1 /*
2  * Copyright 2019 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Author: Jonathan Kim <jonathan.kim@amd.com>
23  *
24  */
25 
26 #include <linux/perf_event.h>
27 #include <linux/init.h>
28 #include "amdgpu.h"
29 #include "amdgpu_pmu.h"
30 #include "df_v3_6.h"
31 
32 #define PMU_NAME_SIZE 32
33 
34 /* record to keep track of pmu entry per pmu type per device */
35 struct amdgpu_pmu_entry {
36 	struct list_head entry;
37 	struct amdgpu_device *adev;
38 	struct pmu pmu;
39 	unsigned int pmu_perf_type;
40 };
41 
42 static LIST_HEAD(amdgpu_pmu_list);
43 
44 
45 /* initialize perf counter */
46 static int amdgpu_perf_event_init(struct perf_event *event)
47 {
48 	struct hw_perf_event *hwc = &event->hw;
49 
50 	/* test the event attr type check for PMU enumeration */
51 	if (event->attr.type != event->pmu->type)
52 		return -ENOENT;
53 
54 	/* update the hw_perf_event struct with config data */
55 	hwc->config = event->attr.config;
56 
57 	return 0;
58 }
59 
60 /* start perf counter */
61 static void amdgpu_perf_start(struct perf_event *event, int flags)
62 {
63 	struct hw_perf_event *hwc = &event->hw;
64 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
65 						  struct amdgpu_pmu_entry,
66 						  pmu);
67 
68 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
69 		return;
70 
71 	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
72 	hwc->state = 0;
73 
74 	switch (pe->pmu_perf_type) {
75 	case PERF_TYPE_AMDGPU_DF:
76 		if (!(flags & PERF_EF_RELOAD))
77 			pe->adev->df.funcs->pmc_start(pe->adev, hwc->config, 1);
78 
79 		pe->adev->df.funcs->pmc_start(pe->adev, hwc->config, 0);
80 		break;
81 	default:
82 		break;
83 	}
84 
85 	perf_event_update_userpage(event);
86 
87 }
88 
89 /* read perf counter */
90 static void amdgpu_perf_read(struct perf_event *event)
91 {
92 	struct hw_perf_event *hwc = &event->hw;
93 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
94 						  struct amdgpu_pmu_entry,
95 						  pmu);
96 
97 	u64 count, prev;
98 
99 	do {
100 		prev = local64_read(&hwc->prev_count);
101 
102 		switch (pe->pmu_perf_type) {
103 		case PERF_TYPE_AMDGPU_DF:
104 			pe->adev->df.funcs->pmc_get_count(pe->adev, hwc->config,
105 							  &count);
106 			break;
107 		default:
108 			count = 0;
109 			break;
110 		}
111 	} while (local64_cmpxchg(&hwc->prev_count, prev, count) != prev);
112 
113 	local64_add(count - prev, &event->count);
114 }
115 
116 /* stop perf counter */
117 static void amdgpu_perf_stop(struct perf_event *event, int flags)
118 {
119 	struct hw_perf_event *hwc = &event->hw;
120 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
121 						  struct amdgpu_pmu_entry,
122 						  pmu);
123 
124 	if (hwc->state & PERF_HES_UPTODATE)
125 		return;
126 
127 	switch (pe->pmu_perf_type) {
128 	case PERF_TYPE_AMDGPU_DF:
129 		pe->adev->df.funcs->pmc_stop(pe->adev, hwc->config, 0);
130 		break;
131 	default:
132 		break;
133 	}
134 
135 	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
136 	hwc->state |= PERF_HES_STOPPED;
137 
138 	if (hwc->state & PERF_HES_UPTODATE)
139 		return;
140 
141 	amdgpu_perf_read(event);
142 	hwc->state |= PERF_HES_UPTODATE;
143 }
144 
145 /* add perf counter  */
146 static int amdgpu_perf_add(struct perf_event *event, int flags)
147 {
148 	struct hw_perf_event *hwc = &event->hw;
149 	int retval;
150 
151 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
152 						  struct amdgpu_pmu_entry,
153 						  pmu);
154 
155 	event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
156 
157 	switch (pe->pmu_perf_type) {
158 	case PERF_TYPE_AMDGPU_DF:
159 		retval = pe->adev->df.funcs->pmc_start(pe->adev,
160 						       hwc->config, 1);
161 		break;
162 	default:
163 		return 0;
164 	}
165 
166 	if (retval)
167 		return retval;
168 
169 	if (flags & PERF_EF_START)
170 		amdgpu_perf_start(event, PERF_EF_RELOAD);
171 
172 	return retval;
173 
174 }
175 
176 /* delete perf counter  */
177 static void amdgpu_perf_del(struct perf_event *event, int flags)
178 {
179 	struct hw_perf_event *hwc = &event->hw;
180 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
181 						  struct amdgpu_pmu_entry,
182 						  pmu);
183 
184 	amdgpu_perf_stop(event, PERF_EF_UPDATE);
185 
186 	switch (pe->pmu_perf_type) {
187 	case PERF_TYPE_AMDGPU_DF:
188 		pe->adev->df.funcs->pmc_stop(pe->adev, hwc->config, 1);
189 		break;
190 	default:
191 		break;
192 	}
193 
194 	perf_event_update_userpage(event);
195 }
196 
197 /* vega20 pmus */
198 
199 /* init pmu tracking per pmu type */
200 static int init_pmu_by_type(struct amdgpu_device *adev,
201 		  const struct attribute_group *attr_groups[],
202 		  char *pmu_type_name, char *pmu_file_prefix,
203 		  unsigned int pmu_perf_type,
204 		  unsigned int num_counters)
205 {
206 	char pmu_name[PMU_NAME_SIZE];
207 	struct amdgpu_pmu_entry *pmu_entry;
208 	int ret = 0;
209 
210 	pmu_entry = kzalloc(sizeof(struct amdgpu_pmu_entry), GFP_KERNEL);
211 
212 	if (!pmu_entry)
213 		return -ENOMEM;
214 
215 	pmu_entry->adev = adev;
216 	pmu_entry->pmu = (struct pmu){
217 		.event_init = amdgpu_perf_event_init,
218 		.add = amdgpu_perf_add,
219 		.del = amdgpu_perf_del,
220 		.start = amdgpu_perf_start,
221 		.stop = amdgpu_perf_stop,
222 		.read = amdgpu_perf_read,
223 		.task_ctx_nr = perf_invalid_context,
224 	};
225 
226 	pmu_entry->pmu.attr_groups = attr_groups;
227 	pmu_entry->pmu_perf_type = pmu_perf_type;
228 	snprintf(pmu_name, PMU_NAME_SIZE, "%s_%d",
229 				pmu_file_prefix, adev_to_drm(adev)->primary->index);
230 
231 	ret = perf_pmu_register(&pmu_entry->pmu, pmu_name, -1);
232 
233 	if (ret) {
234 		kfree(pmu_entry);
235 		pr_warn("Error initializing AMDGPU %s PMUs.\n", pmu_type_name);
236 		return ret;
237 	}
238 
239 	pr_info("Detected AMDGPU %s Counters. # of Counters = %d.\n",
240 			pmu_type_name, num_counters);
241 
242 	list_add_tail(&pmu_entry->entry, &amdgpu_pmu_list);
243 
244 	return 0;
245 }
246 
247 /* init amdgpu_pmu */
248 int amdgpu_pmu_init(struct amdgpu_device *adev)
249 {
250 	int ret = 0;
251 
252 	switch (adev->asic_type) {
253 	case CHIP_VEGA20:
254 		/* init df */
255 		ret = init_pmu_by_type(adev, df_v3_6_attr_groups,
256 				       "DF", "amdgpu_df", PERF_TYPE_AMDGPU_DF,
257 				       DF_V3_6_MAX_COUNTERS);
258 
259 		/* other pmu types go here*/
260 		break;
261 	default:
262 		return 0;
263 	}
264 
265 	return 0;
266 }
267 
268 
269 /* destroy all pmu data associated with target device */
270 void amdgpu_pmu_fini(struct amdgpu_device *adev)
271 {
272 	struct amdgpu_pmu_entry *pe, *temp;
273 
274 	list_for_each_entry_safe(pe, temp, &amdgpu_pmu_list, entry) {
275 		if (pe->adev == adev) {
276 			list_del(&pe->entry);
277 			perf_pmu_unregister(&pe->pmu);
278 			kfree(pe);
279 		}
280 	}
281 }
282