_pmu_init);
427 module_exit(tad_pmu_exit);
428 
429 MODULE_DESCRIPTION("Marvell CN10K LLC-TAD Perf driver");
430 MODULE_AUTHOR("Bhaskara Budiredla <bbudiredla@marvell.com>");
431 MODULE_LICENSE("GPL v2");
432