xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_perfmon.c (revision 6d99a79c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Broadcom
4  */
5 
6 /**
7  * DOC: VC4 V3D performance monitor module
8  *
9  * The V3D block provides 16 hardware counters which can count various events.
10  */
11 
12 #include "vc4_drv.h"
13 #include "vc4_regs.h"
14 
15 #define VC4_PERFMONID_MIN	1
16 #define VC4_PERFMONID_MAX	U32_MAX
17 
18 void vc4_perfmon_get(struct vc4_perfmon *perfmon)
19 {
20 	if (perfmon)
21 		refcount_inc(&perfmon->refcnt);
22 }
23 
24 void vc4_perfmon_put(struct vc4_perfmon *perfmon)
25 {
26 	if (perfmon && refcount_dec_and_test(&perfmon->refcnt))
27 		kfree(perfmon);
28 }
29 
30 void vc4_perfmon_start(struct vc4_dev *vc4, struct vc4_perfmon *perfmon)
31 {
32 	unsigned int i;
33 	u32 mask;
34 
35 	if (WARN_ON_ONCE(!perfmon || vc4->active_perfmon))
36 		return;
37 
38 	for (i = 0; i < perfmon->ncounters; i++)
39 		V3D_WRITE(V3D_PCTRS(i), perfmon->events[i]);
40 
41 	mask = GENMASK(perfmon->ncounters - 1, 0);
42 	V3D_WRITE(V3D_PCTRC, mask);
43 	V3D_WRITE(V3D_PCTRE, V3D_PCTRE_EN | mask);
44 	vc4->active_perfmon = perfmon;
45 }
46 
47 void vc4_perfmon_stop(struct vc4_dev *vc4, struct vc4_perfmon *perfmon,
48 		      bool capture)
49 {
50 	unsigned int i;
51 
52 	if (WARN_ON_ONCE(!vc4->active_perfmon ||
53 			 perfmon != vc4->active_perfmon))
54 		return;
55 
56 	if (capture) {
57 		for (i = 0; i < perfmon->ncounters; i++)
58 			perfmon->counters[i] += V3D_READ(V3D_PCTR(i));
59 	}
60 
61 	V3D_WRITE(V3D_PCTRE, 0);
62 	vc4->active_perfmon = NULL;
63 }
64 
65 struct vc4_perfmon *vc4_perfmon_find(struct vc4_file *vc4file, int id)
66 {
67 	struct vc4_perfmon *perfmon;
68 
69 	mutex_lock(&vc4file->perfmon.lock);
70 	perfmon = idr_find(&vc4file->perfmon.idr, id);
71 	vc4_perfmon_get(perfmon);
72 	mutex_unlock(&vc4file->perfmon.lock);
73 
74 	return perfmon;
75 }
76 
77 void vc4_perfmon_open_file(struct vc4_file *vc4file)
78 {
79 	mutex_init(&vc4file->perfmon.lock);
80 	idr_init(&vc4file->perfmon.idr);
81 }
82 
83 static int vc4_perfmon_idr_del(int id, void *elem, void *data)
84 {
85 	struct vc4_perfmon *perfmon = elem;
86 
87 	vc4_perfmon_put(perfmon);
88 
89 	return 0;
90 }
91 
92 void vc4_perfmon_close_file(struct vc4_file *vc4file)
93 {
94 	mutex_lock(&vc4file->perfmon.lock);
95 	idr_for_each(&vc4file->perfmon.idr, vc4_perfmon_idr_del, NULL);
96 	idr_destroy(&vc4file->perfmon.idr);
97 	mutex_unlock(&vc4file->perfmon.lock);
98 }
99 
100 int vc4_perfmon_create_ioctl(struct drm_device *dev, void *data,
101 			     struct drm_file *file_priv)
102 {
103 	struct vc4_file *vc4file = file_priv->driver_priv;
104 	struct drm_vc4_perfmon_create *req = data;
105 	struct vc4_perfmon *perfmon;
106 	unsigned int i;
107 	int ret;
108 
109 	/* Number of monitored counters cannot exceed HW limits. */
110 	if (req->ncounters > DRM_VC4_MAX_PERF_COUNTERS ||
111 	    !req->ncounters)
112 		return -EINVAL;
113 
114 	/* Make sure all events are valid. */
115 	for (i = 0; i < req->ncounters; i++) {
116 		if (req->events[i] >= VC4_PERFCNT_NUM_EVENTS)
117 			return -EINVAL;
118 	}
119 
120 	perfmon = kzalloc(sizeof(*perfmon) + (req->ncounters * sizeof(u64)),
121 			  GFP_KERNEL);
122 	if (!perfmon)
123 		return -ENOMEM;
124 
125 	for (i = 0; i < req->ncounters; i++)
126 		perfmon->events[i] = req->events[i];
127 
128 	perfmon->ncounters = req->ncounters;
129 
130 	refcount_set(&perfmon->refcnt, 1);
131 
132 	mutex_lock(&vc4file->perfmon.lock);
133 	ret = idr_alloc(&vc4file->perfmon.idr, perfmon, VC4_PERFMONID_MIN,
134 			VC4_PERFMONID_MAX, GFP_KERNEL);
135 	mutex_unlock(&vc4file->perfmon.lock);
136 
137 	if (ret < 0) {
138 		kfree(perfmon);
139 		return ret;
140 	}
141 
142 	req->id = ret;
143 	return 0;
144 }
145 
146 int vc4_perfmon_destroy_ioctl(struct drm_device *dev, void *data,
147 			      struct drm_file *file_priv)
148 {
149 	struct vc4_file *vc4file = file_priv->driver_priv;
150 	struct drm_vc4_perfmon_destroy *req = data;
151 	struct vc4_perfmon *perfmon;
152 
153 	mutex_lock(&vc4file->perfmon.lock);
154 	perfmon = idr_remove(&vc4file->perfmon.idr, req->id);
155 	mutex_unlock(&vc4file->perfmon.lock);
156 
157 	if (!perfmon)
158 		return -EINVAL;
159 
160 	vc4_perfmon_put(perfmon);
161 	return 0;
162 }
163 
164 int vc4_perfmon_get_values_ioctl(struct drm_device *dev, void *data,
165 				 struct drm_file *file_priv)
166 {
167 	struct vc4_file *vc4file = file_priv->driver_priv;
168 	struct drm_vc4_perfmon_get_values *req = data;
169 	struct vc4_perfmon *perfmon;
170 	int ret;
171 
172 	mutex_lock(&vc4file->perfmon.lock);
173 	perfmon = idr_find(&vc4file->perfmon.idr, req->id);
174 	vc4_perfmon_get(perfmon);
175 	mutex_unlock(&vc4file->perfmon.lock);
176 
177 	if (!perfmon)
178 		return -EINVAL;
179 
180 	if (copy_to_user(u64_to_user_ptr(req->values_ptr), perfmon->counters,
181 			 perfmon->ncounters * sizeof(u64)))
182 		ret = -EFAULT;
183 	else
184 		ret = 0;
185 
186 	vc4_perfmon_put(perfmon);
187 	return ret;
188 }
189