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->conf = 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->conf, 1);
78 
79 		pe->adev->df_funcs->pmc_start(pe->adev, hwc->conf, 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->conf,
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->conf, 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, hwc->conf, 1);
160 		break;
161 	default:
162 		return 0;
163 	};
164 
165 	if (retval)
166 		return retval;
167 
168 	if (flags & PERF_EF_START)
169 		amdgpu_perf_start(event, PERF_EF_RELOAD);
170 
171 	return retval;
172 
173 }
174 
175 /* delete perf counter  */
176 static void amdgpu_perf_del(struct perf_event *event, int flags)
177 {
178 	struct hw_perf_event *hwc = &event->hw;
179 	struct amdgpu_pmu_entry *pe = container_of(event->pmu,
180 						  struct amdgpu_pmu_entry,
181 						  pmu);
182 
183 	amdgpu_perf_stop(event, PERF_EF_UPDATE);
184 
185 	switch (pe->pmu_perf_type) {
186 	case PERF_TYPE_AMDGPU_DF:
187 		pe->adev->df_funcs->pmc_stop(pe->adev, hwc->conf, 1);
188 		break;
189 	default:
190 		break;
191 	};
192 
193 	perf_event_update_userpage(event);
194 }
195 
196 /* vega20 pmus */
197 
198 /* init pmu tracking per pmu type */
199 static int init_pmu_by_type(struct amdgpu_device *adev,
200 		  const struct attribute_group *attr_groups[],
201 		  char *pmu_type_name, char *pmu_file_prefix,
202 		  unsigned int pmu_perf_type,
203 		  unsigned int num_counters)
204 {
205 	char pmu_name[PMU_NAME_SIZE];
206 	struct amdgpu_pmu_entry *pmu_entry;
207 	int ret = 0;
208 
209 	pmu_entry = kzalloc(sizeof(struct amdgpu_pmu_entry), GFP_KERNEL);
210 
211 	if (!pmu_entry)
212 		return -ENOMEM;
213 
214 	pmu_entry->adev = adev;
215 	pmu_entry->pmu = (struct pmu){
216 		.event_init = amdgpu_perf_event_init,
217 		.add = amdgpu_perf_add,
218 		.del = amdgpu_perf_del,
219 		.start = amdgpu_perf_start,
220 		.stop = amdgpu_perf_stop,
221 		.read = amdgpu_perf_read,
222 		.task_ctx_nr = perf_invalid_context,
223 	};
224 
225 	pmu_entry->pmu.attr_groups = attr_groups;
226 	pmu_entry->pmu_perf_type = pmu_perf_type;
227 	snprintf(pmu_name, PMU_NAME_SIZE, "%s_%d",
228 				pmu_file_prefix, adev->ddev->primary->index);
229 
230 	ret = perf_pmu_register(&pmu_entry->pmu, pmu_name, -1);
231 
232 	if (ret) {
233 		kfree(pmu_entry);
234 		pr_warn("Error initializing AMDGPU %s PMUs.\n", pmu_type_name);
235 		return ret;
236 	}
237 
238 	pr_info("Detected AMDGPU %s Counters. # of Counters = %d.\n",
239 			pmu_type_name, num_counters);
240 
241 	list_add_tail(&pmu_entry->entry, &amdgpu_pmu_list);
242 
243 	return 0;
244 }
245 
246 /* init amdgpu_pmu */
247 int amdgpu_pmu_init(struct amdgpu_device *adev)
248 {
249 	int ret = 0;
250 
251 	switch (adev->asic_type) {
252 	case CHIP_VEGA20:
253 		/* init df */
254 		ret = init_pmu_by_type(adev, df_v3_6_attr_groups,
255 				       "DF", "amdgpu_df", PERF_TYPE_AMDGPU_DF,
256 				       DF_V3_6_MAX_COUNTERS);
257 
258 		/* other pmu types go here*/
259 		break;
260 	default:
261 		return 0;
262 	}
263 
264 	return 0;
265 }
266 
267 
268 /* destroy all pmu data associated with target device */
269 void amdgpu_pmu_fini(struct amdgpu_device *adev)
270 {
271 	struct amdgpu_pmu_entry *pe, *temp;
272 
273 	list_for_each_entry_safe(pe, temp, &amdgpu_pmu_list, entry) {
274 		if (pe->adev == adev) {
275 			list_del(&pe->entry);
276 			perf_pmu_unregister(&pe->pmu);
277 			kfree(pe);
278 		}
279 	}
280 }
281